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I am going to be heading to Geneva (CERN) Nov. 10, getting in on Nov. 11, for a three day conference on the coming upgrades to the ATLAS detector at the Large Hadron Collider (I worked on the New Small Wheel due to be installed in the next couple of years, but I am mostly working on the replacement for the inner tracker [ITk] due to be installed in 2025 or so). From there, I will be flying to London, and then taking the train to Oxford where I will be staying until Dec. 4 (commuting to/from the Rutherford Appleton Laboratory on the weekdays). If you're in the area (where area is quite a broad notion with tremendous flexibility... I will at least be popping into London from time to time), and care to get together for some tea or a pint, let me know.

Also, I have posted the latest instalment (i.e. the second one) of something I'm experimenting with called Phelonius' Pedantic Solutions where I solve a physics problem in painful exacting detail, where I moot the mathematical and conceptual tools needed as I go. In essence, this is the kind of stuff I wish I had when I was doing my undergraduate degree. The latest just builds and solves the differential equation for exponential growth/decay that is used in just about every field of science and engineering.

Decay and growth rates

My first entry was Relativistic energy expansion, which uses Taylor expansion on the relativistic version of E=mc2 to reproduce a comment in Griffith's particle physics textbook.

I would have preferred to have posted them on Dreamwidth, but I needed MathJax and the last couple of times I've checked, it just wasn't supported. YouTube seems to be broken as I post this, so no video today...
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I will be Geneva (CERN) from Nov. 11 through Nov. 15, and then Oxford (with side trips to London) from Nov. 15 through Dec. 4 (flying out of London Dec. 5). DM me if you want to get together for tea or a pint :).

I will be in Geneva for the ATLAS experiment's fall Upgrade Week and then will be travelling to the UK to work mostly at the Rutherford Appleton Laboratory to help test the new front-end readout ASIC (Application-Specific Integrated Circuit) for the ITk inner tracker upgrade project (this version of the chip is supposed to be the one that is actually used in the detector, set for installation in 2025 or so — the chips I've been working with so far have been the earlier prototypes).

Listening to Ume as I continue to code, and code, and code... hardcore, but fresh and exciting, imo. Amazing how the lead singer/lead guitar player goes between harsh and soft. Listen to the whole Antiquiet session if you get a chance!

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I am heading to Geneva today (arriving Friday morning local time) for a 10 day stay at CERN to participate in a workshop on the sTGC (small-wire Thin Gap Chamber) detector DAQ (Data AcQuisition) system. The sTGC is part of the NSW upgrade (New Small Wheel... where "small" is extremely relative as the "wheel" is 10 metres across) to the ATLAS (worst acronym ever, makes me cringe every time, A Toroidal LHC ApparatuS, ugh) experiment at the LHC due to be installed in 2019. Once past the alphabet soup, I am very excited to be going as this is my first time there!

If you are at all curious about the New Small Wheel project (and/or the sTGC in specific), here is a good summary article on the subject. If you look at the group picture of the testbeam team at Fermilab, I'm the bald guy at the back in the CKCU t-shirt...

https://www.sciencedirect.com/science/article/pii/S2405601415006719

Important note: the article is not behind a paywall :). You can download the PDF.

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I just got back from a talk on the DEAP-3600 experiment by DEAP Project Director, Dr. Mark Boulay. While I didn't learn much in the way of physics per se, it certainly gave me an appreciation of the scientific and engineering feat of building such an instrument 2km underground (spoiler: everything is radioactive in some way, but DEAP-3600 is one of the least radioactively contaminated instruments ever built, and certainly in a class of its own considering its size: the "3600" is for the number of kilograms of liquid argon that makes up the detector volume).

So, the background is that we have discovered that everything we have ever measured in human history (which is described by a stunningly successful framework called The Standard Model of particle physics) is about 5% of what the universe is made of. About 27% is made of something we call dark matter, and the remaining 69% or so is made of something we call dark energy. We know almost nothing about dark matter except that we have seen its gravitational effects when we look out into the universe (it's very convincing once you see all the evidence), but we have no idea what it might be and there have been no direct observations of such a thing and we're not even sure what to look for. We know absolutely nothing about dark energy except that it is making the universe expand faster and faster (again, the evidence is strong, but our clues are zero). So, we really don't have a lot of clues about what makes up 95% of our universe!

The DEAP-3600 experiment is looking for a dark matter candidate called a WIMP. Yup. A WIMP, which stands for Weakly Interacting Massive Particle. We know dark matter exists, but we've never observed anything but its gravitational effects. Based on experiments, we are pretty darned sure that dark matter doesn't interact electromagnetically (it is dark after all), or seemingly with the strong force (which holds atomic nuclei and certain subatomic particles like protons and neutrons together). That leaves two forces: gravity (which we know it interacts with), and the weak force (which is responsible for radioactive decay and other stuff). I asked this evening and confirmed that the "Weakly Interacting" in WIMP doesn't mean that it doesn't interact much (well, it doesn't, but...) but means that they are hoping that it interacts with regular matter (that 5% we know anything about) through the weak force. I also confirmed that if dark matter doesn't interact through the weak force, that DEAP-3600 and all the other detectors being built around the world to look for dark matter would not be able to detect it.

When I think of something tiny but "massive"... that it has weight in a gravitational field (inertia wherever it is)... running into an atomic nucleus or something, I envision a little marble hitting a billiard ball. In such a case, the billard ball will absord some energy from the marble (and if there's no friction, it would start to move in the opposite direction from the marble that hit it... remember, "equal and opposite reaction"). But a marble hitting a billiard ball is actually an electromagnetic interaction (when you try to push your hands together, it is light being emitted by the electrons in your atoms keeping your hands from passing through each other and forcing them apart when they get close... what we feel as "solid"). In these dark matter detectors, that are relying on the weak force, the recoil of the nuclei would be due to the exchange of the weak force particles (the Z and W bosons) and you still get an energy transfer kind of like the way the electromagnetic force works (in fact, the two forces have been combined mathematically into a single "electroweak" theory, but that's another story). But... if they don't interact weakly, they would only interact gravitationally and would likely pass right through the nuclei of atoms as if they weren't there (as if matter was empty space). So that was my revelation this evening: trying to imagine how particles (if that's what we want to call them) that only interact gravitationally would behave as they passed through matter. And if so, could we ever detect such particles (see the video above on The Standard Model to see how weak gravity is compared to the other forces)? Another thought that occurred to me (in my ignorance) is to consider the hypothesized "graviton", which is supposed to be a very, very small particle (again, if it exists at all), but instead ask a different question: if the Higgs particle is a resonance in the Higgs field that permeates the universe, could dark matter be a similar resonance in the gravitational field? But where we think of gravitons as tiny, maybe these resonances are huge (maybe there are different order resonances, but the higher order resonances of other quantum fields would be too massive to make any difference in our universe, but since gravity is so weak, higher order resonances could possibly exist and have an effect). Until I take quantum field theory, there is no way to know if what I'm saying is hogwash or not (I'm flying purely intuitively, which is a strength of mine, but quantum theory does not always lend itself to interpretation through intuition). I guess that would also make them GIMPs...

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Sadly, at this point, it's all a blur. The week itself turned out to be mostly an intense learning curve amidst a fine bout of jet lag, punctuated by an occasional meal out with a pint here and there (okay, maybe more pints than that). On the Sunday after I arrived (I got there on a Saturday), I found out that there weren't really any breakfast places in the neighbourhood that opened in time for me to go to them on my way to work, so I went to that little shop near me (which was actually surprisingly useful and of fairly good quality... it's on Woodstock Road in a little mall with a dry cleaners place, etc.) and purchased some eggs, milk, vegetables, cheese, ham, pesto, and some apple juice so I could eat before leaving. I had forgotten to buy butter, so the first omelet I had was fried in cheese and pesto. It was good, but probably not so good for me. I bought tea, butter, and bread Monday evening ;). The guy I was working with has to take his child to school so did not get in until 9:30AM or so (quite civilized as far as start times go, imho) and that meant that I needed to be on the 8:40AM Science Transit Shuttle to RAL from Oxford. I pretty much needed to be up at 6:30AM Oxford time to shower, eat, and get to the stop on time. The project was successful! He met me when I got there, so it worked out pretty well and he got me a temporary visitor's pass to enter. I got a proper pass a little later in the week, so I could then let myself in and out of the facility. That also means I can add the Diamond Light Source as another particle accelerator facility I have been to (so far, the list is TRIUMF, Fermilab, and DESY). I didn't have time to try to get a tour (much less go on one), but I do hope to be back in the future and will plan ahead if that happens.

As reported in an earlier post, the food there was pretty hit or miss, with more misses than I would have liked. As such, I started buying ingredients to just cook in my flat and made a lovely vegetable-heavy chicken marinara-inspired sauce that I had with penne and a piece of that bread (which was just Tesco in-store bakery bread, but it was very dense but still quite soft... quite yummy) with butter and some wine (which is sold everywhere along with bottled beer). I did try and check a bunch of things off my "food to do" list while there, so Monday I went to a thali restaurant at the end of George Street and had an enjoyable meal with curry and lots of other yummy, tasty foods (that was a hit). As an aside, it irks me that not more Indian places have thali plates... it is just kind of wrong for one person to go in and order a full plate of one thing (like palak paneer), much less more than one thing, plus rice. Even with a couple of people, having a mixed plate makes for a nicer meal I find, since doing a set of full plates and sharing is best for four people and up. Just my opinion anyway. My other success that week was going into a pub called The White Horse in Oxford on Broad Street (just next to the famous Blackwell's Books, more on that in a later post). It definitely felt the most "British Pub" to me of all the places I'd been to that point, and I understand it was often featured in the show Inspector Morse as a setting for a pint (for example, in the episode "The Dead of Jericho"... I've set the clip to start in the pub, it's only a few seconds, fyi). I got another "food check mark" as well as I ordered Toad In The Hole there (along with a couple of pints). The dish was basically a giant Yorkshire pudding bowl filled with potatoes, peas, sausage, and broccoli with a pot of their onion gravy on the side. I had never had such a Yorkshire pudding presentation before and it was just the right amount of crispy and was fluffy in the right places, absolutely a delightful meal! The ales I had were also delicious and were made locally and poured using hand-driven pumps set into the bar (another first for me). The temperature was absolutely perfect (below room temperatute, but definitely not cold) and the bubbles were small and refreshing and made the brew a tasty and easy to drink experience. I'm now a big fan of properly brewed and served ales, and will have to wait to cross the pond again because I've never had it anywhere else in the world I've been to (and I hear that pubs are endangered in the UK... several were pointed out to me in the UCL area in London as either being torn down to redevelop the area or were bought out by yuppies and turned into wine bars or something... definitely a tragedy because it is unique to there it seems). Note: the fucking terrible meal I had at Browns Brasserie & Bar was on Tuesday I think... definitely before the meal at The White Horse (which I think was Thursday), so the latter event definitely redeemed the possibility of UK restaurants to me. As a final aside on this part of the tale, there is also a White Horse Brewery in Oxfordshire which, gasp, has beers available in The White Horse pub. The brewery's slogan is "We brew beer to drink & what we have left we sell". Lol! They definitely do more traditional tasting beers, which I really appreciated, as so many small breweries are doing IPAs that are overwhelming in their flavours (North American style as one co-worker put it). These were flavourful, but balanced (although they do make IPAs as well... not ones to balk at a market for their products, heh).

As for productivity, I was able to see every phase of the testing that needed to get done: from changing the wafers, to aligning and setting the height on the probe station, to running the tests and adapting as things went, to making enhancements to the software driving the probe station and running the tests. I finally got a chance (once things were running semi-automated) to do the first real deep dive into the data acquisition code for the system and learned its architecture. Fyi, my job there was to decipher what is needed to test the integrated circuits on the wafers at the lowest level so that I could take just the part that tests the chips and duplicate it on the systems at the company we are partnering with here in Ottawa. Basically the company is a traditional integrated circuit test house whereas the folks at RAL are physicists that have put together their own system and process... the two are inherently incompatible. Again, I need to learn what is being done in the physics labs and turn that into a process that can be run on industry standard equipment (and again, that involves understanding the test software and hardware down to the level of when and how to set each bit, what commands to send, and what measurements to take). By the end of the week, I had a pretty good idea of how to do it and was at least able to start asking precise, and useful questions that could then be answered by the experts on the system. If you want to read up on the ATLAS experiment ITk (inner tracker) upgrade project, there is a good introductory presentation here (PDF). I am learning how to test the ABC130 front-end integrated circuits while they are still on the wafer, before it is diced into individual chips for assembly. Note that because of the unique constraints of building an inner detector, as little material as possible must be used to minimize the chances that particles from collisions will interact with the non-sensor parts of the system. As such, the chips are never packaged: they are glued and wire-bonded onto a thin kapton printed circuit board, which is then glued to a huge silicon sensor where the chips are then bonded directly to the individual channels of the detector. This is a very strange configuration and it's weirding out anyone in the electronics industry we talk to about it ;). One negative comment I have to make about the Rutherford Appleton Laboratory is its cafeteria is absolutely atrocious... I will never forget the half fat and grissle pork chop plopped on a plate of grey beans in a flavourless grey "sauce" as long as I live (seriously, we're talking concrete grey here)... and that was the best option they had that day at the 8 or 9 stations they run... although it was still better than that meal I had at Browns (remember, it was in the top 3 worst meals I've ever had... doubly so because of the price).

Finally for this installment, that week I finally managed to finish the book "Antarctica" by Kim Stanley Robinson (of Mars Trilogy fame). Good lard, that man needs to get over himself. It was probably the most pompous and long-winded book of "fiction" I have ever had to slog through... this is a guy who loves to hear his own voice and wanted to make sure that you were exposed to every little bit of data he had and research he had done on the subject of Antarctica. If you poked him with a needle, he would fweeeeeeeee around the room like that gas bag beach ball alien in Dark Star (as an aside, the fact that they managed to give a beach ball that much personality is an amazing cinematic feat, see below). Go ahead, ask me how I felt about reading it over the months it took me... ugh. Here is an actual sentence, one sentence, from page 2 (page 2!)... and I'm not making this up, it is verbatim: "And so there you are riding in the enclosed cab of a giant transport vehicle, still thinking about that girlfriend, ten thousand feet above sea level, in the dark of the long night; and as you sit there looking out the cab windows, the sky gradually lightens to the day's one hour of twilight, shifting in invisible stages from a star-cluttered black pool to a dome of glowing indigo lying close overhead; and in that pure transparent indigo floats the thinnest new moon imaginable, a mere sliver of a crescent, which nevertheless illuminates very clearly the great ocean of ice rolling to the horizon in all directions, the moonlight glittering on the snow, gleaming on the ice, and all of it tinted the same vivid indigo as the sky; everything still and motionless; the clarity of the light unlike anything you've ever seen, like nothing on Earth, and you are all alone in it, the only witness, the sole inhabitant of the planet it seems; and the uncanny beauty of the scene rises in you and clamps your chest tight, and your heart breaks then simply because it is squeezed so hard, because the world is so spacious and pure and beautiful, and because moments like this one are so transient —impossible to imagine beforehand, impossible to remember afterward, and never to be returned to, never ever." There are 651 pages of that and I'm glad there is nothing high for me to jump off right now. As with his other books, it is technically brilliant and researched in a manner that only Robinson can and does (he, in fact, spent a season in Antarctica in 1995 as part of the National Science Foundation's "U.S. Antarctic Program's Artists and Writers' Program and you really do get to see the sense of wonder he felt at being in such an alien place on our own planet). Where it falls down heavily (writing style aside) is that the characters are completely forgettable, if not unbearably annoying (and not because that's part of their character, they're just badly written). If this had been presented as the diary of a "personal journey" (a work of non-fiction), I am sure I would have enjoyed it much more, but trying to hammer every bit of knowledge and feeling he had into a thinly hung together plot with hollow characters did his experience there a great disservice... it was also one of the "whitest" books I've read in a while (and that is not a snow reference). I don't know if he needed a better editor or what, but this book is definitely never going to cycle into my "hmmm, I should read that again" pile (his Mars trilogy does fall into that category, so... it was because them that I persevered on this one). After that, I turned to Becky Chambers' book "the long way to a small angry planet" which proved a wonderful palate cleanser and was as much of a page-turner as Antarctica was a page-dragger (I'm still glad I read it because it's interesting seeing other people's visions of such a strange place, but ... 'nuf said). More on that later as I think I need to wrap this up now. Thanksgiving dinner is nearing completion and I should get back to it... yes, I picked up my car yesterday evening after my flight (it was parked at Carleton while I was gone because they were paving where I live... it's done now), went to the grocery store and wine shop on my way home, and am making a big dinner today (well, okay, Beep and Happy are doing the vegetable stuff and I'm doing the meats... a cured pork shoulder steamed in apple cider to be served with pineapple, a Quebecois meat tourtiere, and a pre-cooked chicken since they were out of turkeys at the grocery store I went to).

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I also just found out today (after the previous good news email already reported on) that I will be issued with a work visa for the UK "by way of ancestry" (my grandfather was British and moved to Canada after the war, and Canada is still a Commonwealth country). It's a 5 year multi-entry visa with quite liberal requirements for working in the UK (as long as I can support myself for a reasonable period of time, I can even go to look for work rather than having to have a job in hand at the border). My employer, Carleton University here in Canada, is going to pay for my travel, lodgings, and other expenses while I'm there (along with my salary, of course), so I will just be shifting money to the local economies in the area in return for hands-on experience. It is going to be used over the next few years (presumably) to spend a few weeks at a time at the Rutherford Appleton Laboratory (RAL) near Oxford (in Oxfordshire) to work on the Phase II upgrades to the ATLAS detector at the Large Hadron Collider (LHC) at CERN due to be installed in 2025 (at which point it will become the HL-LHC or High Luminosity LHC). Heady times! I'll be staying in a flat for visiting scientists at St. John's College at Oxford and I'm already crazy excited at just the prospect of that (I'm easily contented apparently)! It also looks like I will have a couple of days in Oxford or London to do a bit of touristy type stuff... now I just have to figure out what to do with that time... hmmmm. I'll be spending my birthday there (on a Saturday yet), which will be a marvy way of marking my having survived another year and a fine excuse to treat myself with something fun.

Without the work visa, I could not have so much as picked up a paper clip to contribute to the project (RAL is a government institution and is very strict about such things), and I would only have been able to go and observe which would have defeated the main purpose of my going there (to learn how to do this stuff so we can help going forward since it's too much work to do in one place). I was, to be honest, stressed out of my mind about the whole thing because the non-refundable airline tickets are already purchased and the UK embassy in New York has my passport as part of the application process (which could have presented a travel issue if it was not returned in time, which could have happened if the application took longer than it normally does, which is a possibility in these sorts of things). So my stress level has dropped by orders of magnitude to say the least! So, I leave for Gatwick from Ottawa on September 22 and will be returning here on October 8.

If you're in the London/Oxford area then, I'd be happy to go for a pint (or a cup of tea of that's more your speed) while I'm there :-).
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I have so much I want to do, so much pent-up desire (and sometimes need) to accomplish so many things after eight years as a "mature" (or at least elderly) undergraduate student. So many business ideas, so many technical ideas, so many geekly fun for myself ideas, so many social ideas, but I remain mired in making it from one day to the next. I really should have taken some time off to get my head straight, but it just didn't work out that way (in fact, I had negative amounts of time off because I started working for the university part time months before my semester was over, and was full time before my finals were written). With all that said, the reason was the bane of my hopes to accomplish the things I want: opportunity. The chances to work on things too cool for school (if you'll pardon the phrase as I am still, for all intents and purposes, at school) was too much to resist. It comes at a cost though for sure.

So where are things now, well, as stated, I am working on some truly amazing projects right now. These include both the Phase 1 (New Small Wheel muon tracker/trigger [not actually very small, fyi], in particular the small-wire Thin Gap Chamber, sTGC, sub-project that I did the testbeam at Fermilab for a few years back as a student research assistant and got authorship on a peer-reviewed journal article by working on) and Phase 2 (silicon inner tracker, ITk, in particular the end-cap strips sensors sub-project) upgrades for the ATLAS experiment at the Large Hadron Collider at CERN (which will be upgraded to the High-Luminosity Large Hadron Detector with the replacement of the inner tracker system in 2025).

If all goes well, I just applied for a 5 year work visa for the UK (by way of UK Ancestry... my grandfather was born in Measham), and if I get it I will go for two weeks in mid-September (I've never been to the UK) to help test 48 wafers of a new batch of ASICs (integrated circuit chips, 450 per wafer) for the ITk project as part of a plan to start testing wafers here in Ottawa. There are hundreds of thousands of ASIC chips and thousands of sensors to be tested for the final detector, and we need multiple sites to do it at... Canada built the forward calorimeter for the current incarnation of ATLAS, and is working on the gas-filled detectors, the sTGCs, but this is the first time we've done silicon trackers like these, or at least on this scale. Anyway, if the visa thing works out, I might be going to RAL in the UK periodically over the next few years to work on this particular aspect of the project. I was supposed to make a side trip to CERN for the "ITk Week" where physicists from all over the world working on that project get together (I've never been there either, but I have been to TRIUMF, Fermilab, and DESY), but we're not sure when the wafers are going to be in, so it's kind of up in the air right now whether or not I make it to Switzerland (which I've never been to either).

I am also working on the Cryogenic Underground TEst facility (sorry, a PDF is all I could find that was public... slide 2 is worth checking it out for), CUTE (yes, CUTE...), which is an experiment that is part of the search for dark matter that will be installed at SNOLAB, 2km underground, early next year. It is going to use a 1kg chunk of ultra-pure germanium as its main detector element (huge for something like that, and crazy expensive). I have heard rumours that I may be asked to spend 6 weeks underground (well, heading underground each day... 5AM, ugh, but this will be for science!)... the first two weeks training (it's an active nickel mine in Sudbury, so there are real mining dangers on top of the danger of just being that far underground), and the next four weeks actually doing work. I had a chance to visit SNOLAB a couple of years back (I never got around to properly posting about it, which I am sad about), but I did post a couple of pictures I took while there. It really is like a villain lair from a Bond film or something... it's pretty surreal.

The other cluster of reasons why I am still not even close to being recovered from my undergraduate degrees is moving... and not even me. Firstly, my partner (we've been dating for a few years) could not find full time employment (much less anything with benefits) here in Ottawa (due to the way the federal government outsourced language training to a cartel), so had to move to Shanghai, China (teaching English as a Foreign Language) to get a living wage and extended medical insurance (we have universal health care, but it doesn't cover everything... like prescriptions and glasses and dental work unless they are outrageously expensive treatments or emergencies, for instance... I wouldn't trade it for the world having lived the alternative for a suffiently long time, but that's another story). She moved mid-June and that effort just about killed me dead (international moves are big things, I've done them before, but she didn't have a lot of resources, so sweat replaced money for a lot of things that had to get done). I did a radio inteview with her the week before she left that you can listen to here about her path through life that led her to where she is now. Her contract is for 15 months, but I am going to go visit her in Shanghai for two weeks in November! I've never been to China, so I am very, very excited (and Shanghai is a good introduction without going too deep, although I do hope to do one trip into another part of the country while I'm there). I was just starting to recover from that crazy process and my eldest daughter Beep finally decided to move out with two of her friends into a relatively nearby apartment. That happened last Saturday and it is still a work in progress (although 99% of the move is done now). It went relatively smoothly, but she had a lot more stuff than she thought she did, and it was a really hard job (moving hide-a-beds up from the basement here left some amount of injury, but nothing that's slowing me down too hard... I'm just freakin' exhausted). I'm heading over once I post this to her place for her housewarming party, and will be bringing a couple of serving spoons (she only has a ladle at the moment since her and her roommates didn't coordinate "stuff bringing" particularly well, heh), and a homemade vegetarian pizza to cook (I'm just waiting on the dough to finish and will bring the prepared ingredients in bags to assemble there). Her two roommates are effectively vegetarians (one will eat meat, but only if ethically sourced from personally known farmers), and I think that will be good for Beep (she's a whiz with vegetarian foods, we have always eaten a lot of vegetarian meals at home here). She is also continuing at college (Algonquin) in their Culinary Management programme, where she is learning to be a chef and to be able to run a kitchen or even restaurant. It's a good portable (almost universal) skill to have, and could open up a lot of doors for her all over the world if that's what she decides she wants to do. She is also talking about taking a degree in antropology at university eventually, and that would pair very nicely with a background in food... could be interesting, but we will see. Tuition is now free for low income families in Ontario (that'd be us, give or take a bit), so it is financially easier to go to school for both of them too (I completely missed out on it as it is only starting this fall). Happy had planned to move out at the start of the summer, but didn't quite get around to it, and for many reasons, has decided to stay with me for at least another year of school. She is going into her second official year in the psychology programme at Carleton (with minors in Women's and Gender Studies and Sexuality Studies... she has grown up around a broad spectrum of gender representations, so she is well placed to make contributions in those fields, imho). School starts for both of them in a week, so that's going to take a lot of effort on my part as well (if history is any indication). I do have to say I'm not looking forward to Carleton being packed to the rafters with people again soon, summers are so nice there...

My radio show, The Passionate Friar, is still going pretty well: an hour of feminism/social issues, physics/science, and music... news, reviews, interviews, ideas, engaging audio, and the Oxford comma! I've managed to up my game with interviews this summer and hope to keep the momentum going forward (I need to get more lined up for September now, but I think I will try more phone interviews, so it opens up a lot more possibilities). The shows are available "on demand" for somewhat over a year, so there is lots to listen to if you want to hear the people behind the physics (and science) and feminism (and social issues) you may hear/read about and benefit from. The list of shows to choose from is here on the CKCU web site. It's a long-form show (an hour), with some music for good measure (so it's not an hour of just talking). It gives a chance for people to warm up and share the stuff they are really passionate about and have devoted at least the current part of their lives pursuing. Some recent stuff includes: Ryan Couling and Matthew Johnston about their research into social media reactions to the Jian Ghomeshi trial; the writers for, and the editors and publishers of, the new young adult anthology Brave New Girls: Stories of Girls Who Science and Scheme; Lori Stinson on her research which ranges from patterns of pornography consumption, to corporate manslaughter and homicide laws, to the changing federal family violence initiative; Alex Nuttal on disability tropes in comics and Barbara Gordon /​ Batgirl /​ Oracle; S.M. Carrière about creating characters or talking with/​about people that don't share your lived experiences (e.g. LGBTQA+ if you're not, women if you are a man or visa versa, etc.); neuroscientist turned social worker Dr. Elaine Waddington Lamont; an interview with Canadian new wave synthpop band Rational Youth; an interview and live music with Xave Ruth on the intersection of math, music, and comedy; Dr. Michael Windover, historian of architecture, design, and material culture on his research, exhibits, and book on early radio in Canada; outgoing Carleton University President and Vice-Chancellor Dr. Roseann O'Reilly Runte about her French poetry, writing, and research; theoretical physicist Dr. Thomas Grégoire; science education innovators Martin Williams, Ian Blokland, and Mats Selen (2015 US Professor of the Year); Cindy Stelmackowich on the history of Canadian women in science, engineering, technology, and mathematics (STEM); etc., etc., etc..

Needless to say, every Wednesday morning, my mind is totally blown and I can be excited about life and everything in it all over again. It's good to be The Passionate Friar!!!

Lastly, and on the topic of "mind blown", if you're in Ottawa September 11, please come out to the Carleton University Art Gallery for the vernissage of the art gallery exhibit I helped to curate and produce! It's an amazing collection of artifacts from early women scientists in Canada and tells both the story of the tremendous contributions they made, and the forces that were arrayed against them simply because of their gender. It has been an indescribable privilege to have participated in such a unique exhibit. From the CUAG list of upcoming exhibits:

HERbarium
11 September – 03 December 2017
Curated by Josie Arruejo, Chelsea Black, James Botte, Brigid Christison, Michelle Jackson and Sharon Odell; in collaboration with Dr. Cindy Stelmackowich.

So, what is a “herbarium?” and why is she the focus?

A herbarium is a collection of dried and preserved pressed plants or fungi that are stored, catalogued and arranged systematically for study.

In highlighting the “her” within
HERbarium, this exhibition focuses on the highly skilled and too widely unknown women who contributed to the collection, identification, illustration, production and distribution of early scientific knowledge within the field of botany in Canada.

Because of the accessible nature of botany close to home, and a national pursuit and desire to see, describe and classify flora and fauna species that were distinct from Europe within a then-young Canada, botany was the first natural science formally practiced by Canadian women.

With examples of path-breaking contributions by Catharine Parr Traill, Lady Dalhousie, Faith Fyles, Dr. Irene Mounce and Dr. Mildred Nobles, this exhibition looks back at an important and underrepresented history. It also includes a copy of the “Privy Council Letter, 1920 – Women, Marriage, Employment” which outlines the federal policy in effect until 1955 that prohibited a woman upon marriage from continuing her career as a federal employee. The exhibition also looks forward at the continuing need to encourage women to pursue careers in science, where they face ongoing discrimination on the basis of intersections of gender, race, sexuality, dis/ability and class.

This exhibition has been developed for the Carleton Curatorial Laboratory in collaboration with Dr. Cindy Stelmackowich as part of her seminar “Representations of Women’s Scientific Contributions” offered through the Pauline Jewitt Institute of Women’s and Gender Studies at Carleton University.


If you're there, come say hi! I'll be the old, fat, bald, white guy standing awkwardly in the midst of many very cool and diverse young women ;). I do have to say that it was one of the most amazing courses I have ever taken... when I saw the title of the course, I knew there was no way I could not sign up; however, I had assumed it was going to be more research and essays and maybe classroom discussions. I was wonderfully, wonderfully wrong... it was many, many excursions to the hidden collections of Canada's national museums, practical hands-on work with many brilliant classmates, deeply engaging conversations about women in science (both historically and today), and working far outside my comfort zone on so many things. It was an absolutely magnificent way to cap my B.A. Honours degree in Women's and Gender Studies.

If that doesn't work, and you're here on October 17th... to the best of my knowledge, I should be there for this as well (see above re: potential travel to the UK or maybe even SNOLAB):

HERbarium: Exhibition tour with the curatorial team
Tuesday, 17 October 2017, 7:00 p.m

Please join us for a tour of the exhibition HERbarium, which was co-curated by Josie Arruejo, Chelsea Black, James Botte, Brigid Christison, Michelle Jackson and Sharon Odell, in collaboration with women’s and gender studies professor Cindy Stelmackowich.

Admission is free and everyone is welcome! CUAG is an accessible space, with barrier-free washrooms and elevator.


It does run until December 3, 2017 and I'd be happy to pop by if you get a chance to see it (just let me know a day or two in advance). I will be going in right after my show on Wednesday (August 30, 2017) to lend a hand or two in helping to set up the actual exhibit. It's delightful that we were actually able to get some amazingly rare artifacts to (safely) put on display, including Lady Dalhousie's 18th century personal herbarium, a first edition of Catherine Parr Traill's groundbreaking 1865 book "Canadian Wild Flowers" (a limited print run of 500 units, each with 10 colour plates, hand watercoloured by family members, it was the first "coffee table art book" published in Canada), amazing botanical artwork and science by Faith Fyles, and mycology (mushrooms and fungus) samples and other work by the pioneers in the categorization and study of fungi Dr. Irene Mounce and Dr. Mildred Nobles from the mid-20th century. The reproduction of the “Privy Council Letter, 1920 – Women, Marriage, Employment” (which was the "smoking gun" for so much of what we were trying to document regarding the limitations imposed on women) is just jaw dropping to read.

Just writing that, I feel like I need to go back to bed...

For a video today, hmmm... I think I need to repost something I seem to post every once in a while. The first video, "I Tak Bez Konca" by Polish musician Karolina Kozak is the United States I remember fondly and saw as the possibility of the place. Filmed in Savannah, Georgia, it often brings a tear to my eye (I actually know the people in the coffee shop from when I lived in North Carolina... it's a small world). The second video is the United States that we see on the surface and is the one the world is carefully watching: "I'm Afraid Of Americans" by David Bowie and Trent Reznor (Nine Inch Nails)... which will ultimately win, and at what cost? This is another place where a tremendous amount of my energy is going these days, just wondering if I'll have time to realize that nuclear war has broken out before me and my children and friends are all dead (we live in a national capital). I lived through the 70s and 80s, and I had hoped these days of fear were behind us. They are not, and I think it is even more dangerous (and possible) today than it was then given the multi-axis instabilities and extremism (and by that I mean established governments, not non-governmental groups) we are seeing all over the world. The Bowie/Reznor video sends chills down my spine when I watch it.





If that's too depressing... how about this song from Zepparella's original lineup (I have serious respect [and other feelings] for the drummer, she doesn't mess around when it comes to playing those things):



So much to live for still, let's get our shit together.
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I just got the following email, which reads in part...

I am glad to reach you on behalf of Condensed Matter Physics 2017 Organizing Committee, after having a view at your vast expertise and eminent contribution in the research relevant to Theoretical and Condensed Matter Physics, we courteously welcome you as a speaker for the upcoming Condensed Matter Physics Conference from October 19-21, 2017 in New York, USA.

Hahahaha, ummm, no. Unless they are time travellers from the future and know something I don't about what I'm going to accomplish, I don't think they have anything on me other than my email address ;).

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Received minutes ago...

Dear Phelonius Friar:

I am pleased to inform you that the Senate of Carleton University, at its meeting of June 2, 2017 granted you the following degree:

Bachelor of Science
Honours
Physics
Minor in Mathematics

This degree will be conferred at the Convocation ceremony held on June 13, 2017 at 9:30 am. Please bring your campus card with you for registration purposes. Please visit http://www.carleton.ca/convocation/ for complete details regarding the June 2017 Convocation ceremonies. You may also view the list of medalists approved at the June 2, 2017 Senate meeting. Graduates also enjoy discounts at the Carleton University Bookstore. Please visit them at: http://www.bkstr.com/carletonstore/home for details.

On behalf of Carleton University, I would like to take this opportunity to congratulate you on this important achievement.

Yours sincerely,
Suzanne Blanchard
Vice-President (Students and Enrolment) and University Registrar
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I just got my grade for the last class I had to take (4th year quantum mechanics), and I passed. I did not get the mark I was hoping for, but moving on to a new phase of my life is much more important (it has been so many years of being stressed out of my mind 24/7/365.25, it is going to take me a while to decompress). As such, I will be graduating in June (well, officially before then I presume, but ceremonially in June). I will have a B.Sc. Honours in Theoretical Physics with a Minor in Mathematics. As soon as I get the official word that I have graduated (it is pending now and needs to be approved by the university Senate, along with approvals for everyone else graduating), I will be applying for admission to the B.A. Honours Women's and Gender Studies programme. Having completed all of the requirements for that programme already, as soon as I'm accepted (presuming, of course), I will be applying to graduate from that as well (it will be a fall convocation for that).

Anyone in the Ottawa area is cordially invited to a party at my place the evening of Tuesday June 13th, which is the day of my convocation. I will hold a post-graduation party as well within a couple of weeks of that (probably the weekend of the 24th) for those who can't make it out on a weekday night. Just private message me if you don't know the way... Note: if you ask me for the way to San Jose, then that song will be stuck in my head, and I will hate you ;).
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I just had to open a new package of Nihon Rikagaku chalkboard chalk because I used up the previous package earlier today. I am at home. The professional grade chalkboard is in my bedroom. I am a colossal nerd.

40 hours until the exam that will decide whether I graduate or not. I am studying as fast as my writer's cramp will allow me to (I'm redoing all the problem sets as a study tool and correcting any mistakes I had made as I go). I'm on question 4 of 5 on problem set 3 (quantum perturbation theory) of 6. From problem set 1 to here has already been 26 pages of dense equations, and there's a similar amount to go. I hope to get done today (I figure there's a 50/50 chance), so I can go over my notes and the (shitty... Gasiorowicz 3rd. Ed.) textbook and flag important stuff tomorrow (it's an open book, open notes, open assignments exam... which means it's going to be hard, hard, hard).

Just in case you want to play the home game, here ya go: Quantum Mechanics on The Theoretical Minimum by Leonard Susskind. It's surprisingly easy to follow with a bit of high school math and an open mind (and maybe some alcohol so you're sitting in a Balmer Peak or some such... I've inflicted it on a mathphobic English major friend and they made it quite far).

And, while we're on the topic (nerds, not quantum mechanics)... this is lots of fun!

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Most people have heard about the famous quantum physics thought experiment "Schrödinger's Cat": one places a fictitious cat into a sealed box with a quantum random number generator (a radioactive source that decays very slowly, for instance) and a means to kill the cat should some quantum event happen (e.g. that a radioactive decay happens). The Copenhagen Interpretation of quantum mechanics states that the cat, whose state of being alive or dead depends on a quantum process, is therefore both alive and dead at the same time until someone opens up the box and observes the cat, at which point the universe must decide whether the cat is alive or dead (but not until then). No cat has ever been subjected to this "experiment", but it has been done with subatomic particles and particles do exist in superposition (in many states at once) until an observation is made and cause "the wavefunction to collapse" into one state that, if we observe a short time later, will still be in that one state (presumably if we keep looking, it will stay in that state forever unless disturbed somehow). We are trying to build computers based on this principle now (with some success).

Here is one interpretation of that experiment... things... things don't go so well for Schrödinger or the Cat. Wow, this is pretty messed up stuff... but is great animation and storytelling (and a great and amusing, and kind of terrifying, soundscape)!



Dead or alive? Not Dead or Alive...
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A book. What even... I just don't know...



P.S. Did you know that when you eat a banana it produces antimatter (positrons) inside of you which annihilate with your body's own electrons to produce high energy gamma ray photons (through the well-known relationship E=mc2) that fly out of you (and probably the building you're in... they're way more powerful than x-rays) to radiate the surrounding environment? Now you know.
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This is the first real academic research and writing assignment I ever did, back in 2010. There were a few short essays I had to do earlier in the first year (year long) Introduction to Human Rights course I was taking at the time, but they were just a few pages and leveraged the analysis and integration and writing skills that I had apparently developed over the years (the writing skills were a big surprise to me since I assumed from my high school experiences decades before that it was not something I was good at). They were also not huge jobs. This, on the other hand, was a semester-long 3rd year independent study project on a subject I had no idea about previously (I knew what muons were, and had heard of cosmic rays, but that is about the extent of it). To have been presented with this opportunity in my first year of studies was quite the honour (especially because it would lead to employment over the summer of 2010 and possibly beyond), but it rapidly became clear that I was deeply in over my head both from a subject and skillset point of view. Specifically, writing an academic report is very, very different from any research and writing I had done before, and I was woefully unprepared for what it would take. Needless to say I learned a lot (and got an A-), but it definitely took a toll on my well-being (it ended up being 45 pages and cited 29 works, ugh). I do think it's a good first attempt at something like this, but it does contain some inaccuracies and is missing some fairly important stuff, however it is a good introduction to the topic and I've always wanted to post it here some day (it would have been better if I had MathJax, but I'll just post the images inline as there are relatively few). There are a few bits that I thought turned out quite well, and I can at least be proud of those parts.

Don't let the physics scare you away, I'm coming at the subject generally and mostly in plain English because that's all I had at the time (I do try to do that still, fyi, but I have a bit more knowledge to draw from now and can avoid some of the mistakes I've made here). As a note, completing this project did land me a gig that lasted from the summer of 2010 through the summer of 2013 on three projects related to cosmic ray muons (tomography and solar weather analysis), and formed the foundation for the work I've been doing since with upgrades to the ATLAS detector at the Large Hadron Collider (LHC) at CERN in Switzerland (I've never been there myself, but I've been to TRIUMF, Fermilab, and DESY as part of all of this... and maybe SLAC this coming spring or summer?). A very good friend once claimed that they saw me “living a life of small adventures”, and that does seem to be an ongoing thing.


The Use of Cosmic Ray Muon Tomography in the Detection of Concealed High-Z Materials

I. INTRODUCTION

A. The need for screening

It is becoming ever more important to monitor the flow of goods and people as a deterrent against state, criminal, or ideological organizations that may wish to wage war or cause serious disruption through the use of various asymmetric weapons systems within the territories we wish to consider secure. To that end, increasing surveillance and intrusive inspections have been implemented at points where the greatest risk exists, for instance at airports and border crossings. For an effective deterrent, all traffic through these key points of commerce and travel especially, as well as the appropriate measures for points between, require 100% screening to be maximally secure. For historic and economic reasons, this strategy of complete coverage presents an extreme challenge to even the most affluent and security conscious of societies. Furthermore, any onerous impediment to the efficient movement of goods and people elicits an economic cost of its own that can destroy the very prosperity that such security measures wish to protect.

While it can be argued that the smuggling of conventional weapons poses the greatest chance of occurring and resulting in harm being inflicted through their use, all but the largest of instances of such smuggling into otherwise stable countries are dwarfed by the already existent availability of these items within those countries. Where the national government of a country needs to protect its citizens against all forms of weapons smuggling, it has a special obligation to prevent the use of chemical, biological, radiological, and nuclear (CBRN) weapons against its population, infrastructure, services, and legitimate foreign interests: “Asymmetric CBR threats provide an adversary with significant political and force multiplier advantages, such as disruption of operational tempo, interruption/denial of access to critical infrastructure and the promulgation of fear and uncertainty in military and civilian populations. [...] Proliferation will continue to dramatically increase the threat from the use of CBR agents by states or terrorist organizations against unprotected civilian populations. Proliferation also poses an asymmetric threat against non-combatants outside the immediate theatre of conflict, including Canadians at home.”1 As such, most functional nations have embarked on integrated strategies to minimize the chances of CBRN related incidents. In general, those efforts can be categorized in five ways: supporting or directing the improvement of foreign CBRN control, detection, and enforcement; border CBRN detection equipment and domestic law enforcement training; the securing of legitimate CBRN materials within the country’s borders; improved intelligence operations to detect potential smuggling operations before they occur; and various domestic and international research and development projects to improve overall control and detection capabilities.2

Furthermore, of the CBRN threats, there are emergency measures and possible mitigations that can be taken to minimize the impact to the population and infrastructure of a successful attack with chemical, biological, or radiological weapons; however, the damage that would be inflicted should a nuclear device be detonated in a populated area would be devastating beyond measure to both the fabric and spirit of the country, its operation, and its people. Such results make special nuclear materials3 (as could be used in a nuclear bomb) particularly attractive targets for terrorists4 (“independent” or state sponsored): “Nuclear smuggling is an increasing concern for international security because creating a viable nuclear weapon only requires several kilos of plutonium or highly enriched uranium. The International Atomic Energy Agency has documented 18 cases of theft of nuclear [weapon grade] materials within the last decade, and probably more instances have occurred without report. This is especially prevalent within the former Soviet bloc, where large amounts of nuclear materials are insecurely guarded and inventories are often faultily kept.”5

Of particular concern is the realization that the view, held since World War II3, that the effort required to build a nuclear weapon was prohibitive, is no longer valid. This opinion had been based on the American experience of creating two small nuclear weapons, but it is now widely accepted that the expertise and technical capability to build a viable nuclear weapon is no longer the exclusive purview of large, economically advanced nation-states. In fact, the knowledge and infrastructure required is potentially within reach of any well-organized and funded group with sufficient long-term determination and resourcefulness: “The only real technological barrier to the clandestine construction of nuclear weapons is access to fissionable material itself. There is a growing black market for this material, and eventually demand will result in enough material reaching as-yet unidentified buyers to produce a nuclear weapon”3. In addition to the smuggling of processed special nuclear materials, given that uranium is roughly 40 times more prevalent in the Earth’s crust than is silver6, the smuggling of uranium ore or low quality extracted uranium from such ore is also a more likely possibility.

While it is widely acknowledged that “most known interdictions of weapons-useable nuclear materials have resulted from police investigations rather than by radiation detection equipment installed at border crossings”2, the asymmetric nature of the threat calls for exceptional measures in the effective detection of smuggled special nuclear and radiological materials that might make it past the intelligence operations to a port of entry into the country. Per the U.S. Container Security Initiative Strategic Plan: 2006-2011, “the cost to the U.S. Economy resulting from port closures due to the discovery or detonation of a weapon of mass destruction or effect (WMD/E) would be enormous. In October 2002, Booz, Allen and Hamilton reported that a 12-day closure required to locate an undetonated terrorist weapon at one U.S. seaport would cost approximately $58 billion. In May 2002, the Brookings Institution estimated that costs associated with U.S. port closures resulting from a detonated WMD/E could amount to $1 trillion, assuming a prolonged economic slump due to an enduring change in our ability to trade.”7 While this is a U.S. figure, it can be scaled appropriately to reflect the impact of such an event on any trading nation, or the domino effect such an act would have on global commerce if it happened anywhere.

B. Screening technologies )

1. Radiation sensors )

2. 2D imaging systems )

3. Tomographic imaging systems )

C. Muon Tomography Systems )

D. Outline of Thesis

Because of the sensitivity of Passive Muon Tomography (PμT) systems to high-Z materials (versus lighter elements) they are a much more targeted solution than more indiscriminate imaging systems, and the lack of an active radiation source eliminates the potential health concerns associated with x-ray and gamma ray imaging systems. While PμT systems only address a particular class of risk, specifically the threat posed by the trafficking of special nuclear materials that could form the basis for a bomb or large well-shielded shipments of radionuclides that could be used in a “dispersal” device, the asymmetric nature of the threat justifies the commercialization of this technology to compensate for the serious limitations of existing technologies in this area of detection. Carleton University’s proposal to use large-area drift chambers for muon detection will result in a device that will provide excellent spacial and temporal resolution with very cost effective readout electronics and data processing requirements; however, the initial requirement for a flowing gas in the first generation solution presents a negative offset through higher infrastructure and ongoing maintenance costs that would need to be mitigated as part of a widespread deployment of this particular solution.

II. COSMIC RAYS

A. Overview

Primary cosmic rays are very high energy charged particles (into the range of many TeV24) that originate mostly outside of the solar system, from astrophysical sources, and are comprised primarily of protons (~80%) and helium nuclei (~14%), with the remaining being heavier nuclei such as carbon, oxygen, and iron. These can also interact with interstellar gasses to create a much lower flux of secondary cosmic rays comprised mostly of anti-protons and lithium, beryllium, and boron nuclei23. When cosmic rays interact with the Earth’s atmosphere at high altitudes, they produce showers of thousands of “secondary” particles, usually also called “secondary cosmic rays”. Most of the particles so generated decay or interact with atmospheric atoms before they can reach the surface of the Earth; however, a shower of gamma rays, electrons, neutrons, and muons24 (due to relativistic time dilation) do reach the lower altitudes of the atmosphere and the surface itself. Of these, the cosmic ray muons are of primary interest in this application due to their high energy, penetrating power, and the relative ease that their path and momentum can be precisely determined.

B. Spectrum and properties )

C. Multiple scattering and tomographic analysis )

III. Detectors

A. Overview )

B. Drift Chambers )

1. Basic Operation )

2. Specific Topology )

3. Readout Electronics and Data Processing )

C. Scintillation counters )

IV. Implementation

A. Description of prototype project )

B. Readout Electronics )

V. Further exploration

In addition to the use of the proposed muon tomography systems in border security and container/vehicle inspection, the basic technology can be useful in other applications as well. Furthermore, with appropriate research and development, enhancements to the basic technology are possible that will reduce the total cost of ownership and operation.

A. Use as a scientific instrument

With the possibility of large area muon detectors being deployed along borders and in key strategic locations, it should be noted that each one of these devices can be used as an element in a larger cosmic ray observatory. The information on incident angle and momentum of incoming cosmic ray muons could provide a wealth of data to astrophysicists and particle physicists alike (who can analyze the data against various models developed for subatomic phenomena to support or discard various hypotheses). One major issue is that data on the contents of scanned targets cannot be shared with the general public due to security concerns. This can be addressed by sending data only when a scan is not in progress. Alternatively, if the initial momentum (before interaction with cargo) is reconstructed by projecting the final momentum backwards through the gathered tomographic data when cargo is present, there will be no way to determine anything about the contents of the scanned cargo from the data. In any case, the angular information from the top pair of detectors is gathered before any interaction with cargo and should not present any security risk as it is a purely astronomical data source at that point.

B. Developing a sealed chamber (no gas flow)

The major disadvantage of the drift chamber solution proposed by Carleton University is the need for a flowing gas mixture. If it were possible to seal the chamber and operate it for long periods without needing service, then it would be both cost effective from a readout electronics perspective and from the longer term operational cost and complexity perspective through the elimination of the need to manage gas supplies and disposal. Much work has been done over the years on sealed gas ionization based detectors, and research and development in this area could have a large impact on the cost of muon tomography systems in the field.

C. Use of active muon source system

One of the issues with using cosmic ray muons as a source of radiation for tomographic purposes is their relatively low flux (1 muon (cm2 min)-1). This low flux means that it takes at roughly a minute for a basic scan to determine whether there is any high-Z material of concern. By using an artificial source for a higher muon flux, it could be possible to do the scans faster or to build a more complete tomographic image of the contents of a shipping container or other target of interest. The issue is, of course, that this introduces a vary dangerous ionizing radiation source to the situation and the lack of any additional radiation is one of the attractive elements to using cosmic rays muons as the probe.

D. Use in sealed-container inventory determination and management

There are many installations, for instance Chalk River in Ontario, where there are sealed containers with unknown quantities of potentially dangerous materials in them. There are also situations where contents of containers are claimed to contain certain materials, but need to be verified as part of nuclear control treaties. In those cases, cosmic ray muon tomography could provide an excellent tool for cataloguing and monitoring the contents of these containers. Since this is more of an audit application, the lower flux and time to acquire the necessary level of data are not as much of an issue as for applications that impinge on commerce.

VI. Conclusion

Passive cosmic ray muon tomography systems present an excellent solution to the issue of deterring and detecting the trafficking in nuclear and radiological materials – in the first case through direct detection of high-Z materials, and in the second case, being able to detect high-Z shielding that might be hiding lower-Z radiological materials. The system further distinguishes itself by not introducing any new sources of radiation, thus sidestepping any potential health or safety concerns from the public or business. Carleton University’s proposed drift chamber muon detectors build upon decades of experience in implementing high resolution muon analysis systems, and can be used to determine to a high degree of accuracy both angular and momentum data on the muons passing through a detector system for analysis by the tomographic software. The low cost of readout electronics compensates for the higher cost due to the requirement for gas-filled chambers, and will result in a competitive solution for field-deployable systems.

VII. References )
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Welcome to 2016, and Happy New Year! Out with the old and in with the new: after 5 years (!!!) on the radio, The Dollar Bin and my follow-on attempt at a show Doing It On The Cheap are no more, but please welcome The Passionate Friar to CKCU’s airwaves. Same host, same timeslot, but a (hopefully) very different show. Sandwiched as it is between talk programming (The Tic Show... err, Wednesday Morning Special Blend, and Hans’ CKCU Literary News) and music programming (Permanent Waves with Erik Stolpmann), the show aims to make that transition over its hour. It will start with a chat, some news, and sometimes interviews on the twin (and generally, but not entirely, exclusive) topics of feminism (and social issues and social justice) and science (the backbone of our civilization, with an emphasis on physics, the most fundamental science) — both of which are the subjects of undergraduate honours degrees that I am working on at the moment (a year and a half to go, ugh). There will be some music between the talk segments at the start, and the show will transition to just music by the end... found music mostly, where I will play music that I did not specifically set out to find, but have wandered across anyway (in that regard, The Dollar Bin lives on). P.S. I’m looking for correspondents on all three topics (feminism, science, and music) going forward, drop me a message if you are interested!

From the show’s new home page (this will be the blog associated with it, that was easy):

A gently curving corridor full of pipes and cables -- a photo of the decommissioned HERA accelerator ring at DESY in Hamburg, Germany

An hour of feminism/social issues, physics/science, and music...
News, reviews, interviews, ideas, engaging audio, and the Oxford comma!


This is a show for everyone who is passionate about more than one thing, and anyone that loves the simple, small joys of forever encountering new ideas, and having new experiences. While specific passions are going to be presented — simply because it is what moves this Friar in the moment, oh and time limitations, let’s not forget that — the intent is to do so in a way that is accessible to all, to get your creative juices flowing, to make your day more varied, and hopefully even provide inspiration for whatever your particular passions might be.

While what is presented here will truly be only the tip of the iceberg for this Friar’s passions, and the passions of those whose voices and works and actions are featured, the topics are sufficiently broad that it will take years to even get started exploring them. Specifically, this show will be focusing on three primary subjects: feminism and social issues, physics and science, and music and more music. Where, along with a foundation in feminist studies, comes the more general topics of social justice, aboriginal issues, issues of migration and human rights, intersectional identities (don’t worry, terms will be explained as we go), LGBTQ+ issues, globalism and neoliberalism, accessibility and disability issues... the list goes on — in short, social issues in general will be covered. And then way over here, we have the so-called natural sciences, which study the natural processes of the world around us and provides the underpinnings needed for the successful development and deployment of technologies, which then forms the functional backbone of our many societies. There will be an emphasis on physics because it is the most foundational of the natural sciences, but not a single field of science does not touch us somehow in our day to day lives: biology, chemistry, Earth sciences (geology, meteorology, ecology, oceanography, etc.), space sciences, and again the list goes on.

Why feminism and physics? Well, the simple answer is that I am in my last year and a half of independent honours degrees in both of those subjects: officially, I’m working on a B.Sc. Honours Physics (Theory Stream) degree, but I have also been collecting all the credits I need for a B.A. Honours Women’s and Gender Studies degree (I should be done that process this year, where I will not be done with physics until 2017, sigh). I came to Carleton as a “mature” student to finally study physics after a career designing and building electronics and software, and doing international project management on technical projects, while raising my children as a mostly single parent (by far, the hardest thing I’ve ever done... they are adults now, which is why I was finally able to go to university for the first time). Decades ago, I had a flash of inspiration/realization that synthesized much of what I read about the nature of the universe. I assumed I was wrong because I was ignorant in some critical way about it, but the more I read, the more it looked like I might be onto something, and the more evidence there was that there was value in the approach I had envisioned. I further assumed that someone else would come up with the same approach, but that apparently didn’t happen either, thus when my offspring were old enough, I quit my (very well paying, waaaah) day job and became a full-time student (mmmm, Kraft Dinner, sure I’ll have another bowl). The summer after my first year I took a course that aligned with several of my other passions: Feminist Disability Studies. I was hooked. Badly hooked. I have always been a social activist, and this wasn’t my grandmother’s feminism: it was new and exciting and inclusive and raw and full of dangerous pitfalls and irreconcilable differences. I took all manner of feminist studies, indigenous studies, language courses, and political science courses, and one day went into the Women’s and Gender Studies Department where they stared at me like I had two heads and announced that I was, randomly, most of the way to a minor in the subject. By taking the remaining courses for the minor and one more core course, all I needed to do was chip away at getting qualifying feminist studies credits in parallel with taking my physics degree (which was taking me longer than I had planned... that stuff is hard!), and I ended up with enough credits for a full major, and then an honours degree. I can assure you that nobody is more surprised than me! Due to university regulations, I need to graduate from my physics program before I can apply to the women’s and gender studies program, but I will just need to sit around with my thumbs up my butt and wait for the end of that semester because I will have all the credits I need already (okay, I won’t be sitting around, I’ll probably be doing physics research, but I won’t need to take courses).

Music? Well, if there is one language that is shared by all people, it is the language of music. Music is also at the core of everything I do (yes, including physics). Over the course of five years of doing The Dollar Bin on CKCU, I have learned much about how to find and present found music. For the most part, the music I played on the show was on CDs I had purchased for $3 or less in “dollar bins” wherever I travelled, and were by artists that I had never heard of before. Every show was the presentation of the outcome of the series of adventures I had listening to these previously unknown-to-me artists. I blissfully ignored genre boundaries and mixed music of all styles and origin and time period to create (what I have been told by others) was a challenging and engaging hour of music. Some of the songs I will be playing will be specific to topics I will cover, but I will continue the strong tradition of bringing intriguing found music to the airwaves (without the limitations I imposed on myself with The Dollar Bin — it’s all fair game now!).

Feedback is always welcome, along with music and topic ideas (especially if I can interview you or you can suggest someone to interview). I am also looking for correspondents (every/anywhere, and every/anywho) to do research, interviews, and produced segments on the topics covered by this show. You can reach me at dafriar23@gmail.com.

Don’t Let A Label Silence You ... a feminist activism project at Carleton University

Photo credits... Top: “In The Body Of A Dragon”, a view of the curving tunnel of the decommissioned HERA superconducting particle accelerator/synchrotron at the Deutsches Elektronen-Synchrotron (DESY) in Hamburg, Germany. Photo by me, 2014. Bottom: “Don’t Let A Label Silence You”, a student group feminist activism project I participated in on ways to destigmatize mental health issues done as part of the Activism, Feminisms & Social Justice (WGST2801) course at Carleton. Photo by me, 2013. As a note, the radio segment done with my classmates as part of that campaign (we took over The Dollar Bin that week to do it) ended up with the, now defunct, CKCU feminist radio show Femme Fatale being created by one of the participants, Lilith (they had never heard of CKCU before then).
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Well, I've written both my exams for this semester. I think I did okay on the first one, but did pretty poorly on the second (almost no time to study for it and it was less than 24 hours after the first one I wrote, I was exhausted walking into it). I went into the second one (Numerical Analysis... really the mathematical analysis of numerical analysis techniques... so Meta, Even This Acronym) with a 91%, but the exam was worth 50% of my mark so I don't expect to walk away from this course with an A unfortunately. <rant>This sort of thing really underscores the failings of the university system as it stands: it's an adversarial system designed to challenge you under unrealistic conditions. I mean, think of it this way: when am I ever going to be trying to do, for illustrative purposes (it applies to almost all courses like this), numerical analysis on an island cut off from the rest of civilization and all reference material under a strict time limit? Let me tell ya, I'll be gathering food and building shelter first, not setting error bounds on discrete numerical algorithms that approximate the solutions to ordinary differential equations. Just sayin' (although that probably makes me a good person to have along in an emergency situation). In short, I'm being judged on my ability to perform in unrealistic conditions that I will never experience again as long as I live — reasonable only for contestants of Japanese and Spanish game shows</rant>. Anyway, I have to finish an English essay (!!!) and then I'll be done my semester. It might be as early as today, definitely tomorrow at the latest.

Anyway, I went through another of those World Science U lectures, this time "The Accelerating Universe" with Nobel Prize winner Adam Riess. Gotta say, this one was a real dud for me, although your mileage may vary. He really looked like he didn't want to be there (and some of his quips support that notion), and I came away with the impression that I didn't really sympathize with him... his presentation left me without an empathic impression. Weird. The material was okay, but was mostly just a rehash. The best part was when he talked about all the other ways research in so many diverse areas (besides the work he did using supernova to calculate how far away distant galaxies were) completely agree with the result that his team came up with. Spoiler alert: we know nothing at all about 95% of what the universe is made from (and this is a result that has only been known for about 20 years, it's a freshly-minted puzzle and probably one of the most breathtaking results of modern physics). He did make a fun little joke about science presentations though when he was showing images taken with the Hubble telescope of supernova in distant galaxies: "How do we find them? An average of one occurs per galaxy in a hundred years, so we just watch tens of thousands of galaxies at once and we see them all the time. All you need to do is look at images, and if you see big yellow arrows like this pointing at a part of the image of a galaxy, there's usually a bright spot at their tip, and that's the supernova!". Heh. I think the thing that really stood out as being different in this overall package is that the lecturers have little clips that answer a particular question (their purported "office hours"). For the other presenters I've seen, they spend a fair amount of effort to craft a good answer, but Riess' answers were only a few seconds each and didn't really constitute a full discussion on the (brief) subject [conversely, Spiropulu went on a bit long in these sections I thought, but I did appreciate all the information she conveyed]. The questions were also pretty cut and dried (almost yes/no answers), and didn't really add to the presentation.

It was only within the last hundred years that we've learned the universe is expanding. What do you think we'll learn about the universe in the next hundred years?

I think we will figure out why it is expanding and why that dynamic is changing (yes, dark energy, but what is it?). We have been very good about describing the what and in many ways the how, but we still don't understand the underlying causes that produce the features we observe.

One of Einstein's great contributions to astrophysics was the idea of a cosmological constant — but he formulated his ideas in the context of long-held assumptions about the universe, which turned out to be false. Technology, in his time, was holding back deeper truths about the universe. Do you think the same can be said today? Will we upend some of our fundamental beliefs in science once technology advances significantly?

Well, considering that we really only agreed that there must be dark matter in the 1970s (even though it was found earlier, but nobody was convinced), and dark energy in the 1990s, and both of those discoveries happened because of advances in observational and data processing technologies (which, in some senses is the more important of the two due to its general purpose nature), there is no reason to suspect that our understandings won't be shaken over and over again as long as we keep looking with better and better technologies.

Adam Riess's team of scientists was famously in competition with another group that ultimately came to the same conclusion about the existence of dark energy. What do you think about competition versus collaboration in science? Does one impact scientific advances more than the other?

Collaboration certainly impacts discovery more than competition ever could; however, competition makes for better science -- and by better, I mean that the results are improved in quality both before they are shared (to avoid looking like idiots... or "dumbasses" as one of my profs used to say) and that they can be independently verified and/or critiqued (usually a bit of both). An excellent example of this are the CMS and ATLAS experiments at the Large Hadron Collider. These two huge collaborations (that developed and built each detector independently, so one error in design or construction of one should generally not exist in the other) are in competition with each other, so if one team announces something and there's no "signal" at the other detector, extreme care needs to be taken in accepting the results. In the end, it tends to be more of a friendly competition than a cut-throat "winner takes all" attitude, so even though it's a race to results, knowing the other team is there to make sure that good science is being done is a huge benefit to the teams and to the public.

In this Master Class, you've learned a staggering concept: roughly 95% of our entire universe is in a form that is essentially unknown to us. Given that science has certainly taken profound strides in understanding the universe over the past few centuries, how does this realization affect your view of our state of knowledge?

Well, I've lived through the evolution of this knowledge, including when it was still not corroborated from so many sources, and I actually take comfort in knowing that we really didn't know as much as we thought about the universe (things were looking pretty tidy after the Standard Model finally settled down). Like the transitional period from "classical" physics to "modern" physics, I think we may be going through another such transition in understanding. I can't wait to see what this all turns out to mean!

And, for this underwhelming performance, this post gets Har Mar Superstar's pet store dance video (Note: completely PG, but what has been seen cannot be unseen). As I post this, I hope I never meet Dr. Riess if he ever sees (so astronomically unlikely) this post... he strikes me as having a biting wit that would probably leave a mark on yours truly ;).

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And we are back into heady territory with Maria Spiropulu's Master Class "Nature's Constituents". This is a course on pretty much everything we know about how the universe functions at a subatomic, particle physics, level. It's a bit more dense than the other sessions I've done, but I have to say that I actually learned stuff in this one (important stuff for me even) that I did not know about before. In particular, her discussion of how a Higgs field was discovered on someone's desktop in 1981 was quite an amazing side topic (for realz... not the Higgs field we built the LHC to observe, but a Higgs-like field in a laboratory setting, very cool stuff... was pretty much forgotten about until all the fooferah about the Higgs particle discovery, and has since been dusted off). One of the things I like about her presentation is she's not afraid to say, "well, we have no fucking idea whatsoever"... which is the utter truth in that regard. She's also very brave in suggesting that the LHC may find the lightest hypothesized supersymmetric particle in this current run (which would be even more revolutionary than having found the Higgs as this would be completely new physics). Here's an intro video for more info... it's pretty mind-blowing stuff (but pretty straightforward to understand as a concept). If supersymmetric matter exists, it might explain the fact that most of our universe is made of stuff we can't observe and know almost nothing about (except that it's there and affects things gravitationally, and is causing the expansion of our universe to speed up).

Do you think we will ever be able to comprehensively describe all of nature in a single elegant equation? Why or why not?

I do not think that is possible due to the existence of chaos. Given that we cannot analytically solve systems that contain more than two of anything (the famous "three body problem", where there is no general solution to these classes of systems), to suggest that we can come up with descriptions of anything but the simplest of systems (luckily, some quantum systems like the Standard Model qualify) would require a revolution in our ability to express these systems mathematically (and even then, we have proven that past a certain complexity, some mathematical forms are unsolvable with all the math we currently know). With that said, there is obviously some underlying structure to our universe that we have not yet discovered that will provide the connection we need between gravity and what we know of the phenomenology predicted by the Standard Model. That the Standard Model is parametrized is a glaring recognition that we don't know the "why" behind the model (it just works startlingly well when applied). Understanding how the parameters arise is definitely something I think we will eventually figure out, but that only gets us so far. Can the existence of baryons and bosons ever say anything about the nature of a flower or the latest pop song? Looking for an equation for "all of nature" is too grand of a question, but finding out "everything" about the constituents that make up these phenomena is certainly something that we will be able to describe some day. A single elegant equation? Maybe not that (the days of analytic solutions may be coming to an end, all the "low hanging fruit" have been picked), but we will at least come up with reasonably simple models that we can solve numerically with ever more powerful computers.

I saw a post in the comments that I felt the need to answer as well (for myself more than anything): i can't perceive the difference between the notion of "luminiferous aether" and the "Higgs field"?

The main difference, from my understanding, is precisely that: perception. The aether was proposed as a preferred inertial frame that all motion was relative to (including light). As such, you would be able to tell whether you were at rest or not by measuring changes in the speed of light based on what direction you were going relative to that light. Einstein's stroke of genius was stating the obvious (based on experimental evidence even, the Michelson-Morley experiment for instance) and running with it to find out what it implied, and it says that the speed of light is the same to all observers no matter what their state of motion, so such an aether cannot exist. The Higgs field does not provide any kind of reference or directionality, and thus can only be detected by setting it "ringing" with the injection of massive energies (thus forming Higgs particles, which we can detect the decay products from). Particles that can interact with the Higgs field acquire mass from that interaction, but whether the particle is here or over there, or standing still from my perspective or moving at nearly the speed of light relative to me, the Higgs field must obey the principle of relativity. What that means is that if you have a particle in front of you, not moving, it will couple with the Higgs field in a particular way, but if you take that same particle and accelerate it to nearly the speed of light, the Higgs field has to couple with it in exactly the same way as it did when it was at rest relative to you. To illustrate this, pretend you could sit on the particle as it accelerates to tremendous speed relative to the Earth... to you and the particle, you are sitting perfectly still and the Earth is moving away at tremendous speed... since you are "at rest" from your perspective, the Higgs field couples exactly as it did before you accelerated relative to the Earth and the mass of the particle from the Higgs coupling, from your perspective sitting on it, is exactly the same as it was when it was at rest in front of you before it zipped away. This is how the aether and Higgs field are fundamentally different notions. Caveat: I'm no expert, this is just my understanding, I could be wildly wrong about the Higgs field (but I'm pretty sure about the aether part, heh).

In many of the other Master Classes, you've heard theorists describe how they try to understand our natural world. In this Master Class, you've learned a bit about how an experimentalist goes about the same task. Which do you find yourself more inclined to, the theoretical side, thinking up new science to explain phenomena, or the experimental side, being hands-on and trying to discover incredible evidence?

Getting personal, eh? Well, I have a lifetime of experience doing practical/experimental stuff (hey, a roof over my head and food on the table is important to me), but my personal interest has always been more on the theoretical side. I like to think that having a grounding in the demonstrably possible provides for the possibility that theories I might come up with are eventually testable. I think we do need people that are focused on theory and many times more that are working on experiments, but I see it as a spectrum rather than a binary choice, hopefully with those who are extremely one way or the other being outliers on the curve. Being able to communicate between the two domains is critical for progress to be made. I should add that communication skills are key to being able to keep doing science, because without it society will lose interest and eventually take its resources somewhere else.

The Large Hadron Collider is one of the biggest scientific undertakings in all of history. It is estimated to have cost somewhere around $13.25 billion (USD), including operating costs of about $1B/year since it became operational in 2008. Do you think that's money well-spent? (I actually think this was a pretty good answer, btw)

The first thing to realize is we didn't take 13.25 G$ and set fire to it in someone's back yard for a barbeque, it was paid to research institutions, manufacturing companies, services companies, government departments, and the salaries of tens of thousands of scientists, engineers, project managers, highly skilled tradespeople, and general labour ... all over the world. All of the capabilities developed to build and run the thing, all of the innovations created to solve problems we've never faced before, all of the infrastructure put in place to support it (including network infrastructure as well as industrial and intellectual infrastructures) have returned on that investment since then, and will continue to do so for decades to come. As a bonus, we get to pursue fundamental questions of existence (and as a double bonus, it was money that wasn't spent developing ways to murder other members of our species with new and more efficient war-making capabilities). All in all, to me, it seems like a pretty good way to have spent that money.

In this module, we've learned about how ideas from condensed matter physics were able to inform particle physics. Do you see so-called "cross-fertilization" as being something that has to happen again and again in science in order to deepen our understandings of the natural world?

It doesn't need to happen... brute force and ignorance (and lots and lots of money) could win the day, but I don't think too many people want to take that route. To that end, cross-fertilization (multi-disciplinary exploration) is a powerful tool to figure out new ways to search and new places to look for interesting phenomena related to the many questions we know are trying to answer (or for ideas on what questions we should be posing, and how). The main problem is there are so many silos of information with so little cross-communications. In some cases, it's from people wanting the power that comes from control of information; but in most cases it's simply the truth that people are so busy with just trying to do what they have to do that there is no time to pursue what they want to do (presuming they want to do this sort of information sharing and synergizing). In that regard, physics is no different than most other professional pursuits. I find it fascinating that "Higgs" (Higgses? Herds of Higgs? ... need a new plural form for non-boson Higgs-like entities, heh) were created back in the early 1980s, but that fact was lost until the publicity frenzy around the Higgs particle discovery. I wonder what insights could have been applied to the search for the Higgs boson if that line of inquiry had been pursued actively since then (35 years is a long time, and much could have been discovered)? I strongly believe that developing "desktop analogs" of quantum and/or cosmological systems provides an excellent way of having many more eyes and hands and inspiration devoted to answering important questions (one of my favourites of these recently is the production of black hole optical analogs in Bose-Einstein condensates... a much safer endeavour than trying to make black holes large enough to study carefully over long periods of time).

In April 2015, the LHC began its second run, with collisions at much higher energies, as it searches for (among other things) the long-sought supersymmetric partners. But what if we don't find any new particles at the expected energy scales? Would you advocate for building an even bigger machine to search for them? Or is it time to spend that money elsewhere?

There's some talk that perhaps colliding baryons is too sloppy for precision physics and we need to build a massive electron/positron collider (the ILC). Certainly if the LHC can be upgraded, it probably should be (rather than scrapped in favour of something like the ILC... much like so many facilities were scrapped or nearly scrapped when everyone's money was put into building the LHC in the first place). So yes, I see value in upgrading the LHC (especially since it can also accelerate large nuclei) and I don't think that conflicts with building the ILC as well (which last I heard will be in Asia, possibly Japan... there seems to be no stomach for it in North America at least, and Europe has CERN).

Hmmm... video posting this time around? Hmmm... Going to go far afield for this one and post one of my favourite songs/videos by FKA Twigs (nothing to do with physics, but she certainly uses a lot of it in this video with seeming natural giftedness, heh).

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You can tell that I need to be focusing on studying and finishing my last essay for the term, because I keep finding amazing things to do that is not studying and finishing my last essay. Today's reason for turning off my computer (I'm this close) is World Science U. This new site currently features a pair of courses by popularist and educator Brian Greene on Special Relativity (both as an introduction for the generally interested, and as a course heavy in math, but doable by anyone with a high school eduction), a series of "Master Classes" by a number of renowned researchers (in math and physics, but also biology and neuroscience and the nature of consciousness), and a grab-bag collection of "Science Unplugged" short presentations on many questions that people ask about science topics (as they say, "Unscripted. Uncensored.", heh).

The fatal blow for me (fatal blow to my studies productivity) was that they had a Master Class by Andrei Linde, whose ideas are very much part of what led me (forced me?) to abandon my life as a well-paid systems engineer and learn to love Kraft Dinner as a first-time undergraduate student. Sigh... with the promise that the whole thing could be gotten through in a couple of hours, I was up until 5AM this morning (which was only a couple of extra hours of being awake, I had already been working late). So... I took and completed Andrei Linde's "Universe or Multiverse?" Master Class earlier, and now I'm behind on my studies (and writing this blog post to boot). As a note, the lectures are very accessible, and the only math equations he throws up on the screen are just to show their form in comparison to another equation, one does not need to understand what they mean exactly or how to solve them. After each video, there was a fairly pointless "quiz" (multiple choice, completely unchallenging/un-helpful, but I guess shows you actually watched the video), and then you needed to leave an opinion comment on a discussion board to a question they asked. That is the purpose of this blog post, to preserve my answers over here... I present the question, followed by my sleep-deprived answer for posterity (or posterior, depending on your opinion of such things). What I thought particularly noteworthy is that my answers at the end of one section seemed to predict what he would talk about in the next section (which I hadn't watched when I was answering), so I have at least some understanding of the topic (or I've read enough Linde that I know where he's likely to go). What was also fun about the lecture videos (there were only four of them), was that he started out pretty deadpan in the first one and by the third was making very wry (and very Russian) jokes and humorous comments about what he was presenting.

The inflationary theory has been able to provide answers to many questions that were previously thought to be outside the purview of science. Yet, even though our fundamental understanding of the evolution of the universe has progressed significantly, we seem no closer to resolving various key issues, like "What was before the Big Bang?" Do you think we will ever reach a full understanding of questions such as these, or will our progressions in science only expose new unanswerable mysteries?

Two things come immediately to mind: that it is current thinking that we really only know anything about 4-5% (depending on who you talk to) of what the universe is made of (we know nothing about so-called "dark matter" or "dark energy", which comprise 95-96% of the energy content of our universe), and that Planck Energy scales are on the order of 1030 eV (where the Large Hadron Collider can explore into the 1015 eV range). That's a lot of room left to discover things. There is also the historical precedents that as new science stabilizes and is understood, there are always seemingly "little" things that remain unresolved that when looked at become entire new branches of science (and demand new branches of mathematics). So, we will never reach a full understanding of our universe, but we will continue to peel away layers to expose new mysteries... which may be answered in time as well, but are unanswerable in their day.

In the multiverse, different physical regions are so far apart and independent that residents in a given region might not ever even be capable of finding direct evidence that any other regions exist. What do you think about the burden of proof in this situation? Do you side with those who say the theory is impossible to disprove, or impossible to prove? Or do you land somewhere in the middle?

This questions is reminiscent of the Smolin vs. Susskind argument about whether there was any merit to the notion that our universe is the way that it is because if it wasn't we wouldn't exist the way that we do (the "anthropic principle"). Another form of the argument is that we live in a part of a multiverse that has the parameters needed for our visible universe to exist the way that it does and perhaps other sections of the multiverse (in different states or having experienced different conditions of ongoing formation) could not look the way our universe does (again, it's the anthropic principle: we see what we see because if it wasn't this way, we wouldn't exist in the particular form that we do). I am hopeful that there will eventually be some higher order prediction that we might be able to observe that could only be the way it is if our universe had been in contact with another universe (let's say) at one time that evolved differently from ours. Since inflation as it stands is still a relatively young notion, I think it's possible that we will ultimately come up with a way to at least place limits on what the initial conditions of our universe looked like. Another possible angle is if our universe came into being on the remains of a previous universe, perhaps there are traces we could find in the structure of ours that hint that there may be some existing foundations upon which our edifice was built over. In brief, if our universe ever had an interaction with another part of the multiverse, there should be some trace.

In 1973, physicist Brandon Carter introduced the idea of the anthropic principle. While there are many variations of the principle, they mostly hinge on the idea that there are many universes and that physical laws can vary from one universe to another. In some universes, the physical laws are hospitable to life as we know, but in some universes they’re not. In seeking an answer to why the laws we observe have their particular form, anthropic reason replies that there is no first principles explanation — the laws can and do vary from universe to universe. We see our laws we do because had they been different they’d be incompatible with life, and so we wouldn’t be here to observe them. Do you find this convincing? Circular? Do you think anthropic reasoning has a place in scientific thinking?

The anthropic principle is simply a version of "it just is", which is not a very satisfying argument to me (even though I think it is correct). One of the fascinating things about Linde's explanations is that it goes a little bit further to suggest "why it just is" (why our universe seems to be so suited for our existence). Ultimately, it is true that if there is no scientific mechanism to prove or disprove a theory, then it is just a philosophical argument with no scientific merit; however, at least this principle does pose a question that begs investigation. Even if we can't prove (or disprove) the anthropic principle now, simply proposing it starts a conversation and perhaps some day, some very clever experimentalist will figure out a way of giving it a poke and seeing if there is some substance to the notion. As Linde stated in an earlier lecture, he once would not have believed that the BICEP2 instruments were possible, but gravitational waves were posited and someone eventually figured out a way to build an instrument that might be able to see them (indirectly) if they existed.

One can argue that our universe appears to be finely tuned. For example, had the energy density in the early universe been much lower (and negative), the universe would have rapidly collapsed; were it higher, the universe would have expanded so quickly that galaxies would have never formed. Is it asking too much of science to explain such features? Should we accept them as lucky accidents? Or, as some would argue, acts of divine providence?

Explaining such features is exactly why science exists. Will we be able to answer these seemingly ultimate questions through science? To presume otherwise is doing a grave disservice to our collective ability to find answers; however, to presume that we must be able to find answers to these (and all later) questions sounds like hubris to me as well. Often, it just turns out that when we can't answer a question it is because we have asked something nonsensical and need to go through a long and difficult process to realize what questions we should actually be asking (writing that, I thought of the fictional story Hitchhiker's Guide to the Galaxy... where they found The Answer to the universe, but eventually realized they didn't know what the question was). So far, new ideas and their subsequent refinement has been able to produce very powerful tools and models to describe so many of the phenomena we see and can measure. Eventually there will be a breakthrough that we can't foresee now that will give us new insight into what new questions we should be asking (sometimes modelling things with laboratory systems that we do not have the ability to observe directly gives us the insights and/or proofs we need... for example, using Bose-Einstein condensates in a lab to mimic some of the predicted behaviours of black holes). Perhaps these new questions and answers will eventually lead to answers to these very large (very likely refined-over-time) questions.

In this Master Class, Prof. Linde remarks on the challenges in proving the inflationary multiverse. If an infinite number of different universes can be produced, each with different laws of physics, it seems impossible to design an experiment that could falsify the theory. In a given era, is it acceptable to say a theory is wrong if we cannot conceive of a way to prove or disprove it? Should a theorist simply follow their intuitions when no measurable data might be forthcoming?

If that intuition can provide potential insights into why something might be the way it is, then there is tremendous value into pursuing that line of thought. Intuition is how breakthroughs are made, but it still has to survive criticisms leveled against it to continue to be a valuable idea. Just like intuition can suggest a solution to a problem (even when it can't be tested in any way that we current know), there are others who can apply their intuition to figure out ways the original idea might be wrong, or how it can be made more robust. The worst case scenario is that an internally self-consistent fiction is constructed that turns out to be utterly wrong, but Linde's argument that to unseat a potentially faulty hypothesis requires that a better hypothesis be put forward is a good one. If nothing else, currently unprovable theories challenge those that are bothered by such things to figure out something that can be tested (or ways that the theory might be disproved conclusively or at least seriously limited).



A note on the video: sadly, the BICEP2 results were contested due to new data from the PLANCK satellite (which had not been published at the time of this result), but it doesn't necessarily say that the results were not observations of gravitational waves, but that we can't be sure that's what we're seeing (it could also be polarization from the fact that there's more galactic dust out there than we thought, which is what PLANCK observed). I think it's a good intro to the kind of person Linde is though anyway: observe that he states (even though he was told the results were unassailably true), "if this is true"... ;).
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I have been ever so gently brushed with the most peripheral of emanations from the recently awarded Nobel Prize in Physics by my presence at Carleton University (and the fact I just recently visited SNOLAB where the science happened... with Dr. David Sinclair himself, no less, as our "tour guide"). Here's some links and a few more pictures I took on that trip:

http://www.nobelprize.org/nobel_prizes/physics/laureates/2015/press.html

http://carleton.ca/our-stories/story-archives/nobel-laureate-thanks-carleton/

Dr. David Sinclair, founder of SNOLAB, expounding in SNOLAB:



A look down into a new working area. SNOLAB is already a cleanroom, but smaller temporary ultra-clean cleanrooms are sometimes set up within it for specific experiments (often for cleaning and assembly of sensitive components). You can see one here (the tent-like thing) and another that was open but could be made into a cleanroom again if needed. For scale, those are full height grey storage shelves toward the top of the photo, and a workbench to the left (the green hose thing on the right of the photo above can be seen on the bench in this picture... it's taken from pretty high above). One of the experiments we saw being worked on there was DEAP, an experiment that will be looking for direct evidence of dark matter interactions (a thing we know almost nothing about, and have never observed, but which seems to make up 27% of our universe).



This photo is a reminder that SNOLAB is 2km underground. First, the white coating over the rocks is to keep the dust and small rock fragments from falling into the laboratory that is cut out of the rock. The yellow plates (which are everywhere) are terminators for huge cables that were driven deep into the rock surrounding the human-made caverns, and that keep the surrounding rock under tremendous tension so it doesn't just relax and collapse in on the hole we have dug to work in. Apparently if the blowers ever stop for maintenance, you can sometimes hear rock quakes (and sometimes even with the blowers going). I have been told it is one of the most terrifying things a person can experience.

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Remember how I said I spent my summer in 2014 chained to a radioactive block of concrete for three weeks? Well, I exaggerated... I wasn't actually physically chained... I spent every waking moment there of my own free volition (most of it really exited to be doing something so amazing) to help see that the project we were working on (PDF) gave us the data we needed. It was months of intensive preparation to get there, and what was supposed to have been a part-time consulting role for me turned into a key role with the data acquisition setup for the project. For all that it was certainly a highlight of my career so far as a physicist (and pretty much one of coolest things I have ever done in any capacity), I was seriously over-committed during that project and spent months afterward trying to get back into a groove (which never really happened). But... and here's a big but... I will soon have my name on an article in a peer-reviewed journal (Nuclear Instrument and Methods in Physics Research A) for the effort. I have been published in conference proceedings and have given presentations to some pretty amazing groups, which certainly gets some credit, but being published in a major journal is the full meal deal. Given my place in the grander scheme of things, this is a huge accomplishment for me, and hopefully presages wondrous things to come! A pre-press version of the paper was just released on arXiv.org if you want to take a look at how I spend my summer vacations these days (a PDF will open in a new tab):

Performance of a Full-Size Small-Strip Thin Gap Chamber Prototype for the ATLAS New Small Wheel Muon Upgrade

When it is formally published in NIM, I will definitely be having a major personal celebration!

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