illuminating science

So this week I’m reporting live (always wanted to say that!) from the AIP Congress in Canberra, Australia. AIP is the Australian Institute of Physics, and is the society that most physicists in Australia belong to (although, I have to confess, I’m not currently a member - when I get a larger income though! The Congress here is a chance for physicists from all around Australia to share their latest research, ideas and results, as well as to meet new people who might be doing relevant research. Finding new collaborators (i.e., people who want to work with you!) is a big part of this game! In total, 951 people have registered - that’s a lot of physicists in one place!

Aside from discussions over dinner and chats over coffee, there are two main ways that we communicate our research at conferences: by posters (large, A1-A0 sized displays that outline your research) or talks (20 minute presentations, usually with PowerPoint slides). This year, I had the opportunity to do a talk on my research (which is looking at the role of quantum mechanics in biology, how we can model it, and what physicists can learn from it!) There are many more posters than there are talks, and it gives you a lot more exposure, so getting a talk is a fairly big thing (at least for me! It’s the first one that I’ve done at a conference.) With all modesty, I pride myself on my talks and communication skills, so I think I gave a good talk - general enough that people not in my field could follow it, but with enough detail that experts would see we’re doing serious research. And especially compared to some of the other talks…physicists aren’t always the best communicators.

So, tonight is one of the poster sessions, where all the posters are displayed on boards and we wander around and read the ones we’re interested in. Usually, the author of each poster stands nearby to answer questions and meet people, so it’s a good opportunity to make new contacts (collaborators!) And my partner, Jenny (also a physicist!) is giving a poster on her work on melanin so I’m off to give moral support. The fact that they’re doing free catering and drinks doesn’t influence my enthusiasm in the slightest!

I went to a fascinating talk on Friday by Leggett, who received the 2003 Nobel Prize in physics, for his work on superfluids. (Notice that in physics, most people are referred to simply by their last names - “Smith did this, and Jones did that.” It helps to have a distnctive, but easily pronouncible last name!)

Leggett was speaking about macroscopic quantum mechanics - places where you can see quantum mechanics in “large” objects. Quantum mechanics is the theory which describes matter on the small scale where the everyday laws of physics break down. Motion of electrons, how atoms form and how photosynthesis harvest sunlight are all examples of where quantum mechanics knows exactly what’s going one. But why don’t we see any of these strange predictions in everyday life? Why can’t I be in two places at once, or tunnel through walls? The most famous example is Schroedinger’s cat, which we force to be, at least according to quantum mechanics, both alive and dead at the same time. Leggett asked us about this in the talk, and while most people were willing to believe that an electron could be in two places at once, most had a hard time buying that those same principles could apply to a full sized cat.

He then went on to discuss the possible implications of this. The first option is that quantum mechanics isn’t completely correct. Much in the same way that Newton’s laws of motion had to be corrected by Einstein’s theory of relativity when you’re talking about things moving very fast, maybe there is some new law of physics which comes into play with large objects. Roger Penrose has suggested that gravity might be the key. It’s the most troublesome force for a physicist, since it has such different properties to the other forces (like the electromagnetic force) - it’s much much weaker, but can span the whole universe. Perhaps for “large” objects, gravity somehow destroys quantum effects, and leaves us with the classical universe we see. Although no-one’s entirely convinced (except maybe Penrose?!), I’m certainly open to a possibility like that. Leggett then brought up a really interesting point which was whether this might challenge our typical view of physics, that by understanding the laws of small things, you can explain the big things. He speculated that the whole might be greater than the sum of the parts - that you can’t consider the little bits and combine them but instead have to consider the whole lot in one hit. I think what he was getting at here was more than the idea of emergent phenomena, which is where simple rules create complex behaviour (as seen in ants or superconductivity!) There, in principle you can explain the results from the basic rules, but it’s just easier to look at the whole system at once. What he was suggesting was that the basic rules couldn’t explain or predict the large scale behaviour - very interesting! I personally don’t like the idea, but that doesn’t mean it’s not true. I’m just more inclined however to believe that there is physics which exists on the small scale, but just isn’t important until you get to large objects - a bit like gravity!

The other possibility is that quantum physics is correct, but we just don’t know how to interpret it right. There’s the many-world hypothesis, about parallel universes, or there’s the usual “collapse hypothesis”, where “looking” at something destroys the quantum mechanics (which most people accept, but are uncomfortable with.) Perhaps, quantum mechanics is just maths - it doesn’t represent reality, there aren’t really wave functions, and all we’ve managed to do is come up with some clever maths which describes reality. I was surprised to hear that Leggett is tempted to believe this. Again, that really doesn’t appeal to me - quantum mechanics predicts so many things correctly that it’s hard to believe it doesn’t represent the real world. Of course, it’s possible that there’s more to the theory than we know (a bit like the discovery of special relativity) but I think that we’ve got to have at least an approximation of reality. Guess we’ll just have to see! The final section of the talk was about possible experiments which might be used to test these ideas, within the next 5-10 years, looking for large scale quantum effects in rings of superconducting materials, and in biological molecules (which is of great interest to me!). I couldn’t follow this bit so well, but it sounds like they’re doable, which would be very exciting.

So all in all, it was an impressive talk by a great speaker, who is not only brilliant but able to communicate his research well. In fact, I’m about to listen to another talk of his even as I type this - let’s hope it’s as good as the first!

After reading Kaku’s article on our universe, I found this neat little article on exotic matter, which mainly talks about what would happen if you had something with a negative mass. To really appreciate it, you probably need high school physics - knowing Newton’s law of gravity and conservation of momentum - but it’s a cool little discussion anyway. Negative matter (very different from antimatter!) almost certainly doesn’t exist, but it’s great fun to think about what would happen if it did. To me, that’s probably one of the most fun things in physics - considering something which should be impossible, such as travelling faster than light or time travel, for instance - and then thinking about what would happen because of it. In many ways, I guess it’s what good science fiction writers do, and of course no-one has done it better than Asimov, who came up with brilliant stories about the way that new discoveries in science would change not just technology but shape society too. Cool, hey?

Incidentally, does anyone know for certain the truth behind the story that “Isaac Asimov is the only author to have a book in every category of the Dewey Decimal system”? Many, many sites list it as true, but others say it’s only a legend, and that he’s only in 4 of the 10! I’d love a definitive answer…

Did you have a good weekend? Are you feeling that perhaps you’re not quite ready to get back to work or school today, or perhaps ever? Then you might want to consider Michio Kaku’s fabuous article about escaping our universe. It’s a really good read, talking about the state of our universe as we know it (including its age, 13.7billion years plus or minus a hundred million!) and our thoughts on dark matter and dark energy (did you know that it seems only 5% of our universe is ordinary matter?!)

He then goes on to talk about possible ways we might be able to avoid dying with the rest of the universe when the stars finally run out, and everything that’s interesting in the universe slowly comes to a halt. (Not to worry yet, though - that’s still billions of years into the future, and humans have only been around for a few thousand!) It’s a really good read, and opens up some thought provoking discussions about some of the exotic physics that’s come out in the last 10 years. He’s also written several popular science books, and though I’ve only read one of his it was very good - so I highly recommend him if you see one in the bookstore!

I might be a little quiet for the next couple of days - I’ve got a lot on! - but I’ll post again before the end of the week. Cheers!

So I’ve been a bit snowed under this week - I have a couple of papers in the pipeline that are well overdue, and I’m giving a talk at a conference next week. But I did want to finish my story about moving into my new place. So, after successfully navigating the housing game, it was time to move in our furniture. First snag - I have a queen sized bed, and the bedrooms are upstairs. Second snag - whoever designed this house wanted to make a place that was pretty, fasionable and pleasant. Nothing wrong with that, but they weren’t thinking about making it functional for moving furniture around. The staircase is narrow, and straight except for a sharp bend at the bottom which back onto the hallway. There’s a high-ish railing, with a fancy carved bit at the base of the stairs which is even higher, and the ceiling is sloped in what one presumes must be the latest fasion for architects. The upshot is that while I could bend my mattress around and up the stairs, it was nigh on impossible to fit the base part up.

We had two physicists and a very practical aunty with us, and we spent a good quarter of an hour trying desperately to work out a way that we could fit it through. Perhaps if we push it through a little this way, then rotate, er, or maybe not. It really was like one of those high school maths assignments, or one of those wooden puzzles that seems almost possible if you could just figure out the trick! In the end, we decided though that it was impossible to do it smoothly, and just went with the caveman approach - put it in the best position, and push. It worked, but only with grievous losses to both sides (of the hall, that is…)

But you could forget about getting a couple of heavy wardrobes up - they weren’t going to shift no matter what. We thought about using the upstairs windows, but some brilliant designer put awnings under them, so it would have been an absolute pain to try and lift them up, out and over. Instead, we’re going to go and buy some of those Ikea wardrobes that come in a hundred pieces, and can be simply assembled by inserting sprocket A into socket D using rings R1, P5 and S7 and washers A1-10, keeping the polarities inverted on every prime number piece. You can probably expect some complaints about that when the time comes…

So, my message to all designers out there, whether it be cars, houses, fasion, buildings, chairs, computers or ping-pong tables, before you release your masterpiece, your beautiful design, run it past a couple of physicists, a few average users, and a 5 year child. Chances are, they’ll be able to tell you why pretty doesn’t necessarily mean practical.

Well, I’ve spent the last couple of weekends (and then some…) moving house. And while I’d love to say that this was a relaxing process, there’s not much chance of that. First of all, I had to find a place - I’m renting, with my partner Jenny, and January is the busiest time of the year for rentals in Australia, so a property generally is only on the market for 24-48 hours if it’s half decent (i.e., they have an inspection, and are surprised if they don’t get two applications within a couple of hours!) So it’s a pretty cut throat business.

But I realised that I can use maths to get the best results: my situation was actually a perfect setup for the application of the “37% rule”. To recap: I’m trying to find the best place to live. But I don’t know how good the places on the market can be (taking into account size, location, price, facilities, etc), and if I don’t apply for a place immediately, I’ll probably miss it. So I have to see a property, and decide to either take it, or lose it forever and hold out for something better. Now, the more I pass up, the better sample I have of properties (and the better I’m able to say how “good” a place is) but I run the risk of missing the “perfect” home. Plus, I’m on a deadline (I had to move within 2 weeks, when my old lease expired.)

So what should I do? It turns out, to maximise my chance of getting the best place, I should sample 37%, or roughly one third, of the properties I expect to see. So, if I’m looking for 2 weeks, I might expect to find 20 “suitable” properties, satisfying my basic requirements of location and so forth. I should then look at seven of them with no intention of taking them, but noting which is the best. After that, I take the next property which is better than the best I’ve seen so far (from that first seven, or others I’ve seen since) - this gives me the highest chance of getting the best property. Of course, it’s entirely possible that the best property was one of the first seven, and I’ll have already passed it up - then I’ll be stuck with the 20th house, whatever it may be - but this scheme is the best compromise. Other variations exist which try to ensure that I won’t get the worst property, but have a lower chance of getting the best (by looking at fewer houses (say, 5) in that first sample), or where I’m willing to take any of the top three houses.

You’d be amazed, though, at how many situations this theory applies to. What if you’re walking down the restaurant strip, trying to find a place to eat? If you don’t want to go back, simply check out the first 37 percent of the restaurants, then keep walking till you find the next best one. Some people have also applied it to the dating game! Estimate how many people you’re likely to date in your life, dump the first 37% but keep a photo of your favourite on your bedside table. Then, marry the first one after that who beats your sweetheart! Of course, every rule has exceptions and sometimes you get an offer that’s too good to refuse, 37% or not. Sometimes, mathematics doesn’t have all the answers!

In the end, I didn’t exactly follow the 37% rule, but I did sample places and reject them, even though they were “adequate”, in the hope of finding somewhere better. Which at the end of the day, I suppose, is fairly common sense! I’ve got to get back to work for now (I’m giving a conference talk in a couple of weeks!) but I’ll relay the upshot of all this, and the trials of furniture moving soon. Cheers!

I was talking to a couple of people yesterday about a show they saw on TV which claimed that the Apollo moon landing was a hoax. The show’s claim was that NASA faked the whole thing in a movie studio in order to “beat” Russia to the moon.

I’d heard about this before (somewhere on par with people who still believe the Earth is flat) so I did a quick search on Google for rebuttals. High up there is the Bad Astronomy page, which seems to debunk every possible objection you could have. I’m can’t bare to go through all the ridiculous things these guys have come up with, but have a read yourself.

Now, my friends were intelligent and sensible people, but they were willing to believe that one of the most profound moments in scientific history was nothing more than special effects - and bad ones at that, if you listen to some of the sceptic’s claims. It goes to show, again, how easy it is to present an unbalanced, one-sided view of something, and yet make it so believable. And of course, it sensational and controversial stuff like this that makes for ratings - people love a good conspiracy theory (and I have to admit, I still suspect my mum had some involvement with that whole Tooth Fairy business)

And now, I’ve got to go and print out all these webpages to give to my friends to read…

Hope everyone had a good Christmas! Now, time to get back to it! First up, researchers from Toronto have developed nanocrystals which are able to absorb infrared light. This is basically heat, with a longer wavelength than visible light. While we can’t see it with our eyes, we can feel its effects on our skin, for instance. (Note that it’s not what burns us - that’s ultraviolet (UV) light. Again it’s invisible to our eyes, but has a much shorter wavelength which means much more energy and is what burns us.)

You’ve got to wonder - whare are these so-called “smart clothes”, which can generate power, resist stains and adjust their temperature, going to do to fashion?!