illuminating science

Tonight the most coveted, the most prestigious and the most hilarious awards are going to be announced - that’s right, the Ig Nobel Prizes! From the website, “The Igs are intended to celebrate the unusual, honor the imaginative — and spur people’s interest in science, medicine, and technology.” Have a look at the past winners - truly science at its best and weirdest!

I wish that I could be at the ceremony, since I’m already in the UK! But alas, as given in my last post, I’m away for the weekend and am unfortunately going to miss it. Maybe next year! But definitely check out the website tomorrow to see who won!

I’m going away for the weekend to explore lovely Lisbon, Portugal, so no posts for a couple of days. Have a good weekend! And don’t forget, if all goes to plan, the prize winning attempt flight for the X-Prize will be happening on Monday (pick a timezone, any timezone…) - if you didn’t see the webcast last time, I’d definitely recommend it this time!

SpaceShipOne has touched down, after a successful flight (Google news). It took about an hour for the plane to carry the ship to its starting height, and then only minutes for it to reach space. There was some odd rolling on the way up, and I think they terminated the burn early, but SpaceShgipOne made it to space and beyond. For the first time, there was a camera mounted inside the ship, and the views of Earth were amazing.

We’re still waiting for confirmation form the judges that this was a successful attempt, but assuming so, the two week count for their second attempt and the $10 million prize money has started. Hopefully the odd behaviour on the way up won’t delay the proposed relaunch next week. It was fantastic to watch this live!

Oh, and a question of scruples for you all: The X-Prize requires a ship with one pilot and two passengers, but the passengers on this flight were replaced by ballast (as allowed by the rules.) If you’d been offered one of those passenger seats for today’s flight, would you have taken it? I have to say that I would have, despite the obvious risks with what the commentators called “test flight in its purest form.” In a room of three physicists, we had two votes for yes and one for no - what would you do?

The first X-Prize flight is going to be happening in the next hour or so - you can watch the webcam through NASA - Webcast of SpaceShipOne X-Prize Attempt. It’s already live, with various stirring speaches, etc. Love to write more - but I’ve got to watch this! I’ll post as soon as I hear the outcome of the flight!

Update: The pilots (of the plane that will carry the spaceship to an inital height) and the astronaut Mike Melvill (the world’s first private astronaut, after piloting the maiden flight on SpaceShipOne in July) are on board. If the winds die down, expect take off in half an hour.

Update: It’s now 5 minutes to launch. Winds have died down, WhiteKnight, the carrier plane, have started their engines. Very exciting!

Thought leeches were out of fashion in medicine? Well, they’re still around - and so are maggots.

While not everyone is enthused by the idea, clean and carefully bred maggots are being used to eat dead tissue from slow-healing wounds. Basically, you put small maggots into the wound, bandage it up, and remove the now-plump maggots a day or two later. They’ve eaten the dead tissue, while leaving the rest of the wound untouched.

If this sounds a little, er, unpleasant, then listen to what Donna Nordquist, a recent patient, had to say in the Wired article:

When it comes to the “ick factor,” the 63-year-old Nordquist is definitely a trooper. “If you know the difference between them being on a wound and coming out of a garbage can, it makes it a lot easier,” she said. And while she felt the maggots in her leg, she didn’t mind. “I knew they would wiggle and squiggle and move around. Let me tell you, you can go through a hell of a lot of pain if you can keep your leg.”

And she figures other patients will accept maggots, too. “They just haven’t hurt long enough. When they have, they’ll jump at it.”

Yet again, nature seems to have the solution to some of our problems. Neat, hey?

A neat article on Nature about physicists helping to make the perfect piece of popped popcorn (which Peter Piper picked. No, wait…)

Popcorn is made by heating corn kernels until the pressure inside them builds up enough that it pops the hard outer shell and forces the starchy interior to explode outwards. “Good” popcorn, aside from being served with lots of salt, has big, light, fluffy pieces. This means we want the explosion of the popcorn to be as powerful as possible - we want the pressure inside to very high when the kernel explodes! But this is hard to do, as you can’t do much to the corn except heat it. So, physicists at Stanford Medical School in California realised that if they could lower the pressure outside the kernel then the pressure difference between the inside and outside would be bigger - and the kernel would explode with even more force and hence be bigger. (It’s interesting to think about the “limiting case” where you pop kernels in a vacuum. When the kernel pops, will it just keep expanding forever? After all, there’s no air to slow it down or stop it, right? The catch is that as it expands, it will cool down, and eventually the steam turns back into water and the starch “sets” into a normal kernel. We don’t have to worry about this for corn in a saucepan however, because everything happens so quickly that heat loss isn’t important - that’s why corn comes out hot. We call this type of process adiabatic, meaning no heat is lost to (or gained from) the environment.)

But this isn’t just theory! To try it out, they simply attached a vacuum pump to their pressure cooker - this reduces the amount of air inside, and hence the pressure. The resulting kernels were about twice the size of normal ones, and for minimal effort. All of this means that next time you go to the movies, they can offer you a SuperMegaGIANT sized popcorn container that has only half as much popcorn as a regular Small size!

If you want some more details, have a read of their paper online at the arXiv. Just follow the PDF link. There is maths, but there’s a lot of text as well to make it quite readable.

At the risk of becoming monotonous, yet another competition for private space flight has been announced. This time, it’s for a craft capable of carrying seven astronauts (as opposed to two for the X-Prize) and is worth $50 million (instead of a measly $10 million.) While it won’t have the same publicity, particularly with NASA planning to fund still more prizes of its own, this will all contribute to keeping the momentum going for private space travel to become a reality. Slashdot provided the tip-off.

Also, while we’re on the topic, the main rival of SpaceShipOne for the X-Prize, called the da Vinci Project, has pulled out of its planned launch next week. That means SpaceShipOne (who just won the big contract with Virgin) are the heads of the game.

Hot on the heels of my post this morning, ABC News is reporting that Richard Branson, overlord of Virgin airlines (and music, mobiles, etc), has signed a deal with the US company behind SpaceShipOne, the front runner for the X-Prize and the first privately owned ship to travel to space. He wants to send “thousands” of fee-paying astronauts into orbit within the next five years.

The company, dramatically called “Virign Galactic”, plans to launch its maiden flight in three years, making space travel possible “for ordinary people”. Of course, “ordinary” means being able to fork out $291,000 per flight (about £115,000 in GPB) per flight, or about the cost of a modest house. Again, technical problems abound, but the new era of space travel may well be here!

(For the trivia minded, “space” is defined as 100km above Earth, roughly where the atmosphere is too little to worry about it, but it’s basically arbitrary. And don’t forget “astronaut” basically means anyone who’s gone into space - for Virgin Galactic, you need only 3 days training!)

Now this has got be what science is all about. Take a 25m swimming pool. Fill it with syrup. Then see if you swim faster or slower in syrup than in water.

You might instictively think, “Well, of course you would go slower in syrup - it’s too thick!” But, being thicker, each stroke of your arm would propel you forwards further. So the answer? You go at roughly the same speed! When you increase the viscosity (”thickness”) of your liquid, the extra drag on your body is cancelled by the extra pull of your arms, and you can swim along at the same speed.

Of course, this isn’t completely true. The syrup was only twice as thick as water, and if it gets too thick then viscous forces dominate. (A nice thought experiment is to imagine that if the viscosity of the fluid didn’t matter, we could swim at the same speed in a bowl of jelly (=jello, for the Americans) right up until it set, when we would suddenly stop!)

And this really is a serious question - think of people trying to understand aerodynamics, particularly for different planets where the air has different densities. Or what about bacteria swimming through the human body (a lovely thought…)?

Just spare a thought for the poor guy who had to clean out the pool afterwards…

This has got to be one of my all time favourite comics. And if you’ve ever taken a course in physics, you might have thought your lecturer was being just like Calvin’s Dad…

I love it!

AMSAT, an amateur radio mission to Mars in 2009. They’re going to send a satellite to Mars at a cost of 10 million euro, to prove that a private company can also send missions to space. Of course, they already have a track record, having being involved with nine previous space missions.

Along with the Ansari X-Prize (which offers US$10 million to the first successful private space craft) things are really heating up for the private space industry. Space ownership is currently an interesting, but largely hypothetical question. But if people can jet off to the moon or their favourite asteroid for no more than a few hundred thousand dollars (cheap if you’re a decent sized company!!!) then we’re going to really have to start thinking about the implications. Will people need to file a flight plan with the U.N.? As unlikely as life on asteroids or in space seems, could quarantine become an issue? What sort of regulation do we need - does someone need to check every space craft for safety, just like our airplanes? We’ve seen that even NASA has their work cut out for them making space travel safe. An interesting time ahead for space travel indeed!

Thanks to Slashdot for the heads up, and to Google for the remarkably good automatic translation of the article.

I have to admit, I’m a big fan of the show Stargate, and I’m going to use my position of power to plug it :). The story goes that an ancient race (called, with great originality, the “Ancients”) built a set of devices (the Stargate) capable of (almost) instantaneously teleporting people across the galaxy. Our explorers from Earth discover the Stargate and begin to explore the universe, where they encounter humans taken from Earth thousands of years ago and various aliens, good and bad. It sounds kind of hokey, but it really is a cleverly designed show, based on the really-not-so-good movie.

Several things about it really appeal to me - firstly, the scripts and acting are (generally :)) fantastic - the writers really put a lot of effort into the show. Most notably, a lot of work has gone into making the show self-consistent, and constantly referring back to previous episodes. Sometimes that’s a direct sequel, other times just an oblique reference, and sometimes it’s a piece of technology they’ve brought back from an alien world which they’ve learned to use. It makes for a wonderfully rich universe! But, best of all, a real effort is made to conisder true physics, and to try and make the show as consistent with it as possible. Of course, using wormholes to travel around the galaxy is almost certainly impossible, but if you accept that it’s true in the Stargate universe, then a lot of their other physics follows logically. They explore general relativity, time dilation, quantum mechanics and cloning with quite a lot of thought, and even though it’s sci-fi, it’s usually believable enough for me to enjoy it!

Plus there’s lots of neat physics references. My favourite is this: our hero Jack (aka McGuyver) is trying to do a physics crossword and phones up Daniel for help:

Jack: I need a seven letter word. Up, Down, Charm . . .
Daniel: ‘Strange’.
Jack: Yeah. Well, thanks anyway.
Daniel: The word you’re looking for . . . (Jack cuts him off)

What they’re talking about is different types of quarks, subatomic particles that combine to make protons and neutrons. They come in six types, which are Up, Down, Top, Bottom, Charm and Strange. The names don’t mean anything - they’re just names! (Each type incidentally comes in three flavours - Red, Green and Blue, but these have nothing to do with real colours - they’re just names, and in fact quarks are much smaller than any light wave!) I just liked that there was no further explanation of the physics - a nod to those in the know

Expect some more Stargate (and more sci-fi!) physics posts to come!

This is slightly old, but New Scientist are describing a chip developed by Intel which uses heat to generate random numbers for a prize draw in the UK. The chip, known as ERNIE 4, can generate a million truly random numbers an hour. Why do we say “truly random”? It’s because normal computer generated random numbers are generated using a mathematical formula. If you knew the formula, and knew the last random number, you could generate the next number in the sequence. True random numbers mean you can never predict or calculate what comes next - vitally important for cryptography, and even for very sensitive modelling, etc.

Of course, this isn’t as cool as using lava lamps or webcams (a good read!) to generate your random numbers, but all rely on the same principle - random fluctuations. Heat fluctuations in a chip, random noise in a video sensor or the hypnotising flows of oil in your lava lamp - all these schemes take something natural and large scale and process it to turn it into usable, digital, random numbers. (Interestingly, the webcam scheme is free - opensource, in fact! This makes good random numbers accessible to everyone, where previously it was very expensive. Good on ‘em!)

Some quotes out of the New Scientist article that I like: The chip has “been designed to be tamper resistant and immune to the threats of hackers.” As opposed to what, exactly? Do you typically design chips to be easily hacked into? And, supporting that statement, “It is not connected to the outside world except by a plug”. We’ll give them the benefit of the doubt and assume they mean a powerplug rather than a phoneline! Of course, there’s nothing to stop the lottery organisers from hacking into it in person…

Dogs have just graduated from the airport baggage checks - next time you have a check up, it might be a dog that’s doing the checking. Dogs are able to detect cancer by smelling urine from the patients. Chemicals caused by bladder cancer can be detected by the dogs even in minute quantitites. In a trial study, the dogs had a success rate of 41 per cent - compared to only 14 per cent by chance alone. A question though: What fraction of the mistakes were false positives or false negatives? A false negative would be a “Type I” error in statistics, the worse possible result, because a sick person doesn’t receive treatment. A “Type II” error, i.e., a false positive is less of a problem - further tests will reveal that they are in fact healthy, and aside from a few days of stress, no harm is done. For a reliable test, we have to have very few false negatives.

Interestingly, the dogs consistently identified a healthy control sample as being cancerous in the training phase - further tests revealed the volunteer did indeed have cancer! They’re now going to see whether dogs can detect other types of cancer as well (e.g., anecdotal evidence describes dogs constantly sniffing moles that turn out to be cancerous.)

Right here at UQ, researchers from Physics have developed XeroCoat, a cheap, easily produced anti-reflective coating. Their main aim is to apply it to solar cells - by reducing the amount of light reflected from the surface of the cell, more will reach the processing part. This means higher efficiency, and they’re predicting increases of up to 8% (which is a lot for solar cells!) Using an anti-reflective coating isn’t new, but is normally too expensive to use for general purpose cells. XeroCoat, however, is cheap to produce and easy to apply (no high pressures or temperatures needed!) so can be used for cheaper cells.

XeroCoat also has applications beyond solar cells - it also stops surface from fogging up. Think about glasses, goggles, windscreens, (camera LCDs?), even bathroom mirrors - the list goes on! Of course, it’s not full developed yet, but with applications anywhere where you don’t want reflections or fog messing up your image, it looks like a winner.

A bit slow in the world of science yesterday, so nothing of great interest to report. One welcome bit of news today is that NASA has announced that the Mars rovers have had their missions extended for another six months.

These are the robots Spirit and Opportunity which are doing detailed studies of Mars’ soil and rock formations, with a particular interest in past water activity on the Red Planet (and they have found much interesting evidence!) Originally slated for 90 day missions, Spirit is now at 263 days and counting, with Opportunity just three weeks behind. I think this is great news for the space industry after some bad publicitly recently, such as the loss of the solar capsule and the ill-fated Beagle 2 probe. Chalk up at least one resounding success for NASA!

From Michael Nielsen, David Deutsch, who is one of the founders of quantum computing, now has a weblog. No hardcore physics - just interesting comments and thoughts about physics and the world around us.

Uncertain Principles has a really interesting post at the moment about singularities in our evolution. The basic idea is that given the rate that we’re producing new technology and science, “…there will come a point in the near future when changes occur so rapidly that humans (or our post-human descendents) will become essentially unrecognizable.”

He very appropriately points out that while this is fascinating for science fiction writers, it doesn’t necessarily hold up in real life - pop on over to find out why. A great read!

Interesting story from ABC News about a group from Australian National University who may have developed a vaccine that prevents removed cancers from resurfacing. So far, it has been successful in preventing melanoma (skin cancer) in mice, and they are looking to begin human trials next year.

The idea of a vaccine has been bandied around for quite a while, and it’s important to note that this isn’t like vaccinating for measles - it won’t prevent you from getting cancer. But if you do get it, and it can be removed, then this vaccine, in theory, greatly improves your chances of it staying gone. Not the holy grail of cancer research, but still potentially an important discovery.

There’s a lot of interest amongst physicists at the moment in using biology as a source of intesting physics and useful tools. (In particular, this is the subject of my PhD project!) A big part of this is that biology has had millions of years of evolution to fine tune itself, and so can often perform incredibly complicated functions with very simple “machinery”. We might be able to learn or copy from these techniques to build better electronics, nanomachines, etc.

Recently, researchers have successfully taken the molecules responsible for photosynthesis in plants and used them to make solid state solar cells. (Solid state means that it’s all built onto a chip, and there’s no liquid, etc - an important distinction.) The photosynthesis molecules, called “Photosystem I” or just PSI, were collected from spinach. They’re incredibly small but collect and process light with very high efficiency. So far, the group has achieved only very small currents from the cell and there are still many issues to be addressed, but they’re hoping that ultimately these cells will do much better than the current silicon-based solar cells.

Another possibility is “artificial photosynthesis“, where solar cells are built using the principles of photosynthesis but without using the actual biological units. Our Soft Condensed Matter group at UQ is investigating this, as well as exploring whether the skin pigment melanin melanin might be another possible material for solar cells.

Biophysics is an incredibly exciting area, drawing on the knowledge of two very diverse fields - if you’re torn between biology and physics, fret no longer - you can do both!