Published online 22 March 2005 | Nature | doi:10.1038/news050321-7

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US physics meeting

Members of the American Physical Society are gathering from around the globe for one of the world's biggest annual physics meetings. As 2005 is the Year of Physics, celebrating the centenary of Einstein's most famous papers, this get-together promises to be a special one. Sarah Tomlin reports from Los Angeles.

<blogentry><entrydate month='03' time='17:30' daynum='04' day='23' year='2005'/> Day 4: Straw poll

I've been conducting a very unscientific poll all week regarding physicists and the World Year of Physics. Here are some inconclusive results. A Japanese physicist from Okayama told me that his hometown had many public events planned for the WYOP. But a student from nearby UC Berkeley confessed that he had not heard of the celebrations until this meeting, and only then because his advisor encouraged him to participate. Someone else I stopped to ask about Einstein turned out to be a chemist - attending his very first APS meeting. He claimed to be highly interested in all things physics, including Einstein, but acknowledged that not many of his colleagues would feel the same. Last month at the ACS meeting he overheard a conversation by two chemists who seemingly knew nothing about the anniversary year.

A researcher from Phillips agreed that the nonscientific public in the Netherlands was generally unaware of the Einstein celebrations and argued that it would be better to focus on one day than to try and maintain enthusiasm for a whole year.One thing I have learned this week is that it is best not to follow too closely in the old man's footsteps. The biennial Einstein prize in gravitational physics that the APS inaugurated in 2003 was this year awarded to the late Bryce Dewitt, who helped pioneer the quantum theory of gravity. Dewitt sadly died last September at the age of 81, and will be awarded the prize posthumously at the APS April meeting in Tampa. This is not, alas, the first time an Einstein prize recipient has died before being granted the honour. In 2003, the first Einstein prize was awarded jointly to Peter Bergmann and John Wheeler, but only Wheeler was able to attend the meeting in Philadelphia to receive his prize. Bergmann, who had worked with Einstein as a young man in Princeton, passed away in October 2002. Their theories, at least, live on.

</blogentry><blogentry><entrydate month='03' time='23:25' daynum='03' day='22' year='2005'/> Day 3: Lunch-box experiments

Marvin Cohen, the president of the APS and UCB physics professor, is a keen proponent of outreach, especially during the WYOP.

Over lunch it’s good to watch him put his food to the good purpose of illustrating science. With a plastic knife and fork and three green peas he whips up a demonstration of the work of his friend and colleague Alex Zettl, also at Berkeley. Imagine the knife is made from carbon nanotubes, says Cohen. And the peas, he says, balancing them on the knife, are droplets of molten indium. When you apply an electric field along the nanotube the droplets move closer together, he says, as the peas roll towards each other along the knife. Thanks to the surface tension in the droplets, the bunched up peas can even merge together and should be able to prop up another row of nanotubes, in this case a fork. This process would be able to drive a tiny nanomotor, say the authors (Regan et al. 2005 Appl. Phys. Lett. 86 123119). Just imagine, says Cohen excitedly, the fork wobbling on the peas. Cool stuff. I can’t help but imagine what wonders could be revealed if Cohen had the whole buffet to play with.

</blogentry><blogentry><entrydate month='03' time='22:00' daynum='03' day='22' year='2005'/> Day 3: How not to make a splash

Here’s a neat trick. Sidney Nagel, from the University of Chicago, and his graduate student Lei Xu, have discovered something fascinating just by filming splashing droplets.

This is classical physics: the sort that does not depend in any way on Einstein’s 1905 discoveries. They simply watched a droplet hit a flat surface and observed the shape the splash made. They then lowered the air pressure - down to one-fifth atmospheric pressure - and repeated the experiment. This time the droplet made no splash but simply rolled away smoothly from the point of impact. You can see a movie of their results here http://kauzmann.uchcago.edu.

No-one would have expected that air - stuff we take for granted all the time - plays such an important role in splashing. Nagel and Xu are finding other surprising results: highly viscous drops are more (not less) likely to make a big splash. There are potential industrial implications of this work for ink-jet printing and fuel combustion. But Nagel wonders if NASA would be interested. Does this mean there would be no splashing on the moon?

Today is World Water Day, and the skies above LA (ever the city of excess) are dumping record-breaking amounts of rain on the city. As I watch the water droplets splash and roll down the windows of the shuttle bus I ride back to my hotel I think of Nagel’s work and wonder what would happen if you sucked the air out of LA. Would no-one be able to make a splash? Please don’t tell Hollywood…

</blogentry><blogentry><entrydate month='03' time='11:00' daynum='02' day='21' year='2005'/> Day 2: First impressions aren't everything

Most telling quote over dinner last night: "Is your tie a fractal?" Given such conversational tidbits, you would expect nine scientists to be able to figure out the bill to the nearest decimal point. Disappointingly they rounded the total; but at least it was in the waiter's favour.

One way to spot a physicist in downtown LA: the stylish pocket protector. I kid you not. The "World Year of Physics" stand here is giving away souvenir plastic pouches that can hold multiple ballpoint pens while protecting your jacket pocket from unfortunate ink stains. And I thought LA fashion week was over last weekend!

</blogentry><blogentry><entrydate month='03' time='19:50' daynum='02' day='21' year='2005'/> Day 2: Physics isn't always black and white

What would Einstein have to say about racism in America? Quite a lot, according to Sylvester James Gates Jr., a physicist at the University of Maryland. Gates, who is black, met Einstein while a high-school student at a segregated school in Orlando, Florida. This special visit was organized by a superb teacher who was serious about teaching special relativity to his students, and Gates instantly became inspired to study physics. Years later Gates discovered that Einstein had struggled with the racism he found in America; he told the conference that Einstein once said: "The more I feel American, the more this situation pains me." Gates related how Einstein felt compelled to act, as he did on other social issues, once reportedly describing racism as "America's worst disease" and campaigning against the post-World-War-II lynchings of black Americans. On another occasion Einstein apparently invited a visiting African-American singer to stay in his home, after he was refused a hotel room in Princeton. Gates wonders if Einstein's own experiences as a minority influenced his attitudes towards others, but he also suspects that Einstein had a moral intellect equal to his scientific one.

</blogentry><blogentry><entrydate month='03' time='22:50' daynum='01' day='20' year='2005'/> Day 1: Party like it's 1905

Physicists are enjoying their moment in the sun. Thousands of them, like me, stepped blinking out of the LA airport into the bright light of spring. They are here for a week of serious physics, but I hope they packed their party hats because we're also here to celebrate everyone's favourite physicist: Albert Einstein.

The World Year of Physics (WYOP) is a year-long celebration, endorsed by the UN and timed to coincide with the 100th anniversary of Einstein's annus mirabilis. In 1905, a 26-year-old Einstein published three era-defining papers in quantum mechanics, Brownian motion and special relativity. By feting one of the icons of the twentieth century, many physicists, worried about declining student numbers, hope that the events planned for 2005 will revitalize interest in their subject.

It is almost impossible to define a single moment that captures this year-long 'experience', and this LA meeting is just one of many international events hosted by some 30 nations contributing to the WYOP. But I'm still keen to find out what physicists here think the year of physics is all about. What is it supposed to achieve? And how is it going so far?

I heard one rumour that Wal-Mart turned down a request by US physicists who wanted to send travelling physics 'road shows' to its stores. Just imagine Newton's third law up against the law of the lowest prices. But perhaps you don't need the world's largest retailer to sell your ideas. The Einstein@home project reported a successful start to its distributed computing campaign last week. Anyone, even Wal-Mart customers, with spare computing power and internet access can download software designed to look for gravitational waves. These waves were first predicted by Einstein and physicists are hoping to find evidence for them in the vast datasets collected by detectors in the United States and Germany. Similar to SETI@home, which searches for extraterrestrial signals, the more users there are the more chance there is of finding something interesting. By last Monday, the 126th anniversary of Albert Einstein's birth, Einstein@home reported more than 55,000 participants from 115 countries. They now claim to be adding roughly a thousand users a day, which gives them the rest of the year to reach their target of hundreds of thousands of part-time gravitational physicists.

If one goal of the WYOP is to get more of the 6 billion people on this planet interested in Einstein's ideas then we are off to a decent start.

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