Wednesday, March 31, 2010

Don't Forget...

...to add your comments and headlines to our April Fools Day contest! You can submit your ideas here or on our Facebook page!

Do I need a better reason to post a picture of puppies?
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Smashing!

"Smashing" is a European exclamation that I wish had caught on in the states. It just seems to have a certain ring to it...but maybe that's because it reminds me of physics.

I can't think of a better word to express my excitement and joy for the big announcement this week from CERN. The LHC swung those little protons around that 26 kilometer track aaaannnnndddd....SMASHING! Yes, the LHC is officially colliding particles at (another) record breaking (but a little more breath taking) energy of 7 TeV!!!

I would give you a round up of stories on this subject, but the Knight Science Journalism Tracker has done far better a job, so I'll just point you there. KSJT also pointed out how interesting the collision images are looking. Instead of boring spikes on nameless graphs, we are getting some really lovely and illustrative images from the experiments located on the LHC - ATLAS, ALICE, CMS and LHCb.

The LHC already holds the world record for highest energy collisions - in November 2009 it went just a hair above the Tevatron's 1 TeV energy and reach a still stunning 1.18 TeV.

Cosmic rays strike our atmosphere at even higher energies than those created in the LHC - a point made by physicists dispelling ideas that these collisions could create black holes that might eat the Earth. And those are very energetic collisions - relatively.

1 TeV (1x10^12) is not a great amount of energy to us. It's about the amount of energy possessed by a slow moving ant. If you nearly double that energy, up to about 3x10^20 eV, you would have about the amount of energy possessed by a bowling ball if you held it at your waist and dropped it.

These big accelerators are so amazing, and cost so much money, because they put all that energy into individual particles. There are roughly 3x10^28 protons in your body. Even if only one very slow ant is nothing to worry about, if you could get that many of them together, you'd have some fightin' power.

But the point is not to put together a lean, mean fighting machine. It's to take things apart. And to do that you need high energy, at least on a relative scale.

The cathode ray tube in your TV is one of the simplest examples of a particle accelerator (assuming you don't have a flat screen yet). It shoots electrons at your screen, creating colorful images, at about 30,000 eV (30 keV).

Around 1943 the idea of a synchrotron, a circular accelerator that would drive particles using magnets, was proposed. In 1952, the Cosmotron at Brookhaven Lab in Long Island began operations at 3 giga-electron volts (3 GeV or 3x10^9 eV). A handful of other synchrotrons followed, including the 12.5 GeV Zero Gradient Synchrotron (ZGS) which started its operation at the Argonne National Laboratory near Chicago in the early 1960's. Then in the mid 1960's, the SLAC linear accelerator opened in Menlo Park, California, and now accelerates particles up to 50 GeV.

During the 1960's, physicists were seeing new machines begin operations at tens of GeV, but the dreamers had their sights set much, much higher. Plans were being put into action to build a synchrotron that would operate at 1,000 GeV, or 1 tera-electron volt (1 TeV). The accelerator, located at Fermilab, was eventually named the Tevatron, because of this 1 TeV goal.

Reaching 1 TeV was a tremendously long and expensive project and rather than follow the course of the early synchrotrons, which increased their energies by increments of one, two or three GeV, the LHC is now operating at seven times the energy of the next most energetic experiment.
While energy is not the only objective when building accelerators, it is notable what a tremendous leap the LHC will make for high energy physics. We've been pushing on the ceiling of 1 TeV for some time, and the LHC is just blowing the roof off the place, advancing all the way up to 7 times that energy.

But this leap in energy also means there will only be one such machine of this size in the world, and it means there aren't any trial runs. There isn't a 3 TeV machine that LHC scientists can look at to avoid mistakes. It's now or never, and it is truly incredible that everything has gone as well as it has (yes, it has gone well if you consider how wrong it could have gone).

So I say, smashing! Brilliant! Huzzah! This is truly a thrilling thing to see unfold, and I feel fortunate that I am alive to see it happen.

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Tuesday, March 30, 2010

Call for April Fool's Day Headlines!

April Fools day is rapidly approaching, and we here at Physics Buzz always look forward to the opportunity to make up our own reality; i.e. write fake physics news headlines. And never fear - this year will feature our regular roll of spoofs.

[Photo: Steven Chu]

But this year we thought we'd open the flood gates and give YOU, our dear readers, the chance to participate!

Send us a funny/clever/interesting/foolish physics headline and/or photo caption to feature on Physics Buzz on April Fools day. You can come up with your own headline and short (SHORT) story from scratch, or create a caption for one of the photos we've posted here or at the Physics Central facebook page in the album Headline Pictures.

[Photo: Edison]:

Post your headlines and comments in the comments section of the blog, or on the Physics Central facebook main page.

You'll be able to see everyone's headlines in the comments, and on Thursday we'll post our favorites!

We've trained you the best we could, readers. Now go, and fulfill your destinies!

[Photo: the lab]:
[Image courtesy of Urcomunicacion]

[Photo: the machine]:
More photos on Facebook! Go to the PhysicsCentral profile and view the photo album: Headline Pictures.
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Monday, March 29, 2010

OK Go Loves Potential Energy!!

There is nothing I can say to prepare you for the awesomeness of this video (which you very well may have seen already, because it has been EVERYWHERE and you are a very cool person who knows what's going on in the world):



The power of potential energy!

There is one particularly giggle-inducing moment when a gently rolling soccer ball releases an upright piano from its position 5 feet above the ground with a grand CRASH! It's a bit poetic how such a small thing can create such a large effect. Even though there are a few places where electronic devices are used, the entire machine keeps running without human intervention - without the addition of energy. It's continual motion relies on energy stored prior to the domino tip-off. Once again, with only a few exceptions, all of this energy is mechanical, not electrical. I think in this day and age we are used to relying on electricity as our primary energy source, and seeing mechanical energy put to work in such a creative way is a real treat. And once again, do not underestimate the awesome power of entertainment when trying to educate.

Energy is sometimes a tough thing to think about because it is not a physical thing you can hold in your hand; but it does exist in physical things. For example, I can take physical energy out of my muscles and put it into a bowling ball when I lift that ball above the ground. When I drop the bowling ball, the bowling ball passes the energy into the floor. I can't hold onto energy, but I can hold onto objects with energy. I can feel energy if I put my hand under that bowling ball as it falls. And if I secure the bowling ball in a sling above the floor, I can leave that potential energy there indefinitely, and release it with only the amount of energy it takes to release that sling. This goes for everything from marbles to pianos. When an object has the potential to release a lot of energy (like a piano dangling 5 feet above the ground) we call that potential energy. As the piano falls, the energy it is releasing is now called kinetic energy.

Systems want to be in the least energy state, which is why water always runs to the lowest point in a house and why the piano falls. In classical systems, gravity is often the dominating force that determines where the lowest energy state is. I will mention briefly how this relates to avalanches, which are another example of very small forces triggering massive results.

For the same reason a small soccer ball can destroy a piano, one skier can trigger a massive avalanche (see our other posts on Physics Buzz here and here). The snow on the side of a mountain has potential energy because it is lifted high above the valley floor. Rather than a rope or sling holding it up, the snow is held in place by frictional forces - the falling snow tends to stick together and stick to the mountain. But as the layers of snow grow, the weight of the snow drifts may over power those frictional forces, and an avalanche may occur naturally. Sometimes the weight of the snow drifts is almost, but not quite enough, to overcome those frictional forces. The snow drifts are like the piano held up by the rope. It only takes enough energy to undo the rope to send the piano crashing to the ground - but nature does not approximate. If the snow drift has almost, but not quite enough energy to overcome the frictional forces, it will remain still. The snow will stay on the mountain side.

But a soccer ball might happen along and trip the chord holding the piano, or a skier might go by and push on the snow drift. That little bit of energy might be enough to overcome the initial momentum and send the snow hurtling down the mountain. Initial momentum is the momentum it takes to get a system moving, which is a little more than it takes to keep the system moving. So if your car stalls, it takes one big push to get it rolling, but less energy to keep it rolling. Sometimes a system hangs delicately on the edge of having just enough energy to reach the necessary initial momentum, a very small outside force is enough to push it over the edge. And we can thank those classical laws for the Rube Goldberg machines we love so much.

Wired has a great story on the construction of the machine by Syyn Labs, a Los Angeles-based arts and technology collective. The article includes four "making of" videos which just might motivate you to get out your old Mouse Trap board game, or build your own, like this one from the Myth Busters (it's a holiday Rube Goldberg machine, which is out of season, but adds a bit of cheer to my rainy afternoon).





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Friday, March 26, 2010

March Meeting Round Up

For those of you who couldn't join us in Portland, you missed some great physics and some fantastic smells. Even downtown Portland smells like pine trees and fresh rain all the time. For me, living there would be akin to Homer Simpson's land of chocolate fantasy.

Well, maybe not quite. I might like to live the land of chocolate as well.

ANYWAY - There was a lot of amazing reporting that came out of the meeting, and I wanted to share some of the great story highlights with you. A few of honorable mention:

Geoff Brumfiel at Nature did a great job sketching out the feeling of the meeting outside the session rooms. And often, that's where the real action is. This link will take you to the first of about a half a dozen posts.

Great stories by Laura Sanders at Science News on Superchilly Chemistry, and the ways that body heat can change the airflow in your office.

"How does a worm wriggle," asks Adrian Cho at Science News. Cho also covered what seemed to be the big breaking news of the meeting. Here's the headline he gave it: "Quivering Gizmo Ushers in Quantum Machines."

Scientific American's Davide Castelvecchi covered that same story but titled it, "Macro-Weirdness: Quantum Microphone puts Naked Eye Object in 2 Places at Once."

Finally, New Scientist reporter Richard Webb also covered that story, which he dubbed "First quantum effects seen in a visible object."

This might be my favorite story from the meeting. First, it introduces a neat instance where packets of vibrational energy - phonons - are detected. Like photons, which are individual packets of light, phonons can't be split up into smaller pieces. The researchers used the phonon detecting device to show that they could measure a (barely) visible mechanical resonator both resonating and not resonating at the same time. Macroscopic objects in two states at once!

Webb also covered some interesting efforts to understand dark matter by studying matter we find here on Earth.

And despite what Chad Orzel says, he is a perfectly decent pool player. His team did lose two out of three, but that was partly due to a rogue 8-ball that I suspect may have had control of its own motion. Orzel's recap of the meeting also quite enlightening, entertaining and just a wee bit personal (don't eat the chicken fingers at fries at the Portland convention center, I guess).

Leading up to the meeting I promoted James Kakalios' public lecture on the Physics of Superheroes, and he delivered an amazing performance. I think at this point he's nailed down his routine pretty well, and it is a genuinely awesome routine to see.

What I loved most about his talk, was actually Kakalios' insights into the ways that people get interested in science, based on his experience with this whole comic book thing.

Kakalios has gone from physics researcher and comic book nerd, to nationally recognized science and entertainment expert in a relatively short amount of time, and without ever really having any intention of reaching this many people. While many people try very hard to get the public excited about science, and to convince them of its importance, few if any have had the kind of success that Kakalios has. His is like an experiment that worked backward: the results were overwhelmingly positive, and only now can we go back and try to examine what he did to produce them.

Kakalios was a professor and researcher at the University of Minnesota, teaching an introductory physics course that many non-science students would take. When those students got frustrated, they would throw down the all to familiar complaint, "When am I ever gonna use this stuff?!" Physics teachers hear this a lot and so they try to add things like car engines, solar panels and other "real world" examples to their lectures. But Kakalios almost never gets that response from students taking his superheroes class. Are all those kids going into the comic book industry - or is the "when am i ever gonna use this" complaint actually a diversion from something else. Maybe it's just a way to avoid their true feelings - that they simply find physics boring. Or worse, it just makes them feel stupid. Knowing this changes how teachers might approach this complaint.

Kakalios also discussed his experiences talking with non-scientists, and introducing himself as a physicist. He said that, quite often, people put up a wall when they heard his profession. He feels that people often assume they just aren't smart enough to engage in any kind of a conversation about physics, even if they have questions. When, in reality, a physicist might be equally befuddled by any number of occupations.

But when Kakalios discusses the physics of superheroes, people don't seem to put up that same wall. Instead, they begin to engage in a dialogue about physics.

Kakalios said in the Q&A period that the physics community is responding very well to his approach. The community is beginning to realize, he said, that it needs to communicate with the general public, and not just on an informational level. We want people to be excited about science. We want them to understand that it is an approachable subject. Because not all students who take a physics course will become physicists, but they will become citizens and voters. And voters can vote for science, get it?

That's my new sign off - "Vote for Science, Get it?!"

Read the rest of the post . . .

Thursday, March 25, 2010

Ten Great Stories from the American Chemical Society Meeting that DON'T involve Cold Fusion

I can't attest to the validity of any of these fascinating breakthroughs reported at the American Chemical Society meeting going on this week in San Francisco, but I also don't immediately see that any of them fly in the face of firmly established science.

So, here are ten things you could learn about at the ACS meeting other than cold fusion, starting with . . .

1. Inhalable Insulin




2. Preventing glaucoma with contact lenses embedded with vitamin E, and a test to detect the disease sooner



3. Saving the planet with hair conditioner




4. New radiocarbon dating does less damage to antiquities



5. New menstrual cramp drug goes to clinical trials



6. Smart roofs to save energy



7. Test detects three diseases that torment the developing world



8. Treating prostate tumors with walnuts



9. Detecting fake wine vintages by measuring atomic bomb residue



10. Safer sunscreen and other products from soybeans



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Wednesday, March 24, 2010

Let us discuss Wikipedia


I was going to write a post about a new word I learned at the March meeting (you will have to wait until next time to hear what it is!), but instead thought I'd talk about this afternoon's unnatural disaster. I'm sorry to have to tell you this, but Wikipedia has died.

Well, not died...sorry, I hope you didn't freak out just then. Wikipedia just had its (their?) servers overheat and shut down for about 2 hours. It appears to be back up and running now.

I must admit, those two hour period was dark for me. It left me feeling like a kid who's playmate is sick and can't come outside. I just feel safer when it's here. I miss it...I just want it back!

-SLAP!-

My brain reaches out and brings me back to reality. Aren't I, a hard-nosed journalist, supposed to despise Wikipedia? I feel like I am constantly reminded not to develop this kind of relationship with it. Such a relationship is sinful. If I give in to the temptation I risk having a big W burned into my chest.

So even though Wikipedia is like a childhood playmate to me, I guess it's like having a playmate who is also a pathological liar. He can't help it, and I guess you shouldn't hate him for it. But you know - don't buy insurance from him.

In Buzz Skyline's post yesterday about cold fusion, a commenter took a swap at Buzz for linking to a Wikipedia article. Buzz came back in very respectful form and let him know that the Wiki article was the most convenient for linking, but that he, Buzz, had been covering this subject for years. His sources were legit.

I find Buzz's argument valid. In the blogging world, and particularly in the science blogging world, sometimes Wikipedia is the easiest way to point people to a quick and dirty definition. Or sometimes it's the only place to find a page that directly defines something or gives its history.

As a science writer, I frequent Wikipedia. Let me say up front, I never use Wikipedia as a primary source. But it is a great place to start; it's easy to click around to related topics; I can use it to set up a framework of the topic in my mind; if the post is cited, I can find other reliable places to look. And once again, in the science world, it is quite often the only place to start.

I can't tell you how many times I've Googled a term from a physics paper, and come back with nothing but a list of research papers that usually only mention the word (they don't define it), some group of obscure documents, and, if I'm lucky, at the top of the page is a Wikipedia entry; glowing like a neon sign in the desert. It's possible that there are text books at the science library that would hold a definition, but not necessarily at the level that I need. And then again, a lot of these terms are very new and may not be in a text book anywhere. And I'm really sorry, but I can't get over to the library for every assignment I do.

If I can find a Wikipedia entry about a scientific term, I read it. I don't make it my primary source. My internet research is almost always followed up by an interview or email conversation with a scientist, and I need to have some information to start with. Sometimes whatever I think I know about the topic is unhelpful. But usually, it makes the interview go smoother. It allows me to ask more advanced questions instead of spending time establishing the basic framework (although I usually run my understanding by them and we correct it as necessary). It's best when the scientist can give me a paper or other document that I can reference. Wikipedia is the beginning, and it's a beginning that I appreciate having.

For that reason, I wish more scientists would contribute to Wikipedia.

The general public might not have the strict research rules that I do. In fact, some journalists don't even abide by those rules. It's been shown that journalists will use Wikipedia as a primary source, even if that Wikipedia page does not have citations. Which sucks.

But everyone else uses Wikipedia whether you like it or not. And quite often, it's a great place to find information. It is in no way perfect, and incorrect or un-cited information on Wikipedia has sparked internet rumors about things that never had backing to begin with. But in many cases it is a good place to satisfy an information craving. So if the general public wants to become educated on a weird science term they heard about, I bet about half the time they find their way to Wikipedia. I bet undergraduates who, like me, can't find a new term in a text book, also find their way there. I know at least one science writer who would love to find more links in Wikipedia articles to relevant papers, articles and websites, and scientists are probably the best people to add those.

It might also be beneficial for the field. I am constantly amazed at how far apart physicists of different subdisciplines and specialties are growing. In general, we need to talk about these things. And even physicists studying generally the same thing may come up with different terms to describe the same thing. It happens. This could definitely cause confusion when people try to communicate, and Wikipedia might offer just one place to make people aware of the discrepancy.

On a more basic level, there is no direct translation book written about all of physics. It's a language that has a lot of variation between specialties. It's a language translated from another language (math) and a language that is constantly making up new, necessary words every day. When I finally get to talk with a scientist, we try to translate their particular science into (somewhat) plain English. Sometimes we can do it with great success and sometimes we can't.

I'm doing my part to build the dictionary of scientific terms, but the scientists are churning out words, experiments and results faster than all us science writers can write. It will always overwhelm us. If scientists can help out a little, then why not?

Wikipedia is hopelessly flawed, and while I do not think we should try to make it a primary source, we must recognize that a lot of people use it as a source of information. So why not build it up? Why not add your two cents, especially if you happen to be an expert on the topic?

Don't crucify the Wiki for its being what it is, even if it's not what you'd like it to be. Embrace the fact that even if it's never authoritative, it could still be great.

Read the rest of the post . . .

Chemists taken in by Cold Fusion . . . AGAIN!

Ack! We were trying to figure out where the cold fusion proponents were at this year's annual March Meeting of the American Physical Society that took place last week. Unlike most years, there was nary a paper on cold fusion or palladium mediated nuclear transmutation, or whatever they're calling it these days.

It seems they were gearing up for the American Chemical Society meeting going on now in San Francisco. It's probably all for the best. The ACS embraces cold fusion with an inexplicable enthusiasm. As a former associate editor for one of their journals, that embarrasses me just a bit. (BTW, the photo above from the ACS press release about their cold fusion session appears to show one of the most pathetic calorimeters I've ever seen outside of a science fair.)

Yes, there are usually some cold fusion papers at our physics conferences, but that's because the APS allows any of its member to contribute talks, without peer review. It's all in the spirit of the open exchange of ideas in science. That's why there are also talks about zero point energy generators, perpetual motion machines, and a host of other fringe science topics, to put it gently. (In case you haven't seen it before, it's worth looking over the Crackpot Index right about now.) The thing is, the physical society doesn't endorse any of these topics, while the chemical society sets up press conferences for cold fusion.



I actually enjoy going to the cold fusion sessions, whether they're at physics or chemical society meetings, and I'm a little bummed that I missed the talks at the ACS session on Sunday. But I only go because I still remember the excitement that took the world by storm in my senior year in college, when Pons and Fleischmann held a press conference to tell us all our energy troubles were over thanks to their discovery. In fact, I still have a copy of their woefully incomplete paper that was faxed around the country at a breakneck pace just before their press conference in 1989. (That was in the dark ages before email took off as a major form of communication.)

In the days after the initial announcement 21 years ago, the excitement among both chemists and physicists was off the charts. The disappointment that followed, after we had a chance to let the news sink in, was just as extreme. As far as I know, the same problems with cold fusion that were identified back then still exist.

Yes, the payoff of an essentially inexhaustible energy source that runs on seawater is huge, but the science just doesn't make sense. All the wishful thinking in the world isn't going to change that.

Please, my chemical society friends, let it go. It's one thing for cold fusion scientists to present talks at meetings and submit papers to peer reviewed journals. But for heaven's sake, don't endorse this stuff with press conferences! Wait until one of them makes a working battery or something. Otherwise, you're raising the public's hopes for something that is broadly considered junk science at best, and is frequently fodder for con artists stealing money from retirees for worthless cold fusion energy schemes at worst.

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Monday, March 22, 2010

Frickin' Laser Beams

Francine Prose said in her novel Goldengrove that, “People see everything through the lens of their obsessions.” Case in point - a conversation I had a while ago with a six year old:

Me: Why are some of your ponies behind the toilet?
6: They live there.
Me: Kind of a gross place to live, isn't it?
6: They're in jail.
Me: Oh, so they're trapped there?
6: No, they want to live there but they're in jail.
Me: Wow, that's actually kind of deep. Why are these ponies smushed into that bar of soap?
6: They're married.

Note that all of this was told me with a tone of "Well, I think it's pretty obvious why they're there, but if I MUST explain it to you..."

I overheard a similar encounter between a physicist and a non-physicist on the topic of APS's Laser Fest, a year-long celebration of the laser:

Physicist: Lasers are responsible for so many technologies. They're probably the greatest, or at least the most prevalent invention of the last century. They're in, like, everything.
Non-Physicist: Like what?
Physicist: Bar code scanners.

While not said with the same tone that the 6-year old took, the physicist did seem to expect the non scientist to get excited about bar code scanners. Granted, they are great, but I don't think this example really captures the amazingness of lasers. Even many of the other laser applications that we see in our everyday lives (and hence use as examples when discussing them), like CD and DVD players, they seem to fall short in conveying the excitement that many physicists and physics enthusiasts have for lasers.

Physicists not only get to learn about laser applications, they often get to bask in the basic concept of focusing light into a beam, and a chance to contemplate the great potential that this invention has. The ideas have time to sink in. The seeds of wonder and awe have time to germinate and grow, until those feelings are built-in to our through process and we can't remember what it was like not to adore lasers. To know that lasers can cut through steel becomes even more amazing when you understand how they do it.

So I must wonder: Can I, as a scientist and a writer, ever hope to convey to the general public, the deep thrill that I feel for things I have had so much time to ponder? Can I, in the space of one blog post, light a fire of curiosity beneath my readers?

And just as I start to doubt my capabilities, I hit up the Laser Fest home page and scroll through the Innovations section, or look at all the awesome (seriously, awesome) stories in the news archive, and my faith is refilled. Treating serious psychiatric disorders? Removing body fat without surgery? Hopes for renewable energy? Etching a trade mark into individual Corn Flakes? Laser-powered space robots? Uncovering alien life? Controlling memories? A cure for blindness? LASER PONIES? It's all possible because of lasers!

And once again I feel that perhaps there is a chance of bringing my readers into this world of wonder and awe, because the evidence speaks for itself. Now do you see? NOW DO YOU UNDERSTAND WHY THE PONIES LIVE BEHIND THE TOILET?

Read the rest of the post . . .

Thursday, March 18, 2010

Space Flight Awareness

Guys, I want to talk to you today about something kind of serious. Something that affects all of us. I want to talk about Space Flight Awareness. Hey, don't give me that look, OK? Just level with me for a minute. I know that as your resident blogger you may think I am old and out of touch with the modern world. That I'm not hip to what's dope on the street. Well, you would be right. I have no idea how to talk to you about Space Flight Awareness without using a pamphlet from the 1950's. Which is why it's great that NASA has come up with these real-movie-inspired posters for their Space Flight Awareness campaign. Entertainment goes a long way towards education, that is what I say. Now I know there's a lot of them but please don't rush into choosing your favorite Space Flight Poster. You have plenty of time and trust me, you really want to love that poster before you choose it. Space Flight Awareness, guys.

Read the rest of the post . . .

Wednesday, March 17, 2010

Up In the Clouds


March Meeting madness is going strong here in Portland. Once again, if you're in the area tomorrow, the public lecture by James Kakalios on the Physics of Superheroes promises to be great.

On the meeting side, the number of talks this year is mind boggling (8000!). Through watching a handful of them so far I have come to two definite conclusions. Number 1: People are still using math. Liberally. Number 2. Physicists love to model stuff. Seriously, those folks will model just about anything. It's like catnip to them (in this analogy, physicists are cats).

One example is work done by Yong Wang of UCLS, modeling how fair weather clouds get their cauliflower like shape. (Wang and collaborator Giovanni Zocchi just had their paper accepted to PRL).

It's been known for a while that these fair weather clouds are formed when droplets of moisture hanging out up in the sky, are pushed up by thermal plumes coming from the ground. Those plumes tend to have nice little dome-like tops that put those cute little round bumps on the clouds.

What is new here is that although people generally knew that the clouds were formed this way, no one had modeled the system because cloud systems are very complex. So when it comes to physicist catnip, Wang and Zocchi make their catnip resemble very complex catnip in nature...ok that metaphor is falling apart. From the authors:

"What’s important about this work is that it describes (quantitatively) one specific aspect (the shape) of a complex system (the cloud) in terms of the coherent structures in the system (the thermal plumes). Usually one cannot do this with complex non-linear systems. In this case, this
procedure gives a simple description of a complex everyday phenomenon."

I did not know, going into the session, that fair weather clouds were formed this way. I also learned that although the plumes give clouds that cauliflower shape on top, you might notice that fair weather clouds tend to be flat on the bottom. You would assume that the plumes would make the clouds cauliflower-shaped all around. Well, they do. But it turns out that the flat appearance of clouds is created right at the point where the temperature gets high enough that the droplets evaporate. It's interesting that it can create such a distinct line.

When asked what this modeling could be good for, the researcher replied, "Video games." He suggested the models be used to create more realistic clouds in virtual worlds. The reporters wanted to know if there were climate or weather modeling applications, but Wang said no. No one asks a cat what else catnip is good for, but I hope other researchers can at least learn from Wang's modeling techniques and get something more out of this research.

(Photo courtesy of Michael Jastremski.)

Read the rest of the post . . .

Tuesday, March 16, 2010

A taste of the APS March Meeting: finance's fractal nature



Portland, Oregon. Not pictured: amazing physics breakthroughs.

At any time of year, Portland's charms—its scenic bridges, lush parks, microbreweries and the incomparable Powell's bookstore—would tempt me to visit. But I've never longed to be in that city as much as I do right now. The American Physical Society's March Meeting is in full swing, and I'm missing out on the hottest breakthroughs in condensed matter physics (the field that gave us the semiconductor, people!) and other strange and fascinating areas. I went to the April Meeting (held, counterintuitively, in February), and it was like a Vegas buffet—too much to choose from and not enough room (in this case mental) for all of the delicious physicsy goodness being offered. And if April is like a Vegas buffet, well, then March is like a Vegas buffet with extra sushi. Hopefully we'll get some nice tidbits in the coming days from our other bloggers, but they've already served a favorite dish of mine, so bear with me while I salivate from afar, as it were.

You may not expect to hear about the stock market at a physics conference, but don't underestimate what physicists are thinking about. H. Eugene Stanley calls himself an econophysicist—he coined the term—and appears to have a physicists' firm belief in not fooling ourselves when it comes to what we know, in this case, about economics. At a session titled, quite wonderfully, "Four Horsemen of the Apocalypse Redux: The Physics of Global Catastrophes and Global Countermeasures," Stanley presented work that I'm tempted to call "microeconomics," although that wouldn't be quite right. Instead of looking at grand, sweeping economic trends, he wanted to see what was going on at a scale that financiers usually ignore.


Big, jarring events in the stock market aren't outliers--they're just the same as the tiny tremors seen every second.

If you think our economy is too tumultuous to bear thinking about, try looking at the bubbling frenzy of stock prices and volumes microsecond to microsecond. Stanley analyzed 14 million German Stock Exchange trades, logged to the nearest microsecond, over a 9 month period, and he saw that trading sped up and increased in volume following periods of extreme spikiness, while lulls had a knock on effect on trading, slowing it down and decreasing the volume of trades. Disturbingly, he saw that the stock market has something of a fractal nature; surges and falls seemed to work this way, whether they're on the scale of a few seconds or months. So the booms and busts that take us by surprise really shouldn't at all. "The statistical properties of these 'outliers' are identical to the statistical properties of everyday fluctuations," he writes in his abstract. If the microscale financial world is a bubbling cauldron, we should expect to see the same dynamics when we zoom out to more practical length scales.

Stanley isn't your average economist by a long shot, but he's doing something extremely exciting: applying the bread-and-butter data-mining techniques of physics to a world that's pretty much only been thought about in the abstract. A glance at the list of papers he has on the physics preprint arXiv and you'll see everything from public debt to corruption, heady stuff for the director of a "polymer studies" center. As someone who's turned a career in physics to new subjects, he's almost the opposite of a very public economist. A recent profile of Paul Krugman asked whether the Nobel Prize-winning economist had anywhere else to go in his career. It also mentioned how Krugman berated fellow economists in a New York Times column last fall for failing to see the current crisis coming. I wonder whether he would find Stanley's approach to be an viable avenue for pushing economics to new levels of rigor and predictive power. Krugman's not likely to do much in academia anymore; profile even quotes him saying, somewhat facetiously, "If I do have some brilliant academic insight, what are they going to do, give me a Nobel Prize?" Maybe not in the same field, but why not?

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Sunday, March 14, 2010

Have some Pi for Einstein's Birthday

Q: What's the area of a circle?

A: Pi r squared . . . wait, that can't be right, pi r round, brownies r squared.


Sorry, that's my favorite, bad pi joke. I send it out to you in celebration of Pi-day, which also happens to be Albert Einstein's birthday.
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Saturday, March 13, 2010

Nico Turns 90 (and I was there!)

Talk about being in the right place at the right time – on Friday, March 12, 2010, I had the privilege and good fortune to be able to attend a conference and birthday party in celebration of one of the greatest physicists of the 20th and 21st centuries – Nicolaas Bloembergen.

He’s called Nico, turned 90, has a Nobel Prize, and is really nice. I had the pleasure of chatting with him briefly at “The Nicolaas Bloembergen Nobel Prize Scientific Symposium” sponsored by the University of Arizona College of Optical Sciences.

Nico is considered one of the fathers of optical science and in particular, lasers. In fact, the two last lectures of the day, entitled “Who (really) Invented the Laser (Part I and II),” presented by Robert A. Myers and Richard Dixon, offered evidence from patent filings that Nico is the true parent of the laser.

“By patent law, Nico is the (undeniable) inventor of the laser,” stated Myers, a former student of Bloembergen’s. He clarified that “inventorship of the laser goes with the patent, not the scientific paper,” and if historians looked at the patent they would know for sure who invented the laser. The patent to which he referred is called Bloembergen ‘654 and was given in 1959 for “Uninterrupted Amplification Key Stimulated Emission Radiation from a Substance Having Three Energy States.”

Myers noted that Claim 1 of the Patent is “one of the most beautiful claims I’ve ever seen and I’ve read thousands of claims. It covers all solid state and X-ray and gamma rays lasers. It’s clear and unambiguous.”

Although Myers and Dixon wrote about this in their 2003 paper “Who invented the laser: An analysis of the early patents” in the Journal Historical Studies in the Physical and Biological Sciences, Myers stated that he had actually given “the inventorship of the laser” to Nico on his 80th birthday. As a side, he thanked his former advisor “for forgiving me for asking for a raise” when he was a student.

Although there was nothing earth-shatteringly new about any of the speeches, they were fascinating nonetheless, as they delved into various aspects of optics and laser science that has been significantly influenced by Nico in some way. In fact, most of the speakers and even some guests had direct connections to Nico, either serving as his student or colleague at some point in time.

There were four Nobel Laureates in attendance. In addition to Nico, who shared his 1981 Prize in Physics with Arthur Shawlow for “for their contribution to the development of laser spectroscopy,” the others included:

--Roy J. Glauber, whose 2005 Nobel is “for his contribution to the quantum theory of optical coherence,” and with whom I shared a table at the dinner following the Symposium;

--John L. Hall, who also got the Prize in 2005, in conjunction with Theodor W. Hänsch, for “contributions to the development of laser-based precision spectroscopy, including the optical frequency comb technique;”

--Charles H. Townes, another laser pioneer, who shares his 1964 Nobel with Nicolay Gennadiyevich Basov and Aleksandr Mikhailovich Prokhorov “for fundamental work in the field of quantum electronics, which has led to the construction of oscillators and amplifiers based on the maser-laser principle.”

Among the 18 eminent speakers was Peter Sorokin. Sorokin, who in recent years has become very interested in the idea of natural lasers existing in stars (see … for an explanation), has examined 100s of spectra from various stars to prove his theory. During his presentation he thanked his former advisor, Nico, stating “he’s the man who started me in science in 1956 and I’m still trying in science. I may not be as good as I used to be, but I still have the spirit and it’s all thanks to picking the right thesis advisor.”

Sorokin has not published his theory yet. But after finishing his lecture, on the way out of the auditorium, Nico grabbed him and suggested some potential publishing outlets to him. Following that encounter, I had the chance to speak with Sorokin, who is a gentleman scholar, and offered to show me the spectra from 350 stars that proved his hypothesis.



(That's me with Peter Sorokin, the Inventor of the 2nd and 3rd lasers.)

I greatly enjoyed sitting in on the many other talks given by the Who’s Who of optical physics and lasers. Is it any coincidence that Nico’s 90th b-day is the same year as Laserfest, celebrating the 50th anniversary of the birth of the laser?


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Friday, March 12, 2010

Warning: loss of digits can be expected

A funny thing happened on the way to the physics demo. I thought I lost my finger. There was blood everywhere. I was in excruciating pain.

Before I get ahead of myself, let me assure you that in this instance my calamity had nothing to do with liquid nitrogen. Rather, the perpetrators were a busted fire extinguisher and inexperienced personnel. I won’t name names, but you can guess that the first letter of the first name of the staff member was “A”.

So from the top – it was a clear and beautiful day in sunny Tucson, AZ, and my colleague and I were preparing to do a series of physics demos for cherubic children on their way over from the local school. We weren’t presenting anything fancy, mind you, just the usual suspects – the Tesla coils/light sabers, Van de Graaff Generator, gyroscope seat, and of course, the fire extinguisher-propelled cart. Ah, the innocence of physics demos. What could possibly go wrong with a light bulb in a mouth, or for that matter, a seemingly angelic fire extinguisher?

In the morning, as we gathered our equipment and demos, my buddy realized that the extinguisher was low on the extinguishing material, which I believe was sodium bicarbonate. Having never used a fire extinguisher in my life, and eager as a young CERN tech to press the “on” button of the LHC, I volunteered to not only take the implement to the local supply house to have to refueled, but also to skip out back and try it out.

My colleague accompanied me and explained how the mechanism works. Ah, the purity of a person’s first fire extinguisher experience. We remember it forever. Mine was magical – I pulled out the pin, and, due to a malfunction, the nozzle spun around in light speed time and slammed into my hand. I howled in pain, my fingers throbbing, and I dropped the extinguisher on my foot. When I looked down, all I saw was red fluid gushing from somewhere on my hand. Additionally, I might have been dizzy because at first I didn’t see my fingers. Had I severed my digits? I wondered in a fog. Are they under my car which was parked nearby?

After blinking a few times and my comrade racing over to my side, I realized that my fingers were still with me. But why was I bleeding so much? Perhaps I had broken my hand. With the fire extinguisher lying somewhere helpless and empty in the loading dock, we jumped into my Honda and drove to the hospital. Turns out I just had a contusion. But I missed the physics demos anyway – those poor kids!

Because I worked for a university, I had to fill out a long form about my accident. Needless to say it would not be the last of these forms I would complete during my 12-year tenure. But fortunately, it was the last, that I can recall, in which I had to write: “contusion retained in the course of a physics demo mishap.”

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Cone Heads


If you happen to be in the Portland area next Wednesday, please stop into the APS March Meeting public lecture. Speaking will be none other than James Kakalios, the creative mind behind the book The Physics of Superheroes. It is truly a treat to watch him speak, and the talk is totally free and open to the public, so drop in if you can!

Although he wasn't the first to point this out, one of my favorite tidbits in Kakalios' book is the explanation of why Lois Lane would still die if Superman tried to catch her after she'd fallen thirty stories off a building. Ms. Lane's momentum and rapid deceleration would kill her - even if it was Superman's hunky arms that caught her, and not the sidewalk.

The challenge of finding a way to decelerate rapidly moving bodies, without crushing them, is the key challenge behind the physics of protective gear. We've blogged in the past about how helmets used in the military are saving lives, but also result in an increase of severe head trauma. And even designs in your basic bicycle helmets continue to evolve as we come up with creative ways to reduce the impact delivered to the wearer's head in a crash.

What appears to be newest of those designs just hit American stores. Straight from Australia comes the cone-head helmet.

The inventor, physicist Don Morgan, has spent twenty years working on the design, after studying the remains of helmets taken from crash sites. Here's a short description in writing, but you get more info from this video of Morgan accepting an award at the Australian New Inventors ceremony.


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Wednesday, March 10, 2010

Lookin' Good, Physics!

Let me start out by saying that I am a very hip and very in-touch young person. I live in the information and and I -

---HOLD ON. Got to answer this TEXT on my iPHONE. --

As I was saying, as a hip and in-touch young person, I am fully aware that information must be conveyed through multimedia if you hope to -

--- HOLD ON. Have to watch the latest VIRAL VIDEO on my MACBOOK PRO.--

Where was I? Oh yes; in order to get the attention of insanely hip and unbelievably in-touch young people like myself, you simply must cater to the fact that information is spread through -

--- HOLD ON. I must SYNCH my ipod and check out this WIFI.--

Do you see how hip and in touch I am? So as I was saying, you have to market yourself with multimedia if you hope to keep up with my generation. Which is why I'm so excited to see the photos that physicists have been submitting to accompany their talks at the APS March meeting. These are going on TWITTER!

These are genuinely stunning - I'm very impressed with this year's gallery. The one up top is from Roman Stocker and Mack Durham of (MIT), and comes with this caption: "Strong variations in marine currents form a watery trap for phytoplankton cells on their daily commute to the Ocean's surface." The one to my right from Greg Stone, Scott Mullin and Nitash Balsara of Lawrence Berkeley National Laboratory shows lithium metal dendrites growing through a polymer electrolyte for battery applications. The one below it from Adam R. Abate and David A. Weitz of Harvard University shows water drops within oil drops within water drops within oil drops within water drops dispersed in an oil carrier fluid.


You can see them all at the APS image gallery (seriously, go look! So many great ones!). Or you could join us in Portland next week and see the whole show.

These photos are so amazing that I think they will look awesome to people of all technological abilities! Even if you are the kind of person whose phone doesn't even have a color screen let alone a camera or the ability to connect to the Internet that finally died but you still tried to revive it and would not get a new one because you are scared someone will be able to watch you through it, and you could still appreciate these photos! I mean, THANK GOODNESS that is not a description of me, but either way...good photos! They deserve their own APP!

Now, I'm sorry but I have to go! I need to buy sunglasses that connect to facebook and throw my desktop computer off a roof or whatever. Great photos!


Noise fluctuations reveal quantum phases in ultra-cold atom systems. "Image courtesy of Anzi Hu/Joint Quantum Institute".

Visualization of human mobility networks showing short-range multimodal transportation and airline connections worldwide. Image courtesy of B. Goncalves, et al./Indiana University.


Tiny electrical microcircuits encased within single crystals of diamond; used to measure the physical properties of materials under pressures of up to several million atmospheres. Image courtesy of S.Weir and D. Jackson/Lawrence Livermore Lab and Y.K. Vohra and G. Samudrala/University of Alabama at Birmingham.


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Tuesday, March 09, 2010

New Unit of Energy from a "Godfather"

Watch out, Joule: there’s a new unit of energy measurement on the block that is oh so green.

The Rosenfeld, named after physicist and energy savings pioneer Arthur Rosenfeld, is defined as the electricity savings of 3 billion kilowatt-hours per year, the amount needed to replace the annual generation of a 500 megawatt coal-fired power plant, according to the press release from Lawrence Berkeley National Laboratory (LBNL).

There are 54 co-authors on the referred paper in Environmental Research Letters out today that suggests this new unit. Rosenfeld is considered to be a “godfather of energy efficiency” and has been “credited with being personally responsible for billions of dollars in energy savings,” according to Lab communications.

Rosenfeld received his Ph.D. in Physics in 1954 under Enrico Fermi, then joined the Department of Physics at the University of California at Berkeley. He worked with, and went on to lead, the Nobel prize-winning particle physics group of Luis Alvarez at Lawrence Berkeley National Laboratory. However he became very interested in energy usage and efficiency science, and in 1974, he began to focus his research in this field. He launched the Center for Building Science at LBNL and led it until 1994. The Center developed electronic ballasts for fluorescent lamps (which led to compact fluorescent lamps), low-emissivity windows, and the DOE-2 computer program for the energy analysis and design of buildings, for which Rosenfeld was personally responsible, as reported on the website of the California Energy Commission, for which Rosenfeld has served as a Commissioner for 10 years.

Now that he has completed two terms as a Commissioner, he is returning to LBNL to continue his research.

It is not every day that a new unit of measurement is announced, nor is it often that it is named after a physicist. Of course, this physicist already has a few terms named after him. The “Rosenfeld effect” clarifies “why California’s per capital electricity usage has remained flat since the mid-1970s while U.S. usage has climbed steadily and is now 50 percent higher than it was 40 years ago.” The term has been popularized by U.S. Secretary of Energy Stephen Chu, who has called Rosenfeld a hero of his, according to the press release.

There is also “Rosenfeld’s Law,” which states that the amount of energy required to produce one dollar of economic output has decreased by about 1 percent per year since 1845.

Ashok Gadgil, acting director of Berkeley Lab’s Energy and Environmental Technologies Division and one of the co-authors, says the timing of the Rosenfeld unit is particularly apropos. “We’re launching this definition at a time when we’re on the cusp, I think, from not worrying about carbon emissions to worrying like crazy about carbon emissions. It’s also a very practical way to think about energy resources.”

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Monday, March 08, 2010

Okay, Einstein, we get it. You were right.

As we've reviewed over the past few posts, Einstein's theory of relativity can be demonstrated by messing with the wavefunction of atoms, during an eclipse or when you are looking for super-far-away galaxies. In 1919, scientists held what I can only imagine was one of the most grand experiments ever - trying to observe the gravitational bending of light. The story surrounding it was so romantic: the expedition to South America, the ominous setting created by a full eclipse, searching for a signal from such distant objects, and of course, finding that the results were so overwhelmingly positive. I find this story breathtaking, so I hope you won't mind me telling you another tale of confirming Einstein's theory of relativity.

This one has to do with another arena that I particularly enjoy investigating: the solar system. The solar system has proved to be such a wonderful playground of discovery. It was where Galileo, Copernicus, and Kepler not only began to lay the ground work for modern day physics, but challenged the institutions that would have science silenced. The solar system is also where I did some of my own first experimenting - working out the mass of Jupiter based on the motion of its moons.

If you watch Mercury in the night sky - and you happen to catch it during the right time of year, you'll notice a funny thing: MERCURY GOES BACKWARDS!! Or at least, it appears to do so. (The image to the right is actually of Mars, but the apparent retrograde motion is the same. It looks like the planets do a loop!)

For many hundreds of years, this motion of Mercury confounded astronomers. That's partly because they believed that the Earth was the center of the solar system. When Copernicus generated the sun-centered model of the galaxy, Mercury's retrograde motion made a little more sense. Like cars on a freeway (or, in Copernicus' time I guess that would be horses on a dirt road? Or something?) the car you are in may at times appear to be stationary, while other cars appear to move in the same or opposite direction. Cars going slower than you appear to move backwards, while those moving faster appear to move forward.

So Mercury changes speed. It appeared to move forward because it travels faster than us, and then appears to move backwards because it moves slower than us. But WHY?

It wasn't until Kepler drew up the theory of elliptical orbits that we began to understand that planets do not travel at the same speed all the time. His 2nd law states that they will sweep out equal areas in equal time: meaning that as they travel further away from the sun, they go slower. So Mercury would zoom past us as it traveled close to the sun, but appear to move backward when it reached the furthest part of it's ellipse and goes slower.

BUT that still wasn't enough to totally explain what was going on.

The planets don't live in a vacuum. No, wait, they DO live in the vacuum of space. What I mean is, they don't live unaffected by the things around them. The motion of a planet is affected by the gravitational pull of the sun as well as the pull of the other planets. Trying to predict the motion of Mercury required taking into account all of these effects, and yet, Newton's prediction fell short. It was close - but it's imprecision was one red flag that something was missing in the classical interpretation of the universe.

Einstein's theory would eventually show that in addition to pulling two heavy objects toward each other, gravity warps the fabric of space time and has some effects which can't be predicted by classical physics. In this warped space time, planets do not orbit in a fixed ellipse, but can progress, creating a "flower petal" motion of Mercury. The planet's perihelion (the point where it is closest to the sun) changes, moving forward each time it moves.To totally predict this motion took Einstein's theory of relativity.

Einstein's theory was quickly shown to account much more precisely for the motion of Mercury - showing that every twelve million orbits, it's perihelion makes a full 360 degree turn. Here's a good site if you' d like some more technical and in-depth explanation for how Special Relativity predicts Mercury's motion.

We have covered how Einstein's theory of relativity is correct, and how it has been proven in the past. I know some of you may be aware that the theory of relativity is not perfect. There are extreme places in the universe where we believe it breaks down. But those, I'm afraid, are for another blog post.

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Saturday, March 06, 2010

Physics Party Tricks

Depending on the sort of parties you go to, here are two tricks to entertain your friends.

I prefer parties where this trick would be a hit.



This one isn't my cupa tea (or glassa wine), but I'd probably resort to it if the conversations were dull enough.


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Thursday, March 04, 2010

I Heart Particle Accelerators!


There’s great news, nay stupendous news, that should be tweeted and facebooked immediately. Turns out, physics can actually benefit society.


How’s that for a page-turner?


I learned this at the American Association for the Advancement of Science meeting in San Diego a few weeks ago. And yes, I sat on the news for all this time. Please don’t hate me.


The session where this bulletin was revealed was curiously not a press conference. Rather, it was a group of symposia entitled Particles and People: How Basic Physics Benefits Society, and in it I discovered some very critical information about the science in general, and about particle physics and accelerators specifically.


Yes, we all have been hit over the head 100 times about the impending black hole to be created at CERN that’s going to swallow us up, and the related anti-matter or “God Particle” that will wipe us and the planet away which the documentary “Angels and Demons” courageously exposed. But here I found out other invaluable tidbits about why we should really care about particle physics and accelerators. The session was presented by Elizabeth Clements and Katie Yurkewicz of Fermi National Accelerators Laboratory, and their information was echoed at the US Department of Energy’s Accelerators for America website. Accelerators are awesome because they contribute to:


Semi-conductors: This sector needs accelerator innovation to embed ions on silicon chips which ensures they are more useful in consumer electronic products such as computers, cell phones and MP3 players.


Clean air and water: Research demonstrates that “blasts of electrons from a particle accelerator are an effective way to clean up dirty water, sewage sludge and polluted gases from smokestacks.”


Medical diagnostics: Accelerator technology is used to produce various radioisotopes for medical imaging and treatments.


Pharmaceutical research: “Powerful X-ray beams from synchrotron light sources allow scientists to analyze protein structures quickly and accurately, leading to the development of new drugs to treat major diseases such as cancer, diabetes, malaria and AIDS.”


Cancer therapy: “When it comes to treating certain kinds of cancer, the best tool may be a particle beam. Hospitals use particle accelerator technology to treat thousands of patients per year, with fewer side effects than traditional treatments.”


There are quite a few more reasons to fall in love with particle accelerators, but one really stands out in my mind. When I first walked into the room where the session was taking place, there was one more benefit which the speaker was highlighting: Particle physics has helps keep my butterball turkey fresh. The real truth is that the shrink wrap used for turkeys and produce, as well as commercial products such as CDs and DVDs, is created using particle accelerators.


Now that you know, how could you not heart particle accelerators?


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Wednesday, March 03, 2010

Right the first time, Einstein

Following up from Wednesday's post, I wanted to take you all back to 1919 when Einstein's theory of relativity was demonstrated through experiment for the first time. It's an interesting story, and a more detailed account is given here.

The theory of relativity basically states that everything is relative to the observer. Even time. There is no absolute frame of reference where we can find out what time it is according to the universe. While time is a very important part of the universe, it can change for different folks moving at different speeds or living different distances from black holes.

Relativity also posited that gravity can bend light. So can a glass of water
(see the photo from PercepZone), but this was still a pretty freaky idea.

The only thing near enough to Earth with enough mass to bend a beam of light with its gravity would be the sun. But, the blinding light of the sun makes it nearly impossible to see the light of a star go anywhere near it. What to do?

Astrophysicist Sir Arthur Eddington had the great idea to try to look for the light-bending effects of gravity during an eclipse. If the sun passes between our telescopes and the light of a star, the gravity of the sun's mass will bend the light. If we can block the light coming from the sun, we can see these bending effects.

A six minute long eclipse took place in 1919, although total coverage was only visible in the southern hemisphere, so expeditions were sent to Africa and South America to watch it. The results confirmed Einstein's prediction.

Today we still use this concept to measure distances to far away objects. SLAC National Accelerator Laboratory just put out this awesome video to illustrate the concept. Scientists from SLAC also just published a nice paper showing that the method (called gravitational lensing) is just as precise as other methods of determining astronomical distances. Enjoy!

video

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