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Showing posts from January, 2009

The Ethics of Atoms

Monday's broadcast of the Trials of J. Robert Oppenheimer recalled one of the most important debates in the history of physics. Historians use the Manhattan Project to debate the ethics of science and technology in society. Much of the arguments boil down to the question of what kind of role science plays in society and whether its used as a force for good or for ill. Some saw the devastation wrought by the atomic bomb as proof that science was inherently a destructive force in the world, while others saw the promise for cleaner and cheaper energy. The debate continues to this day, and draws in nearly every field of science.

Today scientists working on the latest atomic advancements, nanotechnology, are facing just as serious of a debate. There is a tremendous amount of potential in these cell sized machines, but what kind of potential depends greatly on one's attitude towards science. It's an important debate to have. Just as atomic energy proved to be the most powerful te…

Beware the Fine Print!

For anyone who has ever gotten tripped up by the fine print of a cell phone contract; watch out! Scientists at Stanford University have just created the world's smallest writing. These new letters are tiny, only about a third of a nanometer in size. I already have enough trouble figuring out my contract, if they start printing my roaming rates in words less than a thousandth of a millimeter high, I might just give up and revert back to carrier pigeons.

The team of scientists manipulated the quantum waves of an electron on a piece of copper so it would encode 35 bits per electron to encode each letter. A bit is the fundamental unit of computerized data, essentially a switch that signals either on or off. When multiple bits are combined, more complicated data like letters and numbers emerge. These wave patterns actually project a hologram of the letters outwards, which can be seen with a powerful microscope. What would a team of scientists from Stanford University write in the world&…

Factoids about Schrödinger's Cat

Weirdness is the name of the game for particles the size of an atom or smaller. Quantum particles exist in multiple states and positions at the same time. This can be hard to visualize sometimes, fortunately there's a couple of metaphors that can help out.

"Factoid" is one of the more curious words in the English language today. It was originally cooked up 1973 by author Norman Mailer while he was penning a biography of Marilyn Monroe as a word to describe "facts" that weren"t accurate. The suffix "-oid" means a "similarity, not necessarily exact, to something else," so by adding it to the word "fact," Mailer describes information that is accepted as true, especially by the media, but isn't

More to the point: In fact, a "factoid" isn't factual.

By cruel twist of fate, the use of "factoid" has been distorted to the point where its original meaning has been obscured. Over the years it's been misused …

How'd They Do That Tuesday: The Camera

Cameras are to the nineteenth and twentieth centuries what Gutenberg's printing press was to the fifteenth century. Both have completely revolutionized how information is conveyed. Cameras have captured everything from the battlefields of the civil war to the first moon landing into our homes and more. The first cameras over 180 years ago were not more than wooden boxes with a flap to let light in, but today cameras can capture images on film or digitally, still images or moving, microscopic or interstellar, at nearly any wavelength of light. However almost all cameras work using the same basic principles that they've been using since they were invented. Nearly all cameras share several similar components, a lens, a shutter, and recording surface, and they use these parts along with the physics of optics, to capture an image.


When you point the camera at a friend on vacation or a stunning landscape, the light reflected off of the subject will be collected by the lens. The lens …

New Year, New Podcasts!

Do you have any New Year's resolutions? Well, Physics does! Listen to the podcasts.

A Very Long Entanglement

A team at the University of Maryland was able to teleport the information of a charged a charged atom across a meter of distance last week. The actual atoms didn't move, however information about it moved a large distance instantaneously, as in faster than the universal speed limit, the speed of light. Though this might sound impossible, under the funky laws of quantum mechanics, weird things that don't make classical sense are commonplace. This wasn't even the first time scientists were able to influence distant particles instantaneously, but it's the first time an entire atom's information have been teleported.

The subatomic world of quantum mechanics is full of bizarre happenings and spooky events. One of the strangest goings-on is how particles can exist in multiple places at one time. In the very tiny world of quantum mechanics, particles don't necessarily inhabit a single point in space, but exist as a wave of probability. These waves express where a parti…

Can You See Me Now?

"I was working on the latest in invisible cloaking technology, but now I can't find where I put it."

What with the hullabaloo around here of the inauguration last week, this story nearly fell through the cracks. Technicians at Duke University announced that they have built a next generation cloaking device that could make objects appear to vanish. This new device improves enormously over previous light bending prototypes, and is a huge leap forward for the developing technology.

Cloaking devices work by bending electromagnetic waves around an object so it seems to disappear. When light hits the material the team created, the light gets redirected around an obstruction, and then released around the other side as if nothing ever happened. A spectator would see some distortion around whatever object is "cloaked" but it would be more like looking at a mirage than at a solid object.

A team at UC Berkeley developed a prototype last year that could hide objects from visi…

The Facts on Pollock's Fractals

What do you do when you inadvertently discover a huge cache of paintings that may have been created by the American master Jackson Pollock? Have all of them verified by experts? Naturally. Set up a world tour then donate them to museums? Of course! Maybe even fire up the calculator for some non-Euclidian geometry?

Not so fast on that last one.

About ten years ago physicist Richard Taylor created quite a stir in the mathematics and art world when he claimed Pollock’s works contained unique mathematical patterns in his brush strokes. Taylor said that these mathematical patterns were fractal, and so unique one could actually identify whether any given work of art was a genuine Pollack based on these patterns. Fractals are extraordinary complex geometric patterns where shapes and configurations infinitely repeat themselves.

However a new soon to be published paper dispels this idea of using fractals to identify and date a Pollack work. Physicists Lawrence Krauss, Katherine Jones-Smith and H…

Name that Scientist! New Administration Edition

President Obama's administration is chock-full of scientists. Kudos to all who can correctly name each scientist caricatured in this picture. And if you can't....take a peek at the article it came from.

The Physics of Crowds

What do the grains of sand in an avalanche and the people at the 2009 Presidential Inauguration have in common? There are so many small parts that the best way to understand how they all flow is through the physics of fluid dynamics.

The news is reporting that close to 2 million people crowded the lawn of the National Mall for the inauguration of Barack Obama. At the end of the ceremony, the throngs of people surged out seeking to get somewhere warm. I know because I was right in the middle of it, caught up in the flow.
That's what fluid dynamics is, the study of the flow of liquids or large numbers of particles, or even large crowds of people. Whenever there is a whole bunch of anything moving together, like a running river or an avalanche, certain patterns and organizations tend to emerge. Areas with a smooth flow or turbulence can be predicted accuratly based on the fluid's properties like viscosity or particle size.

The same is true with large crowds of people. Properties li…

How'd They Do That Tuesday (Friday Edition): Spectroscopy

[Note: Due to the long weekend, next week's How'd They Do That Tuesday is being brought to you early.]

As I wrote about earlier, scientists are now scrutinizing methane emissions on Mars to determine whether they were caused by microorganisms or some unusual geologic phenomenon. But the astute reader might wonder; how did astronomers on Earth discover Martian methane in the first place? Because of its orbit, Mars can be anywhere between 55 million kilometers and 400 million kilometers away from Earth. Not to mention methane is clear, how did astronomers "see" it? What gives?

Of course, physics has an answer. One of the most powerful tools in an observatory is called the spectrometer and astronomers use it to tell what elements make up objects very far away. It's a brilliant system that needs nothing more than visible light to work.

When light hits an object, some wavelengths are absorbed by the object, while others are reflected off, giving the object its color. Spe…

Of Mars and Methane

Yesterday NASA said during a press conference that there is a chance life may still exist on Mars.

WOAH!

Back in 2003 and 2006 the Earth based Keck Telescope in Hawaii detected huge bursts of methane gas on the surface of the Red Planet. After pouring over the data for years, the team of scientists analyzing these inexplicable events released their preliminary conclusions yesterday. NASA says these gaseous emissions are from either microscopic life forms or some unusual geologic phenomenon.

They're hedging their bets a little becasue the agency jumped the gun once before, when in 1996 they announced that tiny structures on a Martian meteorite could be fossils of extraterrestrial bacteria. The announcement caused a great sensation at the time, but over the years alternate explanations have shown to be equally plausible.

This time they're being much more cautious. In the words of team leader Michael Mumma, "Right now, we do not have enough information to tell whether biology or…

Bend it, Fold it, Twist it, Compute it

Molecules of carbon keep showing more and more promise for future use in electronics. This week scientists in South Korea demonstrated a process to make a transparent and flexible computer chip out of many interlinked carbon atoms. The days when we can wear our computers and keep the screens folded up in our pockets seems to keep getting closer and closer.

When carbon atoms are organized into a honey-comb patterned molecular structure they exhibit all kinds of exciting properties. They are great electrical conductors and are very structurally strong while still lightweight. When you roll them up into a cylinder, they're called carbon nano-tubes, and could possibly be used in everything from a space elevator to micro-circuts. If you keep the carbon honeycomb in flat sheets, it's known as graphene, and it's showing a tremendous amount of potential as the computer chip material of the future.

The team in South Korea was able to efficiently make these flexible nano-sheets by fi…

A Rose by Any Other Quantum Wave Function Would Smell as Sweet

Biology and quantum physics are two disciplines in science that rarely overlap. Quantum physics studies the strange workings of fundamental particles smaller than an atom, while biology looks at much larger chemical interactions and living organisms. However new unconventional research suggests that something as mundane as stopping to smell the roses is made possible by processes that bridge that gap.

Roses grow by using chlorophyll to convert sunlight into food through photosynthesis. However a recent study of photosynthesis of green sulfur bacteria found that these tiny microorganisms might just use some quantum weirdness to help transfer that food energy efficiently. Energized electrons travel through the myriad of connections within the bacterium's single cell transferring energy throughout. Electrons, which are quantum particles, can literally exist along a wave function at multiple points at one time. Only when someone (or something) seeks to measure them do their wave functi…

How'd They Do That Tuesday: The Physics of Bicycles

I'm starting a new feature this week called "How'd they do that Tuesday." Each week I'll pick out some cool widget or doodad possibly even a thingamajig and take a close look at some of the physics that makes it work. So for my inaugural run, what better place to start than with a subject near and dear to my heart: Bicycles.

Bicycles are elegant machines wholly governed good old fashioned classical mechanics. No fancy quantum probability waves or relativistic space time curves here. Right now, some of the oldest and most basic laws of physics are all that we need when talking about the bicycle, starting with Newton's second law of motion:

Mass (M) x Acceleration (A) = Force (F)

Essentially whatever energy you put into the bicycle, is what you'll get out of it. When you push down on the pedals with whatever amount of strength, the bike will then accelerate proportionally to that, depending on the bike (and rider's) weight. That way if I weighed 70 kg and…

Top 5 Discoveries of LAST WEEK!!!

Last week the American Astronomical Society had their big annual meeting, full of groundbreaking discoveries. I already mentioned our home galaxy is both bigger and spinning faster than we thought before because it was too big news not to mention it. Now that the conference has finished up, I can go through and give you my five favorite discoveries.

5) Black Holes Preceded Galaxies – Since astronomers first determined that gigantic black holes live in the center of most galaxies they've been trying to figure out which came first. Did the large cluster of stars in the middle of a galaxy collapse causing a black hole to form, or did the black hole already exist and pull stars in around it. Astronomers have found that the mass of a black hole in the center of a galaxy is almost always one thousandth of the mass of all the stars in the galactic bulge. However when one peers to some of the farthest and oldest galaxies, the black holes at their center are much bigger proportionally, lea…

Sometimes Even Scientists Have to Just Say "Huh?"

Some days Scientists just have to throw up their hands and admit that they just don’t know why something is happening the way it is. I love it when this happens, not because I like seeing exasperated physicists (though it can be pretty funny sometimes), but because it shows that there's still so much left in the universe to discover.

That's what happened this week when scientists from the Argonne National Laboratory announced that they really just don’t know why certain metals can transfer electricity without resistance at relatively high temperatures. They’ve got some guesses sure, but right now that's all.

When one freezes most materials down to super-cold temperatures (within a tiny fraction of a degree above absolute zero) a strange phenomenon sets in. Magnetic fields stop going through the object and electrical current is able to flow without any of resistance. This is called superconductivity, and even with these near zero temperatures, it's a hot field for study i…

Happy Birthday Stephen Hawking!

Today we celebrate the 67th birthday of Professor Stephen Hawking, perhaps the most brilliant mind alive today. He's been one of the greatest contributors to advanced physics and cosmology over the last half century, even after having been wheelchair bound for many years because of Lou Gehrig's Disease. At the same time, he has been a tireless advocate for scientific research all the while reaching out to involve the public. His book, A Brief History of Time stayed on the London Sunday Time's best sellers list for 237 weeks straight, making it the most popular physics book in history.

He first exploded on the scene in the late 1960s by helping to prove that black holes, massive gravity wells in space named because not even light can escape, were predicted by Albert Einstein's general theory of relativity. At the center of every black hole is what's called a singularity, an infinitely small and infinitely dense point in space that gives the black hole its mass. Hawki…

What in the Heck is "Quantum Computing" Anyways?

The field of quantum computing is a major area or research in physics. Nearly every week a new discovery is made that helps to lay the groundwork for newer developments. But what exactly are quantum computers, and more importantly, how much longer will it be until I can upload my iTunes on to them?

Unfortunatly the answer to the second part is not for a long while. As to what a quantum computers actually are needs a quick look at what quantum physics is.

On the scale of the extremely tiny (we're talking one billionth of a meter and smaller, as in atom sized) particles behave very differently than what we're used to seeing all around us. Fundamental particles, such as photons and electrons, can exist in literally more than one place at a time. Their positions aren't described as a single point, but as a wave of probability, also known as thier superposition. They exist simultaneously at every point along the wave until someone or something measures their location. When this …

Milky Way Galaxy 2.0

Imagine living in one city for all of your life. After a while you get to thinking you had a pretty good grasp about where things are, what the streets look like and so on. Then one day you realize nearly everything you thought you knew about home needed to be redrawn. Turns out, your home city is much bigger, shaped differently, spinning faster and… um… more likely to collide with the next nearest city. Pretty disorienting huh? Ok so my city metaphor sort of breaks down there at the end. That being the case, what I just described is almost exactly what's happened with our home galaxy, the Milky Way this last week.

A galaxy is a massive cluster of stars, many thousands of light years across, and they come in numerous different shapes and sizes. The most common kind of galaxy is elliptical in shape however the one we live in is more of a couple of spiraling arms with a bulge in the center. Because we don’t have the technology yet to travel outside the galaxy to map it, astronomers h…

What Do Broomsticks and Rockets have in Common?

Under normal circumstances, broomsticks and rockets have nothing (that I can think of) in common. But at the December 2008 Space Elevator Conference in Luxembourg, these trusty sweeping untensils get the job--of going to space--done.
European Space Agency engineer Age-Raymond Riise used a broomstick and an electric sander to demonstrate how a hypothetical "space lift" or "space elevator" might pull its cargo mechanically. The project could see a 100,000km long cable anchored to the Earth as a means of cheaper transportation to space.
I wrote about the concept of a space lift a few months ago. The simplicity of the idea, combined with the numerous and complex hurdles in technology needed to morph a project like this into life is what fascinates me. I suppose it's a prime example of the notion that "old" ideas aren't necessarily bad ones to be quickly tossed out in favor of the completely innovative; they can be modified and applied to new situation…

Year of the Stars

2009 heralds the Year of the Ox according to the ancient Chinese calendar. However, the International Astronomy Union and UNESCO declared it is also the International Year of Astronomy. This year marks the 400th anniversary of the birth of modern astronomy and what better excuse is there to party with the stars?

Over the next twelve months, museums, governments and astronomy enthusiasts all over the globe will be publicizing and promoting the stars and planets above. The planned events include everything from teaching the science of outer space, to exploring how astronomy influenced societies and cultures over the millennia. Some events will utilize the very latest in internet technology while others will go back to the first telescopes, all with the intent to get people excited about astronomy. Already 135 countries are officially involved, with more expected to sign on as the year progresses. There are many ways to get involved either on your own or along with any museums or universi…