Lawrence Berkeley Lab's TEAM 0.5 is capable of resolving individual carbon atoms in the honeycomb crystal structure of graphene. See QUEST's video The World's Most Powerful Microscope for more information. Image source: Nano Letters

Fifty years later, a new field of nanotechnology has exploded. At the cutting edge, researchers are successfully manufacturing everything from corporate logos to radios that are all small enough to be stacked end-to-end perhaps a million items long across the proverbial head of a pin. The advent of personal computers and smart phones has brought the power of such miniaturization into sharp focus for the general public. In a very real sense, we have all become bottom feeders. Below is a brief progress report on the state of the field.

Microscopes: The old adage “seeing is believing” was not lost on Feynman back in the late fifties. He noted that many of the most fundamental questions in biology could be readily solved if we only had the ability to see the molecules directly. Today, new inventions such as the scanning tunneling microscope (STM), the atomic force microscope (AFM), and the transmission electron microscope (TEM) have all achieved resolution at the scale where individual atoms can actually be seen and manipulated.

Miniature Motors: Perhaps the speech’s most imaginative scenario, due to Feynman’s friend (and graduate student) Albert Hibbs, was the concept of being able to “swallow the surgeon.” Feynman imagined that we might some day be able to construct robots capable of repairing or investigating the inner reaches of an ailing patient’s body. Mixing engineering and biology like this can run quickly into thorny ethical questions. Nevertheless, interesting progress has been made. Researchers in Alex Zettl’s group at UC Berkeley have recently constructed a nano motor, for example.

Information Storage: Using order-of-magnitude arguments, Feynman argued that the Encyclopedia Britannica could be squeezed into a pin’s area if the text were reduced by a factor of 25,000. He offered a $1,000 prize to the first person capable of printing one page of any book at this scale. Tom Newman, a graduate student at Stanford, first accomplished this in 1986 with an impressive reprinting of the first page of Dickens’ classic A Tale of Two Cities. Today, you can buy the book in its entirety for only 1.9 megabytes. For a high-end smart phone with 30 gigabytes of memory, you could perhaps hold 15,000 books within the palm of your hand. Not bad.

Then again, at the extreme limit, Feynman also reasoned that you ought to be able to squeeze the text of every book that has ever been written (now more than 32 million titles according the Library of Congress) within the confines of a single speck of dust. We still have a long way to go.

The Sloan Telescope used to conduct BOSS

One of those is BOSS, the Baryon Oscillation Spectroscopic Survey, is a new project to create a 3-D map of over 2 million galaxies and quasars representing the best data ever obtained on the large-scale structure of the universe. Baryon oscillations began as pressure waves through the hot plasma of the early universe. Those waves left an imprint on the matter that makes up the universe, including the dark matter. The survey will essentially act as a ruler, in order to measure how the universe has been expanding.

Next Monday, you’ll be able to meet David Schlegel, the principal investigator of BOSS. He’ll be part of a panel of Lawrence Berkeley Laboratory scientists discussing their search for dark energy. As a primer, check out QUEST’s story on Dark Energy from last year. The piece features astrophysicist Saul Perlmutter, who will also be speaking at the event.

See QUEST's Video on Dark Energy below:

QUEST on KQED Public Media.


Dark Secrets: What Science Tells Us About the Hidden Universe

Where: Berkeley Repertory Theater, 2025 Addison Street, Berkeley

When: Monday, October 26th 7-830 PM

Cost: FREE

Details: No mystery is bigger than dark energy — the elusive force that makes up three-quarters of the Universe and is causing it to expand at an accelerating rate. KTVU Channel 2 health and science editor John Fowler will moderate a panel of Lawrence Berkeley National Laboratory scientists who use phenomena such as exploding stars and gravitational lenses to explore the dark cosmos.

A scanning electron microscope image of an invisibility cloak recently fabricated by Valentine et al. at UC Berkeley. The inset at lower right shows a close-up of the triangular cloak and the corresponding bump that the experiment worked to conceal. Reprinted by permission from Macmillan Publishers Ltd: Nature Materials 8, 568 – 571, copyright 2009.

While invisibility has been largely the stuff of fiction and allegory, that may only be true a short while longer. Two papers published by groups at UC Berkeley and Cornell have recently demonstrated that objects can now be rendered invisible at wavelengths nearly (but still not quite!) short enough to fool human eyes. The technique has come to be known as optical cloaking.

How does it work? Essentially, cloaking makes an object appear invisible by wrapping the object in a metamaterial designed to bend light. Such bending is common in everyday life, seen for example when you look though a glass of water. The genius of a metamaterial is that it has been carefully crafted to bend light exactly to where it would have gone in the absence of the cloaked object. As a result, both object and cloak are rendered invisible.

In 2006, the first physical version of this concept was demonstrated at Duke in the form of a microwave invisibility cloak. It was not without limitations. Imagine a magic rug that, when wrapped around a standing person, makes the person invisible to only one color, and unfortunately not even a color you can see with bare eyes. You would need something like a radar detector to see how invisible they were. Nevertheless, it was stunning demonstration of the cloaking principle.

The push since this first demonstration has been to extend the properties of this to ever shorter wavelengths, and the Berkeley and Cornell groups (respectively headed by Xiang Zhang and Michal Lipson) have succeeded in doing that with a newly designed "carpet cloak." The new design works quite literally by sweeping an object under a rug. An irregular bump on an otherwise flat conductor is covered with the carpet cloak. Then, when light bounces off both cloak and conductor, the cloak rearranges rays of light to make it appear as if the entire surface were flat.

The cloaks of both groups are at best capable of concealing an object no bigger than a speck of dust, but they make up for it in other areas. The demonstrated cloaks may now hide objects from wavelengths as short as 1,400-1,800 nm. (The microwave cloak above is optimal at about 3.5 cm.) Cut that number down to 700 nm and you truly begin to render objects invisible to human eyes.

The prospect of such technology dazzles the imagination. Could we use such a cloak to hide spy planes? Ugly buildings? UFO landing sites? Jason Valentine, the lead author of the Berkeley group, said that more realistically the new technology could be used to refine defects in expensive electronics. However, because of the mathematical parallels between metamaterials and general relativity, some have even proposed that the new technology be used to test deep space theories related to things such as a black hole's event horizon.

Maybe Alien vs. Harry Potter isn't quite such an awful movie idea after all.

The renowned physicist Enrico Fermi (1901-1954)

If we can forgive Fermi for his sterility, it is hard not to marvel at his ingenuity. The official estimate of the bomb's power turned out to be only about twice as large, and it was this uncanny knack for being able to calculate unwieldy quantities that helped earn Fermi a reputation within the physics world.

The concept of the "Fermi Problem"–a hard question made readily accessible by back-of-the-envelope calculations and familiar knowledge–is still powerful in physics and beyond. Science teachers routinely use these types of questions as brain teasers. Economists at the World Bank have used the method to estimate the cost of a potential flu pandemic. The method has even been employed, in the form of the Drake Equation, to assess the likelihood of the existence of aliens. With a little effort, you can try it, too.

To illustrate, consider the classic problem, "How many piano tuners are there in Chicago?" The idea of the Fermi Problem is to break the questions down into a series of steps that you can estimate accurately. For example, I could start with the knowledge that Chicago has a population somewhere in the neighborhood of a million people. It seems reasonable that there is about 1 piano for every 100 people because I have about 200 Facebook friends, and of that group maybe 2 own a piano. This gives me 10 thousand pianos. Then I could assume that a piano needs tuning perhaps once a year, so there are 10 thousand jobs a year. If a piano tuner needs 100 jobs to stay in business, the city of Chicago has about 100 piano tuners. Amazingly, if you are careful you will almost always arrive at the correct answer to within a factor of 10.

The piano problem might be so obscure that no one cares about the answer even after you do find it. Here are a few perhaps more interesting questions, and my estimations:

Technology: At any given point in time, how many people are watching a Rick Astley sing, "Never Gonna Give You Up"? (YouTube shows about 20 million views for the video's current incarnation, posted 1 year ago. Given 30 million seconds in a year, and a typical patience level of perhaps 10 seconds, you can assume that 10 people are being Rickrolled right now.)

Energy: How many power plants does the City of San Francisco need? (It takes about a billion Watts, or 1 nuclear or coal power plant. As Richard Muller points out in his book Physics for Future Presidents, you can obtain roughly the same amount of power midday by covering a landmass the size of San Francisco with solar panels. Tempting.)

Food: How many people can the state of Iowa feed? (A bushel is roughly 35 liters, providing perhaps 10 people or more a day's worth of food. Iowa produced 2.4 billion bushels of corn in 2007, so given about 300 days in a year, that's 10 million bushels a day, or food for 100 million people, or 1/8^th of the world's starving.)

A magnet is suspended over a liquid nitrogen cooled
high-temperature superconductor (-200°C). Image source:
Wikimedia

This effect, known as superconductivity, has tantalized physicists with theoretical weirdness and seduced futurists with potential applications since its discovery in 1911. Some of the applications, particularly in magnetism, have already been realized. A typical MRI machine works because, hidden within its outer casing, electricity is pumped through a superconducting wire maintained 10 times colder than the average temperature of Pluto. The soon-to-be-running Large Hadron Collider at CERN in Geneva would not have been possible without the aid of giant superconducting magnets. Scientists at the High Field Magnet Laboratory in the Netherlands have even used superconducting magnets to suspend a living frog.

Even more exotic and exciting ideas have been dreamed up, such as large-scale lossless power transmission networks or commercially-viable magnetically levitated trains. Many of these have remained elusively beyond the cusp of practicality. This is because most materials become superconductors only in the frigid neighborhood of absolute zero (0-10 Kelvin). A few do have higher transition temperatures. For example, the cuprates, a class of material based on copper and oxygen, become superconductors as high as 133 Kelvin. Unfortunately, these are also brittle, difficult to work with, and bear limited current loads. However, times may be changing.

In February of last year scientists discovered a new candidate in their quest for a better superconductor, a material based on iron and arsenic. That's right– it is possible that one of the most promising candidates for next-generation energy technology is at least partly the same stuff Aunt Abby used to poison Mr. Witherspoon. The new class of material, collectively known as the iron pnictides (pronounced "NICK-tides"), has taken the physics community by storm, inspired more than a thousand research publications and stolen the show last month at the world's largest annual gathering of materials scientists, the American Physical Society March Meeting.

Is all the hype really merited? Maybe.

Much of the excitement surrounding the iron pnictides is becuase they turn superconducting at anomalously high temperatures, to date at least as high as 56 Kelvin. To be fair, this is still not exactly a high temperature compared to normal everyday experience. Room temperature is about 300 Kelvin. At 273 Kelvin you can get frostbite. At 56 Kelvin the air you breathe liquefies and your lung cavities fill with dry ice.

In the world of superconductors, however, a material with a transition temperature of 56 Kelvin is a rock star. This is the second warmest class of superconductor we know about, overshadowed only by the cuprates.

A few scientists feel optimistic that the pnictide family's transition temperatures may yet surpass even those of the cuprates. This would be a tremendous scientific and technological discovery, not simply because it would set a new record, but because it would mean that we now have two families of materials that become superconducting above the boiling temperature of liquid nitrogen (77 Kelvin). This would be fantastic because cooling materials with liquid nitrogen is both technically easier and less expensive than using the current standard of liquid helium.

Additionally, there may be reason to believe that the new iron pnictides may not have some of the problems that plague other high temperature superconductors. The cuprates have an annoying habit of spawning tiny electrical whirlpools in the presence of a magnetic field. Unless these whirlpools, or vortices (as they are technically called), can be pinned in place, lossless power transmission is impossible. While vortices still occur in the pnictides, pinning may prove to be easier than it is in the cuprates.

Even if we never are able to capitalize on the pnictides, they may have intrinsic scientific value. Scientists are baffled at the underlying mechanism that allows a material to be a superconductor above 40 Kelvin. Figuring this out may not ultimately satiate a desire for new technologies, but the simple desire to know is exactly the sort of thing that would make Darwin or Einstein proud.

Inside the Bevatron. Credit: Lawrence Berkeley National Lab.

Much as I tried to get Stewart Loken to wax poetic about the demise of the Bevatron, the truth is that he – and, I'll bet, a lot of scientists – just don't think that way.

As Loken put it, "science never stands still." However many Nobel prizes the Bevatron produced, this old, defunct particle accelerator is really just taking up space; its demolition, and replacement with a new, up-to-the-minute research facility, is, Loken feels, the best way to honor the work done here. Plans aren't finalized, but it's likely the facility to replace the Bevatron will forward work done at Lawrence Berkeley National Lab's Advanced Light Source (which, by the way, produces light a billion times brighter than the sun).

The new facility – described here – would allow scientists to watch "electrons joining forces, atoms snapping together within millionths of a billionth of a second, the real time of chemical reactions."

But that's a long way off. First, demolition workers must contend with a major disposal challenge, including getting rid of radioactive waste produced during experiments at the Bevatron. Some neighbors are concerned about the prospect of hauling the stuff through Berkeley's residential areas. Others have called for the Bevatron to be preserved as a national landmark.

But demolition is already underway, and picking up speed, thanks in part to $1.2 billion recently bestowed on federal research labs across the country under the American Recovery and Reinvestment Act. The Lab describes the environmental impacts of the Bevatron demolition project here.

See the Bevatron today and in its heyday – watch the "Goodbye to the Bevatron" slideshow online.

The Stanford Linear Accelerator. Credit: SLAC.

Luckily, there is a particle accelerator right here in the Bay Area. Last year, I took an intrepid group down to the Stanford Linear Accelerator (SLAC) to learn more about the these giant expensive research labs.

SLAC maintains an extensive public outreach program. An extensive tour (mine was 2 hours with very in-depth exploration of the facility), public lectures, weekly colloquia, and even science competitions for high schoolers.

I was surprised to find a wealth of research beyond the typical particle colliding at the facility. Many researchers use the state of the art facilities to study basic elements of our life, including water.

On Tuesday, Anders Nilsson is discussing his research on water at SLAC, an in-depth look at some of the stranger properties of water: its high heat capacity, how it is more dense than ice, even insight on using water as a power source (by splitting it into hydrogen and oxygen). Water: The Strangest Liquid, Tuesday February 24th 730-830PM at the Stanford Linear Accelerator.

However, our continued economics woes are threatening physical science research. SLAC is getting the brunt of money cut, missing out on $23 million of requested funding. In response, SLAC laid off 125 of its 1600 employees and shut down its PEP-II collider last year.

SLAC Public Lecture Series
The SLAC Public Lecture Series opens the doors to the inner workings of SLAC for the local nonscientific community. Find out what SLAC is all about: the research, the facilities, and the people that make this a world-class research institute.

SLAC Colloquium
The intellectual watering hole for the entire laboratory, where you can hear talks intended for a general audience on a wide variety of subjects. The colloquium will be returning later this year.

SLAC Science Bowl for High School Students
SLAC hosts an annual Regional Science Bowl for teams of high school students. The Science Bowl is a question-and-answer competition with buzzers, judges, and time keepers for high school teams of 5 students and 1 faculty coach. This year's competition is on February 28th.

SLAC Tour Information
Tours of SLAC will be available again later this year. On the tour, you get an extensive look at the operation of the accelerator, including a peek into the Klystron Gallery.

It’s true that the majority of the work done there is in support of Department of Defense and Department of Energy programs. But contrary to what one might imagine, the scientists there are work that goes on there isn't ALL about figuring out how to protect the U.S. from Communism. The scientists here are chemists, physicists and engineers who are delving into everything from warhead electrical systems to enhanced mammography.

We’re led into the "firing chamber" to meet our explosives guy, Jon Maienschein, who has promised to blow something up for us. I’m excited. It’s hard to make a bad TV segment when an explosion is involved. If you watch television, you will see that many shows live and die by that rule. Maienshein is surprisingly mild-mannered for a guy who blows things up for a living. After interviewing him for about 30 minutes on camera, we finally had a very basic understanding of what’s happening during a detonation.

There are several different kinds of explosions: chemical, natural, mechanical and nuclear, electrical, astronomical, etc. The most common "artificial" explosives are chemical usually involving a violent, rapid oxidation reaction. The fine folks at LLNL demonstrated just such and explosion for us then gave us the super-cool, ultra-slow-motion footage that they shoot in order to study what actually goes on inside an explosion.

We see or hear about explosions practically every day on TV, the movies and in the news, most people have no idea what an explosion really is. What’s happening on the chemical and molecular level? And how do the people who know about explosives actually study explosions? And why is it necessary to understand this stuff? The whole thing is surprisingly complex.

Watch the Inside an Explosion television story online.

Probably the hardest thing to get your hands on for this project will be the four gold-plated neodymium-iron-boron magnets. Not something you usually find at the local 5-And-Dime. (Or maybe I was just looking in the wrong aisle.) But I'm sure Make Magazine can point you where to get them. Once you do, here's a safety tip: The magnets are very powerful, so make sure they are securely taped down or they might slam together and shatter. Then you'll have to go out and find more gold-plated neodymium-iron-boron magnets.

Do try this at home. But be careful out there. Adult supervision is always a good idea. And make sure to aim your Tabletop Linear Accelerator away from your little brother.

Download Instructions for the Tabletop Linear Accelerator (419.3 KB .pdf)

Watch the Make At Home Tabletop Linear Accelerator television story report online.

The real physics of sailing are so deep and so complex, people
are still debating it.

It was another average Tuesday. I was sitting at my desk, looking at my calendar. Another day of budget meetings, returning emails, reviewing contracts, yawn. The usual buzz of production was going on around me, a crew going out to do a story about… sailing. Ah sailing, my favorite topic. My husband and I had recently moved both ourselves and our Tayana 37 up the coast from Long Beach. Okay, a well-qualified captain had actually moved the boat to San Francisco for us… but since Polaris had gotten here, we had become a bit obsessed about Bay sailing. Sailing in So Cal had not prepared us for the currents, tides and winds of the Bay, so we tried to get out there as much as possible.

Okay, back to Tuesday morning. The buzz moved over to my desk… the shoot was supposed to show a group of beginners on a sailing lesson, but the family that was booked for this purpose had suddenly cancelled that morning. Could I fill in? I considered my clothes… skirt, heels, not really sailing clothes. And moving all those meetings… but a day on the Bay… the beautiful, sunny, windy Bay. Plus, sailing with an instructor, there is always something to learn about sailing, how could I pass this up? Okay when are we leaving? No wait, what am I going to wear… isn't there a West Marine near the sailing school. Can we stop to get me pants and a pair of shoes? Yes, that's how much I really wanted to go out that day, I bought new clothes to do it.

It was a great day on the Bay. Stan, our instructor from the sailing school, was great at explaining the physics behind why a boat sails. At the direction of the producers, I asked every sailing question I could think of. Who has the right-of-way, what is this line for, what do we do when the wind blows harder? Okay, I knew many of the answers, but I babbled on anyway. Was I having fun? In much of the segment, I have the goofiest grin on my face. I wish I had a job that took me sailing every day…

Anyway, it was over too quickly – and then it was back to my meetings. But I'll tell you the biggest surprise of the whole experience: I though the physics behind sailing were pretty simple – a little Bernoulli Principle, a little lift generation. But what I learned made my head spin. It turns out that most of the simple explanations of sailing physics are ‘helpful models' that make sailing understandable to sailors. The real physics of sailing are so deep and so complex, people are still debating it. If you'd like to see what I mean, check out Arvel Gentry's website. Gentry was an aerodynamicist for 40 years, is an avid sailor, and an America's Cup boat designer. His technical papers will give you an idea of what's really going on:

http://www.arvelgentry.com