Chu's Final Breakthrough Before Taking Office 233
KentuckyFC writes "While preparing for the job of US Secretary of Energy in the incoming Obama administration (and being director of the Lawrence Berkeley National Laboratory and a Nobel Prize winner to boot), Steven Chu has somehow found time to make a major breakthrough in the world of atom interferometry. One measure of an interferometer's sensitivity is the area that its arms enclose. Chu and colleagues have found a way to increase this area by a factor of 2,500 by canceling out the noise introduced by lasers, which work as beam splitters sending atoms down different arms (abstract). One thing this makes possible is the use of different types of atoms in the same interferometer, allowing a new generation of tests of the equivalence principle. (This is the assumption that the m in F=ma and the m's in F= Gm1.m2/r^2 are the same thing). Let's hope he's got equally impressive breakthroughs planned for his encore as US Secretary of Energy."
Interferowhatsjiggy? (Score:5, Informative)
What, you don't remember this stuff from Physics 101? Shame on you...
Re:Any relation to Alex Chu? (Score:2, Informative)
Chu is a popular name, you insensitive clod.
For the Record... (Score:5, Informative)
From http://arXiv.org/auth/show-endorsers/0901.1819 :
Holger Müller: Is registered as an author of this paper.
Sven Herrmann, Sheng-wey Chiow and Steven Chu are not registered as owners of this paper.
Sure, it doesn't nail down who did what exactly, but if I had a question about the paper, I'm asking Holger first.
Re:Unfortunately... (Score:5, Informative)
...the article didn't say who did the work.
Just the politician whose name is attached to it.
unfortunately.. you don't understand whats going on.... the man being selected for the DOE position is a scientist, not a politician. And while preparing to become a politician, he still made progress as a scientist.
It says who did the work. Steven Chu. He will soon become a politician who has actually done something in life.
Re:For the Record... (Score:5, Informative)
According to http://arxiv.org/help/not-registered.html, Steven Chu may not be a registered owner for as simple a reason as not having a user account with that website.
That said, Mueller is listed as final author of the paper and Steven Chu is listed second to last, which pretty much throws all assumptions based on position out the window. (See http://www.phdcomics.com/comics/archive.php?comicid=562 for a comedic but sadly true primer).
Mueller served as a postdoc under Chu but both are professors. Based on Mueller's other publications (http://www.physics.berkeley.edu/research/faculty/mueller.html) and Chu's second-to-last position, I'd say the other two names are postdocs in his lab. Really, I'd ask those two if you want to know the specifics on this experiment. Blind guess at Chu's role, but probably functionally a PI - more of an adviser role.
Re:Wrong experience ? (Score:5, Informative)
He's the director of a research institute with over four thousand employees and a half billion dollar budget. I think he can handle the managerial stuff just fine.
Re:Qualifications (Score:5, Informative)
As has been pointed out many, many, ... many times before.
He's the director, as in, head honcho, manager type, of the Lawrence Berkeley National Laboratory, a Department of Energy funded facility. He's undoubtedly familiar with the rules and regulations of the DoE. In addition, he directs a staff over -over- four thousand scientists and management, and commands a budget -over- five hundred million dollars annually.
How is he not qualified, again?
Re:Unfortunately... (Score:5, Informative)
What's more, he's replacing a typical D.C. corporate revolving-door appointment, Samuel Bodman [wikipedia.org]. The man sat on his thumbs while energy prices trebled during Bush's time. He came from Wall Street ferchrisakes, and he'll probably head back to the corporate world, where I'm sure he'll be heartily welcomed for taking up the business agenda while at DOE.
With Chu, there's a pretty good chance he'll point DOE in a new direction, towards funded research for actual energy alternatives.
Good riddance to the Bush robber barons.
Re:Interferowhatsjiggy? (Score:5, Informative)
One of the neatest applications of this is the Michaelson Morely experiment. A the time of this work, theory was going back and forth between light as a wave and light as particle, and at the time light was a classical wave, which meant it needed a medium to travel, like sound needs air or water waves. It was theorized that the universe was saturated with an aether to carry the light. IIRC, it was theorized that as the Earth moved through the aether, there would be differences in the speed of light based on direction the light is going. In this work, a light beam was split, made to travel in perpendicular direction, and the difference in speed measured.
No difference was measured. this implied that no aether existed. this implies that the waves traveled without a medium. This was quite a surprising result, and was the beginning of the end for classical mechanics. 10 years later we had quantized energy, 15 years later we had the photoelectric effect tell us light was a particle, and a few years after that we have matrix and wave mechanics.
Re:Nice Change (Score:3, Informative)
Re:For the Record... (Score:3, Informative)
From http://arxiv.org/auth/show-endorsers/0901.1819 [arxiv.org] :
Holger Müller: Is registered as an author of this paper.
This means that Holger Müller is the guy who logged onto arXiv and uploaded the paper. It has nothing to do with who actually contributed how much to the research.
Re:I'm not a physicist but that is a terrible summ (Score:3, Informative)
Lasers work as beams splitters ?
Sending atoms ?
Um, yeah, right.
I'm not familiar with the details, but at first sight, I don't see a problem with those statements.
Remember, this is an atom interferometry. The "beam" refers to a beam of atoms. It's the wavefunction of the atoms that are being used to produce the signal, not the laser (which is the more garden-variety interferometry like one used in LIGO). From the description I get in the abstract, it sounds like they first laser-cool the atoms in a trap (probably magnetic, as the atoms used are frequently paramagnetic and can be trapped), then release the trap letting the atoms drop.
If you have a laser in the atom's path, by appropriately tuning the laser you can produce repulsive force on the atoms (I forget whether this has to be blue-shifted or red-shifted from the transition, but either way it can be done), so much like a rod in a stream, it will force the atoms to take one path or another as it drops under gravity.
The actual scheme in the experiment is probably way more complicated than this (they do claim factor of 2500 increase in the area covered, so the atoms must travel longer somehow), but it's nothing ridiculous. Maybe a little too technical for someone who's not an atomic physicist to grasp immediately.
Re:Interferowhatsjiggy? (Score:5, Informative)
I wonder if the noise this breakthrough removed was the same noise observed there or a ddifferent kind?
Neither. The world-as-you-know it is imaginary. The rest of us are really not here. All of this stimulus is being fed directly into your brain by a computer. You're in a coma, and not likely to recover. Sorry, dude. We'll make it look as close to real as we can. (Roll cheerleader porn).
Re:Nice Change (Score:3, Informative)
I work at LBL (as a guest, not an employee) and Steven Chu is very well-liked around here. He does have a rather disturbing laugh though.
Re:On a serious note... (Score:2, Informative)
not REALLY steve's work.... (Score:2, Informative)