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Chu's Final Breakthrough Before Taking Office
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."
In case you're an idiot like me, you might appreciate to know that interferometry is about studying the properties of two or more waves by looking at the pattern of interference created by their superposition. The instrument used to interfere the waves together is called an interferometer.
What, you don't remember this stuff from Physics 101? Shame on you...
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Chu is a popular name, you insensitive clod.
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.
...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.
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.
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?
What's more, he's replacing a typical D.C. corporate revolving-door appointment, Samuel Bodman. 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.
O lord, bless this thy holy hand grenade, that with it thou mayest blow thine enemies to tiny bits, in thy mercy.
Err, he is the director of LBNL, so I would assume he would be a good manager as well as a good scientist.
All your base are belong to Wii.
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.
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.
Fudge factor G: to say that m_inertial = G m_gravitational is to say that there's a linear relationship between them (and normally you think of G as the coupling constant and say m_i = m_g). A priori, there's no reason there had to be any sort of relationship between them, much less a polynomial or a linear one. Take for instance electric charge, where the analogue of m_gravitational is q_electric, which can be anything whatsoever, independent of m_inertial. It's the fact that there's a relationship at all - and that it's such a simple one - that is so bizarre, and which has led scientists from Galileo on to test the equality, made Newton confess he hadn't the foggiest why it might be true, and led Einstein to his Equivalence principle.
i have to break it to y'all ... but this isn't really steve's work. of course he's a genius, but no one (including the press) has mentioned that the last author is Holger Mueller. in the (physical and biological) sciences there's a fairly well established protocol that the first author is the one who did the actual work and the last author is the leader of the project. of course, there's exceptions to the rule and these are always stated in the footnotes.
i think this is an example of the press just trying to use someones name to get more attention.... as usual.