Thursday, March 1, 2007

A Yogi In Time

Image credit: NIST

Philosopher and sometime baseball player Yogi Berra is alleged to have once described time as "what keeps everything from happening all at once". As with many of his utterances, this one is as elegant a description as anything people with PhDs could come up with. One thing that definitely isn't occuring at the same time is the end of the Libby trial and the verdict. We're now at seven days and counting. The jury are back at their deliberations, and may be let out early today if Judge Walton agrees.

Today's clock is a "chip scale" atomic clock introduced by the NIST back in 2004. "Chip scale" means it's about the size of a typical integrated circuit. Someday, you may have one in your house and you'll never have to set the thing again (as long as you remember to change the batteries, of course):

The heart of a minuscule atomic clock—believed to be 100 times smaller than any other atomic clock—has been demonstrated by scientists at the Commerce Department’s National Institute of Standards and Technology (NIST), opening the door to atomically precise timekeeping in portable, battery-powered devices for secure wireless communications, more precise navigation and other applications.

Described in the Aug. 30, 2004, issue of Applied Physics Letters, the clock’s inner workings are about the size of a grain of rice (1.5 millimeters on a side and 4 millimeters high), consume less than 75 thousandths of a watt (enabling the clock to be operated on batteries) and are stable to one part in 10 billion, equivalent to gaining or losing just one second every 300 years.

In addition, this “physics package” could be fabricated and assembled on semiconductor wafers using existing techniques for making micro-electro-mechanical systems (MEMS), offering the potential for low-cost mass production of an atomic clock about the size of a computer chip and permitting easy integration with other electronics. Eventually, the physics package will be integrated with an external oscillator and control circuitry into a finished clock about 1 cubic centimeter in size.

NIST Unveils Chip-Scale Atomic Clock

Some of your tax dollars really are spent well. How does it work? Well, like this:

The new clock is based on the same general idea as other atomic clocks such as the NIST-F1 fountain clock—measuring time by the natural vibrations of cesium atoms, at 9.2 billion “ticks” per second—but uses a different design. In the chip-scale clock, cesium vapor is confined in a sealed cell and probed with light from an equally small infrared laser, which generates two electromagnetic fields. The difference in frequency of these two fields is tuned until it equals the difference between two energy levels of the atoms. The atoms then enter a “dark state” in which they stop absorbing and emitting light; this point defines the natural resonance frequency of cesium. An external oscillator, such as quartz crystal like those found in wristwatches, then can be stabilized against this standard.

The important point is that the resonant frequency is a well-known physical constant, and once it's reached that frequency, it will tend to stay there.

The NIST Small Clock program is continuing to refine this design, and maybe we'll start seeing products based on this technology in a few years.

There sure are plenty of examples of how our tax dollars are being spent badly these days. One of the more blatant has been the recent unjustified firing(subscription or watching an ad required) of eight U.S. Attorneys. In at least one case, a U.S. Attorney was replaced by a political croney of President Bush's. shoephone has a great summary of the story and the latest inklings that Congress may finally get involved.

Meanwhile, Brent Budowsky opines that things aren't going so well at Walter Reed these days. SusanUnPC notes that soldiers there are being told to shut up, and the general in charge has been fired. Interestingly, no one in the Congress or the Administration have yet been fired for funding the place at a far lower rate than needed, nor have they been fired for ignoring many of the underlying problems for years. Senator Jack Reed made this observation, according to Reuters:

Sen. Jack Reed, who served as a captain in the U.S. Army, said after a closed-door meeting of senators with Gates that Weightman's removal was not enough on its own.

"I think they have to go further in terms of establishing responsibility," said Reed, a Rhode Island Democrat. "It's not just about firing individuals, its about fixing the problem."

U.S. Army hospital chief removed from post

I'll just add that telling the people who are suffering under this system to shut up isn't enough, either. In contrast to the civilian world, in the military comanders are held responsible for just about anything that happens in their commands. If it's shown they didn't try to correct the problems, they are usually treated as Gen. Weightman was. That's fine, we could probably use a little more of that on the civilian side of government. But Sen. Reed is right, what's really important is fixing the problems, and it sure looks like SecDef Robert Gates is mainly interested in punishing those "responsible" for this problem - the ones who are stuck with it, in other words. Things will only get harder as more wounded and disabled soldiers return from Iraq and Afghanistan.

UPDATE: (10:15AM PST, Mar. 2) No news either at Firedoglake or Google about the trial, so it looks like we're still waiting. No discussion of wasted tax dollars could be complete without mentioning what the Bush Administration are doing to our national security. Scarecrow at FDL provides a good roundup. According to the AP, we've reached 3,163 dead American servicemembers in Iraq.


One Fly said...

None of this worked our too good for us did it.

Cujo359 said...

I still think that chip-scale atomic clocks have possibilities, but none of the rest did, that's for sure.