backtop


Print 68 comment(s) - last by masher2.. on Aug 3 at 12:37 PM

Redefining time

According to reports published in the Physical Review Letter, the National Institute of Standards Technology (NIST) published a paper indicating that it had discovered a new type of atomic clock based on mercury-ion. The report said that the new atomic clock is so accurate it's nearly 6 times more precise than the current cesium-based atomic clock.

The report said that the NIST currently operates a cesium-based atomic clock called the NIST-F1, which is accurate for roughly 70 million years. If operated continuously, the NIST-F1 would only be off by 1 second after 70 million years. The new mercury-ion atomic clock on the other hand will take 400 million years.

The new experimental clock measures the atomic resonance frequency of a mercury atom. The atom itself is electrically charged and kept in an extremely cold suspension. Using the new mercury-ion atomic clock, scientists at the NIST say that they will be able to conduct more precise experiments and further develop applications that rely on atomic-time accuracy such as GPS systems. Currently, the international standard that defines what one second is relies on cesium-based atomic clocks -- 9,192,631,770 radiation cycles of the change between two energy levels of a cesium atom. The NIST says that it will be five to ten years before we see mercury-ion clocks replace cesium ones.



Comments     Threshold


This article is over a month old, voting and posting comments is disabled

RE: .
By GhandiInstinct on 8/1/2006 12:40:30 PM , Rating: 2
Let me enlighten you my friend since you have been kind enough to attempt the same:

Countries with Nuclear Warheads as of 2004

United States
10,455

Russia
8,400

China
400

France
350

Israel
250

United Kingdom
200

India
65

Pakistan
40

North Korea
8

TOTAL
20,168

Surely 20,168 Nukes raining across Earth isn't enough to do anything ^_^


RE: .
By masher2 (blog) on 8/1/2006 12:57:07 PM , Rating: 3
> "Let me enlighten you my friend "

Nuclear proliferation is a subject I've studied extensively since my days in graduate school. Here's a chart of US nuclear stockpiles over the years. As you see, its been well over 30,000 weapons in the 1960s, down to less than a third of that today. Same for the Soviet Union.

http://www.nrdc.org/nuclear/nudb/dafig9.asp

The figures fail to show the status of those warheads as well. In the 1960s, the majority were not only active, but pretargeted and ready to launch on a moment's notice. Today, the vast majority of our arsenal is in essentially in a "warm standby" mode.

In the past 40 years, the number of nuclear-capable nations has increased. That certainly increases the risk of a small nuclear exchange, but the risk of "destroying ourselves" as you put it, has declined dramatically over the years.


"Google fired a shot heard 'round the world, and now a second American company has answered the call to defend the rights of the Chinese people." -- Rep. Christopher H. Smith (R-N.J.)











botimage
Copyright 2014 DailyTech LLC. - RSS Feed | Advertise | About Us | Ethics | FAQ | Terms, Conditions & Privacy Information | Kristopher Kubicki