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Submission + - First Nuclear Clocks Start Ticking in Vienna and Beijing (phys.org)

Submitted by necro81
necro81 writes: Two groups, one in Vienna and one in Beijing, have successfully demonstrated the world's first nuclear clocks. Standard atomic clocks, like the caesium clocks that define the second, operate by observing the transition of electrons between different orbits about the nucleus. The resulting radiation is usually in the microwave range, and can produce clocks accurate to one second in 100 billion years.

Nuclear clocks go a step further, and probe energy transitions within the nucleus itself. Nuclei can arrange their protons and neutrons into different configurations, called isomers. The isomer with the lowest energy is the one usually found; higher-energy ones are only metastable and decay quickly. Usually it takes serious energy — x-rays and gamma rays — to excite a nucleus into a higher-energy arrangement. It so happens that thorium-229 can be excited using UV light with a wavelength of 148 nm — just within the capabilities of some exotic lasers.

It's still been quite a challenge. For one thing, Th-229 is not found in nature; it must be extracted from the decay chain of uranium-235. The Beijing team used just a microgram mixed in a crystal of calcium fluoride.

Although these prototype nuclear clocks are not yet more accurate than existing atomic clocks (one second in millions, rather than billions, of years), they show the way towards what may be possible. Because the energy transition is in the nucleus, rather than the electron cloud, it is less susceptible to outside disturbances like magnetic fields. And the fundamental frequency is much higher (five orders of magnitude), which should yield more precise timing. This development could lead to smaller and more reliable time standards across the world (and solar system).

Submission + - Wisconsin U–Madison Prof Francis Halzen named 2026 Nobel laureate in physi (wisc.edu)

Submitted by schwit1
schwit1 writes: Halzen is the principal investigator of the NSF IceCube Neutrino Observatory, the world’s largest — and perhaps strangest — telescope. The U.S. National Science Foundation-funded observatory is operated by an international collaboration of scientists led by the Wisconsin IceCube Particle Astrophysics Center based at UW–Madison.

Embedded in a cubic kilometer of Antarctic ice, IceCube uses thousands of light sensors to survey the universe for neutrinos, nearly massless particles that rarely interact with other matter. Neutrinos provide information about the workings of black holes, galaxies and other objects in the cosmos.

“IceCube is like no other telescope in the world,” says UW–Madison interim Chancellor Eric M. Wilcots. “And there is no other scientist quite like Francis Halzen, whose idea to create a neutrino detector under almost a mile of ice has led to a remarkable multinational and multi-institutional scientific collaboration and a fundamental shift in how we think about the universe.”

Comment Re:Corpospeak... (Score 2) 26

Translation: We are looking at our options on how to extract as much money as possible from the users of this software.

Or: We eliminated the positions necessary to merge the changes coming from the outside, and we will support the customers in house, if there are any paying customers at all. After that, we will close the project for good.

Comment Re:If they are thermally efficient enough (Score 0) 122

by Sique (#66361188) Attached to: Google Tests AI Data Center In Space
While in general, I agree with your sentiment, you mentioning the Dunning-Kruger effect is not appropriate here. Dunning and Kruger (1999) does not claim incompetent people would consider themselves above the experts. It's just that incompetent people do no consider themselves as incompetent as they really are, and competent people don't understand how far above the laymen their knowledge is. But both would agree, that the expert knows more about the topic than the layman, and both would sort themselves in the right categories.

You could consider the effect of Dunning and Kruger (1999) as a "mental regression to the mean".

Comment Is this legal? (Score 2) 116

by belmolis (#66360282) Attached to: Used Processor Leads To Game Ban
I wonder whether this is legal. Riot has the right to ban players who cheat, but maybe not the right to misidentify them based on the hardware they are using. In this case, since the game is free, there may be no contract of which this is a breach. In the case of a paid game, it seems that it would be a breach of contract.

Comment Re:Do you actually use them day today though? (Score 1) 105

It's normal that any OS will have close to 0 free memory! This is the expected behavior..

Describe "0 free memory". When I say it is 100%, I am literally looking at Outlook, Windows services, and Excel taking almost 16GB by themselves. This is not cached memory model of the Linux and MacOS where free RAM is reserved for caching. At 16GB, the "cached memory" on my Windows machine is disk swap as I can see the disk activity.

See my other post just above.

I am not searching through this forum just because you can't be bothered to retype or paste a link. Also I have to read your mind to determine which of your posts apply? That's a no.

Comment Re:8 GB of RAM (Score 1) 105

There are lots of things that could be removed from Windows that are unnecessary; however, MS makes it more difficult with each new update and patch. Removing them for the performance is such a hassle that few do it. For example, I don’t have an Xbox but MS deems it that I must have Xbox Gaming installed with each major update. It used to be that you could uninstall it. Now you can remove it but it really is not uninstalled as components still exist; for example all the modules that connect to the Xbox gaming servers still are present.

There are all sorts of service running that do not to be. I don’t have a touch screen yet all components for it cannot be removed. My machine is a desktop not a laptop yet airplane mode exists and cannot be removed. I know because one day it was triggered somehow and I was off the Internet until I rebooted and reset everything.

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