Jon Baer

Neutrinos are electrically neutral leptons, and interact very rarely with matter. When they do react with the molecules of water in the ice, they can create charged leptons (electrons, muons, or taus). These charged leptons can, if they are energetic enough, emit Cherenkov radiation. This happens when the charged particle travels through the ice faster than the speed of light in the ice, similar to the bow shock of a boat traveling faster than the waves it crosses. This light can then be detected by photomultiplier tubes within the digital optical modules making up IceCube.

Shoichi Sakata (坂田 昌一 Sakata Shōichi^?, 18 January 1911, near Hiroshima - 16 October 1970) was a Japaneseacademic and physicist who was internationally known for theoretical work on the structure of the atom.^[1] He proposed the Sakata model, which was an early precursor to the quark model.

Back of the Envelope Problems

Mobile is going to crush Facebook. The logic for Facebook’s price decline is that they have a problem in mobile. They can’t offer all the games they can in a browser. They can’t offer the same ads or branding opportunities. All true.

And the answer is: there is much more electromagnetic energy in your eye at any one moment from the infrared radiation you’re emitting yourself, than the pittance of visible light you get from the outside world. Between 100,000 and a million times as much. Which raises a question we may never have thought to ask: why does it get dark when we close our eyes? The amount of electromagnetic radiation hitting our retinas hardly changes!

The AWS VM Import service gives you the ability to import virtual machines in a variety of formats into Amazon EC2, allowing you to easily migrate from your on-premises virtualization infrastructure to the AWS Cloud. Today we are adding the next element to this service. You now have the ability to export previously imported EC2 instances back to your on-premises environment.

Up till now, most researchers have tried getting robots to move as one by programming them to communicate with one another using various kinds of networks. The drawback is that networks tend to have latency issues, which can cause a robot to get out of synch. Other researchers have tried to preprogram the same routine into each robot and then get them to start at the same time. The problem with that of course, is if one of the robots encounters a problem, such as falling, it won’t know how to catch up to the others. To get such around such issues Bechon and Slotine looked at how nature has developed a means to handle the problem.

If you supply a post-receive URL, GitHub will POST to that URL when someone uses git push on that repository.

The trapped rainbow could be utilised in tiny biosensors to identify biological materials based on the amount of light they absorb and then subsequently emit, which is known as fluorescence spectroscopy. Slowed-down light has a stronger interaction with molecules than light travelling at normal speeds, so it enables a more detailed analysis.

Solman noted that as far back as the Roman empire, people had worried about being displaced by machines. Emperor Vespasian, who built the Coliseum, refused to use labor-saving technology to move heavy columns. In more recent times, thinkers have worried that technological progression and increasing automation will only benefit the highly-educated and wealthy, leaving everyone behind.

Cherenkov radiation (also spelled Čerenkov) is electromagnetic radiation emitted when a charged particle(such as an electron) passes through a dielectric medium at a speed greater than the phase velocity of light in that medium. The charged particles polarize the molecules of that medium, which then turn back rapidly to their ground state, emitting radiation in the process. The characteristic blue glow of nuclear reactors is due to Cherenkov radiation. Its existence was predicted by the English polymath Oliver Heaviside in papers published in 1888–1889, but it is named after Russian scientist Pavel Alekseyevich Cherenkov, the 1958 Nobel Prizewinner who was the first to characterise it rigorously.^[1]

“Ring-imaging” detectors take advantage of the Cherenkov light produced by charged particles moving through a medium faster than the speed of light in that medium. In these detectors, a large volume of clear material (e.g., water or ice) is surrounded by light-sensitive photomultiplier tubes. A charged lepton produced with sufficient energy typically travels faster than the speed of light in the detector medium (though slower than the speed of light in a vacuum). This generates an “optical shockwave” known as Cherenkov radiation which can be detected by the photomultiplier tubes. The result is a characteristic ring-like pattern of activity on the array of photomultiplier tubes. This pattern can be used to infer direction, energy, and (sometimes) flavor information about the incident neutrino.

The Daya Bay Reactor Neutrino Experiment is a China-based multinational particle physics project studying neutrinos. The multinational collaboration includes researchers from China, the United States, Taiwan, and the Czech Republic. The US side of the project is funded by the US Department of Energy’s Office of High Energy Physics.

The Homestake experiment (sometimes referred to as the Davis experiment) was an experiment headed by astrophysicists Raymond Davis, Jr. and John N. Bahcall in the late 1960s. Its purpose was to collect and count neutrinos emitted by nuclear fusion taking place in the Sun. Bahcall did the theoretical calculations and Davis designed the experiment. After Bahcall calculated the rate at which the detector should capture neutrinos, Davis’s experiment turned up only one third of this figure. The experiment was the first to successfully detect and count solar neutrinos, and the discrepancy in results essentially created thesolar neutrino problem. The experiment operated continuously from 1970 until 1994. The University of Pennsylvania took it over in 1984. The discrepancy between the predicted and measured rates of neutrino detection was later found to be due to neutrino “flavor” oscillations.