БЛОГ

Archive for the ‘physics’ category: Page 10

Sep 2, 2019

The Feynman Lectures on Physics Vol. II Ch. 34: The Magnetism of Matter

Posted by in category: physics

Dear Reader.

There are several reasons you might be seeing this page. In order to read the online edition of The Feynman Lectures on Physics, javascript must be supported by your browser and enabled. If you have have visited this website previously it’s possible you may have a mixture of incompatible files (.js,.css, and.html) in your browser cache. If you use an ad blocker it may be preventing our pages from downloading necessary resources. So, please try the following: make sure javascript is enabled, clear your browser cache (at least of files from feynmanlectures.caltech.edu), turn off your browser extensions, and open this page:

Aug 30, 2019

Physicists Outline an Ambitious Plan to Simulate Black Holes With Holograms

Posted by in categories: cosmology, holograms, physics

Black holes are some of the most powerful and fascinating phenomena in our Universe, but due to their tendency to swallow up anything nearby, getting up close to them for some detailed analysis isn’t possible right now.

Instead, scientists have put forward a proposal for how we might be able to model these massive, complex objects in the lab — using holograms.

While experiments haven’t yet been carried out, the researchers have put forward a theoretical framework for a black hole hologram that would allow us to test some of the more mysterious and elusive properties of black holes — specifically what happens to the laws of physics beyond its event horizon.

Aug 28, 2019

To Hunt Gravitational Waves, Scientists Had to Create the Quietest Spot on Earth

Posted by in categories: physics, space, transportation

LIVINGSTON, La. — About a mile and a half from a building so big you can see it from space, every car on the road slows to a crawl. Drivers know to take the 10 mph (16 km/h) speed limit very seriously: That’s because the building houses a massive detector that’s hunting for celestial vibrations at the smallest scale ever attempted. Not surprisingly, it’s sensitive to all earthly vibrations around it, from the rumblings of a passing car to natural disasters on the other side of the globe.

As a result, scientists who work at one of the LIGO (Laser Interferometer Gravitational-Wave Observatory) detectors must go to extraordinary lengths to hunt down and remove all potential sources of noise — slowing down traffic around the detector, monitoring every tiny tremor in the ground, even suspending the equipment from a quadruple pendulum system that minimizes vibrations — all in the effort to create the most “silent” vibrational spot on Earth.

Aug 27, 2019

Physicists Just Released Step-by-Step Instructions for Building a Wormhole

Posted by in categories: cosmology, physics, space travel

I am going home :3.


Everybody wants a wormhole. I mean, who wants to bother traveling the long-and-slow routes throughout the universe, taking tens of thousands of years just to reach yet another boring star? Not when you can pop into the nearest wormhole opening, take a short stroll, and end up in some exotic far-flung corner of the universe.

There’s a small technical difficulty, though: Wormholes, which are bends in space-time so extreme that a shortcut tunnel forms, are catastrophically unstable. As in, as soon as you send a single photon down the hole, it collapses faster than the speed of light.

Aug 27, 2019

From crystals to glasses: a new unified theory for heat transport

Posted by in categories: energy, physics

Theoretical physicists from SISSA and the University of California at Davis have developed a new approach to heat transport in materials, which finally allows crystals, polycrystalline solids, alloys and glasses to be treated on the same solid footing. It opens the way to the numerical simulation of the thermal properties of a vast class of materials in important fields such as energy saving, conversion, scavenging, storage, heat dissipation, shielding and the planetary sciences, which have thus far dodged a proper computational treatment. The research has been published in Nature Communications.

Heat dissipates over time. In a sense, is the defining feature of the arrow of time. In spite of the foundational importance of heat transport, the father of its modern theory, Sir Rudolph Peierls, wrote in 1961, “It seems there is no problem in modern physics for which there are on record as many false starts, and as many theories which overlook some essential feature, as in the problem of the thermal conductivity of nonconducting crystals.”

A half-century has passed since, and heat transport is still one of the most elusive chapters of theoretical materials science. As a matter of fact, no unified approach has been able to treat crystals and (partially) disordered solids on equal footing, thus hindering the efforts of generations of materials scientists to simulate certain materials, or different states of the same material occurring in the same physical system or device with the same accuracy.

Aug 26, 2019

Simulation of eight million ‘mock universes’ sheds light on galaxy evolution

Posted by in categories: cosmology, evolution, physics

Physics World represents a key part of IOP Publishing’s mission to communicate world-class research and innovation to the widest possible audience. The website forms part of the Physics World portfolio, a collection of online, digital and print information services for the global scientific community.

Aug 26, 2019

Physicists’ study demonstrates silicon’s energy-harvesting power

Posted by in categories: energy, internet, physics

A University of Texas at Dallas physicist has teamed with Texas Instruments Inc. to design a better way for electronics to convert waste heat into reusable energy.

The collaborative project demonstrated that silicon’s ability to harvest energy from heat can be greatly increased while remaining mass-producible.

Dr. Mark Lee, professor and head of the Department of Physics in the School of Natural Sciences and Mathematics, is the corresponding author of a study published July 15 in Nature Electronics that describes the results. The findings could greatly influence how circuits are cooled in electronics, as well as provide a method of powering the sensors used in the growing “internet of things.”

Aug 25, 2019

Laser-produced uranium plasma evolves into more complex species

Posted by in categories: evolution, physics

When energy is added to uranium under pressure, it creates a shock wave, and even a tiny sample will be vaporized like a small explosion. By using smaller, controlled explosions, physicists can test on a microscale in a safe laboratory environment what could previously be tested only in larger, more dangerous experiments with bombs.

“In our case, it’s the laser depositing energy into a target, but you get the same formation and time-dependent evolution of plasma,” author Patrick Skrodzki said. “With these small-scale explosions in the lab, we can understand similar physics.”

In a recent experiment, scientists working with Skrodzki used a laser to ablate atomic uranium, stealing its electrons until it ionized and turned to plasma, all while recording as the plasma cooled, oxidized and formed species of more complex uranium. Their work puts uranium species and the reaction pathways between them onto a map of space and time to discover how many nanoseconds they take to form and at which part of the plasma’s evolution.

Aug 24, 2019

Physicists Have Built The World’s Smallest Engine, And It’s Seriously Tiny

Posted by in categories: nanotechnology, physics, transportation

It’s not like the one in your car, but a team of physicists at Trinity College Dublin have built what they claim is the world’s smallest engine. The engine is the size of a single calcium ion — about ten billion times smaller than an automobile engine.

Rather than powering your next road trip, the atomic engine could one day be used to lay the foundation for extraordinary, futuristic nanotechnologies.

Here’s how it works: the calcium ion holds an electrical charge, which makes it spin. This angular momentum is then used to convert heat from a laser beam into vibrations.

Aug 23, 2019

Star crust is 10 billion times stronger than steel

Posted by in categories: cosmology, physics

By Rachel Courtland

The crust of neutron stars is 10 billion times stronger than steel, according to new simulations. That makes the surface of these ultra-dense stars tough enough to support long-lived bulges that could produce gravitational waves detectable by experiments on Earth.

Neutron stars are the cores left behind when relatively massive stars explode in supernovae. They are incredibly dense, packing about as much mass as the sun into a sphere just 20 kilometres or so across, and some rotate hundreds of times per second.

Page 10 of 100First7891011121314Last