Archive for the ‘physics’ category

Feb 14, 2019

New Map of Dark Matter Spanning 10 Million Galaxies Hints at a Flaw in Our Physics

Posted by in categories: cosmology, physics

An invisible force is having an effect on our Universe. We can’t see it, and we can’t detect it — but we can observe how it interacts gravitationally with the things we can see and detect, such as light.

Now an international team of astronomers has used one of the world’s most powerful telescopes to analyse that effect across 10 million galaxies in the context of Einstein’s general relativity. The result? The most comprehensive map of dark matter across the history of the Universe to date.

It has yet to complete peer-review, but the map has suggested something unexpected — that dark matter structures might be evolving more slowly than previously predicted.

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Feb 13, 2019

Running an LED in reverse could cool future computers

Posted by in categories: computing, engineering, physics

In a finding that runs counter to a common assumption in physics, researchers at the University of Michigan ran a light emitting diode (LED) with electrodes reversed in order to cool another device mere nanometers away.

The approach could lead to new solid-state technology for future microprocessors, which will have so many transistors packed into a small space that current methods can’t remove heat quickly enough.

“We have demonstrated a second method for using photons to cool devices,” said Pramod Reddy, who co-led the work with Edgar Meyhofer, both professors of mechanical engineering.

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Feb 13, 2019

New Map of Dark Matter Breaks Scientists’ Understanding of Physics

Posted by in categories: cosmology, physics

What they found was surprising. The new map, published on the preprint server arXiv, suggests that the huge structure of dark matter in the universe formed more slowly that previously believed — results that “appear to challenge current understanding of the fundamental laws of physics,” according to the press release.

Road Ahead

But before physicists throw out the rulebook, Hikage cautioned that the new map needs to be corroborated.

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Feb 10, 2019

Physicists Found a Brand-New Kind of Magnet Hiding in a Uranium Compound

Posted by in category: physics

This strange type of magnetism can form rapidly — and disappear just as quickly.

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Feb 8, 2019

Big Bang May Have Created a Mirror Universe Where Time Runs Backwards

Posted by in categories: cosmology, physics

Why does time seem to move forward? It’s a riddle that’s puzzled physicists for well over a century, and they’ve come up with numerous theories to explain time’s arrow. The latest, though, suggests that while time moves forward in our universe, it may run backwards in another, mirror universe that was created on the “other side” of the Big Bang.

Two leading theories propose to explain the direction of time by way of the relatively uniform conditions of the Big Bang. At the very start, what is now the universe was homogeneously hot, so much so that matter didn’t really exist. It was all just a superheated soup. But as the universe expanded and cooled, stars, galaxies, planets, and other celestial bodies formed, birthing the universe’s irregular structure and raising its entropy.

One theory, proposed in 2004 by Sean Carroll, now a professor at Caltech, and Jennifer Chen, then his graduate student, says that time moves forward because of the contrast in entropy between then and now, with an emphasis on the fact that the future universe will so much more disordered than the past. That movement toward high entropy gives time its direction.

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Feb 7, 2019

The Future Circular Collider: Can it Unlock Mysteries of the Universe?

Posted by in categories: energy, physics, space

In the early 1990s, I was lucky enough to get some time on a 60 MeV linear accelerator as part of an undergraduate lab course. Having had this experience, I can feel for the scientists at CERN who have had to make do with their current 13 TeV accelerator, which only manages energies some 200,000 times larger. So, I read with great interest when they announced the publication of the initial design concept for the Future Circular Collider (FCC), which promises collisions nearly an order of magnitude more energetic. The plan, which has been in the works since 2014, includes three proposals for accelerators which would succeed CERN’s current big iron, the LHC.

Want to know what’s on the horizon in high-energy physics?

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Feb 6, 2019

Are Earth’s Magnetic Poles About To Flip, And What Will Happen When They Do?

Posted by in category: physics

There’s a renewed interest right now in Earth’s magnetic poles – specifically, whether or not they’re about to flip, and what may happen. The consequences of this seemingly rapid geomagnetic backflip may sound a little ominous, but don’t worry: we’re not sure when the next reversal will happen, and even when it does, the risks aren’t likely to be as scary as you may think.

Let’s start with the basics.

As Earth’s liquid, iron-rich outer core gradually cools, it sloshes around through colossal convection currents, which are also somewhat warped by Earth’s own rotation. Thanks to a quirk of physics known as the dynamo theory, this generates a powerful magnetic field, with a north and south end.

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Feb 6, 2019

Plasma-based system provides radical new path for water purification

Posted by in categories: engineering, physics

Many of today’s methods of purifying water rely on filters and chemicals that need regular replenishing or maintenance. Millions of people, however, live in areas with limited access to such materials, leading the research community to explore new options of purifying water in using plasmas. Many plasma-based approaches are expensive, but a new class of plasma devices may change that.

Researchers at the University of Alabama in Huntsville have been studying a new type of plasma generator for water purification. The new generator pulses voltage signals to ionize gas at atmospheric pressure and produce many useful byproducts, including , which cause a cascade of reactions that lead to purer water samples.

“We’re finding ways to speed up the purification process,” said Ryan Gott, a doctoral candidate in aerospace engineering at UAH who will present the research next week at the American Physical Society 71st Annual Gaseous Electronics Conference and the 60th Annual meeting of the APS Division of Plasma Physics, which will take place Nov. 5–9 at the Oregon Convention Center in Portland.

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Feb 6, 2019

Experimental plasma generator offers path forward for better use of landfill gas as energy

Posted by in categories: energy, physics

Researchers at the University of South Carolina in Columbia have demonstrated an experimental plasma device capable of cleaning gas samples of D4, one of the most common siloxanes. Drawing on a technique for creating plasma called dielectric barrier discharge, the group was able to significantly reduce the amount of D4 samples after treating it with a helium-based plasma.

The findings point to a new potential solution for accommodating landfill gas rich in siloxanes. They will be presented at the American Physical Society 71st Annual Gaseous Electronics Conference and 60th Annual meeting of the APS Division of Plasma Physics, which takes place Nov. 5–9 at the Oregon Convention Center in Portland.

“This is the first time dielectric barrier discharge has been used to remove volatile organic silicate compounds,” said Malik Tahiyat, one of the researchers involved with the study. “In our case, there’s no wait for removing it or material that has to be thrown out after a certain amount of time.”

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Feb 3, 2019

The Search for New Physics & CERN’s FCC Future Circular Collider

Posted by in categories: astronomy, engineering, environmental, ethics, existential risks, particle physics, physics, quantum physics, science

It is a few years since I posted here on Lifeboat Foundation blogs, but with the news breaking recently of CERN’s plans to build the FCC [1], a new high energy collider to dwarf the groundbreaking engineering triumph that is the LHC, I feel obliged to write a few words.

The goal of the FCC is to greatly push the energy and intensity frontiers of particle colliders, with the aim of reaching collision energies of 100 TeV, in the search for new physics [2]. Below linked is a technical note I wrote & distributed last year on 100 TeV collisions (at the time referencing the proposed China supercollider [3][4]), highlighting the weakness of the White Dwarf safety argument at these energy levels, and a call for a more detailed study of the Neutron star safety argument, if to be relied on as a solitary astrophysical assurance. The argument applies equally to the FCC of course:

The Next Great Supercollider — Beyond the LHC :

The LSAG, and others including myself, have already written on the topic of astrophysical assurances at length before. The impact of CR on Neutron stars is the most compelling of those assurances with respect to new higher energy colliders (other analogies such as White Dwarf capture based assurances don’t hold up quite as well at higher energy levels). CERN will undoubtedly publish a new paper on such astrophysical assurances as part of the FCC development process, though would one anticipate it sooner rather than later, to lay to rest concerns of outsider-debate incubating to a larger audience?

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