http://www.livescience.com/58171-time-c ... e-lab.html
By Tia Ghose, Senior Writer |
Editor's Note: This article was updated on March 9 at 11:20 a.m. E.T.
A bizarre new state of matter known as a time crystal seems to suspend the laws of thermodynamics almost indefinitely, two new experiments suggest.
The time crystal is essentially a collection of atoms or ions that are far apart but still interacting with each other. This form of matter keeps "ticking" indefinitely at a certain frequency, without heating up or creating entropy, the natural state of disorder that always increases in the universe. Time crystals work because of quantum effects, or the bizarre rules describing the menagerie of tiny subatomic particles.
The newly created matter joins a host of other exotic states of matter, such as superconductors, quantum-spin liquids and superfluids.
"We have found a new phase of matter," said study co-author Soonwon Choi, a theoretical physics graduate student at Harvard University. "It's something moving in time while still stable." [The 18 Biggest Unsolved Mysteries in Physics]https://astronomynow.com/2017/03/14/sta ... lack-hole/https://astronomynow.com/2017/03/09/hub ... -big-meal/https://phys.org/news/2017-04-capture-i ... axies.htmlhttps://phys.org/news/2017-04-singulari ... verse.html
A team of scientists at the Tata Institute of Fundamental Research (TIFR), Mumbai, India, have found new ways to detect a bare or naked singularity, the most extreme object in the universe.
When the fuel of a very massive star is spent, it collapses due to its own gravitational pull and eventually becomes a very small region of arbitrarily high matter density, that is a 'Singularity', where the usual laws of physics may breakdown. If this singularity is hidden within an event horizon, which is an invisible closed surface from which nothing, not even light, can escape, then we call this object a black hole. In such a case, we cannot see the singularity and we do not need to bother about its effects. But what if the event horizon does not form? In fact, Einstein's theory of general relativity does predict such a possibility when massive stars collapse at the end of their life-cycles. In this case, we are left with the tantalizing option of observing a naked singularity.https://phys.org/news/2017-04-naked-mol ... xygen.html
Deprived of oxygen, naked mole-rats can survive by metabolizing fructose just as plants do, researchers report this week in the journal Science.
Understanding how the animals do this could lead to treatments for patients suffering crises of oxygen deprivation, as in heart attacks and strokes.
"This is just the latest remarkable discovery about the naked mole-rat—a cold-blooded mammal that lives decades longer than other rodents, rarely gets cancer, and doesn't feel many types of pain," says Thomas Park, professor of biological sciences at the University of Illinois at Chicago, who led an international team of researchers from UIC, the Max Delbrück Institute in Berlin and the University of Pretoria in South Africa on the study.
In humans, laboratory mice, and all other known mammals, when brain cells are starved of oxygen they run out of energy and begin to die.
But naked mole-rats have a backup: their brain cells start burning fructose, which produces energy anaerobically through a metabolic pathway that is only used by plants - or so scientists thought.
In the new study, the researchers exposed naked mole-rats to low oxygen conditions in the laboratory and found that they released large amounts of fructose into the bloodstream. The fructose, the scientists found, was transported into brain cells by molecular fructose pumps that in all other mammals are found only on cells of the intestine.
Read more at: https://phys.org/news/2017-04-naked-mol ... n.html#jCphttps://www.quantamagazine.org/20170418 ... -389607397
nor point of interest regarding the Spitler Burst.” The email subject line popped up on Shami Chatterjee’s computer screen just after 3 in the afternoon on Nov. 5, 2015.
When Chatterjee read the email, he first gasped in shock — and then sprinted out of his Cornell University office and down the corridor to tell a colleague. Twenty-eight minutes later, when he started to draft a reply, his inbox was already buzzing. The email thread grew and grew, with 56 messages from colleagues by midnight.
For nearly a decade, Chatterjee and other astrophysicists on the thread had been trying to understand the nature of short, superenergetic flashes of radio waves in space. These “fast radio bursts,” or FRBs, last just a few milliseconds, but they are the most luminous radio signals in the universe, powered by as much energy as 500 million suns. The first one was spotted in 2007 by the astronomer Duncan Lorimer, who together with one of his students stumbled upon the signal accidentally in old telescope data; at the time, few believed it. Skeptics suspected interference from mobile phones or microwave ovens. But more and more FRBs kept showing up — 26 have been counted so far, including the Spitler burst, detected by the astronomer Laura Spitler in data from 2012 — and scientists had to agree they were real.
The question was, what causes them? Researchers sketched dozens of models, employing the gamut of astrophysical mysteries — from flare stars in our own galaxy to exploding stars,mergers of charged black holes, white holes, evaporating black holes, oscillating primordial cosmic strings, and evenaliens sailing through the cosmos using extragalactic light sails. For scientists, the FRBs were as blinding as flash grenades in a dark forest; their power, brevity and unpredictability simply made it impossible to see the source of the light.
The email alerting Chatterjee and colleagues to a “minor point of interest” changed all that. Its sender was Paul Scholz, a graduate student at McGill University in Montreal and a collaborator of Chatterjee’s. He was performing astrophysical “due diligence,” sifting with the help of a supercomputer through all the telescope data that had been collected from the part of the sky where the Spitler burst originated, to see whether the source might send a second signal. According to Chatterjee, after two years of doing this and seeing nothing, expectations had dimmed, but “it was just part of a regular rotation; you put in a few minutes to look for it anyway just in case.”https://www.quantamagazine.org/20150514 ... eed-limit/
the night of October 15, 1991, the “Oh-My-God” particle streaked across the Utah sky.
A cosmic ray from space, it possessed 320 exa-electron volts (EeV) of energy, millions of times more than particles attain at the Large Hadron Collider, the most powerful accelerator ever built by humans. The particle was going so fast that in a yearlong race with light, it would have lost by mere thousandths of a hair. Its energy equaled that of a bowling ball dropped on a toe. But bowling balls contain as many atoms as there are stars. “Nobody ever thought you could concentrate so much energy into a single particle before,” saidDavid Kieda, an astrophysicist at the University of Utah.https://www.quantamagazine.org/20150310 ... lden-mean/
What struck John Learned about the blinking of KIC 5520878, a bluish-white star 16,000 light-years away, was how artificial it seemed.
Learned, a neutrino physicist at the University of Hawaii, Mānoa, has a pet theory that super-advanced alien civilizations might send messages by tickling stars with neutrino beams, eliciting Morse code-like pulses. “It’s the sort of thing tenured senior professors can get away with,” he said. The pulsations of KIC 5520878, recorded recently by NASA’s Kepler telescope, suggested that the star might be so employed.
A “variable” star, KIC 5520878 brightens and dims in a six-hour cycle, seesawing between cool-and-clear and hot-and-opaque. Overlaying this rhythm is a second, subtler variation of unknown origin; this frequency interplays with the first to make some of the star’s pulses brighter than others. In the fluctuations, Learned had identified interesting and, he thought, possibly intelligent sequences, such as prime numbers (which have been floated as a conceivable basis of extraterrestrial communication). He then found hints that the star’s pulses were chaotic.https://www.quantamagazine.org/20160927 ... gonfly-44/
Among the thousand-plus galaxies in the Coma cluster, a massive clump of matter some 300 million light-years away, is at least one — and maybe a few hundred — that shouldn’t exist.
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Dragonfly 44 is a dim galaxy, with one star for every hundred in our Milky Way. But it spans roughly as much space as the Milky Way. In addition, it’s heavy enough to rival our own galaxy in mass, according to results published in the Astrophysical Journal Lettersat the end of August. That odd combination is crucial: Dragonfly 44 is so dark, so fluffy, and so heavy that some astronomers believe it will either force a revision of our theories of galaxy formation or help us understand the properties of dark matter, the mysterious stuff that interacts with normal matter via gravity and not much else. Or both.https://astronomynow.com/2017/03/09/anc ... rst-stars/https://www.quantamagazine.org/20170411 ... nes-proof/
Imagine a set of many lines as in a dream. The lines intersect at a point and radiate outward. There’s something perfect about the way they’re spaced that you can’t quite put your finger on. You start counting them, but before you can finish you wake up with a question hanging on the fringe of your mind: Just how many were there?
For at least 70 years, mathematicians have been trying to answer a question like that one. The sets of lines they’re interested in share a basic feature: Any two lines from the set intersect to form the same angle. Such sets of lines are called “equiangular.” Mathematicians want to know just how big those sets can get as you move past the 3-D space of our everyday experience and into higher dimensions.
there's an intriguing connection between the gaps in different energy levels in atoms and the seemingly random gaps in prime numbers.https://www.quantamagazine.org/20170404 ... ypothesis/
It's imperfect but still an intriguing connection- sort of like Bode's "law" for the gaps between the orbits of planetary bodies in the solar system.https://www.quantamagazine.org/20170302 ... of-groups/
The patterns of class numbers is also intriguing as is Fermat's last theorem.https://www.quantamagazine.org/20170303 ... t-theorem/
Everything in mathematics- and the rest of science- is connected.