Black holes, some of the most peculiar objects in the universe, pose a paradox for physicists. Two of our best theories give us two different—and seemingly contradictory—pictures of how these objects work. Many scientists, including myself, have been trying to reconcile these visions, not just to understand black holes themselves, but also to answer deeper questions, such as “What is spacetime?
Here is the problem: From the perspective of general relativity, black holes arise if the density of matter becomes too large and gravity collapses the material all the way toward its central point. When this happens, gravity is so strong in this region that nothing—even light—can escape.
While you're here, how about this:
Black holes caught in the act of swallowing stars | Science | AAAS
At the center of nearly every galaxy lies a monster, a giant black hole millions or even billions of times heavier than the Sun. Some, known as quasars or active galactic nuclei, shine brightly from across the universe as they continuously devour surrounding gas. But most are dormant, lurking invisibly for thousands of years—until a star passes too close and is ripped to shreds. That triggers a monthslong tidal disruption event (TDE), which can shine as brightly as a supernova.
Calculating Hawking radiation at the event horizon of a black hole
It is believed impossible to look beyond the event horizon of a black hole because nothing can escape, including particles and radiation. However, Stephen Hawking proved that black holes can "evaporate" by emitting various elementary particles. This means that over time, all the information absorbed by a black hole can disappear, which is contrary to fundamental ideas about information—it is believed that information cannot disappear without a trace.
One of the most promising approaches is the Einstein-dilaton-Gauss-Bonnet theory with dilaton—it applies quantum components as a correction to the Theory of General Relativity.
Unified Binary Stars Identified as the Bizarre Objects Seen Near the Supermassive Black Hole at
One object in the middle of the Milky Way galaxy (MWG) perplexed astronomers for quite some time. It is thought to be a hydrogen gas cloud on a collision course with a black hole.
The lead scientist, who is Andrea Ghez, professor of physics and astronomy at UCLA thinks that it can be identified. By all indications, G2 is a pair of binary stars that are revolving around the black hole but merged into a larger body. It gives off gas and dust as the gravitons of the blackhole affect the unified body of the two stars. As if quantumly entangles on a larger scale than mere particles.
Other things to check out:
Astronomers Have Mapped The Gas Swirls of a Wildly Fluctuating Black Hole
Black holes are cosmic objects of such fearsome density that even light cannot escape their extreme gravitational clutches. But just because they're invisible, doesn't mean we can't find ways to observe them.
This time, astronomers have mapped the contours of a supermassive vortex in the host galaxy IRAS 13224-3809 , found in the Centaurus constellation some 1 billion light-years from Earth.
To achieve this, researchers relied on the longest-ever observations of an accreting black hole by the European Space Agency's (ESA) XMM-Newton X-ray observatory.
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Take control of Mac audio with BlackHole virtual audio driver
BlackHole is a free, open-source tool to route audio anywhere on your Mac. You know how the audio from YouTube in Safari comes out the speakers or headphones of your Mac, and that's about it? Well, with BlackHole, you can intercept that audio. Then you can record it, redirect it to another app or do basically anything you like.
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Now, any audio you play on your Mac will go to BlackHole instead of out the speakers. Now, open up a recording app, like QuickTime Player, which comes built-in with your Mac. Open a new audio recording window, and in the pop-open menu, choose BlackHole 16ch as the "microphone." Hit record, and you're recording YouTube!
If the nearest star beyond the sun were a black hole, we might not be here - CNET
Black holes are among the most powerful, fascinating and terrifying objects in the universe, gobbling up everything that ventures near. One scientist has run the numbers on what might happen if there were a black hole just beyond our solar system, and it's not pretty.
"The planet, starting from the current heliocentric distance of the Earth, may even impact its star in about 2 to 3 million years," Iorio writes.
M87 is actually 53 million light-years away. The nearest known black hole — Sag A at the center of the Milky Way — is just under 26,000 light-years away. That's a much more comfortable buffer than the single parsec (3.26 light-years) used in Iorio's calculation, which would put the imagined black hole closer to us than Alpha Centauri, the nearest star beyond our sun.
Happening on Twitter
Opinion: Have we solved the black hole information paradox? The answer is maybe. And we may soon have a new underst… https://t.co/kbNM9hROt9 sciam (from New York City) Thu Jan 30 21:52:44 +0000 2020
Some people say that we should study to become climate scientists so that we can "solve the climate crisis". But th… https://t.co/2otMM2lVNo MikeHudema (from Unceded Squamish Territory) Sat Jan 25 12:22:43 +0000 2020
"We have to realize that this is not playing games… This is an urgent problem that has to be solved and, what's mor… https://t.co/1eKYywXoXt ClimateReality (from Washington, DC) Mon Jan 27 15:55:02 +0000 2020
"Moral distress is usually defined as the reaction of any sane human if they feel responsible, but disempowered. In… https://t.co/qn4eD3QCtJ bmj_latest (from London Beijing Delhi New York) Tue Jan 28 08:00:43 +0000 2020
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