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Extreme black holes may have "hair," find scientists
Researchers discover black holes that violate the uniqueness theorem and have "gravitational hair."
- Scientists discover that some extreme black holes may violate the "no hair" theorem.
- These black holes feature properties outside of the three classical black hole traits of mass, spin, and charge.
- The researchers ran sophisticated simulations to discover these space oddities.
Black holes are wonderfully weird, sparking the imagination with the many mysteries surrounding their formation and functions in our universe. Now scientists found a new kind of extreme black hole, one that breaks the so-called "ho hair" theorem. In other words, this black hole has "hair."
The idea of the "no hair" or "black hole uniqueness" theorem was encapsulated by the American theoretical physicist John Wheeler who claimed: "Black holes have no hair." What he meant is that black hole solutions to Einstein's field equations of general relativity can be completely characterized by only three physical quantities: mass, spin, and charge. There aren't supposed to be any other "hairy" traits that can make one black hole different from another. Black holes with the same mass, spin, and charge should be identical, explains the press release from Theiss Research, which was behind the new discovery.
The team involved Dr. Lior Burko of Theiss Research, Professor Gaurav Khanna of the University of Massachusetts Dartmouth and the University of Rhode Island, as well as his former student Dr. Subir Sabharwal.
They found there's an extremal black hole that may violate the "no hair" theorem. This type of black hole is "saturated" with the maximum charge or spin it can potentially carry. The researchers discovered that there exists a conserved quantity or property that can be constructed from the spacetime curvature at such a black hole's horizon. It may be measurable from Earth by gravitational wave observatories like LIGO and LISA. Since this property is dependent on how the black hole was formed, it breaks the black hole uniqueness theorem and is considered "gravitational hair."
"This new result is surprising because the black hole uniqueness theorems are well established, and in particular their extension to extreme black holes," shared Dr. Burko. "There has to be an assumption of the theorems that is not satisfied, to explain how the theorems do not apply in this case."
The mind-blowing science of black holes | Michio Kaku, Bill Nye, Michelle Thaller & more
For their findings, the researchers employed elaborate numerical simulations running on dozens of the top Nvidia graphics-processing-units (GPUs) that had over 5,000 cores each, working in parallel. "Each of these GPUs can perform as many as 7 trillion calculations per second; however, even with such computational capacity the simulations look [sic] many weeks to complete," shared Khanna.
Another type of black hole "hair" was proposed by Stephen Hawking who predicted that quantum particles would leak out of black holes, in a phenomenon dubbed "Hawking radiation." This claim was possibly proven correct by a 2020 study that found evidence of "quantum fuzz" and gravitational wave "echoes" beyond black hole event horizons.
Check out the new study published in Physical Review D.
- Black holes are fuzzy, new study suggests - Big Think ›
- Are Tiny Black Holes Created During the Big Bang Floating Around ... ›
This storm rained electrons, shifted energy from the sun's rays to the magnetosphere, and went unnoticed for a long time.
- An international team of scientists has confirmed the existence of a "space hurricane" seven years ago.
- The storm formed in the magnetosphere above the North magnetic pole.
- The storm posed to risk to life on Earth, though it might have interfered with some electronics.
What do you call that kind of storm when it forms over the Arctic ocean?<iframe width="730" height="430" src="https://www.youtube.com/embed/8GqnzBJkWcw" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe><p> Many objects in space, like Earth, the Sun, most of the planets, and even some large moons, have magnetic fields. The area around these objects which is affected by these fields is known as the magnetosphere.</p><p>For us Earthlings, the magnetosphere is what protects us from the most intense cosmic radiation and keeps the solar wind from affecting our atmosphere. When charged particles interact with it, we see the aurora. Its fluctuations lead to changes in what is known as "space weather," which can impact electronics. </p><p>This "space hurricane," as the scientists are calling it, was formed by the interactions between Earth's magnetosphere and the <a href="https://en.wikipedia.org/wiki/Interplanetary_magnetic_field" target="_blank" rel="noopener noreferrer">interplanetary magnetic field,</a> the part of the sun's magnetosphere that goes out into the solar system. It took on the familiar shape of a cyclone as it followed magnetic fields. For example, the study's authors note that the numerous arms traced out the "footprints of the reconnected magnetic field lines." It rotated counter-clockwise with a speed of nearly 7,000 feet per second. The eye, of course, was still and <a href="https://www.sciencealert.com/for-the-first-time-a-plasma-hurricane-has-been-detected-in-space" target="_blank" rel="noopener noreferrer">calm</a>.</p><p>The storm, which was invisible to the naked eye, rained electrons and shifted energy from space into the ionosphere. It seems as though such a thing can only form under calm situations when large amounts of energy are moving between the solar wind and the upper <a href="https://www.reading.ac.uk/news-and-events/releases/PR854520.aspx" target="_blank">atmosphere</a>. These conditions were modeled by the scientists using 3-D <a href="https://www.nature.com/articles/s41467-021-21459-y#Sec10" target="_blank">imaging</a>.<br><br>Co-author Larry Lyons of UCLA explained the process of putting the data together to form the models to <a href="https://www.nbcnews.com/science/space/space-hurricane-rained-electrons-observed-first-time-rcna328" target="_blank">NBC</a>:<br><br>"We had various instruments measuring various things at different times, so it wasn't like we took a big picture and could see it. The really fun thing about this type of work is that we had to piece together bits of information and put together the whole picture."<br><br>He further mentioned that these findings were completely unexpected and that nobody that even theorized a thing like this could exist. <br></p><p>While this storm wasn't a threat to any life on Earth, a storm like this could have noticeable effects on space weather. This study suggests that this could have several effects, including "increased satellite drag, disturbances in High Frequency (HF) radio communications, and increased errors in over-the-horizon radar location, satellite navigation, and communication systems."</p><p>The authors <a href="https://www.nature.com/articles/s41467-021-21459-y#Sec8" target="_blank" rel="noopener noreferrer">speculate</a> that these "space hurricanes" could also exist in the magnetospheres of other planets.</p><p>Lead author Professor Qing-He Zhang of Shandong University discussed how these findings will influence our understanding of the magnetosphere and its changes with <a href="https://www.eurekalert.org/pub_releases/2021-03/uor-sho030221.php" target="_blank" rel="noopener noreferrer">EurekaAlert</a>:</p><p>"This study suggests that there are still existing local intense geomagnetic disturbance and energy depositions which is comparable to that during super storms. This will update our understanding of the solar wind-magnetosphere-ionosphere coupling process under extremely quiet geomagnetic conditions."</p>
Research reveals a new evolutionary feature that separates humans from other primates.
- Researchers find a new feature of human evolution.
- Humans have evolved to use less water per day than other primates.
- The nose is one of the factors that allows humans to be water efficient.
A model of water turnover for humans and chimpanzees who have similar fat free mass and body water pools.
Credit: Current Biology
Being skeptical isn't just about being contrarian. It's about asking the right questions of ourselves and others to gain understanding.
- It's not always easy to tell the difference between objective truth and what we believe to be true. Separating facts from opinions, according to skeptic Michael Shermer, theoretical physicist Lawrence Krauss, and others, requires research, self-reflection, and time.
- Recognizing your own biases and those of others, avoiding echo chambers, actively seeking out opposing voices, and asking smart, testable questions are a few of the ways that skepticism can be a useful tool for learning and growth.
- As Derren Brown points out, being "skeptical of skepticism" can also lead to interesting revelations and teach us new things about ourselves and our psychology.