Mitra's book discusses critical issues on astrophysics and general relativity in layman's language, as also shares anecdotes on scientific intolerance, writes Dr Kanika Das
As a mathematical physicist and researcher in general relativity and cosmology, initially I was bit annoyed with the very title of this book, and I thought that Mitra was bragging, there could never be anything like a "fall" of the black hole paradigm.
I was not aware that way back in 1969, the noted French relativist Luis Bel had shown that a true mathematical black hole, assumed to be a sphere, should actually behave like a point implying that its mass-energy is E=Mc2 =0. If this is true, the black hole paradigm certainly fell right in 1969 even though we mathematical physicists cannot accept such a tragic climb down.
Other things to check out:
Scientists capture a stunning black hole outburst
Throughout 2018 and 2019, a group of astronomers stared at a black hole some 10,000 light years away from Earth. This black hole, part of a binary system dubbed MAXI J1820+070 and situated within the Milky Way, is about 8 times the mass of the Sun. It's companion star, meanwhile, measures about half the mass of the Sun.
The reason for their interest was what alerted them to the binary system's existence in the first place: A sudden blast of light in July of 2018 which caught the astronomers by surprise. They caught a startling glimpse of two hot, gas jets , bursting forth from the black hole at 80 percent the speed of light . The jets' sheer energy created a hypnotic cosmic flare, and further fueled our fascination with these strange cosmic bodies.
Vaccine injury claims could face bureaucratic 'black hole' | The Sumter Item
Lost in the U.S. launch of the coronavirus vaccine is a fact most don't know when they roll up their sleeves: In rare cases of serious illness from the shots, the injured are blocked from suing and steered instead to an obscure federal bureaucracy with a record of seldom paying claims.
George Washington University law professor Peter Meyers has followed the program for years and bluntly calls it a "black hole," obtaining federal documents this summer showing it has paid fewer than 1 in 10 claims in its 15-year history.
Black Holes Discharge the Energy in Their Powerful Plasma Jets Much Farther Away Than Thought
In this artist’s rendering courtesy of NASA, the remnants of a star torn apart by a black hole form a disk around the black hole’s center, while jets eject from either side. The jets can travel at nearly the speed of light, and they discharge their high energy along the way. New research from UMBC in Nature Communications shows that the energy dissipation happens much farther away from the black hole’s center than previously thought.
The supermassive black holes at the centers of galaxies are the most massive objects in the universe. They range from about 1 million to upwards of 10 billion times the mass of the Sun. Some of these black holes also blast out gigantic, super-heated jets of plasma at nearly the speed of light . The primary way that the jets discharge this powerful motion energy is by converting it into extremely high-energy gamma rays. However, UMBC physics Ph.D.
While you're here, how about this:
The Milky Way black hole emitted two huge X-ray bubbles; Read details
A team of astronomers led by Andrea Merloni at the Max Planck Institute for Extraterrestrial Physics in Germany recently found out that a black hole in the milky way galaxy released two plasma bubbles. Their findings and research were published in Nature journal. Read on to know more details:
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According to New Scientist , the team used the Erosita x-Ray telescope situated at the Spektr-RG space observatory to find about this cosmic event in space. They found out that the x-ray bubbles were extending below and above the milky way galaxy. Such bubbles emit a huge amount of X-Rays throughout the galaxy.
Black Holes Are Finally Trending - Scientific American
With black holes, what you see is not what you get. The ring of light visible around a black hole’s silhouette originates from a radius of about 5GM/c 2 , where G is Newton’s constant, M is the black hole mass and c is the speed of light. This ring is larger than the event horizon of a nonspinning black hole by a factor of 2.5—or up to five with the addition of spin.
In 1939, Albert Einstein wrote a paper in Annals of Mathematics doubting that black holes exist in nature. Now, black holes are in vogue—so much so that the 2020 Nobel prize in physics was awarded to three scientists who have studied them . This gave me reason to celebrate, as the founding director of Harvard’s Black Hole Initiative , which brings together astronomers, physicists, mathematicians and philosophers, all dedicated to research on black holes.
Astronomers spot the biggest, strangest black hole collision ever found
Artist's impression of binary black holes about to collide. It is not known if there were any electromagnetic emissions associated with GW190521.
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More than seven billion years ago, two immense black holes circled each other until they collided and merged, a cataclysm so intense that it sent ripples soaring through the fabric of space-time. In the early morning hours of May 21, 2019, Earth trembled from the vibrations sent off by this distant carnage, cluing in astronomers to the biggest cosmic bang they'd ever detected—and one that defies theoretical expectation.
What happens at the center of a black hole? | Space
The singularity at the center of a black hole is the ultimate no man's land: a place where matter is compressed down to an infinitely tiny point, and all conceptions of time and space completely break down. And it doesn't really exist. Something has to replace the singularity, but we're not exactly sure what.
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It could be that deep inside a black hole, matter doesn't get squished down to an infinitely tiny point. Instead, there could be a smallest possible configuration of matter, the tiniest possible pocket of volume.
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