Astrophysicists have devised a way to use the shadow of a supermassive black hole, shown in a simulation here, to test and rule out novel theories of gravity.
Outwitting Albert Einstein just got even tougher. More than 100 years ago, the famous physicist published his explanation of gravity, known as general relativity (GR), which successfully explains everything from the orbits of planets to the bending of starlight. Still, some physicists have been trying to invent theories that can solve puzzles GR cannot—for example, by explaining away the need for invisible dark matter, whose gravity appears to bind the galaxies.
Were you following this:
Astronomers spy galaxies caught in the web of a voracious black hole | Science | AAAS
Astronomers staring out to the farthest reaches of the universe, and hence the deepest depths of time, have been puzzled to find supermassive black holes . How could such behemoths have had time to swallow up so much matter when the universe was so young? With new observations of one of these youthful giants—a black hole 1 billion times the mass of the Sun and less than 1 billion years old—astronomers now have a possible answer.
They found the black hole was connected to six nearby galaxies by filaments: feeding tubes for the monster in their midst. Assembling this family portrait (imagined above) took many observations—some lasting all night long—with some of the world's largest telescopes, including the European Southern Observatory's Very Large Telescope in Chile.
Physics Nobel honors discoveries about black holes | Science | AAAS
Two of the three winners of the Nobel Prize in Physics helped discover supermassive black holes, containing millions or even billions of solar masses.
The Nobel Prize in Physics this year honors pioneering studies about the nature of black holes, including the discovery of the gigantic one lurking in the heart of our Milky Way Galaxy.
Half of the prize goes to Roger Penrose, a mathematician at the University of Oxford, for his work in the 1960s on the formation and stability of black holes. The other half is shared by two astronomers: Reinhard Genzel of the Max Planck Institute for Extraterrestrial Physics and Andrea Ghez of the University of California, Los Angeles.
First photo of a black hole supports Einstein's theory of relativity - CNN
(CNN) The first image of a black hole , captured in 2019, has revealed more support for Albert Einstein's theory of general relativity. The new finding has suggested his theory is now 500 times harder to beat.
Not to change the topic here:
What we thought was a black hole is actually something unexpected
Black holes are elusive enough, but what if you think you've found one and it ends up being something even weirder ?
Earlier this year, astronomers had thought that the black hole lurking closest to Earth had finally been found in its cosmic lair. It was supposedly the mystery object in the star system HR 6819 . The scientists who first tried to figure out what this thing really was concluded they were looking at a triple star system where one star was supposedly not moving and the other was at the mercy of an immense but invisible force—what they thought was a black hole.
Journey into a black hole: part 1 – podcast | Science | The Guardian
They are among the most enigmatic phenomena in the universe, confounding physicists and mathematicians. Black holes pull in the matter surrounding them and anything that enters can never escape. Yet they contain nothing at all. Guided by the physicist and author of Black Hole Survival Guide, Janna Levin, Madeleine Finlay takes Science Weekly on an interstellar voyage to visit one of these incredible astrophysical objects.
In the first of two episodes, the pair discuss their target, Sagittarius A*, the supermassive black hole at the centre of our galaxy and the subject of this year's Nobel prize in physics, and what happens when you reach the edge of a black hole
Astronomers witness 'spaghettification' of star shredded by a black hole - CNN
(CNN) A black hole enjoyed one stellar spaghetti dinner and astronomers were able to witness the event from 215 million light-years away in a spiral galaxy in the Eridanus constellation.
What Would We Experience If Earth Spontaneously Turned Into A Black Hole?
If a black hole were to appear between the Earth and an observer, the Earth would appear ... [+] gravitationally lensed in a fashion similar to this, dependent on the Earth's position relative to the black hole and the observer. If a black hole were to form from the Earth itself, it would create an event horizon just 1.7 centimeters in diameter.
As it turns out, gravity doesn't need to be the only force: just the dominant one. As the matter collapses, it crosses a critical threshold for the amount of mass within a certain volume, leading to the formation of an event horizon. Eventually, some time later, any object at rest — no matter how far away from the event horizon it initially was — will cross that horizon and encounter the central singularity.
No comments:
Post a Comment