[ad_1]
A newly developed solution to the equations at the heart of Albert Einstein’s most innovative theory suggests that a hypothetical star called a “nestor” could be a gravitational star like a Russian tea doll, also known as a matryoshka doll, or It suggests that it may be made from stacks of “Gravaster”.
One of the most impressive things about Einstein’s 1915 theory of gravity, general relativity, is how many incredible cosmic objects its central equation predicted.
General relativity not only predicts that gravity arises from objects of mass that curve the fabric of space-time, but also gives rise to the theory of black holes and the ripples they create within that structure, called gravitational waves. Both of these things have been confirmed by observation. But anti-black holes called white holes and “wormholes” that could potentially connect white holes and black holes are other ideas based on general relativity that remain purely theoretical. Time will tell whether Einstein will again be vindicated on this point.
To this end, another theoretical idea that emerged from general relativity in 2001 is the concept of “gravastars,” or compact celestial bodies with dark energy cores. Dark energy is the force that appears to be accelerating the expansion of the universe. Scientists believe that in Gravaster, dark energy exerts negative pressure to protect the star from its internal gravity.
Related: 10 discoveries that prove Einstein was right about the universe and 1 that proves he was wrong
And now a new solution to general relativity suggests another interesting aspect of such so-called gravastars. You can also stack them to create a series of “nests”.
“Nesters are like Matryoshka dolls. Our solution to the field equations allows a series of nested Gravasters,” says one of the solution developers, a theoretical physicist at Goethe University. Daniel Jampolsky said in a statement.
Meet Gravaster (kind of like a black hole, but different)
Only a year after the theory of general relativity was announced to the broader scientific community, Karl Schwarzschild, a German physicist serving on the front lines of World War I, published the first solution to the field equations. has been developed. This surprised even Einstein, who believed that solutions would take time. It takes years to develop.
Schwarzschild’s solution had two features that ultimately led to the concept of a black hole. German physicists predicted that if you move away from a massive object at a certain radius, the speed required to escape from that object must exceed the speed of light.
For most objects, this Schwarzschild radius lies deep beneath their surface. For example, the Sun is located 1.9 miles (3 kilometers) from the star’s center, which has an overall radius of 434,000 miles (700,000 kilometers).However, if a star collapses and its radius becomes smaller than the Schwarzschild radius, the result is that the object outside A boundary line that even light cannot escape. This led to the concept of a black hole event horizon.
More interestingly, Schwarzschild’s solution suggested that there may be a point at which matter becomes so dense that general relativity itself must break down. This becomes known as the central singularity of the Black-His Hole, and all known physical theories become moot.
These concepts were validated in 1971, when humans discovered the first black hole, and then in the 2000s, when a powerful radio source at the center of the Milky Way galaxy actually became a supermassive object with a mass 4.5 million times that of the Sun. discovered to be a massive black hole. This giant cavity in our galaxy is called Sagittarius A* (Sgr A*).
The visual form of a black hole as described by general relativity was revealed in 2019 when Event Horizon released an image to the public of a ring of glowing material around the supermassive black hole at the center of the galaxy Messier 87. , incredibly confirmed. Telescope collaboration.
Gravasters, or “gravitational condensation stars,” were theorized by Pavel Mazur and Emil Mottola in 2001 as an alternative to black holes.
From a theoretical physicist’s point of view, gravasters have several advantages over black holes. They are very similar, as they are almost as compact as black holes, and their surfaces have essentially as strong a gravitational influence as black holes. However, there are important differences. First, Gravaster does not have an event horizon, so it does not contain light, and therefore information, behind a unidirectional “screen.” Second, it is believed that Gravaster’s heart does not have a singularity, but instead has a heart of dark energy.
This recipe for gravastar, prepared by Mazur and Mottola, contains an almost infinitely thin skin of an ordinary substance that is difficult for scientists to explain. Nester et al. do away with this, suggesting that the “stacking” bits lead to a somewhat thicker shell of material.
“It’s a little easier to imagine that something like this could exist,” Jampolsky said.
But of course, just because the general relativity field equations allow for some object to exist in the universe, that doesn’t mean that the object must exist.
“Unfortunately, we still do not know how such gravastars are created,” Goethe University theoretical physicist Luciano Rezzola, co-inventor of the Nestor theory, said in a statement. “But even if nesters do not exist, exploring the mathematical properties of these solutions will ultimately help us better understand black holes.”
Studies like this are helpful because even if the leading theories don’t work, they reveal impressive paths that have emerged from theories first considered more than 100 years ago.
“It’s amazing that 100 years after Schwarzschild presented the first solution to Einstein’s field equations based on general relativity, it is still possible to find new solutions,” said Resola. concluded. “It’s like finding gold along a path that many have explored before.”
The study was published February 15 in the journal Classical and Quantum Gravity.
First posted on space dot com.
[ad_2]
Source link
