General, Research, Technology

Scientists kill stars in a computer simulation. But why?

To unravel the secrets of black holes, the teamAustralian astrophysicists mimics virtual stars - and then repeatedly kills them. But first things first: on April 12, 2019, the LIGO and VIRGO observatories discovered gravitational waves - ripples in space-time that appeared as a result of an unusual space incident - the merger of two black holes. Unlike the ten previously described cases in which two black holes had equal or almost equal mass, in this event, called GW190412, two different black holes collided: the mass of one of them exceeded the mass of the other three or four times. Let me remind you that black holes are the last stage in the evolution of massive stars, which can last millions of years. This is why computer simulations can tell scientists a lot about extreme cosmic events.

The spinning black holes in the artist's view look like this

Double star or double system Is a system of two gravitationally coupled stars that rotate in closed orbits around a common center of mass.

Black hole fusion

Scientists from the ARC Center of Excellence forGravitational Wave Discovery (OzGrav) has provided the world with an alternative explanation of the recently discovered black hole fusion. The article was published in the Astrophysical Journal Letters. According to the results, if isolated paired stars orbiting each other give rise to merging black holes, then they naturally create Original, heavier black holes that rotate very slowly.

Researchers also note that at least one of the merging black holes had to rotate around its axis.

Guided by the best modern modelsevolution of massive stars in binary systems, we can conclude that a more massive or “heavy” black hole in it rotates very slowly, while a “lighter” one, on the contrary, is very fast, the authors of the scientific work write.

See also: Scientists have recorded the most powerful supernova explosion ever recorded

Let me remind you that one of the most powerful types of explosionsin space - this is a supernova explosion - a phenomenon that marks the last stage of the evolution of massive stars, accompanied by a sharp change in the brightness of the star with subsequent attenuation. Despite the fact that a supernova explosion may seem like the birth of a star, in fact it is her death.

A black hole spinning in orbit with a much smaller partner spawned gravitational waves

You can find even more articles about our planet and other space objects that plow the open spaces of the cosmic ocean on our channel in Yandex.Zen. There are regularly published articles that are not on the site.

Collapse supernovae - one of the brightest objects in the Universe,which also mark the birth of black holes and neutron stars. The gravitational waves discovered by researchers help them better understand the astrophysics of black holes and neutron stars. Be that as it may, simulating these devastating events again and again, scientists hope to understand how real black holes form and behave.

When the gas shell of a star burststhe extreme tidal forces exerted by the twin star, the slowly rotating central core of the star remains behind and eventually collapses into a slowly rotating black hole. The same process, as a rule, is applicable to the second, lighter star, which ultimately collapses into a smaller black hole. Although this interpretation is difficult to confirm, future studies of black hole mergers will allow more accurate testing of this model.

Join in a discussion of this and other amazing discoveries of astronomy in our Telegram chat

Why do astronomers need a computer simulation?

While gravity wave detectorsdetect cosmic events such as the birth of a new black hole or the merger of two black holes in the vast expanses of an infinitely expanding universe (mind you, with acceleration), there are events that our devices are not able to detect. This is where computer simulations come to the fore. By simulating the death of stars tens of times more massive than our Sun, researchers can predict what the gravitational waves emitted by these explosions will look like.

This is how a supernova explosion looks like

To detect the collapse of a supernova nucleus using gravitational waves, astrophysicists must predict what the signal of the gravitational wave will look like. Supercomputers simulating these spaceexplosions allow researchers to understand their complex physics. Moreover, the simulation results make it possible to predict what detectors will see when a star explodes and determine its observable properties.

By the way, in one of the articles devoted tospace exploration using computer programs, I talked about the amazing discovery of scientists who created eight million universes inside a computer. I recommend reading it.

The results obtained, as Futurism, citing a research press release, will help astrophysicists determine the waves emitted by a real supernova with a nuclear collapse. Thus, when the next generation of gravitational wave detectors will be built, astronomers will not search blindly.