Neutron stars can hide black holes inside

Neutron stars at the center of the galaxy may be devouring primordial black holes and being destroyed by them.
Roberta Duarte

Roberta Duarte Meteored Brazil 05/01/2024 12:05 6 min

The two most extreme objects in the universe are black holes and neutron stars. Objects belong to a category called compact objects and are remains of massive stars. When stars much larger than the Sun reach the end of their lives, they collapse into these smaller but higher-mass objects.

There are several categories that a neutron star can be in and one of them is called pulsars. The pulsars are neutron stars that have angular momentum misaligned with the magnetic field. In this way, the stars function as authentic cosmic lighthouses with great precision. Other types are magnetars.

Cosmic Ying and Yang: if there are black holes, the theory supports the existence of white holes

Cosmic Ying and Yang: if there are black holes, the theory supports the existence of white holes

A group of researchers in Italy has published an article that investigates the possibility of neutron stars capturing primordial black holes. The proposal is presented as a possible solution to the problem of the lack of pulsars in the galactic center. Additionally, this could be a clue as to where primordial black holes are hiding.

galactic center

The center of the galaxy is a very extreme and chaotic environment where they live stars, neutron stars and black holes. In the center is a supermassive black hole called Sgr A* with 4 million solar masses. There are some stars orbiting the central black hole, for example the star S2 which appears to form a dance around the object.

representation of the orbit of the star S2 around a black hole
Orbit of the star S2 around the central black hole of the Milky Way. Credit: Max Planck Gesellschaft

Despite its mass and gluttonous reputation, the supermassive black hole only interacts with a small region. The accretion rate of Sgr A* is low compared to that of black holes of this type. Another famous object is the magnetar PSR J1745-2900, which attracts attention because, in addition to orbiting the black hole, it is apparently the only neutron star in the region.

Problem with pulsars

The lack of pulsar observations, in a region where there is a greater density of objects, is something curious for astronomers. With the exception of the PSR J1745-2900 magnetar, radio signals are not received from neutron stars such as pulsars. Something that does not happen in other regions of the galaxy where pulsar signals are received.

Discover the collisions of neutron stars that can destroy a planet

Discover the collisions of neutron stars that can destroy a planet

This is a problem within astronomy, and there have arisen some hypotheses to try to explain this lack of observations. Some suggest that neutron stars eventually destroy themselves through gravitational interactions. These “destroyed” neutron stars would be difficult to observe, but that alone would not solve the problem completely.

Neutron stars that hide black holes

An article presented by a group of Italian astronomers suggests that neutron stars may have captured primordial black holes less than 1 solar mass. In this way, the black holes would feed on the interior of the star, encompassing everything, and instead of a neutron star, only a black hole would remain.

Using models and simulations, the team was able to demonstrate whether pulsars would be able to capture primordial black holes. In the simulations, as soon as the black hole was captured, it was pushed toward the center of the neutron star, as expected. This result shows that this would be possible in these regions of the galaxy.

Primordial black holes

Furthermore, the solution would also answer the question of where are the primordial black holes. This type of black hole has never been observed before and could range from the size of an atom to the size of planets or small stars. They would have formed in the early moments of the Big Bang when density fluctuations collapsed.

youtube video id=PJ7W2JOeeHE

Primordial black holes are popular as an explanation for dark matter. As they would have masses that can reach 100,000 solar masses, a large population of primordial black holes could represent the mass of dark matter. However, the lack of observations of these objects makes this hypothesis unlikely.

The problem persists

The paper’s results show that even if neutron stars captured black holes, This solution alone would not solve the problem of the lack of neutron stars in the galactic center. A combination of different hypotheses would have to be proposed to explain this disappearance.

Likewise, the lack of evidence for the existence of primordial black holes remains an open question. Some future telescopes may be able to answer some of these questions.

Sources and references of the news:Caiozzo et al. 2024 Revisiting Primordial Black Hole Capture by Neutron Stars arXiv.

For Latest Updates Follow us on Google News


PREV The Government clarified what the prepaid discount should be like and a ruling puts returns at risk
NEXT Rodolfo D’Onofrio left a particular message for Enzo Pérez after eliminating Boca