How Some Stars Disappear and Disappear in Space

TOV LIMIT

Sometimes magicians suddenly bring out a bunch of flowers when they have nothing in their hands, and even though I know it's just a magic trick, I get great pleasure from watching such shows.

I think everyone enjoys magic shows.

What a beautiful sleight of hand magicians have.

A bunch of flowers appears and then one more move and the bunch of flowers disappears.

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Is it really possible to destroy something?

Or conversely, is it possible to create something out of nothing?

God did it! He created us, the whole universe out of nothing! 

He told everything we see around us to happen and everything happened at that moment! 

Although, according to some religious sources, it didn't happen immediately, it took God a certain amount of time.

But God is the only powerful being who can create something out of nothing!

Of course, religious beliefs aside, something similar to destruction is possible in the universe, not creation. In fact, we can say that some things come into existence out of nothing.

Of course, what I'm talking about is not exactly annihilation, but if you want to call it concealment, like magicians do, if you want, minimizing it to a level that we cannot see!

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I have written some articles about neutron stars before. 

Yesterday, I wrote about the neutron, as those who have read it know.

Today, I wanted to go a little deeper into neutron stars.

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What is a neutron star? 

We also call it a pulsar. We can also say pulse, which we call pulse in English, is the origin of the word pulsar.

Neutron stars are celestial bodies composed of neutrons only.

Neutrons, as I wrote yesterday, are by themselves unstable atomic particles. They decay into protons and electrons in less than fifteen minutes. If you remember, this decay is called beta decay.

Even though they are unstable particles on their own, neutrons can stay together as a neutron star.

Of course, in addition to the strong nuclear force that holds them together, the gravitational force also has a great effect. 

There is no matter in the world that consists only of neutrons. In other words, with the strong nuclear force alone, a few neutrons cannot come together and stay together. 

Therefore, we cannot observe anything made of neutrons alone. 

But there are neutrons emitted from radioactive materials, and they decay after a while.

Since there are no free electrons in their structure, they can only survive when there is a stable atom in the nucleus with protons.

Therefore, neutron stars do not resemble any matter that we know, that we can touch with our hands or see with our eyes.

But they exist in the universe.

Neither hydrogen, nor carbon, nor oxygen, nor any other known matter is present in the structure of neutron stars. 

But they are very dense celestial objects!

We call them pulsars because they revolve around themselves very fast and emit periodic magnetic rays. 

The periods of these beams are so regular that when they are detected from such a great distance, you can almost perfectly synchronize the magnetic beams of pulsars.

In fact, the reason why they emit periodic magnetic rays is that the magnetic radiation emitted from their poles reaches us in a certain period with the wobbling motion they make while rotating.

If this magnetic beam were to fall directly on us, we would not be able to avoid being shattered.

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I'm saying there are no protons, no electrons, only neutrons in the structure of these stars.

Electrons and protons are charged particles, you know. One carries the usual minus charge and the other its opposite, the positive charge.

In normal matter, electrons move around the nucleus of the atom at a considerable distance and for some reason they don't fall into the nucleus. I have written before that the reason for this is the momentum of the electrons spinning around themselves.

However, if you remember, the force of attraction between these negative and positive electric charges, which we call electromagnetic charges, was quite high, but thanks to their spin, the electrons did not fall into the nucleus.

The electromagnetic force is actually quite high.

Because the distance between electrons and protons is really very large. 

If we want to make a comparison, the distance between the electrons and the nucleus is like the distance between a soccer ball placed in the center of a soccer field, at the starting point, and a ping-pong ball placed at the farthest point of a turbine.

The electric charge actually has such a strong effect, imagine that the soccer ball in the middle can affect that ping-pong ball far away.

After all, what we call atoms are made up of electrons, protons and neutrons, and when they come together, they take up as much space as if we brought football fields with their turbines side by side. 

You can think of it as if the land of a country is made up of stadiums lined up side by side.

Neutron stars, on the other hand, are like the soccer balls in the middle of each stadium.

The electron collapses into the proton under the pressure of the supernova explosion and out comes the neutron, an uncharged particle. The protons undergo beta decay.

If we go deeper, you know how we say there are quarks inside neutrons and protons, imagine that somehow electrons change this quark arrangement and turn the proton into a neutron.

The result is a tiny soccer ball in the middle of a huge stadium. But it's a soccer ball equivalent in mass to the mass of the stadium.

It's not the same thing, but you can visualize a soccer ball that weighs as much as a stadium.

You can also call the formation of these neutron stars, where the volume of the atom is reduced to a tiny speck and the whole world is as small as a soccer ball.

It's like a magic show. 

The huge star first explodes, but all the atoms inside collapse under the pressure. 

Since there are no protons and electrons left, only a tiny but very dense collection of neutrons remains.

It's like something that exists disappearing.

In reality, of course, nothing disappears, it just becomes a soccer ball with the mass of the earth, whereas at the beginning it was a star the size of the earth.

Of course the mass of the earth is not enough to turn into a neutron star, the mass of the earth and even the pressure at its center is too small for protons and electrons to fuse. Although nuclear reactions are thought to take place at the center of the Earth.

Still, much larger masses are needed for it to turn into a neutron star.

Even the Sun has too little mass to turn into a neutron star.

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Scientists are currently working on calculating the right mass size for a star to become a neutron star.

In fact, there have been studies on this subject for a long time. However, the calculations are so complicated that the exact value cannot be calculated. The calculated value also shows deviations when checked with celestial bodies detected in space.

Tolman, Oppenheimer and Volkoff had already done this calculation in 1939, and the result of this calculation was called the TOV limit, inspired by the initials of the surnames of these three scientists.

However, as I said, the calculation was later re-done with changes in the preliminary assumptions and the limit values were changed in 1996.

In the calculations, there is a ratio to the mass of the sun. 

In the original calculation, the lowest possible mass was 0.7 solar masses, while in the later calculations made in 1996, this ratio was calculated as 1.5-3 solar masses.

Today's research is more of a study of black holes, which are the next stage after neutron stars.

Of course, what I call this research is all those complicated calculations made by theoretical physicists.

The largest neutron star ever observed in the universe was 2.08 times the mass of the sun. 

Although it doesn't produce light like a normal star, this mass was somehow detected by magnetic waves and for a long time it was predicted that the largest neutron star could be of this mass.

The smallest detected black holes start from 5 times the mass of the sun.

These are values that can be observed and practically detected in the universe. Calculations give different results.

So scientists sat down and decided to redo this calculation. 

When does a star remain a neutron star after a supernova explosion?

When does it turn into a black hole?

This is the question of the magnitude of the transition! 

All these studies are being carried out again these days to find out whether a new celestial object, presumably a neutron star, is a neutron star or a black hole.

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What is the difference?

Black holes are so dense in mass that even light can no longer escape their influence. 

The internal structure of black holes is not yet known. 

Theoretical physicists have some predictions, of course, but it wasn't even that long ago that Hawking radiation was discovered. It wasn't that long ago that the deceased passed into eternity.

The behavior of matter at such a high pressure is not yet known with the current formulas. Perhaps quarks also implode at such high pressures and behave completely differently. It is not easy to know all this.

Neutron stars are also very dense celestial objects, but it is known that the effect of neutron stars on light is not like that of a black hole; light can pass around neutron stars with some bending and continue on its way.

I guess the other stars in the universe are not close enough to be affected by neutron stars. 

At least one neutron star has not yet been observed to absorb another star.

The rest are probably quite similar. Neither emits light, and no visible observations are possible.

According to the latest calculations, neutron stars can be up to 2.4 times more massive than the sun.

The observed magnetic radiation, on the other hand, belongs to an object 2.2 times the mass of the sun, meaning that these signals are probably coming from the most massive neutron star ever observed.

The largest neutron star ever detected may have been found.

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Still, even if a star with a mass 2.4 times that of the sun is considered the limit, it is not known whether this is the limit necessary for a star to become a black hole. After all, the smallest black hole ever detected has 5 times the mass of the sun. 

There is a big gap between the calculations and the observations.

Maybe one day a black hole with a smaller mass will be detected. 

Maybe one day someone will come along and do the math more accurately.

We probably have many years ahead of us to solve this mystery.

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Is it important to get this limit right?

My answer to this question might be as follows. Imagine that you hit a ceramic vase with your fist, each time with more force, and at some point the vase will break. This limit is like a breaking point. 

Of course, it is important to be able to calculate this limit correctly and verify it with observations, at least in terms of verifying some formulas.

But if you say what does this problem concern me, then there is nothing I can tell you.

Let me end this article by saying stay with science.

Love and respect to everyone from Moscow.