Classification of black holes based on their properties

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Now imagine stars colliding with each other to form a black hole. This formation is not visible to naked eyes because no light or radiation can reach any person at a distance from the black hole.  Even the gravitational collapse of a star would not be visible to a distant observer.

Have you ever wondered whether a person can escape the singularity and go inside a wormhole? Before we answer this question. Let me tell you what a wormhole is. 

A wormhole is nothing but the link between 2 points in spacetime. The above image would give you more clarity. It can connect even to a different universe or some other part of the same universe. 

 A person would not even know whether there is a singularity ahead of him until he hit it. Just understand singularities always lie entirely in the future or entirely in the past! 

The  NO HAIR THEOREM  got its name because black holes don't have hair. What I mean is that our hair contains DNA, it tells everything about us but for a black hole, it's not the case. For example, if an object goes inside the black hole then the details about the object will only stay on the event horizon for some time. We already know that black holes evaporate so when they evaporate they take the information of the object along with them. 

 The no-hair theorem states the physical properties of a black hole. They are nothing but MASS

ELECTRIC CHARGE 

ANGULAR MOMENTUM 

According to their properties, black holes can be divided as 

1. Rotating 

2. Non rotating 

3. Static

ROTATING BLACK HOLES :

                      Roy Kerrin 1963, Roy Kerr, a New Zealander mathematician, described this kind of black hole. So they are also known as Kerr black holes. 

He said that they have 

• no electric charge

• can be characterized by their angular momentum. 

• They rotate at a constant rate.

In these black holes, the rotation rate can be zero as well as non-zero.

 In case the rotation rate is non zero the black hole bulges forward, the faster it rotates the more it bulges.

• Their size and shape depend upon the mass and rate of rotation. 

These rotating black holes can be expressed by the formula:

 Q^2+(J/M)^2< M^2 

• Q represents charge

• J represents the angular momentum

• M represents mass

This is known as the Schwarzschild solution. Any black hole which violates this does not have an event horizon and is known as the naked singularity. But till now every black hole found follows this. 

NON ROTATING BLACK HOLES:

                    Werner Israel 

Werner Israel, a Canadian scientist found these black holes. He said that they are 

• simple perfectly spherical

•  their size depends upon their mass. 

• They are characterized by their charge as well as their angular momentum. 

Now he argued that for a black hole to be formed only a perfectly spherical star should collapse. 

                   Roger PenroseRoger Penrose said that however complicated its shape is, it would end as a perfectly spherical black hole because of the rapid movement of particles involved in the collapse.  

STATIC BLACK HOLES :

               Karl Schwarzschild

Also known as Schwarzschild Blackhole because it was founded by Karl Schwarzschild in 1916. 

• They are characterized only by their mass. 

• They have no electric charge. 

• They are very simple. 

Hooray! We have completed the different types of black holes based on mass (classification of black holes based on mass ) as well based on their properties. 

If you want to know more about black holes and space.

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