Can Relativistic Mass Create a Black Hole?

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Discussion Overview

The discussion revolves around the concept of relativistic mass and its implications for black hole formation. Participants explore whether relativistic mass, as perceived by an external observer, could lead to the creation of a black hole and the conditions under which this might occur.

Discussion Character

  • Debate/contested
  • Conceptual clarification
  • Technical explanation

Main Points Raised

  • One participant suggests that relativistic mass increases with speed and could theoretically reach the mass required to create a black hole, raising questions about the implications of slowing down from such a state.
  • Another participant argues that the relevant quantity for determining black hole status is not relativistic mass, stating that it is frame-dependent and thus cannot determine whether an object is a black hole.
  • A third participant notes that relativistic mass has not been used by most scientists for decades, indicating a shift in understanding within the physics community.
  • Further, it is mentioned that even Einstein himself moved away from the concept of relativistic mass, citing historical context.
  • Another participant challenges the initial reasoning by using the example of a neutrino traveling at near-light speed, questioning the applicability of relativistic mass in this context and emphasizing the complexity of gravity in relativity, which involves the stress-energy tensor.

Areas of Agreement / Disagreement

Participants express disagreement regarding the role of relativistic mass in black hole formation, with some asserting it is not a valid consideration while others propose it could be relevant under certain conditions. The discussion remains unresolved with multiple competing views present.

Contextual Notes

There are limitations in the discussion regarding the definitions of relativistic mass and black holes, as well as the assumptions made about observer perspectives and the implications of relativistic physics.

Aerodyn
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Hello dear colleagues from the physics forum,

Following question came to my mind, can you tell me which statement (s) is/are wrong?.

Since relativistic mass is weighed with the Lorentz factor for an external observer, it is expected an increase with speed.

Such mass (m1) would tend to infinity with v=c, but before infinity it would go through the mass required to create a black hole. In addition, since the external observer would see the fast object contracted due to its speed, he would see a smaller object with a higher mass, which definitely would increase its density, creating the best conditions for a good black hole soup.

So the external observer would see m1 creating a black hole. What if now m1 decides to slow down until v=0? Would the external observer see m1 escaping from a black hole?

Thank you very much for four support on understanding this strange phenomenaAerodyn
 
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Aerodyn said:
can you tell me which statement (s) is/are wrong?
This:

Aerodyn said:
Such mass (m1) would tend to infinity with v=c, but before infinity it would go through the mass required to create a black hole. In addition, since the external observer would see the fast object contracted due to its speed, he would see a smaller object with a higher mass, which definitely would increase its density, creating the best conditions for a good black hole soup.
The relevant quantity for determining whether an object is a black hole is not its relativistic mass, so the entire quote above is wrong. Whether or not an object is a black hole is invariant, independent of any choice of reference frame. Since relativistic mass is not an invariant, but frame-dependent, it obviously cannot be what determines whether an object is a black hole.

The rest of your post is also wrong since it follows from the above error.
 
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Also, relativistic mass is not used by most scientists for the last many decades. It basically fell out of favor even within Einstein's lifetime.
 
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Aerodyn said:
can you tell me which statement (s) is/are wrong?.
A simple way to see that your reasoning fails is to note that, as seen by a neutrino emitted by the Sun, you are doing 99.99999...% of the speed of light. Do you feel like a black hole?

This kind of mistake is one of the reasons relativistic mass fell out of favour. It leads to too many problems by kind of implying that relativistic physics is just Newtonian physics with a few Lorentz gammas thrown in. It is not. The source of gravity in relativity is a thing called the stress-energy tensor, which includes rest mass and various other forms of energy, but its behaviour is significantly more complex than just relativistic mass, I'm afraid.
 
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