Rebuttle of Black hole arguments

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Discussion Overview

The discussion revolves around the formation of supermassive black holes, particularly questioning the feasibility of their formation through the merging of two stellar black holes. Participants explore various theories, initial conditions, and mechanisms related to black hole mergers and early universe conditions.

Discussion Character

  • Exploratory
  • Debate/contested
  • Technical explanation

Main Points Raised

  • Some participants suggest that initial conditions play a crucial role in whether two stellar black holes can merge, noting that they might scatter instead of interacting.
  • There is mention of a thermal radiation bath that could influence the dynamics of black hole mergers, raising questions about energy loss and mass considerations.
  • One participant highlights that the mass of stellar black holes is significantly lower than that of supermassive black holes, which complicates the merging scenario.
  • Another viewpoint discusses the formation of supermassive black holes in the early universe, proposing that gas could rapidly coalesce due to gravitational attraction.
  • Some participants reference cosmological simulations that suggest "seed" black holes must be placed in early galaxies to account for the existence of supermassive black holes today.
  • There is a discussion about the second law of thermodynamics in relation to black hole mergers, with one participant arguing that the final entropy of the resulting black hole must be greater than the sum of the entropies of the merging black holes.
  • Another participant questions whether there is a mass multiplier effect during black hole mergers, contrasting this with previous claims that black holes do not gain significant mass through merging.

Areas of Agreement / Disagreement

Participants express differing views on the mechanisms and conditions under which supermassive black holes can form, with no consensus reached on the validity of merging stellar black holes as a pathway to their formation.

Contextual Notes

Limitations include unresolved questions about the specific conditions required for black hole mergers, the role of mass in these processes, and the assumptions underlying various theoretical models.

rubecuber
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Hi, my astronomy teacher want's us to give him some possibilities as to why supermassive black holes cannot form by the merging of two stellar black holes

Any help would be appreciated,
Thanks,
rubecuber
 
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Well one possibility surely is initial conditions. They might scatter off one another and not interact. Only in the case of a head on collision or in the case of a decaying orbit might they intersect.

The latter case is also a little peculiar. There is a thermal bath of radiation exerting an radially outward push so that may or may not cancel energy loss due to friction. there's also the question of mass. I mean 2 stellar black holes aren't even close to the mass range of a supermassive bh.

Anyway I am rather surprised your teacher gave you this question, as its completely nontrivial. Blackhole mergers are a poorly understood area and the subject of very active research. Some people expect there to be some sort of very violent processes going on.
 
Collisions between black holes are about as unlikely as collisions between stars.
 
Thanks, but now i have a few questions as to how a supermassive black hole could have formed really early on in the universe by a sudden imposion of a bunch of gas due to the gravitational attraction at such high speeds. If i poorly explained this, then the guy who thought of this teaches at oxford, and maybe that will help. How could the gas just suddenly glob together and form a supermassive black hole.
Thanks,
rubecuber
 
cadnr said:
Collisions between black holes are about as unlikely as collisions between stars.
it could happen
 
Its a valid question. Super massive black holes are at the centers of galaxies and weigh in at a million to a billion times the mass of our sun (or a stellar mass black hole). How these super massive black holes built up over time is an active area of research. I know that in the latest cosmological simulations "seed" black holes that are already quite massive must be placed "by hand" in early galaxies to produce super massive black holes that produce observables like the active galactic nuclei / quasars seen today.

One idea is primordial black holes were produced during the big bang and had a long time to accrete material. Another is that some of the first generation of stars, which were more massive than stars like our sun due to the low metal content, collapsed directly into black holes. There is a very bimodal pattern in the observed black holes (really big guys at the center of galaxies or little wimpy guys in binary orbits with other stars) leading some to assume that there are different processes that lead to their creation.
 
rubecuber said:
Hi, my astronomy teacher want's us to give him some possibilities as to why supermassive black holes cannot form by the merging of two stellar black holes

Any help would be appreciated,
Thanks,
rubecuber

i have a suitable answer for ur question. just consider the event horizon as the entropy of a system. according to the 2nd law of thermodynamics during the merger of two systems the final entropy of the resultant system is equal or more than the sum entropies of the two merging syatems. similarly the two merging black holes can form supermassive black holes which wil have its event horizon equal or more than the sum of two event horizons of the combining black holes.
 
pseudo said:
i have a suitable answer for ur question. just consider the event horizon as the entropy of a system. according to the 2nd law of thermodynamics during the merger of two systems the final entropy of the resultant system is equal or more than the sum entropies of the two merging systems. similarly the two merging black holes can form supermassive black holes which wil have its event horizon equal or more than the sum of two event horizons of the combining black holes.

?
is there a mass multiplyer in the merging system
when I asked so time ago
people here said
NO black holes do NOT radicaly gain mass in merging
BUT i THINK MR 'E's laws on near light speed mass increase
is a bigger clue then the 2nd law of thermodynamics
and don't think they get that big eatting dust
 
Code:
ray b said:
?
is there a mass multiplyer in the merging system
when I asked so time ago
people here said
NO black holes do NOT radicaly gain mass in merging
BUT i THINK MR 'E's laws on near light speed mass increase
is a bigger clue then the 2nd law of thermodynamics
and don't think they get that big eatting dust

i know ur right .there can be a factor of mass multipyer bcoz the final area of the eventhorizon directly varies to its mass. it is given by, e=2gm/c^2 where e is the event horizon.
 

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