Rebuttle of Black hole arguments

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SUMMARY

This discussion centers on the formation of supermassive black holes and the limitations of merging stellar black holes. Key points include the assertion that stellar black holes lack the necessary mass to merge into supermassive black holes, which typically range from one million to one billion solar masses. The conversation highlights the role of primordial black holes and the accretion of material over time as potential formation mechanisms. Additionally, the discussion touches on the entropy of merging black holes and the implications of mass increase during mergers, referencing the laws of thermodynamics and relativistic effects.

PREREQUISITES
  • Understanding of black hole physics, specifically stellar and supermassive black holes.
  • Familiarity with the laws of thermodynamics, particularly the second law regarding entropy.
  • Knowledge of cosmological simulations and the concept of seed black holes.
  • Basic principles of general relativity, especially regarding mass-energy equivalence.
NEXT STEPS
  • Research the formation mechanisms of primordial black holes in the early universe.
  • Study the role of gas accretion in the growth of supermassive black holes.
  • Explore the implications of the second law of thermodynamics on black hole mergers.
  • Investigate the effects of relativistic mass increase during high-energy collisions in astrophysics.
USEFUL FOR

Astronomy students, astrophysicists, and researchers interested in black hole formation and the dynamics of cosmic structures.

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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