All Questions
Tagged with black-holes cosmology
215
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Frequency sensitivity of gravitational wave interferometer with its armlength and with mass of the mergers
To the best of my knowledge, LIGO is capable of observing gravitational waves (GW) from stellar mass black hole (BH) mergers but not mergers of supermassive black holes. In order to detect the latter ...
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What is the combined explosive force of the Black Hole Era?
It is theorised that in the distant future all matter will gravitationally attracted into Black Holes. The universe will then be seemingly still for a long time until the Black Holes have all ...
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How to calculate the strength ("space force") of dark matter within galaxies?
Let's first have a look at the observed speed within galaxies (source):
On the left side we can see the speed of celestial bodies within galaxies derived by gravity only (gravity is usually created ...
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Is it possible that a black hole has a universe in itself? [duplicate]
Every black hole has a singularity. But the singularity is covered by a thing called 'Event horizon'or ' Schwarzchild Radius'. Our universe is originated from a naked singularity. By naked singularity,...
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Child Universes
I was watching a program on the future of the Universe and it got into the eventual heat death resulting from Hawking Radiation as the last hurdle till nothingness (assuming the unproven theory of ...
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Embedding Schwarzschild in FRLW [duplicate]
Does there exist an exact metric in the literature for embedding the Schwarzschild metric in the Friedmann–Lemaître–Robertson–Walker metric? If so, please give a good reference. Thanks.
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Black holes are maximally entropic but universe predicted to end in heat death instead?
As I understand it black holes have the highest density of entropy per area (and thus per volume for spheres at least) of any form of matter and spacetime.
Also we expect the far future of our ...
- 601
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The relation between the weak gravity conjecture and wormholes
Charged black holes are usually associated with the weak gravity conjecture at extremal limit, according to the well-known relation, i.e. charge to mass ratio. Now my question is that how the weak ...
user212754
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Mathematical coincidence of the Schwarzschild radius of the Universe?
I read here that a black hole with a mass of the observable universe, $M=8.8\times10^{52}kg$, would have a Schwarzschild radius of $r_s=13.7$ billion lightyears.
I immediately noticed that at the ...
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Are the LIGO and VIRGO results consistent with the black hole statistics predicted by cosmology?
Have LIGO and VIRGO recorded enough gravity wave events to cross-check the black hole populations predicted by astrophysics and cosmology?
Basically, we now have another experimental tool to verify ...
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Curvature of spatial 2-section in general form for metric
In this paper (Four-Dimensional Asymptotically AdS Black Holes with Scalar Hair by Gonzalez et. al.), the following standard metric is taken as an ansatz for the hairy black hole:
$$ds^2=-f(r)dt^2+f^{-...
- 2,665
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Falling into a black hole and the big crunch - do they conflict?
In the RI talk https://www.youtube.com/watch?v=_8bhtEgB8Mo at 1:00:30 a member of the audience asks about the race between the big crunch and the rate at which someone falls into a black hole. The ...
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Dark energy stars disproven by Event Horizon images?
I was reading about the hypothesis advanced by George Chapline and Robert Laughlin that black holes might actually be 'dark energy stars', regions where spacetime has undergone a phase transition (e.g....
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Black hole cosmology vs. Big Bang cosmology
The evidence for Big Bang cosmology is an expanding universe. The expansion of the universe is accelerating. Gravity causes acceleration. What evidence is there that proves everything is moving away ...
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Alternative to Dark Energy
If Black Holes consume mass and re radiate it in the form of massless photons the mass of the universe is declining. Could this explain the accelerating expansion of the universe without the ...
