All Questions
Tagged with gravity astrophysics
172
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Can there be structures made from neutrinos that can have angular momentum?
Would it be possible to eventually have structures made from neutrinos somewhere in the universe, as it is indicated in this question (Are neutrino stars theoretically possible?), like halos of ...
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Turnaround radius being increased in fast collapsing regions?
In the context of formation of large-scale structures, there would be a turnaround radius where expanding matter would detach from the Hubble flow and start to collapse (https://www.aanda.org/articles/...
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Interplay between gravity and cosmic expansion causing collapse of large-scale structures?
As far as I understand it, in the context of large structure formation, the interplay between gravity and cosmic expansion can cause certain anisotropies in voids that can make them collapse (https://...
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Stellar Core Collapse Speeds
If gravity determines the speed of free falling objects, but stellar core collapses happen much faster than the speed of free falling objects, wouldn't that indicate that stellar core collapses are ...
user394592
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Can the integrated Sachs-Wolfe and the Rees-Sciama effects have any influence on matter?
CMB photons can be affected by the expansion of the universe through the linear integrated Sachs-Wolfe effect (ISW) 1 and the non-linear ISW effect or also called Rees-Sciama effect 1.
In particular, ...
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What would the collapse of a neutron star into a black hole look like from the center?
I have read this question (unfortunately this mentions supernova and not black hole):
If it it the latter, then the instabilities that lead to the collapse of a neutron star would begin near the ...
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Dark energy, bound systems and orbits...?
As far as I understand it, dark energy can affect bound systems at cosmological scales (How does dark energy affect the dynamics of galaxy clusters?) effectively modifying their orbits.
This ...
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At the TOV limit (almost black hole), how much of a neutron star's primordial mass has been converted to energy?
The following rough approximation seems to show a neutron star at its Tolman–Oppenheimer–Volkoff limit of 2.17 solar masses and 12km radius, has gravitational binding energy on the same order as its ...
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Effects of dark energy in the kinetic energy of a body?
If I launch a ball into the sky it would reach a distance after which it would return into the ground transforming the potential energy into kinetic energy as it hits the ground
This is similar to ...
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Mass Conversion from Potential Energy in Merging Black Holes
I am considering a hypothetical system of two black holes, each with a mass of 10 solar masses, uncharged and without spin (for the sake of simplification). Initially, they are separated by a distance ...
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Is gravitational binding energy or gravitational self-energy a source of gravity?
The gravitational binding energy or self-energy of a system is the minimum energy which must be added to it in order for the system to cease being in a gravitationally bound state. Equivalently, the ...
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In a binary black hole system, can one of the black holes get ejected before merging in some contexts?
As it is said here (https://physicsworld.com/a/couple-emerges-from-trio-of-supermassive-black-holes/) a system of two orbiting black holes could disrupt the gas and stars at the center of the galaxy ...
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Why doesn't the lack of electromagnetic repulsion between dark matter particles result in the formation of black holes? [duplicate]
From what I've researched dark matter isn't subject to electromagnetic forces, which I'm assuming implies that there is a lack of electromagnetic repulsion between dark matter particles.
If there's ...
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Time of collapse of stellar dust cloud
A stellar gas cloud collapses onto itself once it reaches Jean's mass, and the time it takes for said cloud to collapse is given by: $t_{coll}=\sqrt{\frac{3\pi}{32G\rho_0}}$, where $\rho_0$ is the ...
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Age of the universe due to expansion
"If gravity working on matter is the only force at work on large scales, then the attactive force of gravity will act to slow the expansion. In this case, the universe was expanding more rapidly ...
