All Questions
Tagged with dark-energy astrophysics
31
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Ejected bodies, dynamical friction and dark energy?
I have a question after reading a couple of papers (https://arxiv.org/abs/1707.06220 and https://www.arxiv-vanity.com/papers/1102.0007/).
Here, the authors seem to indicate that when bodies like stars ...
- 2,472
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Can a receding body due to the accelerated spacetime expansion be "rescued"?
Once a body "crosses" the limit where dark energy wins over gravitational forces (Is there a distance from a gravitational source where the influence of gravity and dark energy are balanced ...
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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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Does Dark Energy contribute to increase the isothermal temperature of plasma in galaxy clusters?
I have a question about this work called "Dark energy and key physical parameters of clusters of galaxies"
There, towards the end, the authors talk about the isothermal velocities and ...
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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 ...
- 2,472
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Tidal effects of galaxies orbiting one another in presence of dark energy?
I recently asked this question about whether there was a "distance" between two galaxies where both the gravitational force and the influence of dark energy would be balanced. The answers ...
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2
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181
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How does dark energy affect the dynamics of galaxy clusters?
Galaxies interact with each other gravitationally (just as every other celestial object) and in many cases they form groups or clusters.
Does the expansion of the universe (or dark energy) affect the ...
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151
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What if dark matter/energy did not exist?
What if dark matter and dark energy did not exist and were only due to a misinterpretation of the red shift of light or a measurement bias?
What would be the implications/consequences?
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Kinetic energy and collisions in cosmology? [duplicate]
Objects in space time can move due to the expansion of spacetime itself (where objects that are sufficiently far apart would recede from each other due to the Hubble flow) and peculiar motions (which ...
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Blueshift caused by dark energy?
Galaxies that are sufficiently far away from our point of view are receding from us due to the accelerated expansion of the universe (supposedly caused by dark energy) and therefore their light is ...
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2
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2
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Why the megaastrophysical objects do not collapse due to their gravitational selfattraction?
At the largest scale in the universe exist formations called filaments which form something like a spider web along the whole universe. But they seem to be quite static. So my question is about the ...
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Could Dark Matter Be Fully or Partially Explained by Gravitational Waves?
This is something I have wondered for a long time and cannot see why it is not a possible solution. Basically, any motion of matter (Mass may be a more accurate description here) through space time ...
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4
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Experimental Evidences against Dark Energy
Subir Sarkar proposed that dark energy does not exist, i.e. the cosmological constant of our universe may not be positive (https://arxiv.org/abs/2106.03119). His stance was based on the 740 type Ia ...
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About the spatial distribution of vacuum energy around strongly gravitating objects in the galaxy
We know that the distribution of vacuum energy is spatially uniform. But we also know that it couples to gravity.
Anything with energy, such as a beam of light is affected by the gravitational field ...
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3
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What is the pressure that dark energy exerts on stars and planets while increasing the distance between them?
What is the pressure that dark energy exerts on stars and planets while increasing the distance between them? I can understand that the pressure should be at a volume scales lower than molecules ...
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