Questions tagged [dark-energy]
Dark energy is the unknown form of energy that drives the acceleration of the universe's expansion.
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Why are dark matter and dark energy favoured over changes to our physical models? [closed]
I am instinctively skeptical of the existence of "dark matter" and "dark energy". Together, they strike me as being analogous to luminiferous aether -- something that was invented ...
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Does dark energy increase tidal forces in cosmic voids...?
I would like to ask you some questions I have about some interesting work I was reading (https://arxiv.org/abs/1205.4238 & https://academic.oup.com/mnras/article/527/4/11962/7457744) where the ...
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Klein-Gordon equations in quintessence
I'm studying the quintessence model from a dynamical system point of view. I denoted the scalar field for the dark energy as $\phi$, so I have the following Klein-Gordon equation for the field $$\...
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Measurement of the Cosmological Constant
Is there some way to measure Lambda, the cosmological constant, independent of $H_o$,
the Hubble constant and omega_lambda, the Dark Energy density? A standard equation for calculating Lambda, ...
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If the observable universe had only one galaxy, how would people know the expansion of the universe?
Hubble measured high redshifted galaxies to discover the cosmic expansion. In a hypothetical universe where only one galaxy exists, would there still be observational evidence for the Big Bang theory? ...
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Electromagnetic field pressure
Wikipedia gives that maxwell tensor components have minus in the electromagnetic stress energy tensor https://en.wikipedia.org/wiki/Electromagnetic_stress%E2%80%93energy_tensor. That mean the ...
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Will cosmic microwave background become invisible in the future?
If my understanding of CMB and Hubble's Law is correct, then CMB photons emitted from more than ~14.4 Glyr during Recombination Epoch would not reach us. The reason is this would correspond to Hubble'...
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Does the accelerated expansion of the universe have any effects in the orbital precession of galaxies? And in their eccentricity?
I found several papers (https://iopscience.iop.org/article/10.3847/2041-8213/ace90b; https://link.springer.com/article/10.1134/S1063772920100054; https://arxiv.org/abs/gr-qc/0301057; https://arxiv.org/...
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Does energy exist on its own? [closed]
So to my understanding as a layman is that energy transfers from one material to another (I guess that's why there's potential and kinetic energy), for example photons to solar panels. Now my question ...
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Cosmological constant, dynamical friction and structure formation?
I would like to ask a question about an interesting article that I found (https://repositorio.unesp.br/server/api/core/bitstreams/b8a5a5b8-4b3b-4198-9f5d-bf69431db1ae/content)
In the context of ...
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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 ...
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Does dark energy have mass?
For personal writing purposes, I’ve been researching dark energy, amongst other similar subjects. I’ve found it hard to discern whether or not we have any conclusive answers or generally accepted ...
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Suppose the universe from our big bang is surrounded by many distant blackholes with each a mass of sextillions of suns. Could it explain dark energy?
Could dark energy "simply" be from multiple distant universe-scale mass black holes, that are there "all-around" the big bang?
Scattered apparently randomly, throughout infinity (...
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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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Is Dark Energy Taking Over?
First question, trying to keep it simple 😃
Because it's constant it grows in magnitude as the universe expands, whereas normal matter does not? Is this accurate as far as we know?
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