All Questions
Tagged with cosmology dark-matter
265
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Gondolo-Gelmini Change of Variables
In the article Cosmic abundances of stable particles: Improved analysis, P. Gondolo and G. Gelmini, Nucl. Phys. B 360 (1991), p. 145-179, they convert $\rm{d}^3p_1\rm{d}^3p_2=2\pi^2p_1p_2\rm{d}E_1\rm{...
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3
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Is it possible that dark matter and dark energy come from the same dark particle?
I've skimmed articles/blogs and watched videos around this issue, and the universal consensus is that dark matter and dark energy are two different things >> DM is attractive while DE is ...
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Number of interaction of early universe
I am reading An introduction to particle dark matter by Stefano Profumo. I am struggling on a derivation.
As given from the text, in the early universe $\frac{\dot{T}}{T}=-\frac{\dot{a}}{a}=-H$, ...
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What is meant by dark matter being non-relativistic and why is this?
What does it mean by dark matter being non-relativistic and why is it non-relativistic?
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Fermilab's results and a fifth force [duplicate]
On today's news, it says that Fermilab have done measurements on the spin of muons and that they are measured to wobble faster than expected according to current physics theories.
Apparently this may ...
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What does it mean for CDM to "decouple from baryons"
I am currently working on my Final Year Project as an undergraduate, mostly intended to be a review of $\Lambda$CDM model and some of its modern challenges.
When talking about Cold Dark Matter I ...
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Why is the distribution of Dark Matter in the Universe inhomogeneous?
As far as I know, there exist galaxies containing lots of DM and other galaxies with almost no DM at all.
This implies that the distribution of DM in the Universe is inhomogeneous. Do we have any idea ...
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Why a decaying dark matter?
I'm reading some papers (model, exp and model) that are dealing with decaying models of DM, why is it interesting? What are the signatures that this type of model can give to observe DM?
I am ...
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From which dark matter made of? [closed]
Observations indicate that about 90 percent of the matter itself in the
universe is made up of dark matter. Exactly what kind of things dark matter made of?
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1
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What if dark matter occupied three other dimensions and it could only interact with our three dimensions through gravity and time? [closed]
I recently thought about dark matter existing in three other dimensions similar to ours but wasn't sure if it was logical. It would be of great help if someone would give me a clear insight into this ...
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What properties of dark matter can we derive from each of the available methods for probing the physics of dark matter?
This is probably a long shot but it's worth trying. My question is the following:
What properties of dark matter can we derive from each of the available methods for probing the physics of dark matter?...
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Why don't cosmological observations tightly constrain cross-sections for direct detection of dark matter?
A reasonably recent review of dark matter detection is given by Liu et al., 2017, https://arxiv.org/abs/1709.00688 . I've reproduced their figure 1 below.
The cross sections on this graph span 13 ...
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2
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Why can't Dark Matter be curvature without a proximal mass source? [closed]
I don't understand why Dark Matter or MOND/"gravity works different on bigger scales" are the only options to explain the observational data.
Why can't it just be curvature without a "...
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Possibility of reaching equilibrium starting with a nonequilibrium initial condition in the early radiation-domination
Update after @knzhou's comment
If in a theory, the coupling of the dark matter (DM) field to the Standard Model (SM) fields is small enough, the rate of interaction of the DM particles in the ...
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Hydrogen-One (HI) Image and R-band
In the paper below, on page 3, it says "In the lack of HI image, we use the r-band b/a ratio to correct for the inclination". Am I correct in thinking that what this means is that if we ...
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