Matter not observed directly but inferred to exist based upon its gravitational effects

learn more… | top users | synonyms

2
votes
2answers
296 views

Could dark energy be heat? Could dark matter be stuff that is not seen because of its refraction limits?

Heat has to go somewhere. Would the light and heat of the stars in the universe amount up to being dark matter ...and dark energy ... Dark matter would just be small pieces of stuff. Dark energy ...
2
votes
3answers
662 views

why can't the missing mass (evidence for dark matter) be matrioshka brains/dyson spheres?

i know that the claim is that nucleosynthesis models say that the observed abundance of deuterium is too high for dark matter to be baryonic, but couldn't deuterium be a waste product of ...
2
votes
1answer
100 views

Relation between $\Lambda$ and $\Omega_\Lambda$ in $\Lambda\mathrm{CDM}$

In minimal $\Lambda\mathrm{CDM}$, there is a parameter labeled $\Omega_\Lambda$, and current fits place it at around $\left( \Omega_\Lambda \sim 0.73\right)$. Meanwhile, $\Lambda$ enters the Einstein ...
2
votes
1answer
85 views

Neutrino mass as counted in Dark Matter

If I try to add up neutrino masses (let's assume 1 eV rest mass equivalent each) to count as DM, do I use the rest mass or relativistic mass?
2
votes
1answer
111 views

Dark Matter and Rotational Velocity Curves of Galaxies and Stellar Systems

The way dark matter is introduced to documentary watchers such as myself is to account for the difference between the rotational velocity of the stars in a galaxy compared to that of planets in ...
2
votes
2answers
239 views

What about the neutron stars with CMB temperature as dark matter?

Inspired by How do we know that dark matter is dark? and What is the temperature of the surface and core of a neutron star formed 12 billion years ago now equal to?
2
votes
2answers
68 views

Lagrangian point or dark matter?

We know that spiral galaxies spin in a way such that we have to assume that dark matter is responsible for the extra mass required to do so. My question is, can Lagrangian points (L1 and L2) be used ...
2
votes
2answers
190 views

Dark matter and QFT

My understanding is that the particle is a somewhat artificial notion in QFT (see: Quantum Mechanics: Myths and Facts), and that in general it is possible for a quantum field to have unstable ...
2
votes
1answer
244 views

Relativistic Mass and Dark Matter

In a question here Ron Maimon comments that "relativistic mass makes gravity, not rest mass." If so, does that mean that the faster that stars orbit the galaxy the larger the relativistic mass of the ...
2
votes
1answer
214 views

The role of dark matter in black holes and star formation

In my understanding, there exists a critical mass for which a star needs to be in order for it to collapse into a black hole. This also applies to a certain critical density of gas in order for stars ...
2
votes
1answer
46 views

Can the proportion of dark energy change?

This post generalizes the posts: - Proportion of dark matter/energy to other matters/energy at the beginning of the universe? - How do people calculate proportions of dark matter, dark energy ...
2
votes
1answer
70 views

Dark matter detection

In the detection of weakly interacting massive particles (WIMPs), which is the basis of dark matter, what is the use of the tank filled with liquid xenon? I mean, how does the releasing of photons ...
2
votes
2answers
413 views

Neutralino Dark Matter Detection

Assuming supersymmetry exists and a neutralino is stable, it's often seen as a leading dark matter candidate. What would be expected from the interaction of a neutralino and its anti-particle? Has ...
2
votes
3answers
145 views

Ability to detect pulsars

Am I correct it remembering that unless a pulsars beams plane faces earth we can not detect them. And that similarly inbetween the pulses we can't see them either? If so how does this differ from ...
2
votes
2answers
35 views

Big Bang Question

In the early Universe it it's believed that matter and anti-matter annihilated one another till there was but a remaining 1% left. In a matter/anti-matter collision, is there not an explosion of ...
2
votes
1answer
64 views

Elastic vs Inelastic vs isospin violating scattering particle physics models

I'm looking for a nice paper that explains the difference between three particle physics models for spin-independent dark matter interaction with nuclei: elastic, inelastic and isospin violating ...
2
votes
1answer
81 views

Dark energy before radiation or after?

In the cosmic history of the universe, does the dark energy comes before the radiation epoch, or only now, in the 'matter' universe (matter dominated era)? Because, we now know that like 75% of our ...
2
votes
1answer
136 views

On non-local physics

Recently I've encountered work by prof. B.V Alekseev, in which he claims that some physical problems can be easily solved if we consider non-local interactions in kinetic theory (interactions of ...
2
votes
2answers
380 views

Has Bose-Einstein theory been considered for dark matter?

Has Bose-Einstein theory been considered for dark matter? The theory would explain why no measurable radiation is emitted due to zero temperature--its lack of interaction with other matter and its ...
2
votes
0answers
90 views

Partial waves and the velocity expansion of a scattering cross section

I'm confused about the relation between the velocity expansion of a scattering cross section and the angular momentum (partial wave) expansion. For example, for dark matter annihilation, we write ...
2
votes
0answers
81 views

Remaining Potential Experimental Particle Physics Discoveries at the TeV Scale?

With the discovery of the Higgs Boson, some have been calling it the end of experimental particle physics for our generation, due to the fact that all of the particles predicted by the standard model ...
2
votes
0answers
143 views

Particle dark matter coherent scattering?

Particle dark matter coherent scattering direct searches rely on the scattering of the DM particle off a nucleus (Xe, Si, Ge, NaI etc). The wisdom is this is coherent scattering: so the rate ~atomic ...
2
votes
2answers
329 views

Is it possible for dark matter to somehow turn into regular matter?

Is it possible for dark matter to create the regular matter that we, the stars, and the galaxies are made of? The reason I'm asking this is because I have a hard time imagining how something can ...
1
vote
5answers
734 views

Why can't missing mass be photons?

After a star lives and dies, I assume virtually all of it's mass would be photons. If enough stars have already lived and died, couldn't there be enough photon energy out there to account for all the ...
1
vote
3answers
321 views

Redshift of light in dark matter

Following Edwin Hubble, it is widely believed that the universe is expanding, which is based on the red-shift of light from distant objects. Can dark matter cause light to be red-shifted and make it ...
1
vote
1answer
81 views

Could there be a correlation between the Island of Stability and dark matter?

I can only boast of my passion for science and not of any credentials. I ask because I am curious, and it is not the type of question one can easily Google! What if the key to discovering and ...
1
vote
1answer
78 views

How much of the mass of a supermassive black hole comes from dark matter?

How much of the mass of a supermassive black hole comes from dark matter? Assuming cold dark matter exists and that it doesn't bank up and get pushed away from black holes like some baryonic matter. ...
1
vote
2answers
259 views

Is cosmic background radiation dark-matter and/or dark-energy?

Dumb question alert: Is it possible that the cosmic background radiation might be the source of dark-matter and/or dark-energy? What is the mass of the background radiation in the known universe?
1
vote
1answer
73 views

Böotes Void and Dark Galxies

Wouldn't it be possible that Böotes Void, a space we generally consider to be "empty" be filled with a number of undetectable dark galaxies?
1
vote
2answers
189 views

Possibility of making dark energy equivalent with dark matter

I was curious whether it is possible to make dark energy equivalent to dark matter. Can this unification be done? If it can, why do scientists prefer to separate dark energy from dark matter?
1
vote
3answers
185 views

Can virtual particles, in particular gravitons, interfere?

Question 1. Can virtual particles, in particular gravitons, interfere? Virtual particles are created and annihilated in a distance too small and a time too short to be measured. Their existence is ...
1
vote
1answer
288 views

What exactly are super WIMPs?

I recently got confused (and slightly annoyed by the lack of technical details) when reading a popular article (authored by Jonathan Feng and Mark Trodden) introducing the concept of super WIMPs. The ...
1
vote
1answer
42 views

If MOND theory doesn't explain gravitational lensing, couldn't well placed black holes explain it?

When I first heard about star velocity as a function of its distance from the center of the galaxy and the difference between prediction and observation I immediately thought "there must be a ...
1
vote
0answers
26 views

What actually Dark energy is ? [duplicate]

I recently read an article on dark matter and I could understand this things given as follows All the ordinary matter we can find accounts for only about 4 percent of the universe. We know this by ...
1
vote
0answers
17 views

What's the evidence, if any, for some local concentration(s) of dark matter in some region(s) smaller than a galaxy?

What's the evidence, if any, for some local concentration(s) of dark matter in some region(s) smaller than a galaxy? Galactic-sized--or larger--gravitating halos seem to get all the attention. I'm ...
1
vote
0answers
29 views

How does dark matter interact with light?

Most articles I read say that dark matter are weakly interacting particles. Are there any theories on how dark matter may interact with light/electromagnetic radiation?
1
vote
2answers
41 views

Has energy in 'transit' been incorporated into missing matter calcs.?

Has energy in 'transit' been incorporated into missing matter calcs. ?It would seem that, although very small in mass, the sheer number of particles shhoting about from one end of the universe to the ...
1
vote
0answers
47 views

Has the idea of holeum been debunked?

Here is the wikipedia article. The basic idea is that the primordial density of microscopic black holes was high enough that many were able to form stable bound states before decaying through Hawking ...
1
vote
0answers
27 views

Superconducting loop as a particle detector?

Imagine that one has induced a persistent current in a superconducting loop. If a particle interacted with an electron in one of the Cooper pairs then would some decoherence and dissipation occur? I ...
1
vote
0answers
76 views

Weak gravitational lensing multispectral, multibackground correlations

My understanding of weak gravitational lensing is that it assumes random alignment distribution of galaxies in order to estimate statistical shear and convergences, which are used to estimate matter ...
1
vote
0answers
89 views

Why not “black matter” instead of “non-baryonic cold dark matter”? [closed]

I would like to know if any epistemologist or science popularizer has ever think about a better/simpler name for exotic or non-baryonic cold dark matter like black matter. That would be interesting ...
1
vote
0answers
149 views

Why is “dark matter” a more parsimonious explanation than “more normal matter than we thought”? [duplicate]

Possible Duplicate: Why isn't dark matter just matter ? The evidence usually presented in support of dark matter is larger-than-expected masses in galaxy clusters: the mass required for ...
0
votes
2answers
79 views

Could anti matter collisions be or make dark matter?

I've recently seen that space is or could be a quantum vacuum full of particles like matter and anti matter appearing and possibly colliding causing in theory the same effects that dark energy has. My ...
0
votes
1answer
37 views

When experimental search for exotic dark matter-like particles began exactly?

I am looking for information about : what was the first experiment that claimed to look specifically for non baryonic dark matter particles ; when occurred the first serious(*) reporting of an ...
0
votes
1answer
492 views

Could Dark Matter be a manifestation of tachyons tunnelling between black holes?

Among the many Dark Matter candidates, I wondered if there are any along the lines of the title. The inner horizon of a black hole, with its mass inflation, and/or the high spacetime curvature, seems ...
0
votes
1answer
50 views

Dark Matter as possible an explanation for Coronal Heating

It's my understanding that the mechanism behind Coronal Heating - why the Corona is so much hotter (> 1,000,000 K) than the surface of the Sun (6,000 K), and the mechanism by which the energy gets ...
0
votes
1answer
77 views

Why are dark matter explanations more apt to consider different mechanics than emissivity?

I've seen some treatments in the scientific popular press (podcasts) that consider the possibility that dark matter can be explained by an error (or new term) in our understanding of gravitation & ...
0
votes
1answer
54 views

Is dark matter expanding the universe, and creating the structures within it?

If dark matter repelled other dark matter, as well as regular matter(atomic or celestial), and regular matter were repelled by other regular matter "less" than by the dark matter, would not this ...
0
votes
1answer
114 views

Why the world is so deep and dark?

We live in a dark world, and the light is results of big bang. The world is really made mostly of dark matter and dark energy? Why the world is so deep and dark?
0
votes
1answer
167 views

Understanding particle's space travel

Before the discovery of dark matter, the prevailing popular understanding of Space content is that of celestial bodies (planets, stars..etc) floating in 'void' and emitting particles and waves ...