Questions about the source or effects of the matter that makes up 85% of the matter in the universe but appears to only interact gravitationally.

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Could dark matter be “inside-out” reality?

Where we are, and in the conventional galaxies etc. that we see, there is a whole lot of relatively uniform space but in isolated places within that space, there are pockets of concentrated "mass" ...
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2answers
164 views

Conventional matter to dark matter ratio, outside of galaxies (Bounty!)

I'm pleased to offer a bounty to attract more attention to the fantastic Astronomy site. Consider say this outstanding diagram from another question, To begin with galaxies have a typical ...
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2answers
43 views

Warm and Hot dark matter density profiles

For cold dark matter, density profiles are well known and easy to find information about - eg. NFW, Burkert, Einasto, and others. But for some reason I couldn't find explicit expressions for the ...
3
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2answers
96 views

Is time taken into account by astronomers when creating and using maps of the universe?

There's really two questions I'm asking. Firstly, when maps are produced of stars and galaxies, are they just produced as we see them now from our viewpoint? Or are they based on the motion of those ...
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1answer
108 views

What is 'Dark Fluid'?

Is this term official jargon/wording for 'Dark Matter'? If so, why include the word "Fluid" if there is supposedly no viscosity in actual space. It would be like saying 'Hey, want to go swim in my '...
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3answers
77 views

Can “dark matter” be the additional mass from the speed of the Galactic Cluster?

Considering that the Earth orbits the Sun at 100 000 km/h and that the Sun orbits the Milky Way at almost 1 000 000 km/h, could it be possible that the galactic cluster orbits some super cluster at ...
3
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2answers
274 views

Can the theory of multiuniverse explain dark matter?

If there are many universes they must have an gravity effect on each other. Since dark matter is measured through gravity but we dont know the mass behind it, isnt it possible that it comes from ...
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0answers
48 views

Does a self-gravitating gas necessarily develop turbulence?

Though we may still doubt the exact driving mechanism of turbulence in each particular case (ISM, MC, circum-BH/-stellar discs, atmospheres...), can I say that in a sphere of dark matter particles no ...
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2answers
91 views

Can dark matter decrease the Jeans length?

I am wondering if there are any models of interstellar cloud collapse out there which take dark matter into account. If dark matter has local perturbations or density fluctuations, then that may be ...
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1answer
1k views

Can dark matter be found in the shape of planets, galaxies etc.?

If dark matter has gravity just like normal matter, does that mean it can also form planets, solar systems and so on? Any answer will be appreciated.
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5answers
406 views

Could light be dark matter?

Is it possible that light itself is dark matter? I am speaking of photons (e.g. visible light, infrared, ultraviolet, etc...). I realize light is understood to be massless, but it is obvious it at ...
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1answer
50 views

Dark matter inertial mass

We know the existence of dark matter because we can test its gravitational mass (e.g. in gravitational lens) but, since we cannot see this matter, how we can be sure that it has an inertial mass, and ...
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1answer
53 views

Initially non-flat space-time makes dark matter obsolete$\dots$

After the Big Bang, dark matter clusters and build the seeds for visible matter, that then forms stars, planet, you, me, everybody... But do we really need dark matter to build cluster first. What if ...
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1answer
77 views

How does dark matter interact with black holes?

Is dark matter trapped near / in black holes, like regular matter is, or does something different happen with dark matter?
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1answer
68 views

Could dark matter assist with star formation?

This is related to the question: "Can dark matter decrease the Jeans length?" If dark matter assists in any way with star formation, shouldn't it be detectable by precisely measuring velocities in ...
3
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1answer
68 views

Is dark matter influenced by gravity of baryonic matter?

As far as I know galaxies and clusters form along so-called "galactic filaments" which are influenced by a dark matter web that organises them in to this position in the universe. So it looks like ...
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2answers
71 views

Is Higgs Boson mass equal to the missing mass of dark matter?

Sorry if this is a very lay question. I am just an armchair physicist. The Higgs Boson was just recently discovered, and it has a mass which is considerably larger than a proton. If this Higgs Boson ...
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2answers
5k views

What are the differences between matter, dark matter and antimatter?

I thought dark and anti matter were kinda the same, but after saw a video, they mention that dark matter is not antimatter but their explanation is a little fast so I got doubts. What are the ...
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0answers
34 views

Does the quantity of dark matter needed in the Milky Way to give the stars their speed compare with the speed of the Milky Way?

Dark matter was needed to give the stars in a spiral galaxy a cause of their speed. So they proposed there must be some extra dark matter in the Galaxy. The total extra mass of dark mater is quite ...
4
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1answer
194 views

Is there a strong galactic magnetic field?

My main question is: Is there a strong galactic magnetic field, perhaps driven by the supermassive black hole at the center of our galaxy? I am also wondering if this field would be strong enough to ...
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1answer
91 views

What's the relation between Einstein's Gravitational Theory and Dark Matter?

I was reading an elementary book on dark matter (in fact, a historical perspective) and there were mentioned how the scientific community react to the idea of dark matter proposed as a solution to ...
4
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1answer
49 views

Can an SMBH recycle dark matter into energy?

I just had a conceptual question, hopefully it makes for some really interesting answers. I was wondering, as most galaxies have an SMBH at their centre (see Kormandy & Richstone 1995; Richstone ...
3
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1answer
89 views

Does Dark Matter affect the motion of the Solar System?

Would dark matter have a similar effect on the Solar System as it does on the Milky Way? I'd imagine it could help hold together some of the Solar System bodies or at least affect their motion, right? ...
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1answer
63 views

TIME TRAVEL-Can it be really done? [closed]

Is it posssible for us to time travel? Is light essential factor or the dark matter and dark energy?
2
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1answer
486 views

Why aren't brown dwarfs the dark matter?

There seems to be not enough matter to account for the fact that the speed of some stars located far from the Galaxy center is almost the same speed as those stars found nearer to the center of the ...
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2answers
671 views

Two species of dark matter?

At this point in time, evidence for the existence of dark matter has accumulated in many ways: it affects galactic rotation curves plays a major role in cosmology, and the evolution of structure in ...
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3answers
386 views

Could there be dark matter black holes?

Could dark matter compress and form black holes? Since dark matter is even more abundant than normal matter, a dark matter black hole should not be rare...right?
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1answer
161 views

Does “Dark Matter” really exist?

Does dark matter really exist or is just a made-up theory in order to cover up the loopholes in the Big Bang theory, and also to explain why universe is expanding at an accelerated rate?
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1answer
63 views

Dark Matter Detection

A paper appeared at the arXiv.org (in April or May) claimed that the writers have found the gamma rays emitted by annihilation of dark matter in a satellite galaxy of the Milky Way by examining the ...
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1answer
74 views

How close are we to be able to detect and measure gravitational lensing inside the milky way?

Gravitational lensing takes advantage of statistically uniform distributions of background objects in order to infer a credible map of dark matter concentrations that isn't too noisy. If there are too ...
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1answer
210 views

Is there Dark Matter inside the Earth?

Since Dark Matter is assumed to interact gravitationally, it follows that the gravitation of massive regular matter bodies should have an effect on it. Even if it is otherwise weakly interacting with ...
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2answers
178 views

Is it certain that dark matter consists of particles? (And not just curved space)

The main idea about dark matter today seems to be supersymmetry. That there exists a set of yet undiscovered fundamental particles which (in a mathematically most convenient way) mirror the particles ...
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1answer
44 views

Mass resolution

Can someone define mass resolution in terms of cosmological simulations such as the millennium simulation? Is it just the smallest mass that a dark mater particle can have and still be detected by the ...
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1answer
77 views

Shadows of Light = Space or Dark Matter?

Perhaps my title is misleading. but here is my understanding and I'm looking for confirmation. You cannot have dark without light. The only thing faster than light is darkness (i.e. shadows) Stars ...
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2answers
114 views

Is there a connection between black holes and dark matter/energy?

Is there a spatial or gravitational relationship between black holes and dark matter/energy?
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2answers
677 views

What's the mass of the interstellar neighborhood of the Sun?

What's approximatively the mass of the interstellar neighborhood of the Sun ? (for example the neighborhood of radius 50 light-years). Remark: The mass of the observable matter should be completed ...
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2answers
228 views

Galaxy rotation curve and dark matter

I am reading "The Essential Cosmic Perspective" by Jeffrey O. Bennett, Megan O. Donahue, Nicholas Schneider, Mark Voit. In Chapter 14, it is stated that an evidence of the presence of dark matter in ...
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1answer
64 views

What are dark matter and dark energy? [closed]

I've recently read about dark matter and dark energy. But unfortunately, there were not enough answers for me. The article I read was more of a hypothesis than a real answer. So I'm asking for all the ...
2
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0answers
34 views

Deriving Dark Matter; specifically looking for a table of stellar rotational speed versus distance from center of galaxy to derive dark matter

I'm trying to find some data that I can use to derive dark matter (in a loosey-goosey sort of way, I won't be too rigorous). I'm helping a friend out with a final project for his astronomy course and ...
3
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1answer
85 views

Could dark matter be considered a medium?

Long ago, it was theorized that light had to travel through a medium, until the particle/wave duality of light was discovered. Then it changed to the idea that light can travel through the vacuum of ...
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2answers
105 views

On (minuscule) dark matter production in supernovae

It is believed that dark matter is made of particles, which interact with matter only weakly and gravitationally. One common candidate for dark matter are so called WIMPs. WIMPs, specifically, are ...
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1answer
53 views

Is there matter forming in the inflationary space?

Following the answers and the line of thinking from here Is there enough hydrogen left after a star dies so another star will have enough to light up? I was wondering if is there any possibility to ...
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2answers
1k views

What mechanism causes oscillations of the solar system's orbit about the galactic plane?

In a recent paper (news release here) Lisa Randall and Matthew Reece propose that a dark matter disk coinciding with the galactic plane together with the solar system's oscillations through the ...
5
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2answers
166 views

Has someone looked the other way?

I learned that gravity always pulls, it is always attractive. There is no antigravity, no "negative" mass. I also learned that most matter is dark, invisible. We know that because we see visible ...
6
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1answer
74 views

Density of hydrogen between galaxies

From watching a video on youtube, it states that Dark Matter is 6 times more abundant than known matter. I was wondering if it was possible to have hydrogen clouds between the universes galaxies. The ...
9
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1answer
962 views

Is it possible that all dark matter is made of rogue planets (free-floating planet)?

Is it possible that all dark matter is made of rogue planets (free-floating planet)? (and other stuff like asteroids or meteoroids)
9
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1answer
101 views

How will the recent appearance of a supernova, the closest in 27 years, help reduce the uncertainties in our measurements of dark energy?

A supernova has been recently spotted on M82, also known as the cigar galaxy. Being the closest to earth in 27 years and given the advances of technology this article proposes that: ...as the ...
2
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1answer
149 views

Could black holes be creators of dark matter?

At the tremendous forces of gravity inside a black hole, can "matter" be transformed into a more degenerate form; "dark matter" (if that truly what dark matter is)? I know the inside of a black hole ...
11
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1answer
620 views

Explaining Dark Matter and Dark Energy to layman

With my little knowledge, I know this: Dark Matter The center of a galaxy controls/attracts its objects (stars, planets, comets etc.) towards itself because of gravity. But the mass of the center of ...
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3answers
623 views

How do we know dark matter/dark energy exists?

I've never quite understood the theory behind why dark matter and dark energy exist. I know it has something to do with gravitational pull being stronger than what we calculate it SHOULD be, could ...