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Can dark matter form planets and dark matter life?

by silvercats
Tags: dark, form, life, matter, planets
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silvercats
#1
Jan21-13, 10:15 PM
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Can dark matter form planets and dark matter life?
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Drakkith
#2
Jan21-13, 11:58 PM
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Probably not. It appears that dark matter does not interact through any of the 4 fundamental forces except for gravity. What happens is that dark matter falls in towards high mass areas and simply passes through all normal matter AND itself before slowing under gravity and falling in again. Without a way to lose the kinetic energy it gains from the fall it simply repeats this falling in process over and over again.
Bobbywhy
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Jan22-13, 03:25 AM
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Quote Quote by Drakkith View Post
Probably not. It appears that dark matter does not interact through any of the 4 fundamental forces except for gravity. What happens is that dark matter falls in towards high mass areas and simply passes through all normal matter AND itself before slowing under gravity and falling in again. Without a way to lose the kinetic energy it gains from the fall it simply repeats this falling in process over and over again.
Drakkith, I have been reading this post to try to visualize the dynamic process you’ve described. Would the dark matter constituting the “halo” surrounding a spiral galaxy actually be falling towards the high mass area (galaxy center), pass through and then come to a stop on the far side, only to return again to the other side? Continual motion of all this dark matter presumably would drag inertial space (Lense-Thirring) along with it. Is there some evidence for this motion?

Cheers,
Bobbywhy

manojr
#4
Jan22-13, 03:45 AM
P: 62
Can dark matter form planets and dark matter life?

Quote Quote by Bobbywhy View Post
Would the dark matter constituting the “halo” surrounding a spiral galaxy actually be falling towards the high mass area (galaxy center), pass through and then come to a stop on the far side, only to return again to the other side?
Cheers,
Bobbywhy

Any local concentration of dark matter and matter may result in such movement similar to simple harmonic motion. But dark matter must be everywhere around center of galaxy, and dark matter is estimated to significantly more than matter, such motion may not take place. If it does happen, at the time when all dark matter is crossing over the central region, the total gravitational force from central region will spike up and attract other matter to collapse in center.
manojr
#5
Jan22-13, 03:54 AM
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Quote Quote by Drakkith View Post
Probably not. It appears that dark matter does not interact through any of the 4 fundamental forces except for gravity. What happens is that dark matter falls in towards high mass areas and simply passes through all normal matter AND itself before slowing under gravity and falling in again. Without a way to lose the kinetic energy it gains from the fall it simply repeats this falling in process over and over again.
Can dark matter pass through a black hole as well? Or is it trapped inside even horizon?
Drakkith
#6
Jan22-13, 04:05 AM
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Quote Quote by Bobbywhy View Post
Drakkith, I have been reading this post to try to visualize the dynamic process you’ve described. Would the dark matter constituting the “halo” surrounding a spiral galaxy actually be falling towards the high mass area (galaxy center), pass through and then come to a stop on the far side, only to return again to the other side? Continual motion of all this dark matter presumably would drag inertial space (Lense-Thirring) along with it. Is there some evidence for this motion?

Cheers,
Bobbywhy
My understanding is that this is what basically happens. I don't know any details at all though.

Quote Quote by manojr View Post
Can dark matter pass through a black hole as well? Or is it trapped inside even horizon?
I believe it would be trapped inside. But remember that the central supermassive black hole in our galaxy is VERY VERY small compared to the size of the galaxy. Dark matter could easily fall in a great many times and never pass through it.
julcab12
#7
Jan22-13, 07:01 AM
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There is speculation that certain constraints (adiabatic contraction) on primordial black holes as dark matter candidates from star formation. Considering, "If" the DM consists partly of primordial black holes (PBHs), they will be trapped together with the rest of the DM and will be finally inherited by a star compact remnant(neutron or a white dwarf).

According to what i've read. Assuming it did happen. Dark matter heating alone is incapable of rendering a planet habitable in the vicinity of the solar system, low-emissivity super-Earths in the neighborhoods of the centers of dwarf galaxies and the Milky Way may be able to sustain liquid water thanks to this mechanism. This result should be approached with caution as it is strongly dependent on the precise nature of as-yet-undetected dark matter. We "might envision" cloud-shrouded worlds wandering interstellar space with life thriving on dark matter annihilation. Even if incapable of rendering planets habitable on its own, dark matter heating 'might' abet volcanism and plate tectonics, helping create an environment more conducive to the emergence of life as we know it. I'm not sure of it goes beyond that but it's plausible. At least in theory.

http://prd.aps.org/abstract/PRD/v87/i2/e023507
http://map.gsfc.nasa.gov/universe/uni_matter.html
julcab12
#8
Jan22-13, 07:41 AM
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Quote Quote by manojr View Post
Can dark matter pass through a black hole as well? Or is it trapped inside even horizon?
Light is not absorbed or emitted by dark matter (observational). However, Dark matter is affected/interacting by/with gravity. We can assume that dark matter in baryonic matter form ('undetectable by its emitted radiation, but whose presence can be inferred from gravitational effects on visible matter') do fall into a blackhole but uncertain (trapped or whatever it leads).
silvercats
#9
Jan22-13, 08:31 AM
P: 54
no no. Is it possible there are matter like dark matter things? Dark matter planets ,people etc.... separately. Maybe they also detected our matter(dark matter to them) weakly interacting with their dark matter(matter to them). :D ?possible? yes another world
Sayajin
#10
Jan22-13, 08:48 AM
P: 16
I am not expert in this but if we assume that DM is made of some kind of particles that do not interact with EM weak or strong forces the only possibility for them to make complex systems like some strange lifeforms and thing like that is to interact through some unknown fundamental force which does not affect our "known"(from SM of partical physics) particles.
No one has observed other kinds of fundamental interactions between particles. Infact if the interactions does not affect our known particles then there might be no way to prove or know that they exist.

If we assume that the 4 fundamental forces are the only that can exist in the universe then there is no way for dark matter to form complex emergent systems.
The only way for this to happen is if there are some very strange laws of physics that we don't know and they don't affect our ordinary "matter".

Nobody can give answer for this questions since we don't even know what DM is in the first place.
Ibix
#11
Jan22-13, 08:54 AM
P: 378
Quote Quote by silvercats View Post
no no. Is it possible there are matter like dark matter things? Dark matter planets ,people etc.... separately. Maybe they also detected our matter(dark matter to them) weakly interacting with their dark matter(matter to them). :D ?possible? yes another world
Paraphrasing Drakkith's first post:

Not in our current understanding. Dark matter only appears to interact through gravity. Everything 'interesting' that normal matter does, like forming atoms and molecules and complex structures like stars, planets and life, needs strong, weak, and electromagnetic interactions, which dark matter does not do.

We cannot, strictly speaking, rule out the possibility of complex dark matter structures because we know very little about it. But there is no evidence and no theory to suggest that it's possible. That's as close to an outright 'no' as scientists will get.
Chronos
#12
Jan22-13, 11:11 AM
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Dark matter is not an important food source for black holes. See http://curious.astro.cornell.edu/que...php?number=358 for discussion.
manojr
#13
Jan22-13, 10:24 PM
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Quote Quote by Chronos View Post
Dark matter is not an important food source for black holes. See http://curious.astro.cornell.edu/que...php?number=358 for discussion.
According to this discussion, matter falls in central region because of loss of angular momentum after interaction among the particles, but dark matter does not interact so there is no loss of angular momentum.
Angular momentum is result of particles interacting with each other (Bouncing particles cancel off the momentum except in direction of angular movement). Therefore, dark matter must not have angular momentum in first place. The reason dark matter does not fall in because it is everywhere (equally distributed within galaxy) and it does not interact with itself.
Drakkith
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Jan22-13, 11:24 PM
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Quote Quote by manojr View Post
According to this discussion, matter falls in central region because of loss of angular momentum after interaction among the particles, but dark matter does not interact so there is no loss of angular momentum.
Angular momentum is result of particles interacting with each other (Bouncing particles cancel off the momentum except in direction of angular movement). Therefore, dark matter must not have angular momentum in first place. The reason dark matter does not fall in because it is everywhere (equally distributed within galaxy) and it does not interact with itself.
Angular momentum is not the result of particles interacting with each other. Consider that fundamental particles already have intrinsic angular momentum in their spin. And I don't think dark matter is equally distributed everywhere. To my knowledge most of it exists as a spherical "halo" surrounding our galaxy, with a smaller amount falling inward towards the center before passing through the galaxy and gradually slowing once it is back in the halo region.


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