Does dark matter fall into a black hole, and create radiation

[DarkMatterHol]

Does dark matter fall into a black hole, and create radiation as it falls in like normal matter? If not, why not? If so, can we use this to detect it directly?

[Vanadium 50]

Yes, and no. It falls in, but it does not create radiation - it's dark, i.e. does not interact electromagnetically.

[DarkMatterHol]

Thank you for the reply Vanadium 50.

Does that mean that dark matter is neutral in the way neutrons and others are?

I guess the preliminary question should be - would neutrons emit radiation when they fall into a black hole?

[cjl]

Yes, and no. It falls in, but it does not create radiation - it's dark, i.e. does not interact electromagnetically.

As far as I know, we haven't established what it is, so we can't state what its properties are.

Several of the hypothesized types of dark matter would quite visibly radiate when falling into a black hole.

[Vanadium 50]

It is known that Dark Matter is electrically neutral.

I don't believe that any serious dark matter candidate (serious = matches the existing data) would radiate substantially. For example, MACHOs would radiate, but BBN and CMBR exclude them from being a substantial fraction of the dark matter.

[geoffleonard]

before i post i will make it clear to ZapperZ since he hates me, that THIS IS NOT AN ANSWER JUST A SUGGESTION! I AM NOT SAYING I KNOW EVERYTHING!

Before you can find an answer to whether it emits radiation when entering a black hole, you must first know the composition of the dark matter, but, as mentioned before, if it is 'Dark' matter then no radiation will be generated. However could a huge mass -> energy conversion not occur as soon as the dark matter touches the black hole, due to its density or would it not react in this way? I truly do not know. i would like an answer or some possible educated guess maybe ?

thank you :)

[universe11]

You have to understand first what black hole is looking at Planck limits.

[ibysaiyan]

Thank you for the reply Vanadium 50.

Does that mean that dark matter is neutral in the way neutrons and others are?

I guess the preliminary question should be - would neutrons emit radiation when they fall into a black hole?

From what I can recall some of the hypothesis shows that D.M influences the rotational speed of galaxies and so on implying "gravity" being meddled.Where observed > expected.Oh by the way your question doesn't fit how could we see radiation if everything is known to sucked in the E.H and with time dilation wouldn't it make our observation a bit harder?
~ibysaiyan

[Chronos]

The radiation emitted by ordinary matter falling into a black hole is caused by collisions with other infalling matter. Given dark matter is essentially collisionless, it cannot radiate via this mechanism.

[IlluminKnotty]

Dark Matter wouldn't create "normal" radiation. What if the Dark Matter fell in in massive amounts, would it create Dark Energy spurting out in the BiPolar Jets? Perhaps this is the source of increased Dark Energy in the Universe?!!?. It seems likely that much more Dark Matter falls into Black Holes than "Conventional Matter" does.

I must admit, my thoughts on this are based on the Romanticism/Poetry of it all. Chalk it up as a SighPhy Idea.

[Chronos]

Dark matter and dark energy are unrelated until otherwise demonstrated. The term 'dark' is purely arbitrary.

[Vanadium 50]

This is Physics Forums. You might be looking for Poetry Forums. Up two flights and down the hall.

[phinds]

This is Physics Forums. You might be looking for Poetry Forums. Up two flights and down the hall.

Actually, I think it's in a different building entirely, way on the other side of campus.

[Polyrhythmic]

Does dark matter fall into a black hole, and create radiation as it falls in like normal matter? If not, why not? If so, can we use this to detect it directly?

What kind of radiation are we talking about? Assuming that it is just ordinary matter with the handicap that it can't be seen due to a lack of electromagnetic radiation, why would it behave any different than normal matter?
Anyways, to my knowledge, anything about the nature of dark matter is speculation so far, so no definite answers can be given.