Difference between Black Holes & Dark Matter?

Answer 1

A black hole is an object predicted by general relativity, with a gravitational field so powerful that even electromagnetic radiation (including light itself) cannot escape its pull.

A black hole is defined to be a region of space-time where escape to the outside universe is impossible. The outer boundary of this region is called the event horizon. Nothing can move from inside the event horizon to the outside, even briefly, due to the extreme gravitational field existing within the region. For the same reason, observers outside the event horizon cannot see any events which may be happening within the event horizon; thus any energy being radiated or events happening within the region are forever unable to be seen or detected from outside. Within the black hole is a singularity, an anomalous point in space-time where all matter is infinitely dense and is infinitely compressed into nothingness.



Dark matter must exist to account for the gravity that holds galaxies together. If the only matter in the universe was matter we could directly detect, galaxies would not have had enough matter to have ever formed. The galaxies we observe today would fly apart because they wouldn't have enough matter to create a strong enough gravitational force to hold themselves together. Dark matter is also responsible for amplifying small fluctuations in the Cosmic Microwave Background back in the early universe to create the large scale structure we observe in the universe today.

Answer 2

Both dark matter and black holes can't be imaged themselves, but the gravitational effects of each on other objects can be seen. Black holes are very dense dead stars, so they have a lot of mass concentrated in one spot. Dark matter is more diffuse and appears to be pretty much everywhere, so unlike black holes where you can pinpoint a certain location, dark matter can only be inferred from bigger things like galaxy and galaxy clusters. Black holes are dense, dead stars and we're pretty sure they exist. Wormholes are theoretical passages through space that we don't know exist. Wormholes would let you go somewhere; black holes would just kill you (they're not actual holes).

Answer 3

When a star died and became a supernova it will continue to expand but after that an implosion will cause that all that mass colide and colide and dissapear becoming as we know as a Black Hole, the bigger the star the strongest the implosion. we can't see a black hole ,we would see their effects among stars or planets near them., if a planet comes to on his way the hole will suck all that matter so as we know matter is energy and energy can not be destroy only trasnformated , so this "sucked" planet matter will became "dark matter" or antimatter., even do we do not see it , that does not mean it is non existent. Nothing escapes to a black hole is Gravity in is max expression, Scientist are aware that our planet is at high risk to meet a black hole of course it don't have to be near our galaxy just to affect our system, 'cause his gravity would jeopardyze our galaxy at all.

Answer 4

Black holes are stars that have collapsed under their own gravity to a density that does not permit even photons to escape. Dark matter is simply the matter in space that we can't see but we assume is there because it helps explain the balance of mass and energy that current physical theories require to explain the universe as it is.

Answer 5

There is no similarity..everything differs....
similiarty is we can't see both...

Black holes are made of fermions...
dark matter is made of some other particle(not yet detected)but it will be a boson.

Dark matter doesn't emit gamma rays..
Black holes do as GRB's

We can detect black holes but dark matter we can't...we came to know about it when there was mass difference....

Answer 6

Dark matter is a theoretical name for matters in the universe that it not accounted for yet. It's only a theoretical name, unlike black holes.

Black holes (now proven by scientists) and also seen and monitored by NASA, are created by stars losing their light and reduced to their smallest structure (atom), which creates infinite gravity that sucks everything in including light.

Black holes are sometimes static, sometimes they move around.

More info:

http://en.wikipedia.org/wiki/Dark_matter

http://en.wikipedia.org/wiki/Black_hole

Answer 7

black holes are collapsed stars with known masses (roughly)
dark matter is a theoretical idea for why there seems to be missing matter in every galaxy and solar system we observe.

Answer 8

black holes are gravity wells that suck everything including light in, dark matter is anti matter and causes 100% nuclear reaction when in contact with matter (uranium usulay only has 2%)

Answer 9

We can detect black holes. They are very massive and have very obvious gravitational effects over small distances.