What is dark matter and dark energy?

Question

anonymous · Answer

hi,where have you heard this words?they're in modern physics and a little confusing.but if u want i'll explain you ;)

anonymous · Answer

The rest of the universe appears to be made of a mysterious, invisible substance called dark matter (25 percent) and a force that repels gravity known as dark energy (70 percent). Scientists have not yet observed dark matter directly.

somy · Answer

@Astrophysics your topic ❤

anonymous · Answer

yes @TreDay0514 outlined it...and i just add that is may be possible that dark energy could be blackholes ...

anonymous · Answer

@PFEH.1999 

dark energy could be black holes? .. m sorry.. but that makes no sense to me :P

dark energy is the repelling force that is making the space stretch and expand.. and the expansion is accelerating

blackhole on the other hand produces immense gravity and tries to pull in together.. so clearly blackholes cannot be related to dark energy.. unless i am missing something :D

anonymous · Answer

oh sry!!! yes....i meant dark matter ;) sry ... i'm tired :D

anonymous · Answer

i don't think so 
we can calculate the mass of a blackhole.. it can be estimated by finding the speed of companion stars orbiting the blackholes.. 
and so we make a rough estimate of the number of blackholes, and number of stars
and so make an estimate the mass of the universe

and THAT mass does not account for the OBSERVED mass .. so there is clearly something more than that.. (more than blackholes)... 
that is what dark matter is supposed to be

no one knows what dark matter is..

anonymous · Answer

Thus there is no Answer for it. Thanks for all your support.

anonymous · Answer

yes and i only said it COULD be...

anonymous · Answer

you're welcome ;)

anonymous · Answer

@TryDay0514 helped you alot

anonymous · Answer

@PFEH.1999 

yea yea.. i was just saying why it COULD not be :D :D.. no offence lol!

astrophysics · Answer

Well we really don't know exactly what they are, but we know of it's effects, so basically these are just place holder names and don't let them confuse you.

Dark Matter - is the excessive gravity that holds the galaxies together, about 4x the gravity as the galaxy, yeah it's crazy.

Dark Energy - Is causing the expansion of the universe, be careful here, it isn't expanding any celestial object, just cause "space" to stretch and pushing galaxies away from each other. 

We can go a bit more in detail but I think this is what you were really looking for, we don't know much about these honestly, and if someone tells you they know, they're probably wrong lol or hiding it from the rest of the world.