Question

ok a doubt'
that is there any theory discovered for dark matter ..if no then can it be detected by theories of gravity..?​

Answer 1

Answer:

Dark matter is just what its name implies; it is matter (or mass) in the universe that we cannot see directly using any of our telescopes. Our telescopes see not only visible radiation (constituting the spectrum of colors that our own eyes can detect), but other types of radiation as well.

Hence we still do not have any direct evidence for dark matter, let alone have some idea as to its physical properties or its non-gravitational interactions with the Standard Model particle.

Hope it helps