DARK MATTER, BLACK HOLES & WORMHOLE :

In our sky, we observe a number of things --- stars, planets, galaxies, asteroids, comets, meteors, and much more. All these stuff is a very small fraction of what actually exists. The visible things of the Universe comprises only about a sixth of  Universe's mass. Where is the remaining mass of our universe?

Scientists believe that there must be more things in our Universe than we see through our naked eye because the strange substance has gravity which holds the parts of the Universe together, particularly galaxies. This Unknown substance does not emit any radiation, as a result of which scientists called it Dark Matter. Many scientists believe that about 95% of the Universe's mass is comprised by Dark Matter.

WHAT IS A BLACK HOLE?

Lets first understand "how a black hole is formed?". A black hole is formed when a very huge, dying star is collapsed. The gravity created by the black hole overpowers any forces including light. A black hole does not emit any light because of which its presence is detected with the help of a radio astronomy equipment. A black hole owns an extremely strong gravitational pull from which nothing can escape within a certain distance, not even light. The largest black hole on record weighs as much as 40 billion suns and it is orbited by an another small black hole.

WHAT IS A WORMHOLE?

Wormhole is an idea of modern astrophysics, according to which, a wormhole is short lived portal, lasting for a very short period of time joining two black holes at different locations. Most scientists believe that wormholes could connect two different points in the universe in the present day or may be at different times. According to the wormhole theory, matter falling into a black hole at one point should emerge through a "white hole"(reverse of a black hole at the other end. So far, we do not have any evidence of existence of wormholes.