DOES DARK MATTER REALLY EXIST

 1.)DARK MATTER

Dark matter can refer to any substance which interacts predominantly via gravity with visible matter (e.g., stars and planets). Hence in principle it need not be composed of a new type of fundamental particle but could, at least in part, be made up of standard baryonic matter, such as protons or neutrons.

.What will happen if dark matter and matter meet ?

As it wouldn't interact with matter, it would simply pass through the solid Earth as easily as if it were empty space. Remarkably, the dark matter particles that once made you up don't lose any energy as they pass through the Earth.

What is reason that Universe is expanding?

According to Scientists DARK MATTER IS THE ONLY REASON FOR UNIVERSE EXPANDING.