Question

what is the tiniest substance in universe​

Answer 1

Answer:

The electron is, as far as we know, one of the fundamental, indivisible building blocks of the universe. It was the first Standard Model particle ever discovered. Electrons are bound to an atom's nucleus by electromagnetism.

Answer 2

$\mapsto$ As far as we can tell, quarks can't be broken down into smaller components, making them the smallest things we know of. In fact, they're so small that scientists aren't sure they even have a size: they could be immeasurably small!