at this point in time we cant claculate the size of the universe, this is because we dont have the technology to do so and because the universe is constantly expanding as you read this.
There is no opposite for universe, but the opposite of a large area (macrocosm) would be a microcosm.
A Brain?
Everyone wonders about this at some point. The universe is beyond measure.
The observable Universe has a diameter estimated at 93 billion light-years.
Because the universe is so large, they need something like light to at least reach large amounts of distance.
The expansion of every part of our Universe was as big as our Universe -- which, if not infinitely large, is pretty big.
Chuck Norris
All objects in the universe with mass are attracted to each other by gravity, which is the large scale organizer of the universe itself.
If you counted 1 galaxy per second, it would take ~3200 years to count all 100 billion galaxies in the universe.
Probably nothing.
"Vast" simply means "very large".
The set of Pythagorean triple is three dimensional and infinitely large.