What does it mean to have parallel worlds?

Question

I was searching Strange Coincidences and it say"Parallel Worlds"

Answer 1

When you get into advanced physics, you'll learn that there are more dimensions that just the 4 that you're familiar with. The first is a line, the second is an infinitely flat plane, the 3rd basically an axis that is perpendicular to the plane. (3D) like a box or sphere.  The 4th is time.  We are 3 dimensional and we are aging so the first 4 are easy.  

For a parallel world, you'll have to imagine another universe that occupies the same space at the same time as ours but exists in a 5th dimension.  It's pretty complicated and very theoretical.

Answer 2

It means that somewhere in the universe there is a life going on just like this one. Research Eistein & antimatter to learn more.

There is a theory that proves this is true.

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Answer 3

Wellll.... *generally*, in science fiction (and in some theories), a "Parallel world" refers to the possibility of alternate dimensions - dimensions that might contain an Earth, maybe another You, but one that we have no way of detecting, and likewise - neither would they.  

Answer 4

The previous poster is wrong. There is no theory that proves this is true. Some theories of the Universe require it, but it's by no means certain that those theories are correct.

Anyway, parallel worlds are Universes that may or may not be like our own, or differ in some details. In many sci-fi stories, they're called other dimensions, or parallel dimensions. In theory there could be an infinite number of you; perhaps one turned left when you went right. One choked on cereal when you had toast. One married a movie star; one is a beggar. One was crushed by a UFO landing on 'you'. Any possible thing that could happen to you has happened, or is happening, to another you. But to all of them, 'you' are the one in a parallel world, and they live in the real world. Who's to say which is right?