An curved arrow pointing right. Caltech theoretical physicist Sean Carroll stopped by Business Insider to talk about string theory, parallel universes, and other exciting topics he discusses in ...

An curved arrow pointing right. CalTech theoretical physicist Sean Carroll stopped by BI to talk about string theory, parallel universes, and other exciting topics he discusses in his new book ...

Like stretch marks left on skin that expanded too quickly or cracks embedded in freezing ice, cosmic strings are artifacts of what the universe looked like in the moments before it rapidly changed ...

That would be compelling evidence for both string theory and parallel universes, and it would help explain why gravity seems to be so much weaker than the other fundamental forces. Still ...

This suggests that string theory may indeed be an inevitable description of the universe, even as direct experimental verification remains out of reach. “A bootstrap is a mathematical construction in ...

according to string theory, exist in parallel dimensional membranes—bump into one another, the impact sets off an astronomical Big Bang that generates a universe-worth of elements in the fiery ...

String theory has its supporters and its gainsayers among theoretical physicists. Even advocates admit that the theory could be entirely wrong (though naturally they don't think it is).

Parallel universes crop up in two places in physical theories. One is in our conception of inflation, the theory of the ...

In order for that to work, string theory has to make one more radical assumption. That instead of living in a universe with three dimensions of space and one of time, we live in one with either 9 ...