Through the Wormhole: How Does the Universe Work?With the help of massive machines called particle accelerators, scientists studied the subatomic realm and made discoveries about the forces that operate at that level. But the search for a comprehensive explanation still continues.

In particular, physicists have sought to find a way to reconcile Einstein's model of space-time, which seems to work best when applied to big objects like stars and galaxies, and the theory of quantum mechanics, which offers an explanation of electromagnetic and nuclear forces that makes sense of reality at the tiniest level.

In recent years, some have proposed a novel solution called string theory, in which tiny particles are loops that vibrate like violin strings in a multidimensional space.

In the mathematical calculations that make up string theory, gravitation is a byproduct of the process. While string theory offers a possible solution to the ultimate question of the ages, there's a hitch: Scientists have not yet found a way to test the theory experimentally to prove that it's more than just an elegant idea. List of all episodes here: Through The Wormhole.

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