String theory, also dubbed as "the theory of everything" has been able to unify all four fundamental forces. The most revolutionary finding of the string theory is that our 3D world is not the entire universe. It is actually embedded in a ten dimensional space, analogous to a TV screen (2D) embedded in a house (3D). Theologians have long suspected that God could live in a higher dimensional space. Now that the string theory has provided evidence for the existence of a higher dimensional space, the theory could also unify religion with science.

The string theory was originally developed to unify the gravitational force with other three fundamental forces where the quantum theory works very well. According to quantum theory, every particle has a wave nature which is the essential feature that the string theory has adopted. In the string theory, all elementary particles are considered as the vibrational waves of a "string", which is extremely short, only about 10^-33 centimeter.

The string which produces all kinds of elementary particles is analogous to a guitar string whose vibrations produce various music notes. Similarly, different vibrational waves of a particle string give rise to different elementary particles. The vibrational waves depend on the endpoints of a string. The particle string can be either "open" (with two endpoints, like a guitar string) or "closed" (no endpoints, like a circle). In contrast to a guitar string whose endpoints are attached on the instrument, the endpoints of a particle string are attached (restricted) on a "brane" (as in membrane), which is a sub-universe with up to nine dimensions of space. Since its endpoints are restricted, the open-string particle cannot escape from the brane. However, the closed-string particle can go anywhere in the bulk universe because it has no endpoints to be restricted. Mathematically, different endpoints have different boundary conditions and the vibrational waves obtained by solving the wave equation will also be different.

The physical properties of elementary particles in our 3D world are known from experiments. The vibrational waves of a particle string can be obtained by solving the wave equation in the string theory with proper boundary conditions (corresponding to endpoints). It has been found that, in order to match observed particle properties with theoretical vibrational waves, the particle string must vibrate in an 11-dimension universe (one dimension of time plus ten dimensions of space). Thus, the whole universe should have ten dimensions of space, instead of three dimensions that we used to think.

The string theory further shows that all elementary particles - except the graviton (gravitational wave) - are open strings with endpoints attached on our 3D brane. Therefore, all matter in our world is trapped in the 3D space. There is no way for our matter to escape from the 3D brane into the 10D space. The ONLY thing that can go to the 10D space is the graviton which is a closed-string particle. If the soul can go to Heaven (10D space), it must be an entity composed of gravitational waves only.