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Ever since Newton and the use of mathematics in physics, physics can be defined as a discipline where nature is modeled by mathematics. One should have clear in mind what nature means and what mathematics is. Nature we know by measurements and observations. Mathematics is a self consistent discipline with axioms, theorems and statements having absolute ...


if space has an edge, there are many ways in which you can put boundary conditions. For instance, if you make it perfectly reflective, the universe will conserve energy but not linear momentum. You can also make objects disappear at the edge so no quantities are conserved. Or you can make the objects or particles to reappear at the opposite side of the ...


To understand this one shall take in quantum-mechanical approximation method namely perturbation theory into account. In perturbation theory, systems can go through intermediate virtual states which often have energies different from that of the initial and final states. This is because of time energy uncertainty principle. Consider an intermediate state ...


Usually we think of space as not having a boundary. Either because it is infinite, or because it is a compact surface (such as a three sphere). I rather think GR will not work on manifolds with boundaries. Furthermore, the concept of "nether" is a physical concept not known to me.

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