A distinctive signature of extra-dimensions: The enhanced open string pair production

In analogy to the Schwinger pair production in QED, there exists also the so-called open string pair production for a system of two Dp branes, placed parallel at a separation, with at least one brane carrying a worldvolume electric flux, in Type II string theories. There is however no such pair production if an isolated Dp brane carrying an electric flux is considered. The produced open strings are directly related to the brane separation, therefore to the extra-dimensions if taken from the viewpoint of a brane observer. This pair production can be greatly enhanced if one Dp brane carries also a magnetic flux. The largest pair production rate occurs for $p = 3$, i.e., the D3 brane system, with the same applied fluxes. A detection of this pair production by the brane observer as the charged particle/anti-charged particle pair one shall signal the existence of extra-dimensions and therefore provides a potential means to test the underlying string theories.