  The null detection of the QED Schwinger pair production so far could imply a
possibility regarding if the usual QED vacuum picture is a complete one. In
this paper, we address this possibility by taking our own (1 + 3)-dimensional
world as a D3 brane in Type IIB superstring theory and by considering an
analogous open string pair production process. There is a sharp distinction
between this stringy pair production and the Schwinger pair production from the
braneworld view and as such the future positive or negative detection of either
can falsify if our own world can be indeed taken as a D3 brane. The
implications of this are also discussed.
