It's not such a stupid idea except the having to pay back the energy instantly why can't you borrow it for much longer :-)
http://en.wikipedia.org/wiki/Zero-energy_universe=> The zero-energy universe hypothesis states that the total amount of energy in the universe is exactly zero
A generic property of inflation is the balancing of the negative gravitational energy, within the inflating region, with the positive energy of the inflaton field to yield a post-inflationary universe with negligible or zero energy density.[6][7] It is this balancing of the total universal energy budget that enables the open-ended growth possible with inflation; during inflation energy flows from the gravitational field (or geometry) to the inflaton field—the total gravitational energy decreases (i.e., becomes more negative) and the total inflaton energy increases (becomes more positive). But the respective energy densities remain constant and opposite since the region is inflating. Consequently inflation explains away the otherwise curious cancellation of matter and gravitational energy on cosmological scales which is a feature of a zero-energy free-lunch universe, which is consistent with astronomical observations.
Not saying it's right but it is a valid thought :-)
