Decoupling of gravity on non-susy D$p$ branes

Understand

We study the graviton scattering in the background of non-susy D$p$ branes of type II string theories consisting of a metric, a dilaton and a $(p+1)$ form gauge field.

• We show numerically that in these backgrounds graviton experiences a scattering potential which takes the form of an infinite barrier in the low energy (near brane) limit for $p\leq 5$ and therefore is never able to reach the branes.
• This shows, contrary to what is known in the literature, that gravity indeed decouples from the non-susy D$p$ branes for $p \leq 5$.
• For non-susy D6 brane, gravity couples as there is no such barrier for the potential.