In the linearized theory of gravity coupled to the electromagnetic field, we calculate the cross sections of two processes in which both the gravitational and electromagnetic interactions play a role. Those processes, in which a graviton is produced in the final state, are: (a) the photoproduction of graviton off electrons, and (b) the production of a photon and a graviton from e-e pair annihil...

The graviton localized on the 3-brane is examined in Randall-Sundrum braneworld scenario from the viewpoint of one-dimensional singular quantum mechanics. For the Randall-Sundrum single brane scenario the one-parameter family of the fixed-energy amplitude is explicitly computed where the free parameter ξ parametrizes the various boundary conditions at the brane. The general criterion for the lo...

At present no theory of a massive graviton is known that is consistent with experiments at both long and short distances. The problem is that consistency with long distance experiments requires the graviton mass to be very small. Such a small graviton mass however implies an ultraviolet cutoff for the theory at length scales far larger than the millimeter scale at which gravity has already been...

Recently, tree-level recursion relations for scattering amplitudes of gluons in YangMills theory have been derived. In this note we propose a generalization of the recursion relations to tree-level scattering amplitudes of gravitons. We use the relations to derive new simple formulae for all amplitudes up to six gravitons. In particular, we present an explicit formula for the six graviton non-M...

The interactions of gravitons with matter are calculated in parallel with the familiar photon case. It is shown that graviton scattering amplitudes can be factorized into a product of familiar electromagnetic forms, and cross sections for various reactions are straightforwardly evaluated using helicity methods.

There exist consistent low energy effective field theories describing gravity in the Higgs phase that allow the coexistence of massive gravitons and the conventional 1/r potential of gravity. In an effort to constrain the value of the graviton mass in these theories, we study the tensor contribution to the CMB temperature anisotropy and polarization spectra in the presence of a non-vanishing gr...

We study the flavor-changing quark-graviton vertex that is induced at the one-loop level when gravitational interactions are coupled to the Standard Model. Due to the conservation of the energy-momentum tensor the corresponding form factors turn out to be finite and gauge-invariant. Analytical expressions of the form factors are provided at the leading order in the external masses. We show that...

It is shown that screening the background of super-strong interacting gravitons creates for any pair of bodies as an attraction force as well an repulsion force due to pressure of gravitons. For single gravitons, these forces are approximately balanced, but each of them is much bigger than a force of Newtonian attraction. If single gravitons are pairing, a body attraction force due to pressure ...

I discuss the scattering of a graviton (or a dilaton, or an anti-symmetric tensor) on two parallel static Dp-branes. The graviton belongs to a type II string in 10D.