Related papers: Helicity Amplitudes for massive gravitinos in N=1 …
We present the full two-loop four-graviton amplitudes in N=4,5,6 supergravity. These results were obtained using the double-copy structure of gravity, which follows from the recently conjectured color-kinematics duality in gauge theory. The…
In this paper we evaluate the modified celestial amplitude for gravitons and gluons, as defined in arXiv:1801.10171[hep-th]. We find that the modified (tree) amplitude is finite for gravitons in Einstein gravity. The modified amplitude…
We illustrate the use of new on-shell methods, 4-dimensional unitarity cuts combined with on-shell recursions relations, by computing the A_4^{(1)}(phi,1^-,2^-,3^+,4^+) amplitude in the large top mass limit where the Higgs boson couples to…
Spin-1 resonances are naturally present in composite Higgs frameworks. We first review a model independent approach to parametrize a single additional heavy triplet and then we consider more realistic models arising in composite Higgs…
We calculate graviton multi-point amplitudes in an anti-de Sitter black brane background for higher-derivative gravity of arbitrary order in numbers of derivatives. The calculations are performed using tensor graviton modes in a particular…
In this letter we derive new expressions for tree-level graviton amplitudes in $\mathcal{N}=8$ supergravity from BCFW recursion relations combined with new types of bonus relations. These bonus relations go beyond the famous $1/z^2$…
Based on the correspondence between the N = 1 superstring compactifications with fluxes and the N = 4 gauged supergravities, we study effective N = 1 four-dimensional supergravity potentials arising from fluxes and gaugino condensates in…
The couplings that can be introduced between a massless Rarita-Schwinger field, a Pauli-Fierz field and an Abelian three-form gauge field in eleven spacetime dimensions are analyzed in the context of the deformation of the solution of the…
We use twistor inspired rules to compute the one-loop amplitude for a Higgs boson coupling to any number of negative helicity gluons in the large top mass limit.
An introduction to spin techniques in particle physics is given. Among the topics covered are: helicity formalism and its applications to the decay and scattering of spin-1/2 and spin-1 particles, techniques for evaluating helicity…
We review our recent results on dark matter from Starobinsky supergravity. In this context, a natural candidate for Cold Dark Matter is the gravitino. On the other hand, assuming the supersymmetry broken at scales much higher than the…
In this paper we use a constructive approach based on gauge invariant description of massive high spin particles for investigation of possible interactions of massive spin 2 particle. We work with general case of massive spin 2 particle…
Cachazo and Skinner have recently conjectured a new formula for the complete tree-level S-matrix of N = 8 supergravity. The formula is an integral over the moduli space of rational curves in supertwistor space, and remarkably, manifests the…
We construct the low-energy effective lagrangian for a light gravitino coupled to the minimal supersymmetric standard model under the assumption that supersymmetry breaking is communicated to the observable sector dominantly through soft…
We obtain the matter-graviton scattering amplitude in the gravitational theory of quadratic curvature, which has $R_{\mu\nu}^2$ term in the action. Unitarity bound is not satisfied because of the existence of negative norm states, while an…
We study the phenomenology of generic supergravity models in which gravity mediation naturally competes with gauge mediation as the origin of supergravity-breaking. This class of hybrid models has been recently motivated in string inspired…
In the minimal helicity-chirality formalism, we systematically construct higher-point massive amplitudes from the fundamental building blocks: the contact three-point and four-point massive amplitudes. The inclusion of four-point contact…
The manifestly SU(4)xU(1) super-Poincare invariant free-field N=2 twistor- string action for the ten-dimensional Green-Schwarz superstring is quantized using standard BRST methods. Unlike the light-cone and semi-light-cone gauge-fixed…
A compactification of 11-dimensional supergravity with two (or more) walls is considered. The whole tower of massive Kaluza-Klein modes along the fifth dimension is taken into account. With the sources on the walls, an explicit composition…
Light gravitino productions in association with a neutralino (selectron) in e^+e^- (e^-\gamma) collisions are restudied in a scenario that the lightest supersymmetric particle is a gravitino and the produced neutralino (selectron) promptly…