Related papers: Constraints on extra-dimensional theories from vir…
We live in a four dimensional world. But the idea of unification of fundamental interactions lead us to higher dimensional theories. Recently a new theory with extra dimensions has emerged, where only gravity propagates in the extra…
Massive gravity in the weak field limit is described by the Fierz-Pauli theory with 5 degrees of freedom in four dimensions. In this theory, we calculate the gravitomagnetic effects (potential energy) between two point-like, spinning…
Models involving large extra spatial dimension(s) have interesting predictions on lepton flavor violating processes. We consider some 5D models which are related to neutrino mass generation or address the fermion masses hierarchy problem.…
The graviton exchange diagram for the correlation function of arbitrary scalar operators is evaluated in anti-de Sitter space, AdS(d+1). This enables us to complete the computation of the 4-point amplitudes of dilaton and axion fields in…
We address the issue of whether extra dimensions could have an infinite volume and yet reproduce the effects of observable four-dimensional gravity on a brane. There is no normalizable zero-mode graviton in this case, nevertheless correct…
We use unitarity and analyticity of scattering amplitudes to constrain fermionic operators in the standard model effective field theory. For four-fermion operators at mass dimension 8, we scatter flavor superpositions in fixed standard…
We study the effective interactions of the fermionic, scalar and vector dark matter (DM) with leptons and neutral electroweak gauge Bosons induced by the higher dimensional effective twist-2 tensor operators. We constrain these…
In this paper we work in perturbative quantum gravity and we introduce a new effective model for gravity. Expanding the Einstein-Hilbert Lagrangian in graviton field powers we have an infinite number of terms. In this paper we study the…
We study the effective interactions of external electromagnetic fields induced by fluctuations of virtual particles in the vacuum of quantum electrodynamics. Our main focus is on these interactions at two-loop order. We discuss in detail…
We develop an effective field theory to describe the coupling of non-thermal quantum black holes to particles such as those of the Standard Model. The effective Lagrangian is determined by imposing that the production cross section of a…
It has recently been suggested that exotic quantum gravity effects could lead to large vacuum fluctuations, potentially observable with realistic detectors. Experiments are currently being built to search for these signals. Here we analyze…
We attempt to build systematically the low-energy effective Lagrangian for the Einstein--Cartan formulation of gravity theory that generally includes the torsion field. We list all invariant action terms in certain given order; some of the…
Recently Randjbar-Daemi and Shaposhnikov put forward a 4-dimensional effective QED coming from a Nielsen-Olesen vortex solution of the abelian Higgs model with fermions coupled to gravity in D=6. However, exploring possible physical…
The presence of extra dimensions can be probed in high energy collisions via the production or exchange of gravitons. The former corresponds to signatures with missing energy while the latter corresponds to modifications of the final state…
We investigate forces induced by the exchange of two light neutrinos between Standard Model (SM) fermions in the presence of effective operators parametrising physics beyond the SM. We first set up a general framework in which we derive the…
We study the question of a modification of the running gauge coupling of Yang-Mills theories due to quantum gravitational effects in a compact large extra dimensional brane world scenario with a low energy quantum gravity scale. The ADD…
Using a three-dimensional formalism that includes relativistic kinematics, the effects of negative-energy states, approximate boosts of the two-body system, and current conservation, we calculate the electromagnetic form factors of the…
We present measurements of the ep->ep pi^0 cross section extracted at two values of four-momentum transfer Q^2=1.9 GeV^2 and Q^2=2.3 GeV^2 at Jefferson Lab Hall A. The kinematic range allows to study the evolution of the extracted hadronic…
Standard Model singlet neutrinos propagating in extra dimensions induce small Dirac neutrino masses. While it seems rather unlikely that their Kaluza-Klein excitations directly participate in the observed neutrino oscillations, their…
In this paper we study both projective and non-projective constraints on four-dimensional gravitational effective fields theories implied from unitarity, causality and crossing, assuming perturbative UV completions in $M_{\rm pl}$. We…