Related papers: Unitarity in Multi-Higgs Production
Using the classical recursion relations we compute scattering amplitudes in a spontaneously broken Gauge-Higgs theory into final states involving high multiplicities of massive vector bosons and Higgs bosons. These amplitudes are computed…
Calculations of $1\to N$ amplitudes in scalar field theories at very high multiplicities exhibit an extremely rapid growth with the number $N$ of final state particles. This either indicates an end of perturbative behaviour, or possibly…
We use the semiclassical formalism based on singular solutions in complex time to compute scattering rates for multiparticle production at high energies. In a weakly coupled $\lambda \phi^4$ scalar field theory in four dimensions, we…
At very high energies scattering amplitudes in a spontaneously broken gauge theory into multi-particle final states are known to grow factorially with the number of particles produced. Using simple scalar field theory models with and…
Calculations of high multiplicity Higgs amplitudes exhibit a rapid growth that may signal an end of perturbative behavior or even the need for new physics phenomena. As a step towards this problem we consider the quantum mechanical…
In a spontaneously broken gauge theory we consider (sub)-processes in which one virtual intermediate state (it can be a Higgs or a gauge field) produces many on-shell Higgses and massive vector bosons. In the kinematic regime where all…
We consider the Standard Model extended by the addition of a complex scalar singlet, with no assumptions about additional symmetries of the potential. This model provides for resonant di-Higgs production of Higgs particles with different…
We revisit perturbative unitarity in scalar field inflation with a nonminimal coupling, with Higgs inflation serving as the most prominent example. Although such models are phenomenologically successful, it is critical to examine whether or…
The scalar particle production from vacuum in the presence of electric field, on the de Sitter spacetime is studied. We use perturbation methods to define the transition amplitude. We obtain that the momentum is not conserved in this…
Recently, the problem of unitarity violation during the preheating stage of Higgs inflation with a large non-minimal coupling has been much discussed in the literature. We point out that this problem can be translated into a strong coupling…
We tackle the issue of the factorial growth in the amplitudes of multi-Higgs production at high energy by developing a phenomenological approach based on the Higgs splitting functions and Sudakov factors. We utilize the method of generating…
It has been shown recently that the amplitude of the creation of $n$ real scalar particles by one virtual boson near $n$--particle threshold exhibits exponential behavior at $n\sim1/\lambda$. We extend this result to the processes of…
Na\"ive dimensional analysis seems to suggest possible unitarity violations in the framework of the Higgs and new Higgs inflationary scenarios. These violations seem to happen around the value in which the potential energy, per given Higgs…
A recent calculation of the multi-Higgs boson production in scalar theories with spontaneous symmetry breaking has demonstrated the fast growth of the cross section with the Higgs multiplicity at sufficiently large energies, called…
We present exact tree-order amplitudes for $H^* \to n~H$, for final states containing one or two particles with non-zero three-momentum, for various interaction potentials. We show that there are potentials leading to tree amplitudes that…
We present universal formulas for particle production from gravitational inhomogeneities. In the massless limit the result is strikingly simple and completely determined by the two-point function of the energy-momentum tensor that is fixed…
Scalar field models of inflation based on a large nonminimal coupling to gravity xi, in particular, Higgs inflation, may violate unitarity at an energy scale ~ M_p / xi << M_p. In this case the model is incomplete at energy scales relevant…
In view of a recently renewed interest to production of multiple Higgs bosons the amplitude for such process at the threshold of $n$ particles is considered. An explicit calculation is done for the loop corrections to the amplitude arising…
A method to efficiently compute, in a automatic way, helicity amplitudes for arbitrary scattering processes at leading order in the Standard Model is presented. The scattering amplitude is evaluated recursively through a set of…
We calculate the contributions to the two-loop scattering amplitudes $h \to gg$, $h \to ggg$ and $h \to q \bar q g$ that arise from a modified trilinear Higgs coupling $\lambda$. Analytic expressions are obtained by performing an asymptotic…