Related papers: Quantized tension: Stringy amplitudes with Regge p…
In this Thesis we address the issue of consistent higher-spin interactions taking String Theory as a "theoretical laboratory". We thus arrive at a simple expression encompassing all three-point amplitudes for states belonging to the first…
Constraints on the t-dependence of the hadronic scattering amplitude at asymptotic energies are derived by considering the exchange of the Pomeron, as a Regge pole, between off-shell gluons. Covariant reggeization ensures pure spin alpha…
We review some recent results on phenomenological approaches to strong interactions inspired in gauge/string duality. In particular, we discuss how such models lead to very good estimates for hadronic masses.
There are two cases where QCD string is described by an effective theory of long strings: the static potential and meson scattering amplitudes in the Regge regime. I show how the former can be solved in the mean-field approximation,…
We argue that the evolution of coloured partons into colour-singlet hadrons has approximate factorization into an extended parton-shower phase and a colour-singlet resonance--pole phase. The amplitude for the conversion of colour connected…
We utilize a novel method for the partial-wave unitarity recently suggested in [1] to analyse the hypergeometric Coon amplitude. In this approach we use a new type of harmonic numbers as a basis. Owing to the properties of the harmonic…
We overview symmetries of string scattering amplitudes in the high energy limits of both the fixed angle or Gross regime (GR) and the fixed momentum transfer or Regge regime (RR). We calculated high energy string scattering amplitudes (SSA)…
We calculate high energy massive string scattering amplitudes of open bosonic string in the Regge regime (RR). We found that the number of high energy amplitudes for each fixed mass level in the RR is much more numerous than that of Gross…
The Coon amplitude is the unique solution to duality constraints with logarithmic Regge trajectories. A striking feature of this solution is that it interpolates between the Veneziano amplitude and a scalar particle amplitude. However, an…
Our results on obtaining the Regge trajectory of a resonance from its pole in a scattering process and from analytic constraints in the complex angular momentum plane are presented. The method, suited for resonances that dominate an elastic…
We explicitly compute the Compton amplitude for the scattering of a photon and a (massless) ``electron/positron'' at tree level and one loop, in a four-dimensional fermionic heterotic string model. We comment on the relationship between the…
String theory provides a compact integral expression for the tree-level scattering amplitude of an arbitrary number of light strings. We focus on amplitudes involving a few tachyons and many photons, with a special choice of polarizations…
We review high energy symmetries of string theory at both the fixed angle or Gross regime (GR) and the fixed momentum transfer or Regge regime (RR). We calculated in details high energy string scattering amplitudes at arbitrary mass levels…
We briefly discuss the soft behavior of scattering amplitudes both in string and quantum field theory. In particular we show a general argument about the validity of soft theorems for open superstring amplitudes and list some of our recent…
Heavy quark transport coefficients in a strongly coupled Quark-Gluon Plasma can be evaluated using a gauge/string duality and lattice QCD. Via this duality, one can argue that for low momenta the drag coefficient for heavy quarks is…
The stochastic model of classical system of particles (partons), which dynamics includes random walk in plane as well as processes of death, splitting, annihilation and fusion of partons, is considered. A set of equations for multiparticle…
The Parke-Taylor multigluon amplitudes are examined in the multi-Regge kinematics, which assumes strong rapidity ordering of the produced gluons, and are used to compute the $n$-gluon production cross section and the gluon-gluon total cross…
We extend the study of scattering amplitudes presented in ``The LHC String Hunter's Companion'' to the case of five-point processes that may reveal the signals of low mass strings at the LHC and are potentially useful for detailed…
In this work, we study the Regge-like spectra of excited singly heavy mesons by proposing a general Regge-like mass relations in which the slope ratio $\alpha ^{\prime }/\beta ^{\prime }$ between the radial and angular-momentum Regge…
The high-energy factorization of gauge theory scattering amplitudes in terms of universal impact factors and a Reggeized exchange in the $t$-channel, corresponding to a Regge pole in the angular momentum plane, is know to conflict with the…