Radiation Problem in Transplanckian Scattering

We investigate hard radiation emission in small-angle transplanckian scattering. We show how to reduce this problem to a quantum field theory computation in a classical background (gravitational shock wave). In momentum space, the formalism is similar to the flat-space light cone perturbation theory, with shock wave crossing vertices added. In the impact parameter representation, the radiating particle splits into a multi-particle virtual state, whose wavefunction is then multiplied by individual eikonal factors. As a phenomenological application, we study QCD radiation in transplanckian collisions of TeV-scale gravity models. We derive the distribution of initial state radiation gluons, and find a suppression at large transverse momenta with respect to the standard QCD result. This is due to rescattering events, in which the quark and the emitted gluon scatter coherently. Interestingly, the suppression factor depends on the number of extra dimensions and provides a new experimental handle to measure this number. We evaluate the leading-log corrections to partonic cross-sections due to the initial state radiation, and prove that they can be absorbed into the hadronic PDF. The factorization scale should then be chosen in agreement with an earlier proposal of Emparan, Masip, and Rattazzi. In the future, our methods can be applied to the gravitational radiation in transplanckian scattering, where they can go beyond the existing approaches limited to the soft radiation case.Comment: 41 pp, v2: minor changes and added refs, conforms with published versio

Descent Relations in Cubic Superstring Field Theory

The descent relations between string field theory (SFT) vertices are characteristic relations of the operator formulation of SFT and they provide self-consistency of this theory. The descent relations and in the NS fermionic string field theory in the kappa and discrete bases are established. Different regularizations and schemes of calculations are considered and relations between them are discussed.Comment: Replaced to JHEP styl

Rationalization of Polymer Composite Materials Processing by Improving Production Efficiency

AbstractEconomic efficiency is one of the main criteria in the design of technological parts processing. To determine this criterion we have identified the main production expenses, including the cost of the cutting tool, the cost of its training, workers’ wages, energy and materials costs. Cost values were obtained for different process parameters. The parameters of the process were the cutting conditions, structural and technological characteristics of cutting tools, as well as the properties of the material being processed. On the basis of the calculated data and the results of conducted experimental studies rationalization of process parameters was performed. It is possible to increase the economic efficiency of the machining of polymeric composite materials by the example of milling fiberglass. The research found that the dependence of the resulted expenses of the cutting conditions has an extreme character, where the minimum point shifted upward cutting conditions by increasing production. According to the research recommendations for the purpose of cutting conditions were developed, ensuring minimal production expenses