Groupoidification is a form of categorification in which vector spaces are replaced by groupoids and linear operators are replaced by spans of groupoids. We introduce this idea with a detailed exposition of ‘degroupoidification’: a systematic process that turns groupoids and spans into vector spaces and linear operators. Then we present three applications of groupoidification. The first is to F...

The problem of restoring Froissart bound to the BFKL-Pomeron is studied in an extended leading-log approximation of QCD. We consider parton-parton scattering amplitude and show that the sum of all Feynman-diagram contributions can be written in an eikonal form. In this form dynamics is determined by the phase shift, and subleading-logs of all orders needed to restore the Froissart bound are aut...

A long-standing question in high energy physics has been the origin of the phenomenon of CP violation. CP violation was first observed in the decay KL → π+π− [1]. Effects have subsequently been found in KL → π0π0 [2], the charge asymmetry of KL → e±π∓ν (Ke3) [3] and KL → μ±π∓ν (Kμ3) [4], KL → π+π−γ [5] and most recently in KL → ππee [6]. All of these effects can be explained by applying a singl...

We have shown a new scenario of successful leptogenesis with one $L$ violating coupling and relative Majorana phase playing the role $CP$ violation. This is in contrast to usual consideration Feynman diagram at least two couplings. considered $R$-parity Minimal Supersymmetric Standard Model (MSSM) for TeV scale. also consistent generating light neutrino mass if asymmetry generated through semil...

A simple algorithm is presented to decompose any 1-loop amplitude for scattering processes of the class 2 fermions→ 4 fermions into a fixed number of gauge-invariant form factors. The structure of the amplitude is simpler than in the conventional approaches and its numerical evaluation is made faster. The algorithm can be efficiently applied also to amplitudes with several thousands of Feynman ...

The multi-particle production at high energy neutrinonucleon collisions are investigated through the analysis of the data of the experiment CERN-WA-025 at neutrino energy less than 260GeV and the experiments FNAL-616 and FNAL-701 at energy range 120-250 GeV. The general features of these experiments are used as base to build a hypothetical model that views the reaction by a Feynman diagram of t...

We develop a new representation for the integrals associated with Feynman diagrams. This leads directly to a novel method for the numerical evaluation of these integrals, which avoids the use of Monte Carlo techniques. Our approach is based on based on the theory of generalized sinc (sin(x)/x) functions, from which we derive an approximation to the propagator that is expressed as an infinite su...

In this work we present experimental and calculated two-dimensional electronic spectra for a 5,15-bisalkynyl porphyrin chromophore. The lowest energy electronic Qy transition couples mainly to a single 380 cm(-1) vibrational mode. The two-dimensional electronic spectra reveal diagonal and cross peaks which oscillate as a function of population time. We analyze both the amplitude and phase distr...

A C-program DIANA (DIagram ANAlyser) for the automation of Feynman diagram evaluations is presented. Recent high precision experiments require, on the side of the theory, high-precision calculations resulting in the evaluation of higher loop diagrams in the Standart Model (SM). For specific processes thousands of multiloop Feynman diagrams do contribute, and it turns out to be impossible to per...

We perform the quenched lattice QCD analysis on the nuclear force (baryon-baryon interactions). We employ 203 ×24 lattice at β = 5.7 (a ≃ 0.19 fm) with the standard gauge action and the Wilson quark action with the hopping parameters κ = 0.1600,0.1625,0.1650, and generate about 200 gauge configurations. We measure the temporal correlators of the two-baryon system which consists of heavy-light-l...