Yuriy Mishchenko Papers:
Bakker B., DeWitt M., Ji C.-R., Mishchenko Y. (2005) "Restoring the equivalence between the light-front and manifestly covariant formalisms.", Physical Review D 72, 076005

This work studies the phenomenon that certain diagrams in perturbative quantum field theory (QFT), nonvanishing when written covariantly, vanish in Light Front reference frame. The problem is linked, in this paper, to two types of limits, not performed carefully typically when going to Light Front reference frame. Outer arc integration limit is one of them, whereas when reducing covariant integrands by integrating out one of the momentum variables using Cauchy residues, the infinite arc closing the contour is often dismissed, even in certain cases it gives contribution to the integral, as we show. The second type of limits is the case where particular cingular points on the integration axis of the remaining integrand give a finite-constant contribution. Properly taking care of these limits restore the equivalence between LF and covariant frames without need for any ad-hoc regularization prescriptions. Full text