arXiv subjects
Publications and source records attributed to R. F. Alvarez-Estrada.
We study the time evolution of decaying particles in renormalizable models of Relativistic Quantum Field Theory. Significant differences between the latter and Non Relativistic Quantum Mechanics are found -in particular, the Zeno effect seems to be absent in such RQFT models. Conventional renormalization yields finite time behavior in some cases but fails to produce finite survival probabilities in others.
We analyze the finite temperature (T) extension of the Wess-Zumino- Witten functional, discussed in a previous work, to one loop in chiral perturbation theory. As a phenomenological application, we calculate finite temperature corrections to the amplitude of the $π^0$ decay into two photons. This calculation is performed in three limits : i)$T/M_π<<1$, ii)the chiral limit at finite T and iii)$T/M_π>>1$ ($M_π$ being the pion mass). The $T$-corrections tend to vanish in the chiral limit, where only the kaon contribution remains (although it is exponentially suppressed).
We discuss the finite temperature extension of the anomalous Wess-Zumino -Witten lagrangian. The finite temperature S^1\times S^3 compactification makes a structure in disconnected sectors, corresponding to different baryon numbers appear naturally. The consistency of the anomalous functional is proved for arbitrary baryon number configurations. The anomalous behavior of the functional is shown to be consistent with the absence of finite temperature corrections to chiral anomalies in QCD, for each baryon number sector.