2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/185654We study $n$-point functions at finite temperature in the closed time path formalism. With the help of two basic column vectors and their dual partners we derive a compact decomposition of the time-ordered $n$-point functions with $2^n$ components in terms of $2^{n-1} -1$ independent retarded/advanced $n$-point functions. This representation greatly simplifies calculations in the real-time formalism.Revtex, 14pages, no figureHigh Energy Physics - TheoryHigh Energy Physics - Phenomenologytext