2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/147262We present a theoretical calculation of the variance $ΔC_l$ of the CMB anisotropy power spectrum $\langle C_l\rangle$ caused by gravitational waves based on quantum field theory in an inflationary cosmology.8 pages, written in RevTeX. An error in the calculation was found and corrected. The conclusion of the paper changedAstrophysicsHigh Energy Physics - Phenomenologytext