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We present two simple analytical methods for computing the gravity wavecontribution to the cosmic background radiation (CBR) anisotropy ininflationary models; one method uses a time-dependent transfer function, theother method uses an approximate gravity-wave mode function which is a simplecombination of the lowest order spherical Bessel functions. We compare the CBRanisotropy tensor multipole spectrum computed using our methods with theprevious result of the highly accurate numerical method, the ``Boltzmann''method. Our time-dependent transfer function is more accurate than thetime-independent transfer function found by Turner, White, and Lidsey; however,we find that the transfer function method is only good for $l \la 120$. Usingour approximate gravity-wave mode function, we obtain much better accuracy; thetensor multipole spectrum we find differs by less than 2\% for $l \la 50$, lessthan 10\% for $l \la 120$, and less than 20\% for $l \leq 300$ from the``Boltzmann'' result. Our approximate graviton mode function should be quiteuseful in studying tensor perturbations from inflationary models.Comment: The Boltzmann curve is updated, which leads to small corrections.  LaTeX, 15 pages, 6 figures available via anonymous ftp at  ftp://fnas08.fnal.gov/pub/Personal/ywang

Simple analytical methods for computing the gravity-wave contribution to the cosmic background radiation anisotropy