Texture - Induced Microwave
نویسندگان
چکیده
We use numerical simulations to calculate the cosmic microwave background anisotropy induced by the evolution of a global texture eld, with special emphasis on individual textures. Both spherically symmetric and general conngurations are analysed, and in the latter case we consider eld conngurations which exhibit unwinding events and also ones which do not. We compare the results given by evolving the eld numerically under both the expanded core (XCORE) and non-linear sigma model (NLSM) approximations with the analytic predictions of the NLSM exact solution for a spherically symmetric self-similar (SSSS) unwinding. We nd that the random unwinding connguration spots' typical peak height is 60{75% and angular size typically only 10% of those of the SSSS unwinding, and that random conngurations without an unwinding event nonetheless may generate indistinguishable hot and cold spots. A brief comparison is made with other work.
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