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تسجيل مستخدم جديدThe gravitational polarization tensor of thermal $lambdaphi^4$ theory
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The low-momentum structure of the gravitational polarization tensor of an ultrarelativistic plasma of scalar particles with $lambdaphi^4$ interactions is evaluated in a two-loop calculation up to and including order $lambda^{3/2}$. This turns out to require an improved perturbation theory which resums a local thermal mass term as well as nonlocal hard-thermal-loop vertices of scalar and gravitational fields.
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