Transport Coefficients in Large N f Gauge Theory : Testing Hard Thermal Loops
نویسنده
چکیده
We compute shear viscosity and flavor diffusion coefficients for ultra-relativistic gauge theory with many fermionic species, Nf≫1, to leading order in 1/Nf . The calculation is performed both at leading order in the effective coupling strength gNf , using the Hard Thermal Loop (HTL) approximation, and completely to all orders in gNf . This constitutes a nontrivial test of how well the HTL approximation works. We find that in this context, the HTL approximation works well wherever the renormalization point sensitivity of the leading order HTL result is small.
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تاریخ انتشار 2001