  Acoustic analogues of Kerr black hole in plasmas are considered, by taking
for granted the existence of acoustic ion waves in plasmas. An effective black
holes (BH) in curved Riemannian spacetime in a random walk plasmas is endowed
with a naked singularity, when plasmas are in the lowest diffusion mode. The
plasma particle diffusion is encoded in the effective metric. The diffusive
solution has a horizon when the plasma flow reaches the sound velocity in the
medium and a shock wave is obtained inside the slab. The sonic black hole
curved Riemannian metric is also found in terms of particle number density in
plasmas. The sonic BH singularity is found at the center of the plasma
diffusive slab from the study of the Ricci curvature scalar for constant
diffusion coefficient. It is suggested and shown that the Hawking temperature
is proportional to the plasma Kelvin temperature through diffusion coefficient
dependence to this temperature. Therefore Unruh sonic or dumb BH is shown to
have a relation between Hawking and plasma diffusive temperatures. BH
evaporation is analogous to the diffusive phenomena in plasmas, since in both
cases Hawking temperature is inversely proportional to mass. It is shown that
Hawking analogue temperature of a plasma torus is
$T_{H}(torus)\approx{10^{-4}K}$ which is much higher than the gravitational
Hawking temperature of a one solar mass BH, ${T_{H}}^{GR}\approx{10^{-8}K}$,
but still very small for being detectable in plasma laboratories.

General Relativity and Quantum Cosmology