A paper first-authored by this scientist theorized that the photon number density became fixed near redshift 2 million, leading to mu-type distortion. This scientist is the first namesake of the dominant mechanism of y-type distortion, whose second-order form allows one to infer peculiar velocities from temperature fluctuations. This scientist is the second namesake of a model in which turbulence causes angular momentum transport, as encoded by the dimensionless parameter alpha. (15[2])That model of (*) viscosity-driven accretion was developed by this scientist and Nikolai Shakura. (10[1])This scientist is the first namesake (10[2])of an effect in which electrons in galaxy clusters cause inverse Compton scattering that imparts (10[3]-5[1])anisotropies on the CMB. For 10 points, what Soviet physicist co-names that effect with Yakov (10[1])Zel’dovich? ■END■ (0[3])