Dipole Modulation in Tensor Modes: Signatures in CMB Polarization

In this work we consider a dipole asymmetry in tensor modes and study the effects of this asymmetry on the angular power spectra of CMB. We derive analytical expressions for the $C_{l}^{TT}$ and $C_{l}^{BB}$ in the presence of such dipole modulation in tensor modes for $l<100$. We also discuss on the amplitude of modulation term and show that the $C_{l}^{BB}$ is considerably modified due to this term.Comment: 12 pages, 5 figure

Rheological properties of a dilute suspension of self-propelled particles

With a detail microscopic model for a self-propelled swimmer, we derive the rheological properties of a dilute suspension of such particles at small Peclet numbers. It is shown that, in addition to the Einstein's like contribution to the effective viscosity, that is proportional to the volume fraction of the swimmers, a contribution due to the activity of self-propelled particles influences the viscosity. As a result of the activity of swimmers, the effective viscosity would be a lower (higher) than the viscosity of the suspending medium when the particles are pushers (pullers). Such activity dependent contribution, will also results to a non-Newtonian behavior of the suspension in the form of normal stress differences