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In the conventional seesaw models of neutrino masses, leptogenesis occurs at a very high scale. Three approaches have been discussed in the literature to lower the scale of leptogenesis making them testable: mass degeneracy, hierarchy of couplings and three-body decays. We advocate yet another approach to a testable leptogenesis, whereby the decaying particles could go out of equilibrium at an accessible scale due to kinematics, although their couplings to the decay products are larger for generating a desired CP asymmetry. We demonstrate this new possibility for the testable leptogenesis in a two-Higgs doublet model where the neutrino masses originate from a one-loop diagram.

Comparisons of the positive and negative halves of the distributions of parity-odd event variables in particle-physics experimental data can provide sensitivity to sources of nonstandard parity violation. Such techniques benefit from lacking first-order dependence on simulations or theoretical models, but have hitherto lacked systematic means of enumerating all discoverable signals. To address that issue this paper seeks to construct sets of parity-odd event variables which may be proved to be able to reveal the existence of any Lorentz-invariant source of nonstandard parity violation which could be visible in data consisting of groups of real nonspace-like four-momenta exhibiting certain permutation symmetries.

The equilibrium of globular and galaxy clusters is analyzed using a gravitomagnetic (GM) model for a fluid in stationary, axially-symmetric motion. An oblique change of coordinates leads to a free-fall nonlinear force balance equation relating the GM flux function and the gravitational potential. An approximate internal solution of the force balance is obtained introducing trial functions in the form of a sedimentation equilibrium. The internal solution defines the tangential component of the GM field acting on the surface of the cluster. This GM component constitutes the boundary condition that must be used to obtain a self-consistent solution together with Gauss’ and Ampère’s laws. The complete solution is postponed for future work, but a simple application to the classic Coma Cluster problem indicates that the rotating velocity on the surface of the cluster is within the range of observed values, without introducing dark matter.