A contribution to the discussion of the matter-antimatter asymmetry problem

K. Urbanowski

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arXiv · hep-ph/9905279

A contribution to the discussion of the matter-antimatter asymmetry problem

K. Urbanowski

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Abstract

Using a more accurate effective Hamiltonian governing the time evolution in the particle-antiparticle subspace of states than the one obtained within the Lee-Oehme--Yang approach we show that in the case of particles created at the initial instant t = 0 only the masses of a stable particle and its antiparticle are the same at all t > 0 in a CPT invariant system, whereas the masses of an unstable particle and its antiparticle are equal only at t = 0 and then during their time evolution they become slightly different for times t >> 0 if CP symmetry is violated but CPT symmetry holds. This property is used to show that if the baryon number B is not conserved then the asymmetry between numbers of unstable baryons and antibaryons can arise in a CPT invariant system at t >> 0 even in the thermal equilibrium state of this system.

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K. Urbanowski. 1999-05-10. A contribution to the discussion of the matter-antimatter asymmetry problem. https://arxiv.org/abs/hep-ph/9905279

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