The Baryon Asymmetry Problem

The baryon asymmetry of the universe — the fact that we observe approximately one extra baryon for every billion photons, with essentially no antibaryon complement — is one of the deepest unsolved problems in physics. The Standard Model contains sources of CP violation in the CKM quark mixing matrix and potentially in the PMNS neutrino mixing matrix, but these are insufficient by many orders of magnitude to generate the observed η ~ 6 × 10⁻¹⁰ from a symmetric initial state. Proposed extensions including GUT baryogenesis, leptogenesis via heavy neutrino decay, electroweak baryogenesis through a first-order phase transition, and Affleck-Dine baryogenesis all require physics beyond the Standard Model that has not been experimentally confirmed. The Sakharov conditions must all be satisfied, yet no Standard Model or near-Standard Model scenario satisfies them at the required level, making this the most concrete example of BSM physics demanded by cosmological observation.

Successive Collision Theory resolves the baryon asymmetry problem by recognizing that our observable universe does not need to generate its baryon number from a symmetric state — it inherited its baryon number from the pre-existing matter in the two colliding spacetime pockets. In eternal infinite spacetime, the question of why there is more matter than antimatter in our patch transforms into a question about the matter content of the pre-existing pockets, which themselves formed from prior collision events in the eternal universe. The pre-existing pockets contained matter — stars, gas, compact objects — that had been matter-dominated since long before our collision epoch. The local baryon asymmetry we observe is the density of that pre-existing matter thermalized into our debris field, not a dynamically generated deviation from zero. The value of η reflects the ratio of pre-existing baryon number to the photon entropy generated by the collision kinetic energy, both of which are set by the collision parameters.

This resolution is logically complete without invoking any new symmetry-breaking mechanism or new particles, because it shifts the origin of the asymmetry to the eternal prior history of the universe rather than to a process within our observable patch. In eternal infinite spacetime with nonzero matter density, every collision event produces a debris field with some baryon number inherited from the pre-existing pockets. The specific value η ~ 6 × 10⁻¹⁰ is determined by the mass-energy budget of the colliding pockets divided by the kinetic energy converted to radiation — a ratio that is calculable in principle from the collision parameters. The Sakharov conditions are not required within our patch because baryogenesis is not occurring here; the matter was already here before our Big Bang event. The eternal universe as a whole must satisfy conditions for matter-antimatter asymmetry to persist in pockets over cosmic timescales, and the stability of baryons over the lifetimes of the eternal universe's prior epochs provides this without requiring fine-tuned symmetry breaking.