The Stability Filter and What ALPHA and AEGIS Should Find
Every single confirmed particle physics process ever observed produces matter and antimatter in exactly equal amounts, without exception. And yet the observable universe is overwhelmingly, one-sidedly matter, with no confirmed evidence anywhere at all of large-scale, naturally occurring antimatter domains of any kind. This mismatch, the matter-antimatter asymmetry, is one of the deepest unresolved puzzles in modern physics, and the standard model's own explanation for it, a specific kind of CP violation, has never been measured at anywhere near the magnitude required to actually account for the asymmetry observed. This piece develops this framework's alternative account directly, and follows it through to specific, currently testable predictions.
The scale of the standard model's own shortfall here deserves to be stated plainly and directly, since it's often glossed over quickly in popular treatments of the problem. The specific form of CP violation confirmed within the Standard Model, first observed in the decay of neutral kaons back in 1964 and since confirmed in several other particle systems as well, is real and precisely measured. But calculations based on that confirmed mechanism produce a predicted matter-antimatter asymmetry many orders of magnitude smaller than what's actually needed to explain why the universe contains the amount of matter it currently does, instead of having long ago annihilated down to almost nothing but leftover radiation. This gap is not a minor rounding discrepancy, and it shouldn't be treated as one. It's one of the most-cited open problems in the entire Standard Model, and decades of dedicated searching for additional sources of CP violation, beyond the confirmed kaon and B-meson systems, have not yet managed to close it.
The Stability Filter, Not a Separate Process
Instead of treating the matter-antimatter asymmetry as a wholly separate physical process requiring its own dedicated explanation, layered awkwardly on top of ordinary particle formation, this framework instead locates the asymmetry's true origin at the same stability-selection stage already responsible for proton formation itself, discussed in careful detail in Paper Sixteen. At the moment particles first condense from the underlying substrate, only a specific, stable excitation fraction persists at macroscopic scale; unstable configurations, whatever their initial relative abundance, simply don't survive long enough to accumulate into any observable structures at all. Under this account, the same stability filter that determines which three-core topology wins out over competing configurations also determines which of matter's and antimatter's respective condensation pathways ends up dominating the macroscopic population, removing entirely the need for a wholly separate, additional asymmetry-generating mechanism of the kind the standard model has searched for, without success, across several decades now.
Why This Account Doesn't Just Restate the Problem
A fair objection is worth addressing directly and honestly: doesn't locating the asymmetry in a stability filter just relocate the mystery, instead of actually resolving it? The answer this framework offers is that the stability filter itself isn't a new, separately invented mechanism, introduced specifically to explain the asymmetry after the fact. It's the same filter already established, independently, as the mechanism selecting a three-core topology over competing alternatives in ordinary matter formation, examined in full mathematical detail in the two preceding pieces of this framework. The asymmetry, under this account, isn't a separate phenomenon needing its own separate explanation. It's a direct, predictable consequence of a mechanism this framework was already fully committed to, for entirely independent reasons, well before the antimatter question was ever specifically addressed at all.
It's worth being precise about what kind of theoretical economy this actually represents, since it's the central methodological virtue this piece is claiming for itself. The standard model's own treatment of the matter-antimatter asymmetry requires physics beyond what's already confirmed, some additional CP-violating process, of a magnitude not yet observed anywhere, operating at some early cosmological epoch not yet directly probed by any experiment. This framework's account requires no comparable addition. It applies a mechanism already derived, for unrelated reasons, in the process of explaining ordinary proton formation, and simply asks what that same mechanism implies when applied to the earlier, more general stage of quark stability-selection. If that mechanism turns out to be correct, the matter-antimatter asymmetry stops being a separate open problem requiring its own dedicated new physics, and becomes instead a straightforward corollary of physics this framework needed to establish anyway.
Two Specific, Testable Predictions
This account develops directly into two specific, falsifiable predictions, both directly relevant to active experimental programmes running right now, today, at CERN, not at some distant, unspecified future date. The first: antihydrogen, an atom built from an antiproton and a positron instead of a proton and an electron, should fall under gravity exactly as ordinary hydrogen does, to the full limits of achievable measurement precision, with no anomalous gravitational behaviour of any kind. This prediction is directly testable by the ALPHA and AEGIS collaborations at CERN, both purpose-built to measure precisely this question, whether antimatter responds to gravity identically to ordinary matter or shows some detectable deviation.
The second of the two predictions: macroscopic, stable antimatter domains should not form under ordinary physical conditions anywhere in the universe, a direct consequence of the same stability filter that favours matter's specific condensation pathway over antimatter's. This prediction is consistent with, and offers a specific mechanistic account for, the complete absence of any confirmed observational evidence for large-scale antimatter regions anywhere in the observable universe, an absence that's long been treated as simply an empirical fact requiring its own separate explanation, instead of a direct, predictable consequence of the same stability mechanism already at work in ordinary matter formation.
It's also worth noting directly how this second prediction connects to an entirely separate, independent observational programme, one not mentioned elsewhere in this piece: searches for antimatter signatures in cosmic ray data, and searches for the specific gamma ray signature that large-scale matter-antimatter annihilation at cosmic boundaries would produce if such boundaries existed anywhere nearby. Decades of dedicated searches using instruments like the Fermi Gamma-ray Space Telescope have found no such signature anywhere in the observable universe, a null result fully consistent with this framework's second prediction, though not, on its own, sufficient to confirm the specific stability-filter mechanism proposed here over other possible explanations for the same absence.
What Would Actually Falsify This
Both of these two predictions are stated deliberately in a form that leaves this account genuinely and meaningfully exposed to being proven wrong. If the ALPHA or AEGIS collaborations, or any successor experiment with comparable or better precision, were to find that antihydrogen falls under gravity in a way that measurably differs from ordinary hydrogen, even by a small amount, that result would directly contradict this framework's account of the stability filter and would require the mechanism proposed here to be substantially revised or abandoned. Similarly, confirmed observational evidence of a genuine, large-scale, naturally occurring antimatter domain anywhere in the universe, something current cosmic ray and gamma ray observations have found no credible evidence for so far, would directly undermine the second prediction. Neither possible outcome is being pre-emptively explained away here in advance; both are stated plainly as genuine tests this framework could actually fail.
It's worth noting the current, real-world, up-to-date experimental status of the first of these two predictions directly and specifically here, since it isn't purely a matter reserved for some distant, hypothetical future date. The ALPHA collaboration published a landmark result in Nature in 2023, directly measuring the gravitational behaviour of antihydrogen for the first time with meaningful precision, and found it consistent with ordinary gravitational attraction, in the same direction and of comparable magnitude to hydrogen's behaviour, though the measurement's precision at that stage was not yet tight enough to rule out small deviations at the level this framework's account would eventually need to be tested against. Later runs, and the AEGIS collaboration's own parallel measurement programme, are expected to substantially tighten that precision over the coming years, which is precisely the kind of incrementally improving test this piece's first prediction is built to be checked against as the data accumulates, instead of a single decisive experiment expected to settle the matter all at once.
Why the CERN Connection Matters Beyond This One Piece
This is one of the clearer examples, across this entire collection, of a theoretical claim connecting directly to an active, ongoing, independently funded experimental programme that has no institutional stake in this framework's success or failure. The ALPHA and AEGIS collaborations were not built to test this specific framework; they exist to answer a fundamental question about antimatter that matters regardless of which theoretical account, if any, turns out to explain it correctly. That independence is exactly what makes this piece's two predictions valuable as a genuine test instead of a self-serving one: the data that will eventually confirm or contradict them is being collected by researchers with an entirely separate motivation, using instruments built for a broader scientific purpose than checking any single alternative cosmological framework, which is precisely the kind of evidentiary independence a genuinely falsifiable prediction should aim for.
All DOIs linked below.