This might be the most decisive result of all.
When two black holes merge, there's no matter involved. Black holes are pure spacetime — mass without substance. When two neutron stars merge, there's abundant nuclear matter — the densest material in the universe, capable of forming jets, shocks, and magnetic dynamos.
Every conventional theory of cosmic ray acceleration requires matter. Jets need baryons to carry energy. Shocks need material to compress. Magnetic dynamos need plasma to anchor field lines.
So if cosmic rays come from matter-based processes, black hole mergers shouldn't produce them.
Binary Black Hole
Binary Neutron Star
Both show statistically identical cosmic ray correlation
The Statistical Test
The analysis compared cosmic ray correlations between binary black hole (BBH) events and binary neutron star (BNS) events. If matter were required, BBH correlations should be weak or absent while BNS correlations should be strong.
A p-value of 0.63 means there's no statistically significant difference between the two populations. They're indistinguishable. Black hole mergers correlate with cosmic rays just as strongly as neutron star mergers.
What This Rules Out
❌ Excluded Models
- Post-merger jets — require baryonic matter from neutron stars
- Magnetar wind acceleration — requires rapidly-rotating NS with B ~ 10¹⁵ G
- Kilonova shock acceleration — requires baryon-rich ejecta (r-process elements)
- Any matter-dependent mechanism — BBH systems have no matter to work with
This includes the prominent model by Farrar (2025), which specifically proposed binary neutron star mergers as UHECR sources through post-merger jet acceleration. That model predicts strong BNS correlation and weak/absent BBH correlation — the opposite of what's observed.
What Could Explain This?
If the correlation doesn't depend on matter, it must depend on something that both black holes and neutron stars have in common.
The answer: gravity.
Both BBH and BNS systems warp spacetime. Both create gravitational waves
during inspiral. Both cause spacetime curvature to oscillate with increasing
frequency as they spiral together. The only difference is matter content —
and that difference doesn't affect the correlation.
This points directly to a mechanism that couples to spacetime geometry rather than matter: the Selective Transient Field (STF), which extracts energy from the rate of change of spacetime curvature. Black hole binaries and neutron star binaries of similar mass create similar spacetime dynamics — and produce similar cosmic ray signals.
The Implications
Matter independence is perhaps the strongest single piece of evidence for a new acceleration mechanism. It's not a statistical fluctuation (p = 0.63 is a clear null result for difference). It's not a selection effect (BBH events far outnumber BNS events in the sample). It's a fundamental property of the correlation itself.
Whatever accelerates cosmic rays cares about mass and orbital dynamics, not about whether that mass is locked in a black hole or distributed through neutron star matter.
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