Anchored Causality Theory

Quantum mechanics describes a wave that spreads and interferes; a detector records a particle at one place and time. Anchored Causality Theory (ACT) accounts for both: the electron is a stable wave-mode structure of one composite field, never a particle on a path. A detector’s bath of photons and atoms keeps a record that tells the alternatives apart, say the two lobes of a wave behind two slits. The record is released, beyond recall, when nothing the system will actually undergo can restore interference. One alternative becomes an event: a mark in the one actual history. No observer is needed; Schrödinger evolution is never modified.

Four thought experiments, each performed in the laboratory, carry the argument. An unread lossy slab removes the fringes; a tunable coupling sets their fading rate; a reversible filter sorts the field’s components, producing no event; and single marks build fringes with no path recorded, a particle pattern once a path record is released. For an event of ACT’s kind, eraser and recovery experiments exclude every earlier moment tested; release is the earliest allowed.

ACT changes no quantum prediction and adds one commitment: one history of released records is actual. No event leaves two marks: proved where the bath returns no record, assumed beyond. Given refinable records, two requirements force Born weights: a record’s chance here is unchanged by whether records are made elsewhere and continuous in the wave. A covariant release criterion is open. The wave is what exists; the particle is what happens.

Read the preprint · PDF, 42 pages

Also at Zenodo, the same file · version history · Keywords: measurement problem; quantum events; decoherence; quantum Brownian motion; interpretations of quantum mechanics; wave–particle duality

What the paper covers

1. The ontology in one page
2. The Rock: remove the observer, and the record remains — as an article
3. Three principles
4. The event law: what, when, which
5. What is derived, and what is postulated
6. Four experiments, told as thought experiments — the Evidence page
7. The formal backbone
8. Bell, Wigner’s friend, and the single history
9. Relation to the other interpretations
10. Scope and open problems
11. Conclusion

Four appendices carry the proofs the paper rests on: why the weights are Born’s; records, release and exclusivity; the event law; the selection theorem.

Citing the flagship

@misc{Sonderegger2026ACT,
  author    = {Sonderegger, Kelly},
  title     = {Anchored Causality Theory: A Record-History
               Ontology for Open Quantum Systems},
  year      = {2026},
  note      = {Preprint, version 3.6},
  publisher = {Zenodo},
  doi       = {10.5281/zenodo.23811463},
  url       = {https://doi.org/10.5281/zenodo.23811463}
}

The DOI above always resolves to the newest version of the paper. Version 3.6 alone is doi:10.5281/zenodo.23811464. The paper is a preprint, submitted for journal publication; the journal reference will be added here when it exists.