References

EnterCalculus

N. Cheung. The Enter Calculus: A Linear Quantum Lambda Calculus with an Operational Characterization of Measurement. Frontiers in Physics, volume 14, 2026. doi:\ 10.3389/fphy.2026.1954943. Accepted-article record; accepted 28 September 2026. The publisher listed the final formatted version as forthcoming at the bibliographic check on 10 October 2026. https://www.frontiersin.org/journals/physics/articles/10.3389/fphy.2026.1954943/abstract.

SelingerValiron

P. Selinger and B. Valiron. A lambda calculus for quantum computation with classical control. Mathematical Structures in Computer Science, 16(3):527–552, 2006. doi:\ 10.1017/S0960129506005238.

Gleason

A. M. Gleason. Measures on the closed subspaces of a Hilbert space. Journal of Mathematics and Mechanics, 6(4):885–893, 1957. doi:\ 10.1512/iumj.1957.6.56050.

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W. H. Zurek. Environment-assisted invariance, entanglement, and probabilities in quantum physics. Physical Review Letters, 90:120404, 2003. doi:\ 10.1103/PhysRevLett.90.120404.

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M. Schlosshauer and A. Fine. On Zurek's derivation of the Born rule. Foundations of Physics, 35:197–213, 2005. doi:\ 10.1007/s10701-004-1941-6.

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K. A. Kirkpatrick. Translation of G. Lüders' “Über die Zustandsänderung durch den Meßprozeß”. Annalen der Physik, 15(9):663–670, 2006. English translation and discussion of Lüders' original projective state-change paper. doi:\ 10.1002/andp.200610207. arXiv:\ -ph/0403007.

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CompanionRegistry

N. Cheung. Enter Calculus Companion. Registered-manuscript index and source-record interface. https://enter.grok.me/. Registry consulted 10 October 2026. Individual manuscript versions cited below are unpublished records; the supplied excerpts are not independently machine-verified.

CheungEn03A

N. Cheung. En03-A, 03-A.tex, version 1. Undated registered manuscript, Enter Calculus Companion. Source locators: :enter, :recording, :nondestructive, :pullback, :obstruction, and :locality. https://enter.grok.me/.

CheungEn02B

N. Cheung. En02-B, 02-B-v1.tex, version 1. Undated registered manuscript, Enter Calculus Companion. Source locators: :B1, :moduleclass, and :separation. https://enter.grok.me/.

CheungPsy02B

N. Cheung. Psy02-B, 02-B-v2.tex, version 2. Undated registered manuscript, Enter Calculus Companion. Source locator: :process, complete-process equality and testing obstruction. https://enter.grok.me/.

CheungHawk01A

N. Cheung. Hawk01-A, 01-A.tex, version 1. Undated registered manuscript, Enter Calculus Companion. Source locator: :completion, conserving completions with identical late radiation. https://enter.grok.me/.

CheungHawk01B

N. Cheung. Hawk01-B, 01-B.tex, version 1. Undated registered manuscript, Enter Calculus Companion. Source locator: :number, exact number-record recovery obstruction. https://enter.grok.me/.

CheungHawk02A

N. Cheung. Hawk02-A, 02-A.tex, version 1. Undated registered manuscript, Enter Calculus Companion. Source locators: :spectrum and the conditional physical acceptance interface :physical. https://enter.grok.me/.

CheungEm03C

N. Cheung. Em03-C, 03-C-v1.tex, version 1. Undated registered manuscript, Enter Calculus Companion. Source section: “Open physical bridges: not additional release claims”, including the exterior/interior and horizon-smoothness boundaries. https://enter.grok.me/.

CheungEm03E

N. Cheung. Em03-E, 03-E-v1.tex, version 1. Undated registered manuscript, Enter Calculus Companion. Source locator: :recovery, exact recovery analysis for its declared finite transfer model. https://enter.grok.me/.

CheungXIVI

N. Cheung. XIV-I, -I.tex, version 1. Undated registered manuscript, Enter Calculus Companion. Source locators: :I2, :I3, and :release. The named internal amplitude construction and the unconstructed joint characteristic map are distinct source claims. https://enter.grok.me/.