AWhat changed
The CMS Collaboration extracted a top-quark spin-entanglement witness from opposite-charge dilepton events in 13 TeV proton collisions, using 36.3 inverse femtobarns of 2016 data. In the selected threshold region, a profile-likelihood analysis corrected for detector effects gave D = −0.480 with total uncertainties of +0.026 and −0.029. This crossed the D = −1/3 separability-witness boundary with an author-reported significance of 5.1 sigma under a signal model including a predicted toponium contribution. The measurement supplies a separate detector and parton-level determination alongside the earlier ATLAS result.
Scientific scope
The CMS Collaboration extracted a top-quark spin-entanglement witness from opposite-charge dilepton events in 13 TeV proton collisions, using 36.3 inverse femtobarns of 2016 data. In the selected threshold region, a profile-likelihood analysis corrected for detector effects gave D = −0.480 with total uncertainties of +0.026 and −0.029. This crossed the D = −1/3 separability-witness boundary with an author-reported significance of 5.1 sigma under a signal model including a predicted toponium contribution. The measurement supplies a separate detector and parton-level determination alongside the earlier ATLAS result. The result applies to the selected parton-level phase space and uses standard-model decay analyzers, simulated acceptance and migration, and signal/background templates. The assumed toponium component changes the extraction and significance; including it does not establish discovery of that state. This is a spin-entanglement witness rather than a Bell-inequality or loophole-free nonlocality test. Literal sign inconsistencies in the source explanation are retained for clarification. Raw event fitting and independent statistical validation were not repeated.
Evidence
The linked original works support the scoped statement and contribution attribution. WRS has not independently replayed experiments or reconstructed a full mathematical proof. The result applies to the selected parton-level phase space and uses standard-model decay analyzers, simulated acceptance and migration, and signal/background templates. The assumed toponium component changes the extraction and significance; including it does not establish discovery of that state. This is a spin-entanglement witness rather than a Bell-inequality or loophole-free nonlocality test. Literal sign inconsistencies in the source explanation are retained for clarification. Raw event fitting and independent statistical validation were not repeated.
Contributors
- The named authors in the research record · SCIENCE: These are the listed authors of the cited contribution sources. Paper authorship does not quantify individual effort. An incomplete list is explicitly marked; same names are not automatically merged.
Provisional WRS assessment, edition 2026-10-28.1. Independent expert calibration is pending. This grade does not certify correctness or assign ownership.
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