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Limits RegistryBASE at CERN compared the cyclotron frequencies of antiprotons and negative hydrogen ions over 18 months and found the proton and antiproton charge-to-mass ratios equal to 16 parts per trillion, published in Nature in January 2022. It is the most precise test of CPT symmetry with baryons and also tests the weak equivalence principle for antimatter.
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BASE at CERN compared the cyclotron frequencies of antiprotons and negative hydrogen ions over 18 months and found the proton and antiproton charge-to-mass ratios equal to 16 parts per trillion, published in Nature in January 2022. It is the most precise test of CPT symmetry with baryons and also tests the weak equivalence principle for antimatter.
The smallest relative uncertainty in a direct comparison of the charge-to-mass ratios of the proton and antiproton.
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1 accepted Claim, with 1 linked evidence records.
Permanent ID limitsregistry.com/limits/LR-PROTON-ANTIPROTON-CHARGE-MASS-COMPARISON
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Limits Registry. LR-PROTON-ANTIPROTON-CHARGE-MASS-COMPARISON. Most precise comparison of proton and antiproton charge-to-mass ratios. 2026.