This title appears in the Scientific Report :
2015
Please use the identifier:
http://dx.doi.org/10.1126/science.1257050 in citations.
Please use the identifier: http://hdl.handle.net/2128/10212 in citations.
Ab initio calculation of the neutron-proton mass difference
Ab initio calculation of the neutron-proton mass difference
The existence and stability of atoms rely on the fact that neutrons are more massive than protons. The measured mass difference is only 0.14% of the average of the two masses. A slightly smaller or larger value would have led to a dramatically different universe. Here, we show that this difference r...
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Personal Name(s): | Borsanyi, S. |
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Durr, S. / Fodor, Z. (Corresponding Author) / Hoelbling, C. / Katz, S. D. / Krieg, S. / Lellouch, L. / Lippert, T. / Portelli, A. / Szabo, Kalman / Toth, B. C. | |
Contributing Institute: |
Jülich Supercomputing Center; JSC |
Published in: | Science, 347 (2015) 6229, S. 1452 - 1455 |
Imprint: |
Washington, DC [u.a.]
American Association for the Advancement of Science64196
2015
|
DOI: |
10.1126/science.1257050 |
PubMed ID: |
25814578 |
Document Type: |
Journal Article |
Research Program: |
Computational Science and Mathematical Methods |
Link: |
Get full text OpenAccess OpenAccess |
Publikationsportal JuSER |
Please use the identifier: http://hdl.handle.net/2128/10212 in citations.
The existence and stability of atoms rely on the fact that neutrons are more massive than protons. The measured mass difference is only 0.14% of the average of the two masses. A slightly smaller or larger value would have led to a dramatically different universe. Here, we show that this difference results from the competition between electromagnetic and mass isospin breaking effects. We performed lattice quantum-chromodynamics and quantum-electrodynamics computations with four nondegenerate Wilson fermion flavors and computed the neutron-proton mass-splitting with an accuracy of 300 kilo–electron volts, which is greater than 0 by 5 standard deviations. We also determine the splittings in the Σ, Ξ, D, and Ξcc isospin multiplets, exceeding in some cases the precision of experimental measurements. |