% IMPORTANT: The following is UTF-8 encoded. This means that in the presence % of non-ASCII characters, it will not work with BibTeX 0.99 or older. % Instead, you should use an up-to-date BibTeX implementation like “bibtex8” or % “biber”. @ARTICLE{Borsanyi:188968, author = {Borsanyi, S. and Durr, S. and Fodor, Z. and Hoelbling, C. and Katz, S. D. and Krieg, S. and Lellouch, L. and Lippert, T. and Portelli, A. and Szabo, Kalman and Toth, B. C.}, title = {{A}b initio calculation of the neutron-proton mass difference}, journal = {Science}, volume = {347}, number = {6229}, issn = {1095-9203}, address = {Washington, DC [u.a.]}, publisher = {American Association for the Advancement of Science64196}, reportid = {FZJ-2015-02252}, pages = {1452 - 1455}, year = {2015}, note = {Preprint: http://arxiv.org/abs/arXiv:1406.4088}, abstract = {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.}, cin = {JSC}, ddc = {500}, cid = {I:(DE-Juel1)JSC-20090406}, pnm = {511 - Computational Science and Mathematical Methods (POF3-511)}, pid = {G:(DE-HGF)POF3-511}, typ = {PUB:(DE-HGF)16}, UT = {WOS:000352136400034}, pubmed = {pmid:25814578}, doi = {10.1126/science.1257050}, url = {https://juser.fz-juelich.de/record/188968}, }