Articles de revues : « Matter-antimatter Asymmetry »

1

Bugaev, E. V. « Matter-antimatter asymmetry ». Nuclear Physics B - Proceedings Supplements 122 (juillet 2003) : 98–108. http://dx.doi.org/10.1016/s0920-5632(03)80367-5.

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Perkins, W. A. « On the matter–antimatter asymmetry ». Modern Physics Letters A 30, n^o 31 (14 septembre 2015) : 1550157. http://dx.doi.org/10.1142/s0217732315501576.

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Although the big bang should have produced equal amounts of matter and antimatter, there is evidence that the universe does not contain significant amounts of antimatter. The usual explanations for this matter–antimatter asymmetry involve finding causes for Sakharov’s three conditions to be satisfied. However, if the composite photon theory is correct, antimatter galaxies should appear to us as dark matter, neither emitting light (that we can detect) or reflecting ordinary light. Thus the presence of antimatter galaxies may be harder to detect than previously thought. The large clumps of dark matter that have been observed by weak gravitation lensing could be clusters of antimatter galaxies. “Dark photons,” that are hypothesized to cause self-interactions between dark matter particles, are identified as antiphotons in the composite photon theory. The possibility of a patchwork universe, that had been previously excluded, is also re-examined.

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Enomoto, Seishi, et Tomohiro Matsuda. « Asymmetric preheating ». International Journal of Modern Physics A 33, n^o 25 (10 septembre 2018) : 1850146. http://dx.doi.org/10.1142/s0217751x18501464.

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We study the generation of the matter–antimatter asymmetry during bosonic preheating, focusing on the sources of the asymmetry. If the asymmetry appears in the multiplication factor of the resonant particle production, the matter–antimatter ratio will grow during preheating. On the other hand, if the asymmetry does not grow during preheating, one has to find out another reason. We consider several scenarios for the asymmetric preheating to distinguish the sources of the asymmetry. We also discuss a new baryogenesis scenario, in which the asymmetry is generated without introducing either loop corrections or rotation of a field.

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Robson, Brian Albert. « The Matter-Antimatter Asymmetry Problem ». Journal of High Energy Physics, Gravitation and Cosmology 04, n^o 01 (2018) : 166–78. http://dx.doi.org/10.4236/jhepgc.2018.41015.

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AHLUWALIA, D. V., et M. KIRCHBACH. « PRIMORDIAL SPACETIME FOAM AS AN ORIGIN OF COSMOLOGICAL MATTER–ANTIMATTER ASYMMETRY ». International Journal of Modern Physics D 10, n^o 06 (décembre 2001) : 811–23. http://dx.doi.org/10.1142/s0218271801001608.

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The possibility is raised that the observed cosmological matter–antimatter asymmetry may reside in asymmetric spacetime fluctuations and their interplay with the Stückelberg–Feynman interpretation of antimatter. The presented thesis also suggests that the effect of spacetime fluctuations is to diminish the fine structure constant in the past. Recent studies of the QSO absorption lines provide a 4.1 standard deviation support for this prediction. Our considerations suggest that in the presence of spacetime fluctuations, the principle of local gauge invariance, and the related notion of parallel transport, must undergo fundamental changes.

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Buchmüller, W. « Matter‐antimatter asymmetry of the universe ». Annalen der Physik 513, n^o 1-2 (février 2001) : 95–108. http://dx.doi.org/10.1002/andp.200151301-209.

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Dine, Michael, et Alexander Kusenko. « Origin of the matter-antimatter asymmetry ». Reviews of Modern Physics 76, n^o 1 (16 décembre 2003) : 1–30. http://dx.doi.org/10.1103/revmodphys.76.1.

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Quinn, Helen R., et Michael S. Witherell. « The Asymmetry between Matter and Antimatter ». Scientific American 279, n^o 4 (octobre 1998) : 76–81. http://dx.doi.org/10.1038/scientificamerican1098-76.

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Buchmüller, Wilfried, et Michael Plümacher. « Matter–antimatter asymmetry and neutrino properties ». Physics Reports 320, n^o 1-6 (octobre 1999) : 329–39. http://dx.doi.org/10.1016/s0370-1573(99)00057-5.

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Quinn, Helen R. « The Asymmetry Between Matter and Antimatter ». Physics Today 56, n^o 2 (février 2003) : 30–35. http://dx.doi.org/10.1063/1.1564346.

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Buchmüller, W. « Matter-antimatter asymmetry of the universe ». Annalen der Physik 10, n^o 1-2 (février 2001) : 95–108. http://dx.doi.org/10.1002/1521-3889(200102)10:1/2<95 ::aid-andp95>3.0.co;2-n.

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Rafelski, Johann, Jeremiah Birrell, Andrew Steinmetz et Cheng Tao Yang. « A Short Survey of Matter-Antimatter Evolution in the Primordial Universe ». Universe 9, n^o 7 (27 juin 2023) : 309. http://dx.doi.org/10.3390/universe9070309.

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We offer a survey of the matter-antimatter evolution within the primordial Universe. While the origin of the tiny matter-antimatter asymmetry has remained one of the big questions in modern cosmology, antimatter itself has played a large role for much of the Universe’s early history. In our study of the evolution of the Universe we adopt the position of the standard model Lambda-CDM Universe implementing the known baryonic asymmetry. We present the composition of the Universe across its temperature history while emphasizing the epochs where antimatter content is essential to our understanding. Special topics we address include the heavy quarks in quark-gluon plasma (QGP), the creation of matter from QGP, the free-streaming of the neutrinos, the vanishing of the muons, the magnetism in the electron-positron cosmos, and a better understanding of the environment of the Big Bang Nucleosynthesis (BBN) producing the light elements. We suggest but do not explore further that the methods used in exploring the early Universe may also provide new insights in the study of exotic stellar cores, magnetars, as well as gamma-ray burst (GRB) events. We describe future investigations required in pushing known physics to its extremes in the unique laboratory of the matter-antimatter early Universe.

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Liu, Hao, Jingxu Zhang et Xiongfei Wang. « CP Asymmetry in the Ξ Hyperon Sector ». Symmetry 15, n^o 1 (11 janvier 2023) : 214. http://dx.doi.org/10.3390/sym15010214.

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The Standard Model of particle physics has achieved great success in describing the fundamental particles and their interactions, but there are still some issues that have not been addressed yet. One of the key puzzles is to figure out why there is so much more matter than antimatter in the Universe, regarded as the CP asymmetry. The Ξ hyperon with strangeness S=−2, sometimes so-called the doubly-strange baryon, can provide key information to probe the asymmetry of the matter and antimatter. In this review, we discuss the studies of CP asymmetry in Ξ hyperon decay at E756, HyperCP and BESIII experiments.

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Jentschura, Ulrich David. « Antimatter Free-Fall Experiments and Charge Asymmetry ». Symmetry 13, n^o 7 (1 juillet 2021) : 1192. http://dx.doi.org/10.3390/sym13071192.

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We propose a method by which one could use modified antimatter gravity experiments in order to perform a high-precision test of antimatter charge neutrality. The proposal is based on the application of a strong, external, vertically oriented electric field during an antimatter free-fall gravity experiment in the gravitational field of the Earth. The proposed experimental setup has the potential to drastically improve the limits on the charge-asymmetry parameter ϵ¯q of antimatter. On the theoretical side, we analyze possibilities to describe a putative charge-asymmetry of matter and antimatter, proportional to the parameters ϵq and ϵ¯q, by Lagrangian methods. We found that such an asymmetry could be described by four-dimensional Lorentz-invariant operators that break CPT without destroying the locality of the field theory. The mechanism involves an interaction Lagrangian with field operators decomposed into particle or antiparticle field contributions. Our Lagrangian is otherwise Lorentz, as well as PT invariant. Constraints to be derived on the parameter ϵ¯q do not depend on the assumed theoretical model.

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CARMONA, JOSÉ MANUEL, JOSÉ LUIS CORTÉS, ASHOK DAS, JORGE GAMBOA et FERNANDO MÉNDEZ. « MATTER–ANTIMATTER ASYMMETRY GENERATED AT LOW TEMPERATURES ». Modern Physics Letters A 21, n^o 11 (10 avril 2006) : 883–92. http://dx.doi.org/10.1142/s0217732306020111.

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We explore the possibility of having baryogenesis at temperatures below any dilution mechanism, such as inflation or sphaleron effects at the electroweak transition. We find that large infrared CPT violation (CPTV) effects are a necessary ingredient for such a baryogenesis. We give an explicit example of a theory supporting this scenario at the kinematical level in which such CPTV effects are suppressed at the level of CPT tests based on mass differences between particle and antiparticle.

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Xing, Zhi-zhong. « Cosmological Matter-Antimatter Asymmetry and Neutrino Oscillations ». Nuclear Physics B - Proceedings Supplements 166 (avril 2007) : 30–34. http://dx.doi.org/10.1016/j.nuclphysbps.2006.12.005.

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Tawfik, A. « Matter–Antimatter Asymmetry in Heavy-Ion Collisions ». International Journal of Theoretical Physics 51, n^o 5 (23 novembre 2011) : 1396–407. http://dx.doi.org/10.1007/s10773-011-1015-4.

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Willmann, Lorenz, et Klaus Jungmann. « Matter-antimatter asymmetry - aspects at low energy ». Annalen der Physik 528, n^o 1-2 (1 juillet 2015) : 108–14. http://dx.doi.org/10.1002/andp.201500008.

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El-Mongy, Sayed. « Asymmetry of the Matter-Anti Matter Ratio in the Universe and Violation of E=mc2 : Sayed`s Theory for Matter-Antimatter Chirality and its Correlations ». JOURNAL OF ADVANCES IN PHYSICS 20 (29 décembre 2022) : 338–46. http://dx.doi.org/10.24297/jap.v20i.9356.

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Unity of the laws is a function in divinity of the Creator – Allah. The postulation of the Big Bang that the universe began by symmetrical matter to anti-matter (M/AM) ratio leads to non-matter universe. This article went deeply and simply through the asymmetry and imbalance of (M/AM) ratio at the beginning of the universe and in the time being. A simple derived formula (Sayed`s Matter-Antimatter ratio) quantified the Anti-matter percentage to be ¼ (~25%), while it was ¾ (~75%) for matter at the early universe. This ratio is almost equivalent ~π. It may be concluded that the asymmetry of (M/AM) is due to violation of E=mc2. Comparison of the published and a derived electron antineutrino/neutrino mass ratio was found to be correlated by Sayed`s factor (SF); about 30√πe. The entropy of black hole is inversely correlated with antimatter percentage and (~3/4π). The proton/electron and antineutrino/neutrino mass ratios correlated with their acceleration were also expressed. Based on our current and previous published findings; the ratios of dark energy/dark matter = Hydrogen/Helium = Matter/antimatter ≈π.

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Hughes, Jennifer. « As the Antiworld Turns ». Mechanical Engineering 121, n^o 04 (1 avril 1999) : 50–53. http://dx.doi.org/10.1115/1.1999-apr-2.

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This article focuses on the fact that a single atom of antimatter—in particular, antihydrogen—may unlock fundamental mysteries of our universe and could lead to revolutionary advances in medicine and space travel. Physicists, through experiments due to begin soon in Geneva, Switzerland, hope to produce a relatively large amount of antihydrogen on a regular basis to compare matter and antimatter. Athena and Atrap share the goal of producing antihydrogen atoms at low energies, in a magnetic trap, and comparing the energy levels and behavior of antihydrogen with hydrogen. The Athena collaboration developed out of an attempt to measure the gravitational acceleration of antiprotons toward Earth. Its experiments, which are to cover a range of considerations, will include studies of gravitational acceleration of antimatter. A tiny asymmetry in the way particles of matter and antimatter decay could help substantiate the belief that, at a somewhat later time after the Big Bang, collisions between the matter and antimatter destroyed all the antimatter but left an excess of matter, from which our universe evolved.

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Benaoum, H. B., et A. Övgün. « Matter-antimatter asymmetry induced by non-linear electrodynamics ». Classical and Quantum Gravity 38, n^o 13 (4 juin 2021) : 135019. http://dx.doi.org/10.1088/1361-6382/abfd90.

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Cho, A. « Hints of Greater Matter-Antimatter Asymmetry Challenge Theorists ». Science 328, n^o 5982 (27 mai 2010) : 1087. http://dx.doi.org/10.1126/science.328.5982.1087-a.

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Lambiase, Gaetano, et Parampreet Singh. « Matter–antimatter asymmetry generated by loop quantum gravity ». Physics Letters B 565 (juillet 2003) : 27–32. http://dx.doi.org/10.1016/s0370-2693(03)00761-5.

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Mavromatos, Nick E. « Anomalies, the Dark Universe and Matter-Antimatter asymmetry ». Journal of Physics : Conference Series 2533, n^o 1 (1 juin 2023) : 012017. http://dx.doi.org/10.1088/1742-6596/2533/1/012017.

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Abstract I review a (3+1)-dimensional, string-inspired cosmological model with gravitational anomalies (of Chern-Simons (CS) type) at early epochs, and a totally-antisymmetric torsion, dual to a massless axion-like field (“gravitational axion”), which couples to the CS term. Under appropriate conditions, primordial gravitational waves can condense, leading to a condensate of the CS anomaly term. As a consequence, one obtains inflation in this theory, of running-vacuum-model (RVM) type, without the need for external inflatons. At the end of the inflationary era, chiral fermionic matter is generated, whose gravitational anomalies cancel the primordial ones. On the other hand, chiral anomalies of gauge type, which are also generated by the chiral matter, remain present during the post-inflationary epochs and become responsible for the generation of a non-perturbative mass for the torsion-related gravitational axion, which, in this way, might play the rôle of a Dark Matter component of geometrical origin. Moreover, in this model, stringy non-perturbative effects during the RVM inflationary phase generate periodic structures for the potential of axion-like particles that arise due to compactification, and co-exist with the gravitational axions. Such periodic potential modulations may lead to an enhanced production of primordial black holes during inflation, which in turn affects the profile of the generated gravitational waves during the radiation era, with potentially observable consequences. This model also entails an unconventional mechanism for Leptogenesis, due to Lorentz-violating backgrounds of the gravitational axions that are generated during inflation, as a consequence of the anomaly condensates, and remain undiluted in the radiation era.

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Khabarova, Ksenia, Artem Golovizin et Nikolay Kolachevsky. « Antihydrogen and Hydrogen : Search for the Difference ». Symmetry 15, n^o 8 (18 août 2023) : 1603. http://dx.doi.org/10.3390/sym15081603.

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Our universe consists mainly of regular matter, while the amount of antimatter seems to be negligible. The origin of this difference, known as the baryon asymmetry, remains undiscovered. Since the discovery of antimatter, many experiments have been carried out to study antiparticles and to compare matter and antimatter twins. Two of the most sensitive methods in physics, radiofrequency and optical spectroscopy, can be efficiently used to search for the difference. The successful synthesis and trapping of cold antihydrogen atoms opened the possibility of significantly increasing the sensitivity of matter/antimatter tests. This brief review focuses on a hydrogen/antihydrogen comparison using other independent spectroscopic measurements of single particles in traps and other simple atomic systems like positronium. Although no significant difference is detected in today’s level of accuracy, one can push forward the sensitivity by improving the accuracy of 1S–2S positronium spectroscopy, spectroscopy of hyperfine transition in antihydrogen, and gravitational measurements.

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FELIPE, RICARDO GONZÁLEZ. « NEUTRINOS AND THE MATTER-ANTIMATTER ASYMMETRY IN THE UNIVERSE ». International Journal of Modern Physics E 20, supp01 (décembre 2011) : 56–64. http://dx.doi.org/10.1142/s0218301311040074.

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The discovery of neutrino oscillations provides a solid evidence for nonzero neutrino masses and leptonic mixing. The fact that neutrino masses are so tiny constitutes a puzzling problem in particle physics. From the theoretical viewpoint, the smallness of neutrino masses can be elegantly explained through the seesaw mechanism. Another challenging issue for particle physics and cosmology is the explanation of the matter-antimatter asymmetry observed in Nature. Among the viable mechanisms, leptogenesis is a simple and well-motivated framework. In this paper we briefly review these aspects, making emphasis on the possibility of linking neutrino physics to the cosmological baryon asymmetry originated from leptogenesis.

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Berezhiani, Zurab. « Matter, dark matter, and antimatter in our Universe ». International Journal of Modern Physics A 33, n^o 31 (10 novembre 2018) : 1844034. http://dx.doi.org/10.1142/s0217751x18440347.

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I discuss the possibility of dark matter conversion into our antimatter, assuming that a part of dark matter is represented by a hypothetical mirror matter. In the Early Universe, [Formula: see text] and [Formula: see text] violating interactions between the particles of ordinary and mirror worlds can co-generate their baryon asymmetries in comparable amounts, [Formula: see text], also predicting the sign of mirror baryon asymmetry. At low energies, the same interactions induce particle mixing phenomena between two sectors. In this way, e.g. mirror neutron [Formula: see text] should oscillate into our antineutron [Formula: see text], with probability that depends on environmental conditions as matter density and magnetic fields. This oscillation can be faster than the neutron decay itself, with [Formula: see text] conversion rate accessible for the experimental search. It can have fascinating phenomenological and astrophysical consequences, and can potentially open an unlimited source of energy by transforming dark mirror matter into antimatter in a controllable way.

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GU, PeiHong, FaPeng HUANG, XinMin ZHANG et MingZhe LI. « Origin of the matter-antimatter asymmetry of the universe ». Chinese Science Bulletin 61, n^o 11 (1 mars 2016) : 1151–56. http://dx.doi.org/10.1360/n972016-00003.

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Buchmüller, W., P. Di Bari et M. Plümacher. « Cosmic microwave background, matter–antimatter asymmetry and neutrino masses ». Nuclear Physics B 643, n^o 1-3 (novembre 2002) : 367–90. http://dx.doi.org/10.1016/s0550-3213(02)00737-x.

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Biondini, S., D. Bödeker, N. Brambilla, M. Garny, J. Ghiglieri, A. Hohenegger, M. Laine et al. « Status of rates and rate equations for thermal leptogenesis ». International Journal of Modern Physics A 33, n^o 05n06 (28 février 2018) : 1842004. http://dx.doi.org/10.1142/s0217751x18420046.

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In many realizations of leptogenesis, heavy right-handed neutrinos play the main role in the generation of an imbalance between matter and antimatter in the early Universe. Hence, it is relevant to address quantitatively their dynamics in a hot and dense environment by taking into account the various thermal aspects of the problem at hand. The strong washout regime offers an interesting framework to carry out calculations systematically and reduce theoretical uncertainties. Indeed, any matter–antimatter asymmetry generated when the temperature of the hot plasma [Formula: see text] exceeds the right-handed neutrino mass scale [Formula: see text] is efficiently erased, and one can focus on the temperature window [Formula: see text]. We review recent progress in the thermal field theoretic derivation of the key ingredients for the leptogenesis mechanism: the right-handed neutrino production rate, the CP asymmetry in the heavy-neutrino decays and the washout rates. The derivation of evolution equations for the heavy-neutrino and lepton-asymmetry number densities, their rigorous formulation and applicability are also discussed.

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Madsen, Niels. « Cold antihydrogen : a new frontier in fundamental physics ». Philosophical Transactions of the Royal Society A : Mathematical, Physical and Engineering Sciences 368, n^o 1924 (13 août 2010) : 3671–82. http://dx.doi.org/10.1098/rsta.2010.0026.

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The year 2002 heralded a breakthrough in antimatter research when the first low energy antihydrogen atoms were produced. Antimatter has inspired both science and fiction writers for many years, but detailed studies have until now eluded science. Antimatter is notoriously difficult to study as it does not readily occur in nature, even though our current understanding of the laws of physics have us expecting that it should make up half of the universe. The pursuit of cold antihydrogen is driven by a desire to solve this profound mystery. This paper will motivate the current effort to make cold antihydrogen, explain how antihydrogen is currently made, and how and why we are attempting to trap it. It will also discuss what kind of measurements are planned to gain new insights into the unexplained asymmetry between matter and antimatter in the universe.

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CHAN, TSAN UNG. « WHAT IS A MATTER PARTICLE ? » International Journal of Modern Physics E 15, n^o 01 (février 2006) : 259–72. http://dx.doi.org/10.1142/s0218301306003916.

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Positive baryon numbers (A>0) and positive lepton numbers (L>0) characterize matter particles while negative baryon numbers and negative lepton numbers characterize antimatter particles. Matter particles and antimatter particles belong to two distinct classes of particles. Matter neutral particles are particles characterized by both zero baryon number and zero lepton number. This third class of particles includes mesons formed by a quark and an antiquark pair (a pair of matter particle and antimatter particle) and bosons which are messengers of known interactions (photons for electromagnetism, W and Z bosons for the weak interaction, gluons for the strong interaction). The antiparticle of a matter particle belongs to the class of antimatter particles, the antiparticle of an antimatter particle belongs to the class of matter particles. The antiparticle of a matter neutral particle belongs to the same class of matter neutral particles. A truly neutral particle is a particle identical with its antiparticle; it belongs necessarily to the class of matter neutral particles. All known interactions of the Standard Model conserve baryon number and lepton number; matter cannot be created or destroyed via a reaction governed by these interactions. Conservation of baryon and lepton number parallels conservation of atoms in chemistry; the number of atoms of a particular species in the reactants must equal the number of those atoms in the products. These laws of conservation valid for interaction involving matter particles are indeed valid for any particles (matter particles characterized by positive numbers, antimatter particles characterized by negative numbers, and matter neutral particles characterized by zero). Interactions within the framework of the Standard Model which conserve both matter and charge at the microscopic level cannot explain the observed asymmetry of our Universe. The strong interaction was introduced to explain the stability of nuclei: there must exist a powerful force to compensate the electromagnetic force which tends to cause protons to fly apart. The weak interaction with laws of conservation different from electromagnetism and the strong interaction was postulated to explain beta decay. Our observed material and neutral universe would signify the existence of another interaction that did conserve charge but did not conserve matter.

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GU, PEI-HONG, et UTPAL SARKAR. « B - L CONSERVED BARYOGENESIS ». Modern Physics Letters A 23, n^o 25 (20 août 2008) : 2047–51. http://dx.doi.org/10.1142/s0217732308027357.

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In the presence of anomaly induced sphaleron process, only a B - L asymmetry can be partially converted to the baryon asymmetry while any B + L asymmetry would be completely erased. Thus in any successful baryogenesis theories, B - L is usually violated above the electroweak scale to explain the observed matter–antimatter asymmetry of the universe. However, if any lepton asymmetry is not affected by the sphaleron processes, a B - L conserved theory can still realize the baryogenesis. We present here an SU(5) GUT realization of this scenario, which naturally accommodates small masses of Dirac neutrinos.

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Amelino-Camelia, Giovanni. « Classicality, Matter–Antimatter Asymmetry, and Quantum Gravity Deformed Uncertainty Relations ». Modern Physics Letters A 12, n^o 19 (21 juin 1997) : 1387–92. http://dx.doi.org/10.1142/s0217732397001412.

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Some of the recent work on quantum gravity has involved modified uncertainty relations such that the products of the uncertainties of certain pairs of observables increase with time. It is here observed that this type of modified uncertainty relations would lead to quantum decoherence, which could explain the classical behavior of macroscopic systems, and CPT-violation, which could provide the seed for the emergence of a matter–antimatter asymmetry.

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Manousakis, Efstratios. « On the origin of matter-antimatter asymmetry in the Universe ». Physics Letters B 829 (juin 2022) : 137049. http://dx.doi.org/10.1016/j.physletb.2022.137049.

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Jaramillo Avila, Benjamín Raziel, et David Delepine. « Four Generation MSSM to Generate the Universe Matter-Antimatter Asymmetry ». Journal of Physics : Conference Series 315 (19 août 2011) : 012022. http://dx.doi.org/10.1088/1742-6596/315/1/012022.

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Hambye, Thomas. « CP violation and the matter–antimatter asymmetry of the Universe ». Comptes Rendus Physique 13, n^o 2 (mars 2012) : 193–203. http://dx.doi.org/10.1016/j.crhy.2011.09.007.

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AHLUWALIA-KHALILOVA, D. V. « CHARGE CONJUGATION AND LENSE–THIRRING EFFECT : A NEW ASYMMETRY ». International Journal of Modern Physics D 13, n^o 10 (décembre 2004) : 2361–67. http://dx.doi.org/10.1142/s0218271804006668.

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This essay presents a new asymmetry that arises from the interplay of charge conjugation and Lense–Thirring effect. When applied to Majorana neutrinos, the effects predicts [Formula: see text] oscillations in gravitational environments with rotating sources. Parameters associated with astrophysical environments indicate that the presented effect is presently unobservable for solar neutrinos. But, it will play an important role in supernova explosions, and carries relevance for the observed matter–antimatter asymmetry in the universe.

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MASPERI, LUIS, et MILVA ORSARIA. « BARYOGENESIS THROUGH GRADUAL COLLAPSE OF VORTONS ». International Journal of Modern Physics A 14, n^o 22 (10 septembre 1999) : 3581–96. http://dx.doi.org/10.1142/s0217751x99001664.

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We evaluate the matter–antimatter asymmetry produced by emission of fermionic carriers from vortons which are assumed to be destabilized at the electroweak phase transition. The velocity of contraction of the vorton, calculated through the decrease of its magnetic energy, originates a chemical potential which allows a baryogenesis of the order of the observed value. This asymmetry is not diluted too much by reheating if the collapse of vortons is distributed along an interval of ~ 10-10 sec.

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Robles-Pérez, Salvador J. « Time Reversal Symmetry in Cosmology and the Creation of a Universe–Antiuniverse Pair ». Universe 5, n^o 6 (13 juin 2019) : 150. http://dx.doi.org/10.3390/universe5060150.

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The classical evolution of the universe can be seen as a parametrised worldline of the minisuperspace, with the time variable t being the parameter that parametrises the worldline. The time reversal symmetry of the field equations implies that for any positive oriented solution there can be a symmetric negative oriented one that, in terms of the same time variable, respectively represent an expanding and a contracting universe. However, the choice of the time variable induced by the correct value of the Schrödinger equation in the two universes makes it so that their physical time variables can be reversely related. In that case, the two universes would both be expanding universes from the perspective of their internal inhabitants, who identify matter with the particles that move in their spacetimes and antimatter with the particles that move in the time reversely symmetric universe. If the assumptions considered are consistent with a realistic scenario of our universe, the creation of a universe–antiuniverse pair might explain two main and related problems in cosmology: the time asymmetry and the primordial matter–antimatter asymmetry of our universe.

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LAMBIASE, GAETANO, SUBHENDRA MOHANTY et ARAGAM R. PRASANNA. « NEUTRINO COUPLING TO COSMOLOGICAL BACKGROUND : A REVIEW ON GRAVITATIONAL BARYO/LEPTOGENESIS ». International Journal of Modern Physics D 22, n^o 12 (octobre 2013) : 1330030. http://dx.doi.org/10.1142/s0218271813300309.

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In this paper, we review the theories of origin of matter–antimatter asymmetry in the universe. The general conditions for achieving baryogenesis and leptogenesis in a CPT conserving field theory have been laid down by Sakharov. In this review, we discuss scenarios where a background scalar or gravitational field spontaneously breaks the CPT symmetry and splits the energy levels between particles and antiparticles. Baryon or Lepton number violating processes in proceeding at thermal equilibrium in such backgrounds gives rise to Baryon or Lepton number asymmetry.

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Gu, Pei-Hong. « Unified picture for Dirac neutrinos, dark matter, dark energy and matter–antimatter asymmetry ». Physics Letters B 661, n^o 4 (mars 2008) : 290–94. http://dx.doi.org/10.1016/j.physletb.2008.02.030.

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Nakadaira, Takeshi. « Search for the matter-antimatter asymmetry in the accelerator-produced neutrinos ». Journal of the Atomic Energy Society of Japan 58, n^o 6 (2016) : 376–81. http://dx.doi.org/10.3327/jaesjb.58.6_376.

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García-Bellido, Juan. « Primordial black holes and the origin of the matter–antimatter asymmetry ». Philosophical Transactions of the Royal Society A : Mathematical, Physical and Engineering Sciences 377, n^o 2161 (11 novembre 2019) : 20190091. http://dx.doi.org/10.1098/rsta.2019.0091.

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We review here a new scenario of hot spot electroweak baryogenesis where the local energy released in the gravitational collapse to form primordial black holes (PBHs) at the quark-hadron (QCD) epoch drives over-the-barrier sphaleron transitions in a far from equilibrium environment with just the standard model CP violation. Baryons are efficiently produced in relativistic collisions around the black holes and soon redistribute to the rest of the universe, generating the observed matter–antimatter asymmetry well before primordial nucleosynthesis. Therefore, in this scenario there is a common origin of both the dark matter to baryon ratio and the photon to baryon ratio. Moreover, the sudden drop in radiation pressure of relativistic matter at H 0 / W ± / Z 0 decoupling, the QCD transition and e + e − annihilation enhances the probability of PBH formation, inducing a multi-modal broad mass distribution with characteristic peaks at 10 −6 , 1, 30 and 10 6 M ⊙ , rapidly falling at smaller and larger masses, which may explain the LIGO–Virgo black hole mergers as well as the OGLE-GAIA microlensing events, while constituting all of the cold dark matter today. We predict the future detection of binary black hole (BBH) mergers in LIGO with masses between 1 and 5 M ⊙ , as well as above 80 M ⊙ , with very large mass ratios. Next generation gravitational wave and microlensing experiments will be able to test this scenario thoroughly. This article is part of a discussion meeting issue ‘Topological avatars of new physics’.

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Lima, J. A. S., et D. Singleton. « Matter–antimatter asymmetry and other cosmological puzzles via running vacuum cosmologies ». International Journal of Modern Physics D 27, n^o 11 (août 2018) : 1843016. http://dx.doi.org/10.1142/s0218271818430162.

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Current astronomical observations are successfully explained by the present cosmological paradigm based on the concordance model ([Formula: see text]CDM + Inflation). However, such a scenario is composed of a heterogeneous mix of ingredients for describing the different stages of cosmological evolution. Particularly, it does not give a unified explanation connecting the early- and late-time accelerating inflationary regimes which are separated by many aeons. Other challenges to the concordance model include: a singularity at early times or the emergence of the universe from the quantum gravity regime, the “graceful” exit from inflation to the standard radiation phase, as well as, the coincidence and cosmological constant problems. We show here that a simple running vacuum model or a time-dependent vacuum may provide insight on some of the above open questions (including a complete cosmic history), and also can explain the observed matter–antimatter asymmetry just after the initial deflationary period.

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Berezhiani, Zurab. « Antistars or Antimatter Cores in Mirror Neutron Stars ? » Universe 8, n^o 6 (31 mai 2022) : 313. http://dx.doi.org/10.3390/universe8060313.

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The oscillation of the neutron n into mirror neutron n′, its partner from the dark mirror sector, can gradually transform an ordinary neutron star into a mixed star consisting in part of mirror dark matter. The implications of the reverse process taking place in the mirror neutron stars depend on the sign of baryon asymmetry in the mirror sector. Namely, if it is negative, as predicted by certain baryogenesis scenarios, then n′¯−n¯ transitions create a core of our antimatter gravitationally trapped in the mirror star interior. The annihilation of accreted gas on such antimatter cores could explain the origin of γ-source candidates with an unusual spectrum compatible with baryon–antibaryon annihilation, recently identified in the Fermi LAT catalog. In addition, some part of this antimatter escaping after the mergers of mirror neutron stars can produce the flux of cosmic antihelium and also heavier antinuclei which are hunted in the AMS-02 experiment.

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Zhitnitsky, Ariel. « Axion quark nuggets. Dark matter and matter–antimatter asymmetry : Theory, observations and future experiments ». Modern Physics Letters A 36, n^o 18 (31 mai 2021) : 2130017. http://dx.doi.org/10.1142/s0217732321300172.

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We review a testable, the axion quark nugget (AQN) model outside of the standard WIMP paradigm. The model was originally invented to explain the observed similarity between the dark and the visible components, [Formula: see text], in a natural way as both types of matter are formed during the same QCD transition and proportional to the same dimensional fundamental parameter of the system, [Formula: see text]. In this framework, the baryogenesis is actually a charge segregation (rather than charge generation) process which is operational due to the [Formula: see text]-odd axion field, while the global baryon number of the Universe remains zero. The nuggets and anti-nuggets are strongly interacting but macroscopically large objects with approximately nuclear density. We overview several specific recent applications of this framework. First, we discuss the “solar corona mystery” when the so-called nanoflares are identified with the AQN annihilation events in corona. Secondly, we review a proposal that the recently observed by the Telescope Array puzzling events is a result of the annihilation events of the AQNs under thunderstorm. Finally, we overview a broadband strategy which could lead to the discovery the AQN-induced axions representing the heart of the construction.

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Mavromatos, Nick E., et Sarben Sarkar. « Neutrinos in the Early Universe, Kalb-Ramond Torsion and Matter-Antimatter Asymmetry ». EPJ Web of Conferences 71 (2014) : 00085. http://dx.doi.org/10.1051/epjconf/20147100085.

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JENKINS, ELIZABETH. « TESTING THE LEPTOGENESIS MECHANISM OF THE SEESAW MODEL ». International Journal of Modern Physics A 20, n^o 06 (10 mars 2005) : 1197–203. http://dx.doi.org/10.1142/s0217751x05024080.

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The seesaw theory, the leading theory for particle interactions, provides a viable mechanism for generating the matter-antimatter asymmetry of the universe. Testing the leptogenesis mechanism directly requires measurement of the d=6 operator of the low-energy effective Lagrangian, in addition to the more familiar d=5 operator which generates Majorana masses for the light neutrinos when the electroweak symmetry is spontaneously broken. This important experimental challenge awaits the next generation of particle physicists.

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Grojean, C. « Beyond the standard Higgs after the 125 GeV Higgs discovery ». Philosophical Transactions of the Royal Society A : Mathematical, Physical and Engineering Sciences 373, n^o 2032 (13 janvier 2015) : 20140042. http://dx.doi.org/10.1098/rsta.2014.0042.

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An elementary, weakly coupled and solitary Higgs boson allows one to extend the validity of the Standard Model up to very high energy, maybe as high as the Planck scale. Nonetheless, this scenario fails to fill the universe with dark matter and does not explain the matter–antimatter asymmetry. However, amending the Standard Model tends to destabilize the weak scale by large quantum corrections to the Higgs potential. New degrees of freedom, new forces, new organizing principles are required to provide a consistent and natural description of physics beyond the standard Higgs.

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