Antimatter Matter

A small degree of matter-antimatter asymmetry, with a baryon number B (ratio of net number of baryons Nb — N-g in a co-moving volume to the entropy S) in the range 10-11 to 10-8. 

The matter - antimatter asymmetry in the Universe and its relation to the underlying symmetries of Nature is of such fundamental importance that a number of large-scale experiments have been undertaken to search for cosmic antimatter. 

A major scientific experiment devoted to the search for antimatter originating from outside of our galaxy is presently being conducted by NASA. The experiment is a part of the project aiming at studies of matter, antimatter and dark matter in space. This project, coordinated by the Department of Energy (DOE), is a large collaboration of more than 30 universities, and will be conducted with the help of a state-of-the-art... 

In view of the current search for antimatter in outer space, the ongoing efforts to produce antihydrogen in laboratory, and the forthcoming experiments with cold antihydrogen we have undertaken the study of matter-antimatter interactions [26, 27, 28, 29, 30, 31, 32]. Such interactions are of interest both for CERN AD experiments on forming antihydrogen, and for the astrophysical search for the presence of antimatter in the Universe. 

This process, which is characteristic of matter-antimatter collisions, is called annihilation and is another example of the interchange of the forms of matter. 

Cohen A., de Rujula A. and Glashow S. A matter-antimatter universe Astrophysical Journal, 495 (1998), 539. 

Some particles created in the early moments following the big bang were destroyed by the process of matter/antimatter annihilation... 

A unique situation of the passage of positrons through an absorber is that as a positron loses its energy by interaction with electrons of the absorber atoms and comes to almost rest, it combines with an electron of an absorber atom. At this instant, both particles (/ + and e ) are annihilated as a result of matter-antimatter encounter to produce two photons of 511 keV, which are emitted in opposite directions ( 180°) (Fig. 1.6). This process is called the... 

A positron and an electron annihilate because (a) they have the same energy (b) they have opposite momentum or (c) it is matter-antimatter encounter ... 

Summarizing the situation, we have derived well-known relations of the special theory of relativity as a consequence of the quantum mechanical superposition principle, involving matter-antimatter quantum states. In passing, we notice that one can include appropriate electromagnetic fields [6] through... 

The origin of X-rays, 7-ray bursts and radiowaves that pervade the Galaxy is as mysterious as the cosmic-ray sources. Evidence is mounting that in most cases these phenomena are linked to violent explosions, thought to include neutron-star quakes, quark nuggets, supernovae, matter-antimatter annihilation, clumping of quasars and colliding stars. Of all space radiations radio phenomena have been studied in most detail. 

Enough energy is generated to propel the product into conjugate space, following the inverse synthetic route. Matter (antimatter) is neither destroyed nor created, but circulated. 

As the plasma moves through the centre of maximum curvature it is forced through the vacumn interface into a space-time domain of inverted chirahty and decreasing pressme. New matter (antimatter) emerges beyond the interface as an equilibrimn mixture of cosmic rays, in a soup of a-particles, as it is squirted out from the black hole into free space. Some of the newly formed nuchdes decay radioactively on moving into regions of lower curvatme and a set of nuclides, characteristic of local cmvatme, smvives. In the solar system the set consists of the 264 stable isotopes of 81 elements described before. The closed periodic sytem of nuclides and anti-nuclides, related by inversion, is consistent with the proposed mode of cosmic circulation of mass. 

Most of their interesting conclusions find a simple explanation in matter-antimatter annihilation through the vacuum interface, as proposed here. 

Quack M (1994) On the measurement of CP-violating energy differences in matter-antimatter enantiomers. Chem Phys Lett 231(4-6) 421 28... 

CP violation has been experimentally established also in B meson decays. However, the observed matter-antimatter asymmetry of the Universe requires additional sources of CP violation. 

After the discovery of parity violation the CP symmetry, i.e., the invariance of the physical laws against the simultaneous transformation of charge and space reflection, was still assumed to be exact. However, in 1964 Cronin and Fitch (Nobel Prize 1980) discovered (Christenson et al. 1964) that the weak interaction violates that as well, although this violation is tiny, not maximal, like that of the P invariance. CP violation makes it possible to differentiate between a world and an antiworld and may be related to the matter - antimatter asymmetry. 

The inflationary period in the evolution of the Universe ended at about 10 s after the Big Bang. At this moment, the constant ordered potential energy density driving the inflation decayed into the particles observed today. Some of them may have belonged to a more exotic class, which can contribute to the violation of the matter-antimatter symmetry if they exhibit sufficiently long lifetimes (see Sect. 12.2.2). The rate of expansion of the horizon in the subsequent radiation- and matter-dominated eras was always faster than the global expansion of the Universe (see O Fig, 12,2). Radiation-dominated means... 

On the interface of neighboring domains of baryonic and antibaryonic matter, quark—antiquark (proton-antiproton) annihilation would lead to the emission of hard X-rays. The absence of this signal makes it highly probable that even if antibaryons were present in the early, hot Universe they had disappeared before the CMBR was emitted. Therefore, the observed baryonic density actually proves the presence of a matter—antimatter asymmetry within the present horizon in our Universe (Rubakov and Shaposhnikov 1996 Riotto and Trodden 1999). 

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