Mirror symmetry, universe

Finally, a possible discovery of chiral materials and primitive life in the universe might throw additional light on this question of the origin of mirror symmetry breaking at prebiotic times. 

We can find the mirror A universe equivalents to all the symmetry operations in the group in a similar way. Thus,... 

It has been also emphasized that the fundamental particles found in this universe may also have their mirror symmetry. 

Mirror Symmetry Breaking - is the Universe Really Racemic ... 

In summary, the model allows for two types of interactions between the mirror spaces, the weak kinematical perturbation and the adiabatic and sudden limits equivalent to Eq. (17) or Eqs. (29)-(34). The overwhelming rate of particles over antiparticles in the Universe is inferred in this picture once the particular particle state has been selected. The Minkowski metric of the special theory of relativity is represented here by a non-positive definite metric, Eq. (8), bringing about a quantum model with a complex symmetric ansatz. Although the latter permits general symmetry violations, it is nevertheless surprising that fundamental transformations between complex symmetric representations and canonical forms come out unitary. 

M. Gardner, The New Ambidextrous Universe. Symmetry and Asymmetry from Mirror Reflections to Superstrings, Third Revised Edition, W. H. Freeman and Co., New York, 1990. 

The space-time symmetry underlying the Lewis model requires further analysis. It has often been speculated that the known universe is one of a pair of symmetry-related worlds. Naan argued forcefully [105] that an element of PCT (Parity-Charge conjugation-Time inversion) symmetry within the universal structure is indispensible to ensure existence. The implication is co-existence of material and anti-material worlds in an unspecified symmetric arrangement. Hence any interaction in the material world must be mirrored in the anti-world and it will be shown that this accords with the suggested mechanism of interaction. 

Whereas both P and C symmetries are individually violated by nature, the combination CP invariance—the exchange of particles with their corresponding antiparticles followed by a reflection in a mirror— was thought to hold absolutely until 1964, when J. W. Cronin, Val L. Fitch, and colleagues showed that CP symmetry was violated in the decay of neutral kaons. This was the one and only violation of CP symmetry that had been observed until March 2001, when the decay of neutral B mesons also violated this symmetry. But these two violations mean that CP invariance is not absolute. With this violation of CP symmetry and with the possibility of baryon nonconservation, it is possible to explain why matter dominates the universe. The explanation, however, is speculative and not very satisfying. 

The Estonian academician G.I. Naan (1964), on the basis of the Bohr-Liiders (1954) theorem, argued that the universe cannot exist without an element of CPT (Charge conjugation-Parity-Time) inversion symmetry, which implies the co-existence of material and anti-material worlds. Any interaction in the material world must be mirrored in the anti-world, but without direct contact between the two domains. Because of the inversion symmetry all conservation laws are automatically satisfied as invariant, at magnitudes of zero. 

The experimental observations are consistent with the intermediacy of a non-classical carbocation called the norbornyl cation (see Figure 11.10), a structure primarily attributed to Winstein. The non-classical structure possesses an internal mirror plane of symmetry, and the endo face of the compound is protected by the bridging interaction. This, at the time, was a highly novel proposal, and it was not universally accepted. The experimental observations could alternatively be explained by invoking two classical carbocations rapidly equilibrating via carbon shifts (Eq. 11.38). The biggest proponent of this explanation was Brown. The distinction between these two possibilities is an important issue to discuss. 

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