Origin of Unitary Symmetry and Charge Conservation in Strong Interactions

1964 ◽  
Vol 136 (4B) ◽  
pp. B1092-B1096 ◽  
Author(s):  
E. C. G. Sudarshan ◽  
L. O'Raifeartaigh ◽  
T. S. Santhanam
Keyword(s):  
Strong Interactions ◽  
Charge Conservation ◽  
Unitary Symmetry

Tests of unitary symmetry in strong interactions

1965 ◽  
Vol 288 (1413) ◽  
pp. 170-182 ◽  
Keyword(s):  
Perturbation Theory ◽  
Symmetry Breaking ◽  
Dynamical Theory ◽  
Order Perturbation ◽  
Order Perturbation Theory ◽  
Strong Interactions ◽  
First Order ◽  
Unitary Symmetry ◽  
Dynamical Assumption ◽  
First Order Perturbation

After hearing the material presented in the previous talks, one can question the further need for tests of unitary symmetry in strong interactions since it is now clear that unitary symmetry is good enough to play an essential role in any description of strong interactions. However, it is also clear that unitary symmetry is still bad enough to be interesting—in contrast to isospin, which is so good that it cannot teach us anything more about strong interactions. We know that any dynamical theory describing strong interactions must be invariant under isospin transformations. There is nothing further that can be learned about strong interactions from isospin. On the other hand, we know that a dynamical theory correctly describing strong interactions should be invariant under SU 3 transformations only to some approximation. The remarkable regularities observed in the breaking of unitary symmetry (e.g. the mass formula) tell us more about strong interactions than their transformation properties under a particular group. Although these regularities apparently result only from the assumption of certain transformation properties for the symmetry breaking part of the strong interaction, an additional dynamical assumption is required, namely that the symmetry breaking can be treated by first order perturbation theory. It is a test of the detailed dynamics of the system, not merely of the symmetry, to show how such large symmetry breaking effects can be described by what is apparently only first order perturbation theory.

Symmetry properties of strong interactions

1965 ◽  
Vol 288 (1413) ◽  
pp. 147-155 ◽  
Keyword(s):  
High Energy Physics ◽  
Experimental Situation ◽  
High Energy ◽  
Strong Interactions ◽  
Excellent Review ◽  
Unitary Symmetry ◽  
Symmetry Properties ◽  
Energy Physics

I wish to review the predictions of unitary symmetry in relation to the current experimental situation. As far as I am aware there have been no important changes with regard to SU (3) since the excellent review presented by Salam (1964) at the High Energy Physics conference at Dubna (1964). I will thus be brief on SU (3) and leave some time to discuss the exciting developments which have taken place since, in connexion with SU (6).

Deviations from unitary symmetry for resonant states

1965 ◽  
Vol 288 (1413) ◽  
pp. 183-199 ◽  
Keyword(s):  
Gauge Symmetry ◽  
Symmetry Breaking ◽  
Large Mass ◽  
Strong Interactions ◽  
Tensor Form ◽  
Spin Parity ◽  
Unitary Symmetry ◽  
Resonant States ◽  
Charge Independence ◽  
Unitary Tensor

1. The symmetry breaking interactions The fact that the meson or baryon states observed to have a particular spin-parity value appear grouped into unitary patterns of charge multiplets has made it apparent that the strong nuclear interactions satisfy SU 3 symmetry . At the same time, the large mass differences which exist between the charge multiplets constituting a given unitary multiplet show clearly that there also exist moderately strong interactions which do not have this symmetry, although they satisfy the SU 2 symmetry of charge independence and the gauge symmetry of hypercharge conservation. The simplest hypothesis possible for these symmetry breaking interactions is that they have the following unitary tensor form: L m . s . = λ T 3 3 .

scholarly journals Weak interactions and unitary symmetry

1965 ◽  
Vol 288 (1413) ◽  
pp. 161-165
Keyword(s):  
Weak Interactions ◽  
Strong Interactions ◽  
Unitary Symmetry ◽  
Recent Advances

I shall briefly discuss the recent advances in the understanding of weak interactions which have been made possible by the discovery of approximate SU 3 symmetry of strong interactions (Gell-Mann 1961; Ne’eman 1961). I shall only consider here leptonic weak interactions since this is the field in which the SU 3 approach has been more successful.

Unitary symmetry of strong interactions

1962 ◽  
Vol 1 (2) ◽  
pp. 44-49 ◽  
Author(s):  
C.A. Levinson ◽  
H.J. Lipkin ◽  
S. Meshkov
Keyword(s):  
Strong Interactions ◽  
Unitary Symmetry

Weyl reflections in the unitary symmetry theory of strong interactions

1963 ◽  
Vol 30 (3) ◽  
pp. 845-858 ◽  
Author(s):  
A. J. Macfarlane ◽  
E. C. G. Sudarshan ◽  
C. Dullemond
Keyword(s):  
Strong Interactions ◽  
Unitary Symmetry ◽  
Symmetry Theory

200kv superconducting cryo electron microscope

1987 ◽  
Vol 45 ◽  
pp. 642-643
Author(s):  
M. Iwatsuki ◽  
Y. Kokubo ◽  
Y. Harada ◽  
J. Lehman
Keyword(s):  
Electron Microscope ◽  
Structure Analysis ◽  
Organic Materials ◽  
Strong Interactions ◽  
Specimen Preparation ◽  
Great Effort ◽  
Electron Microscopic ◽  
Crystal Fields ◽  
Special Skill ◽  
Long Time

In recent years, the electron microscope has been significantly improved in resolution and we can obtain routinely atomic-level high resolution images without any special skill. With this improvement, the structure analysis of organic materials has become one of the interesting targets in the biological and polymer crystal fields.Up to now, X-ray structure analysis has been mainly used for such materials. With this method, however, great effort and a long time are required for specimen preparation because of the need for larger crystals. This method can analyze average crystal structure but is insufficient for interpreting it on the atomic or molecular level. The electron microscopic method for organic materials has not only the advantage of specimen preparation but also the capability of providing various information from extremely small specimen regions, using strong interactions between electrons and the substance. On the other hand, however, this strong interaction has a big disadvantage in high radiation damage.

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