Sudarshan: Seven Science Quests
V-A: Universal Theory of Weak Interaction
In the mid-fifties nuclear beta decay was characterized by scalar and tensor interactions. But with this, no universal Fermi Interaction governing nuclear beta decay, muon decay and muon capture would be possible. After the discovery of parity violation in beta decay there was renewed interest, but no satisfactory solution was forthcoming.

In his graduate research under Robert Marshak, Sudarshan studied these questions. He recognized that not all experimental results were consistent and so some of them must be wrong. By a comprehensive and detailed analysis of the results of all the weak decay data he came to the far reaching conclusion that a V-A structure of weak interaction could explain all but four crucial experiments. Marshak and Sudarshan suggested that these four experiments should be redone and if they also yielded the predicted results then there would be universal Vector-Axial Vector (V-A) interaction that would fit all data including muon decay and muon capture. This interaction was "chiral"; that is, it preferred left handed particles. Within a year, the four experiments were redone and gave the results predicted by Sudarshan. The discovery of the universal V-A structure of weak interactions was crucial to the unification of the weak and electromagnetic interactions by Weinberg, Salam, and Glashow.

Sudarshan continued his research on weak interactions, in collaboration with Okubo, Marshak, and Weinberg and studied the decay of strange particles. In the course of the study of decay of the Lambda hyperon, they solved a singular integral equation for the final state interaction about the same time as the celebrated Omnes solution. The isotopic spin selection rules for the decay of the various K-mesons were also worked out.

See more detailed REVIEW and REFERENCES below.
Schedule of symposium talks for V-A: Universal Theory of Weak Interactions.
Next topic overview: II. Symmetry


The Nature of the Four-Fermion Interaction, Proc. of the Conference on Mesons and Newly-Discovered Particles, Padua-Venice, Sept. 1957; with R. E. Marshak; N. Zanichelli, Bologna (1958); reprinted in "Development of the Theory of Weak Interactions", P. K. Kabir (ed.), Gordon and Breach, New York (1964). Also in "A Gift of Prophecy", E. C. G. Sudarshan (ed.) World Scientific, Singapore (1994), pp. 508-515.

Chirality Invariance and the Universal Fermi Interaction; with R. E. Marshak, Phys. Rev. 109 1860-1862 (1958).

Interaction Current in Strangeness-Violating Decays, Phys. Rev. 112, 665-668 (1958); with S. Okubo, R. E. Marshak, W. B. Teutsch and S. Weinberg, reprinted in "The Development of the Theory of Weak Interactions", P. K. Kabir (ed.), Gordon and Breach, New York (1964).

V-A Theory and the Decay of the Λ Hyperon; with S. Okubo and R. E. Marshak
Phys. Rev. 113, 944-954 (1959).

Decay of the Cascade Particles; with S. Okubo and W. B. Teutsch, Phys. Rev. 114, 1148-1149 (1959).

Generalized Ward-Takahashi Identities and Current Algebras, with K. Raman, Phys. Rev. 154, 1499 (1967).

Ten Years of the Universal V-A Weak Interaction Theory and Some Remarks on a Universal Theory of Primary Interactions. Lectures in Theoretical High Energy Physics, H. H. Aly (ed.), Wiley-Interscience (1968).

Origin of the Universal V-A Theory; with R. E. Marshak. In proceedings "50 Years of Weak Interactions", Wingspread Conference, University of Wisconsin, Madison, Wisconsin (1984), pp. 1-15; and in AIP Conference Proceedings 300 "Discovery of Weak Neutral Currents: the Weak Interaction Before and After", A. K. Mann and D. B. Cline (eds.), AIP, New York (1994), pp. 110-124.

Mid-Century Adventures in Particle Physics, Proc. Fermilab Conference, May 1-4, 1985.

Conserved Currents in Weak Interactions; with R. E. Marshak. Frontiers of Physics (Proc. of The Landau Memorial Conference, Tel Aviv, Israel, 6-10 June 1988), E. Gotsman, Y. Ne'eman and A. Voronel (eds.), Pergamon Press, Oxford (1990), pp. 169-182.

Chirality Invariance and the Universal V-A Theory of Weak Interactions; with R. E. Marshak. Frontier Physics: Essays in Honour of Jayme Tiomno, World Scientific Publishing Company, Singapore (1991), pp. 18-42. See also A Gift of Prophecy, E. C. G. Sudarshan (ed.), World Scientific Publishing Co., Singapore (1995), pp. 516-532.


REVIEW: V-A: Universal Theory of Weak Interactions

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Next topic overview: II. Symmetry


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Sudarshan Symposium, Nov. 5-7, 2006
Curriculum Vitae
Seven Science Quests
V-A: Universal Theory
of Weak Interaction
Spin Statistics
Quantum Optical Coherence:
Sudarshan Representation
Quantum Zeno Effect
Theory of Tachyons
Quantum Mechanics
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