International Light Cone Advisory Committee


Non-triviality of the vacuum in light-front quantization; and implications for correctly formulating light-front quantization

by John C. Collins (Penn State U.)


It is often stated that the vacuum is trivial when light-front is used, in contrast to equal-time quantization.  In fact this is not the case, as has been known since 1969. I give an elementary review of why this happens, and locate an easy-to-miss but elementary mathematical error in proofs of vacuum triviality.

In the light of this, a careful re-examination and reformulation of the mathematics of light-front quantization is needed, and I lay out a program to do this.  The program builds on some already-known mathematical complications that are easily overlooked.

(Some of the material in this seminar is in arXiv:1801.03960.)

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