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Is Physics in the Infinite Momentum Frame Independent of the Compactification Radius?

Alberto Guijosa
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Abstract

With the aim of clarifying the eleven dimensional content of Matrix theory, we examine the dependence of a theory in the infinite momentum frame (IMF) on the (purely spatial) longitudinal compactification radius R. It is shown that in a point particle theory the generic scattering amplitude becomes independent of R in the IMF. Processes with zero longitudinal momentum transfer are found to be exceptional. The same question is addressed in a theory with extended objects. A one-loop type II string amplitude is shown to be R-independent in the IMF, and to coincide with that of the uncompactified theory. No exceptional processes exist in this case. The possible implications of these results for M-theory are discussed. In particular, if amplitudes in M-theory are independent of R in the IMF, Matrix theory can be rightfully expected (in the N -> infty limit) to describe uncompactified M-theory.

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Alberto Guijosa. 2000-09-15. Is Physics in the Infinite Momentum Frame Independent of the Compactification Radius?. https://doi.org/10.1016/s0550-3213(98)00499-4

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