“Kalb–Ramond field”的意思、由来-开放百科全书

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Kalb–Ramond field

释义

Details
See also
References

In theoretical physics in general and string theory in particular, the Kalb–Ramond field (named after Michael Kalb and Pierre Ramond),^[1] also known as the Kalb–Ramond B-field^[2] or Kalb–Ramond NS–NS B-field,^[3] is a quantum field that transforms as a two-form, i.e., an antisymmetric tensor field with two indices.^[4]^[5]

The adjective "NS" reflects the fact that in the RNS formalism, these fields appear in the NS–NS sector in which all vector fermions are anti-periodic. Both uses of the word "NS" refer to André Neveu and John Henry Schwarz, who studied such boundary conditions (the so-called Neveu–Schwarz boundary conditions) and the fields that satisfy them in 1971.^[6]

Details

The Kalb–Ramond field generalizes the electromagnetic potential but it has two indices instead of one. This difference is related to the fact that the electromagnetic potential is integrated over one-dimensional worldlines of particles to obtain one of its contributions to the action while the Kalb–Ramond field must be integrated over the two-dimensional worldsheet of the string. In particular, while the

action for a charged particle moving in an electromagnetic

potential is given by

that for a string coupled to the Kalb–Ramond field has the form

This term in the action implies that the fundamental string of string theory is a source of the NS–NS B-field, much like charged particles are sources of the electromagnetic field.

The Kalb–Ramond field appears, together with the metric tensor and dilaton, as a set of massless excitations of a closed string.

References

1. ^M. Kalb and Pierre Ramond, "Classical direct interstring action." Phys. Rev. D 9 (1974), 2273–2284.
2. ^Andrei S. Losev, Andrei Marshakov, Anton M. Zeitlin, [https://arxiv.org/abs/hep-th/0510065 "On First Order Formalism in String Theory"], p. 1.
3. ^Alejandro Gaona, J. Antonio Garcia, [https://arxiv.org/abs/hep-th/0610022 "First Order Actions and Duality"], p. 13.
4. ^{{Cite journal|author=Michael Kalb and Pierre Ramond|year=1974|title=Classical direct interstring action|journal=Phys. Rev. D |volume=9|issue=8|pages=2273–2284|doi=10.1103/PhysRevD.9.2273|bibcode= 1974PhRvD...9.2273K}}
5. ^See also: Ogievetsky V. I., Polubarinov I. V. (1967). Sov. J. Nucl. Phys. 4. 156 (Yad. Fiz 4, 216).
6. ^Neveu, A., Schwarz, J. (1971). "Tachyon-free dual model with a positive-intercept trajectory." Physics Letters, 34B, 517–518.

2 : String theory|Gauge bosons

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