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Analogous to the background independent open string field theory by Witten. If there isn't, what are the main stumbling blocks preventing its construction?

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up vote 8 down vote accepted

An original article is

  • Ashoke Sen, Barton Zwiebach, Quantum Background Independence of Closed String Field Theory (arXiv:hep-th/9311009)

An old spr comment by Sabbir Rahman gives a survey of the history of some of these developments.

More references are here.

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As far as I understand, Sen and Zweibach consider "usual" closed string theory, which is not manifestly background independent, and prove that the theories on different backgrounds are equivalent. However, Witten's theory uses the space of backgrounds (BCFTs) as a classical history space which is a manifestly background independent framework. The problem is that he considers BCFTs with different boundary behavior but the same worldsheet-bulk behavior. Apparently this is sufficient for the same reason ordinary open string field theory contains closed strings. – Squark Oct 21 '11 at 1:41
However, one would like to have a closed string analogue, that is, a theory whose classical history space is the space of all CFTs. This would be framework with completely manifest background independence. – Squark Oct 21 '11 at 1:42
Sure, but you asked "is there background independent CSFT?". The closest to manifest background invariance in CSFT that I am aware of is Sen, Zwiebach "Background Independent Algebraic Structures in Closed String Field Theory" (arXiv:hep-th/9408053) – Urs Schreiber Oct 21 '11 at 8:43

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