### Speaker

Hiroaki Matsunaga

### Description

We extract a light-cone string field theory from Witten’s covariant string field theory.

The covariant string field splits into the light-cone string field and trivial excitations of BRST quartets:

The latter generates the gauge symmetry and covariance.

A new light-cone theory, which has an A-infinity type action, is obtained by path-integrating it out from the Witten theory.

We show that the process of path-integrating-out fields is described by the homological perturbation lemma (for A-infinity) and thus our A-infinity light-cone string field theory has the same tree-level amplitudes as the Witten theory.

[arXiv:1901.08555]