Regularization of identity based solution in string field theory

Understand

We demonstrate that an Erler-Schnabl type solution in cubic string field theory can be naturally interpreted as a gauge invariant regularization of an identity based solution.

• We consider a solution which interpolates between an identity based solution and ordinary Erler-Schnabl one.
• Two gauge invariant quantities, the classical action and the closed string tadpole, are evaluated for finite value of the gauge parameter.
• It is explicitly checked that both of them are independent of the gauge parameter.