Tensionless Strings: A perspective from the worldsheet
Abstract:
We revisit the construction of the tensionless limit of closed
bosonic string theory in the covariant formulation in the light of
Galilean conformal symmetry that rises as the residual gauge symmetry
on the tensionless worldsheet. We relate the analysis of the
fundamentally tensionless theory to the tensionless limit that is
viewed as a contraction of worldsheet coordinates. We are able to
naively see the connection to massless higher spin states. We extend
this analysis to the closed superstring to obtain the Super Gallilean
Conformal Algebra. Analysis of the quantum regime uncovers
interesting physics. The degrees of freedom that appear in the
tensionless string are fundamentally different from the usual string
states. Through a Bogoliubov transformation on the worldsheet, we
link the tensionless vacuum to the usual tensile vacuum. As an
application, we discuss how our analysis can be connected to
Hagedorn, Physics, Left-Right Entanglement Entropy and Boundary
states.