Abstract:
Within the premise of canonical quantisation, we re-examine the quantum
structure of bosonic tensionless string theory. In the classical theory, the worldsheet metric
degenerates and the Bondi-Metnzer-Sachs (BMS) algebra arises as the residual symmetries
on fixing the tensionless equivalent of the conformal gauge. In the quantum regime, we
find, on careful examination, that there are multiple ways to impose constraints to restrict
the physical Hilbert space, which in turn lead to three distinct choices of tensionless vacua.
We analyse these vacua in detail, commenting on various aspects like the central charges
and the spectrum around each of them.
