Equivalence of loop-corrected tadpole equations to generalized Weyl invariance (consistency conjecture)
Prove that the vacuum stability conditions obtained by summing massless tadpole amplitudes across all genera, \(\sum_{n=0}^{\infty}\langle V_i \rangle_n = 0\), are equivalent to a generalized Weyl invariance condition in the two-dimensional sigma-model, such that any background satisfying these equations is independent of the chosen Weyl gauge.
References
The basic consistency conjecture is that (2.24) is equivalent to a generalized Weyl invariance condition, i.e. that a background which satisfies (2.24) should be independent of a Weyl gauge chosen.
— Sigma model approach to string theory
(2602.10977 - Tseytlin, 11 Feb 2026) in Section 2 (Sigma model and second quantized string theory)