The fundamental string length, which is an essential part of string theory,explicitly breaks scale invariance. However, in field theory we demonstratedrecently that the gravitational constant, which is directly related to thestring length, can be promoted to a dynamical field if the standard modelcoupled to gravity (SM+GR) is lifted to a locally scale (Weyl) invarianttheory. The higher gauge symmetry reveals previously unknown field patcheswhose inclusion turn the classically conformally invariant SM+GR into ageodesically complete theory with new cosmological and possibly furtherphysical consequences. In this paper this concept is extended to string theoryby showing how it can be Weyl lifted with a local scale symmetry acting ontarget space background fields. In this process the string tension (fundamentalstring length) is promoted to a dynamical field, in agreement with the paralleldevelopments in field theory. We then propose a string theory in a geodesicallycomplete cosmological stringy background which suggests previously unimagineddirections in the stringy exploration of the very early universe.
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