Notes on string theory #5: Modifying the Polyakov action (cosmological constant and Ricci scalar)

We come to the conclusion of Section 1.2 in Polchinski's textbook. In this note we'll discuss how there are two possible modifications that we can make to the Polyakov action (see last note) that preserve Poincaré invariance. The first is a cosmological constant term on the worldsheet. The second modification involves the scalar curvature $latex …

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Cosmological constant, the duality symmetric string, and Atkin-Lehner symmetry

I was going through one of my notebooks and I came across a page with several comments on old papers by Arkady Tseytlin [1] and Gregory Moore [3], respectively. The notes must have been written last autumn at the start of the academic year, because it was around this time my supervisor and I were …

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Generalised supergravity and the dilaton

I spent sometime in the early autumn months thinking about the cosmological constant problem (CC). This was actually secondary, because my primary note taking focused more on S-duality and manifestly duality invariant actions, non-perturbative corrections, and the dilaton. But my supervisor, Tony, has spent a lot of time thinking about this problem, with one of …

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