Related papers: Four Dimensional Supergravity from String Theory
A short introduction to N = 1 supergravity in four dimensions in the superspace approach is given emphasising on all steps to obtain the final Lagrangian. In particular starting from geometrical principles and the introduction of…
Through their respective sigma models, a bosonic string and a superstring can be coupled to (super)gravity fields. These are subsequently forced to satisfy their right classical equation of motions, as a consequence of quantization of the…
The superspace formulation of N=1 conformal supergravity in four dimensions is demonstrated to be equivalent to the conventional component field approach based on the superconformal tensor calculus. The detailed correspondence between two…
We study the inclusion of point and string matter in the deSitter gauge theory, or MacDowell-Mansouri formulation of four dimensional gravity. We proceed by locally breaking the gauge symmetries of general relativity along worldlines and…
Using the hybrid formalism with manifest $N=1$ $d=4$ spacetime supersymmetry, we construct the quadratic term in the heterotic superstring field theory action. As in open superstring field theory using the hybrid formalism, the heterotic…
We propose a modification of the Nambu-Goto action for the bosonic string which is compatible with the existence of a minimum area at the Planck scale. The result is a phenomenological action based on the observation that LQG tells us that…
A four dimensional Superstring is constructed starting from a twenty six dimensional bosonic string. Fermions are introduced by noting the Manselstam's proof of equivalence of two fermions to one boson in 1+1 dimensions. The action of the…
We give a linearized but otherwise complete supersymmetric action for ${\cal N}=(4,0)$ supergravity in six dimensions, using a Kaluza-Klein-type $5+1$ split of coordinates and fields. We provide in particular a significantly simplified…
A new heterotic N=2 string with manifest target space supersymmetry is constructed by combining a conventional N=2 string in the right-moving sector and a Green-Schwarz-Berkovits type string in the left-moving sector. The corresponding…
Some relationships between string theories and eleven-dimensional supergravity are discussed and reviewed. We see how some relationships can be derived from others. The cases of N=2 supersymmetry in nine dimensions and N=4 supersymmetry in…
We derive the equations of motion of type II 4D supergravity in superspace. This is achieved by coupling the Type II Berkovits' hybrid superstring to an N=2 curved background and requiring that the sigma-model has N=(2,2) superconformal…
We construct an action for four-dimensional extended string Newton-Cartan gravity which is an extension of the string Newton-Cartan gravity that underlies nonrelativistic string theory. The action can be obtained as a nonrelativistic limit…
We discuss duality between Type IIA string theory, eleven-dimensional supergravity, and heterotic string theory in four spacetime dimensions with $N=1$ supersymmetry. We find theories whose infrared limit is trivial at enhanced symmetry…
A theory of gravitation in 4D is presented with strings used in the material action in $U_4$ spacetime. It is shown that the string naturally gives rise to torsion. It is also shown that the equation of motion a string follows from the…
We evaluate in great detail one-loop four-graviton field theory amplitudes in pure N=4 D=4 supergravity. The expressions are obtained by taking the field theory limits of (4,0) and (2,2) space-time supersymmetric string theory models. For…
A concise geometrical formulation of N=4 supergravity containing an antisymmetric tensor gauge field is given in central charge superspace: graviphotons are identified in the super-vielbein on the same footing as the vierbein and the…
We fully compute the N=1 supersymmetrization of the fourth power of the Weyl tensor in d=4 x-space with the auxiliary fields. In a previous paper, we showed that their elimination requires an infinite number of terms; we explicitely compute…
We revisit the four-dimensional theory of gravity that arises from string theory with higher-derivative corrections. By compactifying and truncating the ten-dimensional effective action of heterotic string theory at first order in…
We construct a class of quadratic gauge invariant actions for extended string fields defined on the tensor product of open superstring state space for multiple open string Neveu-Schwarz (NS) sectors with or without one Ramond (R) sector.…
We discuss in detail how string-inspired lineal gravity can be formulated as a gauge theory based on the centrally extended Poincar\'e group in $(1+1)$ dimensions. Matter couplings are constructed in a gauge invariant fashion, both for…