Results 31 to 40 of about 572 (144)
A Note on the dS Swampland Conjecture, Non‐BPS Branes and K‐Theory
Fortschritte der Physik, Volume 67, Issue 11, November 2019., 2019 Abstract We point out that the de Sitter swampland conjecture would be falsified if classical fluxed Type IIA orientifold vacua with a single non‐BPS D7‐brane were indeed part of the string theory landscape. In other words, the dS swampland conjecture implies the cancellation of K‐theory charges on a compact space.
Ralph Blumenhagen +2 more
wiley +1 more source
Dilaton vertices of the closed superstring and the heterotic string
Physics Letters B, 1988 Abstract BRST - and conformally invariant dilaton vertices of the closed superstring and the heterotic string are constructed, whose counter terms are consistent with the dilaton terms introduced in the non-linear sigma model approach of string theory.
openaire +1 more source
The Landscape, the Swampland and the Era of Precision Cosmology
Fortschritte der Physik, Volume 67, Issue 1-2, January-February 2019., 2019 Abstract We review the advanced version of the KKLT construction and pure de Sitter supergravity, involving a nilpotent multiplet, with regard to various conjectures that de Sitter state cannot exist in string theory. We explain why we consider these conjectures problematic and not well motivated, and why the recently proposed alternative string theory
Yashar Akrami +3 more
wiley +1 more source
State counting on fibered CY 3-folds and the non-Abelian weak gravity conjecture
Journal of High Energy Physics, 2021 We extend the dictionary between the BPS spectrum of Heterotic strings and the one of F-/M-theory compactifications on K3 fibered Calabi-Yau 3-folds to cases with higher rank non-Abelian gauge groups and in particular to dual pairs between Heterotic CHL ...
Cesar Fierro Cota +2 more
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CCNV Space‐Times as Potential Supergravity Solutions
Advances in Mathematical Physics, Volume 2018, Issue 1, 2018., 2018 It is of interest to study supergravity solutions preserving a nonminimal fraction of supersymmetries. A necessary condition for supersymmetry to be preserved is that the space‐time admits a Killing spinor and hence a null or time‐like Killing vector field.
A. Coley +3 more
wiley +1 more source
Pair production and gravity as the weakest force
Journal of High Energy Physics, 2020 The Weak Gravity Conjecture (WGC) is usually formulated in terms of the stability of extremal black-holes or in terms of long distance Coulomb/Newton potentials.
Eduardo Gonzalo, Luis E. Ibáñez
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On the existence of heterotic-string and type-II-superstring field theory vertices
Journal of Geometry and PhysicsWe consider two problems associated to the space of Riemann surfaces that are closely related to string theory. We first consider the problem of existence of heterotic-string and type-II-superstring field theory vertices in the product of spaces of bordered surfaces parameterizing left- and right-moving sectors of these theories. It turns out that this
Seyed Faroogh Moosavian, Yehao Zhou
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Calabi‐Yau Manifolds, Hermitian Yang‐Mills Instantons, and Mirror Symmetry
Advances in High Energy Physics, Volume 2017, Issue 1, 2017., 2017 We address the issue of why Calabi‐Yau manifolds exist with a mirror pair. We observe that the irreducible spinor representation of the Lorentz group Spin(6) requires us to consider the vector spaces of two forms and four forms on an equal footing. The doubling of the two‐form vector space due to the Hodge duality doubles the variety of six‐dimensional
Hyun Seok Yang +2 more
wiley +1 more source
Subleading soft theorem for multiple soft gravitons
Journal of High Energy Physics, 2017 We derive the subleading soft graviton theorem in a generic quantum theory of gravity for arbitrary number of soft external gravitons and arbitrary number of finite energy external states carrying arbitrary mass and spin.
Subhroneel Chakrabarti +4 more
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Fortschritte der Physik, Volume 73, Issue 9-10, October 2025.Abstract The unification of conformal and fuzzy gravities with internal interactions is based on the facts that i) the tangent group of a curved manifold and the manifold itself do not necessarily have the same dimensions and ii) both gravitational theories considered here have been formulated in a gauge theoretic way.
Gregory Patellis +3 more
wiley +1 more source