Article
Physics, Particles & Fields
Arthur Hebecker, Simon Schreyer, Gerben Venken
Summary: There has been recent interest in the possibility of accelerated cosmological expansion in the asymptotic regions of a d-dimensional EFT. It is conjectured that such acceleration is only possible if there are metastable de Sitter vacua in more than d dimensions. This result is in line with Swampland bounds on the potential in the field space asymptotics. Additionally, it is found that the Kaluza-Klein scale always falls below the Hubble scale in these asymptotic decompactification limits.
JOURNAL OF HIGH ENERGY PHYSICS
(2023)
Article
Physics, Particles & Fields
Bruno Valeixo Bento, Dibya Chakraborty, Susha Parameswaran, Ivonne Zavala
Summary: This article investigates various string-loop, warping, and curvature corrections in type IIB moduli stabilisation scenarios. By studying weakly-warped LVS de Sitter vacua, it is found that some corrections become less problematic and even helpful in reaching the weakly-warped parameter space. However, other corrections remain dangerous and require small numerical coefficients to preserve the consistency of the weakly-warped LVS de Sitter solution.
JOURNAL OF HIGH ENERGY PHYSICS
(2023)
Article
Physics, Particles & Fields
Shamit Kachru, Manki Kim, Liam McAllister, Max Zimet
Summary: By analyzing the interactions in ten-dimensional supergravity involving D7-branes and anti-D3-branes, it was shown that the equations of motion require the four-dimensional curvature to precisely match the values determined by the four-dimensional effective theory.
JOURNAL OF HIGH ENERGY PHYSICS
(2021)
Article
Physics, Particles & Fields
Shehu AbdusSalam, Chiara Crino, Pramod Shukla
Summary: In this paper, the realization of de Sitter vacua in type IIB superstring compactifications on K3-fibred Swiss-cheese Calabi Yau (CY) orientifolds is studied. The introduction of an (D3) over bar -brane at the tip of a highly warped throat is considered. A systematic search is performed for CY threefolds satisfying the minimal requirements of being K3-fibred and suitable for moduli stabilization. It is found that finding a suitable orientifold involution is a challenging requirement for (D3) over bar -brane uplifting. A global model using a specific K3-fibred CY threefold is presented, in which all moduli can be consistently stabilized in a de Sitter minimum of the scalar potential.
JOURNAL OF HIGH ENERGY PHYSICS
(2023)
Article
Physics, Particles & Fields
Bruno Valeixo Bento, Dibya Chakraborty, Susha Parameswaran, Ivonne Zavala
Summary: The study revisits the problem of moduli stabilization in type IIB flux compactifications, focusing on a warped throat region. A new metastable de Sitter solution is discovered, providing insights into the landscape and swampland of string theory.
JOURNAL OF HIGH ENERGY PHYSICS
(2021)
Article
Physics, Particles & Fields
Iosif Bena, G. Bruno De Luca, Mariana Grana, Gabriele Lo Monaco
Summary: In the analysis of stable four-dimensional de Sitter vacua constructed by compactifying massive Type IIA supergravity with two O8 sources, the first source is interpreted as an O8(-) plane in String Theory, while the second source could correspond to either an O8(+) plane or an O8(-) plane with 16 D8-branes. The latter solution exhibits a tachyonic instability, where the D8-branes move away from the O8(-) plane. Possible ways of distinguishing between these sources are discussed.
JOURNAL OF HIGH ENERGY PHYSICS
(2021)
Article
Physics, Particles & Fields
Suddhasattwa Brahma, Keshav Dasgupta, Radu Tatar
Summary: In this paper, de Sitter space is identified as a coherent state, which can only be realized in full string theory when combined with temporally varying degrees of freedom and quantum corrections. Viewing de Sitter space as a state rather than a vacuum resolves many issues associated with its entropy, zero-point energy, and trans-Planckian censorship.
JOURNAL OF HIGH ENERGY PHYSICS
(2021)
Article
Physics, Particles & Fields
David Andriot, Ludwig Horer, Paul Marconnet
Summary: This paper classifies solutions of 10-dimensional type IIA/B supergravity theories with orientifolds on a 4-dimensional maximally symmetric spacetime multiplied by a 6-dimensional group manifold. It explores previously unexplored solution classes and discovers new solutions including (anti-) de Sitter solutions with intersecting O-4, O-6 and O-6, and Minkowski solutions with 3 intersecting O-5. The paper also presents new no-go theorems against (anti-) de Sitter solutions and conjectures the absence of de Sitter solutions for 2 or less intersecting source sets, indicating that a 4-dimensional effective theory with de Sitter solutions is at most N = 1 supersymmetric.
JOURNAL OF HIGH ENERGY PHYSICS
(2022)
Article
Physics, Particles & Fields
M. Cicoli, I. Garcia Etxebarria, F. Quevedo, A. Schachner, P. Shukla, R. Valandro
Summary: A new method of embedding the Standard Model quiver into compact Calabi-Yau geometries has been proposed, illustrated by constructing a single dP(5) model. This procedure simplifies the original dP(5) quiver gauge theory to a Left-Right symmetric model, with the potential to further break symmetries to the Standard Model gauge group.
JOURNAL OF HIGH ENERGY PHYSICS
(2021)
Article
Physics, Particles & Fields
David Andriot, Ludwig Horer, Paul Marconnet
Summary: In this paper, we classify and study certain supergravity solutions with different spacetime properties. Using new numerical tools, we discover previously unexplored solutions and analyze their properties and stability. We propose a new conjecture regarding the existence of a flat direction.
JOURNAL OF HIGH ENERGY PHYSICS
(2022)
Article
Physics, Particles & Fields
Chiara Crino, Fernando Quevedo, Roberto Valandro
Summary: This study focuses on de Sitter vacua in concrete type IIB Calabi-Yau compactifications with an anti D3-brane for stabilizing Kahler moduli and complex structure moduli, with exponentially large volume. Analysis of the effective field theory parameters ensures validity of approximations, absence of runaway issues, and satisfaction of consistency constraints in the vacua.
JOURNAL OF HIGH ENERGY PHYSICS
(2021)
Article
Physics, Particles & Fields
Heliudson Bernardo, Suddhasattwa Brahma, Keshav Dasgupta, Radu Tatar
Summary: By constructing purely non-perturbative anti-de Sitter vacua in string theory, a new class of phenomenological dS vacua with novel characteristics is generated, avoiding obstacles in other dS constructions. However, constructing TCC-compatible vacua presents difficulties both phenomenologically and in terms of temporal dependencies.
JOURNAL OF HIGH ENERGY PHYSICS
(2021)
Article
Physics, Particles & Fields
Keshav Dasgupta, Maxim Emelin, Mir Mehedi Faruk, Radu Tatar
Summary: The article discusses the possibility of four-dimensional de Sitter solutions appearing in the IIB string landscape in the presence of time-dependent fluxes and quantum corrections, while achieving time-independent Newton constant and moduli stabilization. However, once the time-dependence is removed, solutions with de Sitter isometries seem to lack a simple effective field theory description and fall back into the swampland.
JOURNAL OF HIGH ENERGY PHYSICS
(2021)
Article
Physics, Multidisciplinary
Erik Plauschinn
Summary: In this paper, we study moduli stabilization for type IIB orientifold compactifications on Calabi-Yau three-folds with (non-)geometric fluxes. We derive general properties of non-geometric flux-compactifications, argue for the contribution of fluxes to be similar to D-branes, and exclude supersymmetric Minkowski vacua for certain cases. Additionally, we reassess stable de-Sitter constructions with (non-)geometric H-, F-, Q- and R-fluxes and argue that they are not consistent in string theory.
FORTSCHRITTE DER PHYSIK-PROGRESS OF PHYSICS
(2021)
Article
Physics, Particles & Fields
Filip Landgren
Summary: Motivated by the lack of consensus on whether or not de Sitter (dS) lies in the Swampland, the authors use a braneworld construction and known Anti-de Sitter (AdS) vacua to compute an explicit effective dS cosmology in three dimensions. The cosmological constants are calculated in different scenarios, showing that small positive values admitting a dS cosmology can be obtained in certain cases.
JOURNAL OF HIGH ENERGY PHYSICS
(2022)
Article
Physics, Particles & Fields
Niccolo Cribiori, Christoph Roupec, Magnus Tournoy, Antoine Van Proeyen, Timm Wrase
JOURNAL OF HIGH ENERGY PHYSICS
(2020)
Article
Physics, Particles & Fields
David Andriot, Paul Marconnet, Timm Wrase
JOURNAL OF HIGH ENERGY PHYSICS
(2020)
Article
Astronomy & Astrophysics
David Andriot, Paul Marconnet, Timm Wrase
Summary: This article discusses two newly discovered 10-dimensional supergravity de Sitter solutions and analyzes whether they can be promoted to classical string backgrounds. Despite some positive partial results, both solutions ultimately fail to simultaneously fulfill all requirements. The analysis emphasizes various subtleties and discusses the relation to the problem of scale separation.
Article
Physics, Particles & Fields
Niccolo Cribiori, Susha Parameswaran, Flavio Tonioni, Timm Wrase
Summary: The study of non-supersymmetric string theories may provide insights into why supersymmetry has not been observed in our universe, shedding light on an important aspect of the string landscape. Investigation into misaligned supersymmetry in closed-string theories reveals cancellations between bosons and fermions, even in non-supersymmetric scenarios. Similarly, the same cancellation is observed for open strings through the study of an anti-Dp-brane placed on top of an Op-plane in type II string theory.
JOURNAL OF HIGH ENERGY PHYSICS
(2021)
Article
Physics, Multidisciplinary
Renata Kallosh, Andrei Linde, Timm Wrase, Yusuke Yamada
Summary: Sequestered inflation models are developed where inflation occurs along flat directions in supergravity models derived from type IIB string theory. By using flux potentials and nilpotent multiplets, the flat directions are lifted to phenomenological inflationary plateau potentials. The masses of heavy fields and the volume of extra dimensions change during inflation, but this does not affect the inflationary dynamics.
FORTSCHRITTE DER PHYSIK-PROGRESS OF PHYSICS
(2021)
Article
Physics, Multidisciplinary
Renata Kallosh, Andrei Linde, Timm Wrase, Yusuke Yamada
Summary: Researchers constructed supergravity models that allow the separation of inflation phenomenology from Planckian energy scale physics, using two steps to achieve this goal.
FORTSCHRITTE DER PHYSIK-PROGRESS OF PHYSICS
(2021)
Article
Physics, Particles & Fields
Niccolo Cribiori, Susha Parameswaran, Flavio Tonioni, Timm Wrase
Summary: This article investigates the finite perturbative corrections in non-supersymmetric strings and discusses their physical and mathematical properties through the interplay between modular invariance and misaligned supersymmetry.
JOURNAL OF HIGH ENERGY PHYSICS
(2022)
Article
Physics, Particles & Fields
Fien Apers, Miguel Montero, Thomas Van Riet, Timm Wrase
Summary: This study investigates the flux compactifications of massive IIA supergravity with O6 planes, examining the properties of AdS(3) and AdS(4) vacua and the potential dual CFT(2) and CFT(3) theories. Results show stability of AdS(3) vacua and the absence of integer dimensions for operators in the putative CFT2 dual theories.
JOURNAL OF HIGH ENERGY PHYSICS
(2022)
Article
Physics, Particles & Fields
Jacob Bardzell, Eduardo Gonzalo, Muthusamy Rajaguru, Danielle Smith, Timm Wrase
Summary: This article revisits flux compactifications of type IIB string theory on rigid Calabi-Yau manifolds. This relatively unexplored part of the string landscape contains many interesting four-dimensional solutions, and discusses how these solutions fit into the swampland conjectures.
JOURNAL OF HIGH ENERGY PHYSICS
(2022)
Article
Physics, Particles & Fields
Renata Kanosh, Andrei Linde, Timm Wrase, Yusuke Yamada
Summary: This article discusses the tachyonic instabilities caused by goldstino condensation in the Volkov-Akulov (VA) model, related supergravity models, and the KKLT model in string theory. The authors of [1] constructed a specific model with two unconstrained interacting chiral superfields that have linearly realized supersymmetry and an unstable vacuum state. However, it is shown that the UV limit of their model is discontinuous and the vacuum instability proposed in [1] is not relevant to the VA model, related supergravity models, and the KKLT construction.
JOURNAL OF HIGH ENERGY PHYSICS
(2022)
Article
Physics, Particles & Fields
David Andriot, Paul Marconnet, Muthusamy Rajaguru, Timm Wrase
Summary: Classical flux compactifications are an important research field in string theory, providing a testing ground for various conjectures. This paper focuses on type II supergravity compactifications on 6d group manifolds towards 4d maximally symmetric spacetimes, and develops a code for automated calculations and analysis.
JOURNAL OF HIGH ENERGY PHYSICS
(2022)
Article
Physics, Particles & Fields
Katrin Becker, Eduardo Gonzalo, Johannes Walcher, Timm Wrase
Summary: This article investigates Type IIB flux vacua based on Landau-Ginzburg models, providing insights into non-geometric and strongly-coupled string landscapes. By studying supersymmetric flux configurations, it is found that there are massless fields that are not all flat directions of the super-potential at higher order. Additionally, new supersymmetric 4d N = 1 Minkowski and AdS vacua are described and compared with other swampland conjectures.
JOURNAL OF HIGH ENERGY PHYSICS
(2022)
Article
Astronomy & Astrophysics
N. Cribiori, D. Junghans, V. Van Hemelryck, T. Van Riet, T. Wrase
Summary: The study revisits AdS(4) flux vacua with scale separation in type II supergravity and M-theory, showing that massless IIA allows weakly and strongly coupled solutions with fine-tuned classical orientifold backreaction. Evidence is provided that strongly coupled solutions in 11D supergravity can be lifted to scale-separated and sourceless (but classically singular) geometries.
Article
Physics, Particles & Fields
Abhishek Chowdhury, Abhiram Kidambi, Sameer Murthy, Valentin Reys, Timm Wrase
JOURNAL OF HIGH ENERGY PHYSICS
(2020)
Article
Astronomy & Astrophysics
Niccolo Cribiori, Christoph Roupec, Timm Wrase, Yusuke Yamada