Supersymmetry breaking warped throats and the weak gravity conjecture

Abstract We investigate interactions between branes of various dimensions, both charged and uncharged, in three non-supersymmetric string models. These include the USp(32) and U(32) orientifold projections of the type IIB and type 0B strings, as well as the SO(16)×SO(16) projection of the exceptional heterotic string. The resulting ten-dimensional spectra are free of tachyons, and the combinations of branes that they contain give rise to rich and varied dynamics. We compute static potentials for parallel stacks of branes in three complementary regimes: the probe regime, in which one of the two stacks is parametrically heavier than the other, the string-amplitude regime, in which both stacks are light, and the holographic regime. Whenever comparisons are possible, we find qualitative agreement despite the absence of supersymmetry. For charged branes, our analysis reveals that the Weak Gravity Conjecture is satisfied in a novel way via a renormalization of the effective charge-to-tension ratio.

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Low-energy supersymmetry breaking from string flux compactifications: Benchmark scenarios

Journal of High Energy Physics ◽

10.1088/1126-6708/2006/04/040 ◽

2006 ◽

Vol 2006 (04) ◽

pp. 040-040 ◽

Cited By ~ 20

Author(s):

Benjamin C Allanach ◽

Fernando Quevedo ◽

Kerim Suruliz

Keyword(s):

Flux Compactifications ◽

Supersymmetry Breaking ◽

Low Energy

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Explicit soft supersymmetry breaking in the heterotic M-theory B − L MSSM

Journal of High Energy Physics ◽

10.1007/jhep08(2021)033 ◽

2021 ◽

Vol 2021 (8) ◽

Author(s):

Anthony Ashmore ◽

Sebastian Dumitru ◽

Burt A. Ovrut

Keyword(s):

Line Bundle ◽

Supersymmetry Breaking ◽

Moduli Space ◽

Initial Conditions ◽

Low Energy ◽

Strongly Coupled ◽

Hidden Sector ◽

Effective Lagrangian ◽

Soft Supersymmetry Breaking ◽

M Theory

Abstract The strongly coupled heterotic M-theory vacuum for both the observable and hidden sectors of the B − L MSSM theory is reviewed, including a discussion of the “bundle” constraints that both the observable sector SU(4) vector bundle and the hidden sector bundle induced from a single line bundle must satisfy. Gaugino condensation is then introduced within this context, and the hidden sector bundles that exhibit gaugino condensation are presented. The condensation scale is computed, singling out one line bundle whose associated condensation scale is low enough to be compatible with the energy scales available at the LHC. The corresponding region of Kähler moduli space where all bundle constraints are satisfied is presented. The generic form of the moduli dependent F-terms due to a gaugino superpotential — which spontaneously break N = 1 supersymmetry in this sector — is presented and then given explicitly for the unique line bundle associated with the low condensation scale. The moduli-dependent coefficients for each of the gaugino and scalar field soft supersymmetry breaking terms are computed leading to a low-energy effective Lagrangian for the observable sector matter fields. We then show that at a large number of points in Kähler moduli space that satisfy all “bundle” constraints, these coefficients are initial conditions for the renormalization group equations which, at low energy, lead to completely realistic physics satisfying all phenomenological constraints. Finally, we show that a substantial number of these initial points also satisfy a final constraint arising from the quadratic Higgs-Higgs conjugate soft supersymmetry breaking term.

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Weak gravity bounds in asymptotic string compactifications

Journal of High Energy Physics ◽

10.1007/jhep06(2021)162 ◽

2021 ◽

Vol 2021 (6) ◽

Author(s):

Brice Bastian ◽

Thomas W. Grimm ◽

Damian van de Heisteeg

Keyword(s):

Black Holes ◽

Moduli Space ◽

Mass Formula ◽

Complex Structure ◽

Mass Ratio ◽

De Sitter ◽

String Compactifications ◽

Type Iib String Theory ◽

Bps States ◽

Weak Gravity

Abstract We study the charge-to-mass ratios of BPS states in four-dimensional $$ \mathcal{N} $$ N = 2 supergravities arising from Calabi-Yau threefold compactifications of Type IIB string theory. We present a formula for the asymptotic charge-to-mass ratio valid for all limits in complex structure moduli space. This is achieved by using the sl(2)-structure that emerges in any such limit as described by asymptotic Hodge theory. The asymptotic charge-to-mass formula applies for sl(2)-elementary states that couple to the graviphoton asymptotically. Using this formula, we determine the radii of the ellipsoid that forms the extremality region of electric BPS black holes, which provides us with a general asymptotic bound on the charge-to-mass ratio for these theories. Finally, we comment on how these bounds for the Weak Gravity Conjecture relate to their counterparts in the asymptotic de Sitter Conjecture and Swampland Distance Conjecture.

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Standard model from a supergravity model with a naturally small cosmological constant

Journal of High Energy Physics ◽

10.1007/jhep05(2021)181 ◽

2021 ◽

Vol 2021 (5) ◽

Author(s):

Shing Yan Li ◽

Yu-Cheng Qiu ◽

S.-H. Henry Tye

Keyword(s):

String Theory ◽

Standard Model ◽

Cosmological Constant ◽

Supersymmetry Breaking ◽

Supersymmetric Standard Model ◽

Degrees Of Freedom ◽

Interaction Terms ◽

Supersymmetric Version ◽

The Standard Model ◽

Linear Version

Abstract Guided by the naturalness criterion for an exponentially small cosmological constant, we present a string theory motivated 4-dimensional $$ \mathcal{N} $$ N = 1 non-linear supergravity model (or its linear version with a nilpotent superfield) with spontaneous supersymmetry breaking. The model encompasses the minimal supersymmetric standard model, the racetrack Kähler uplift, and the KKLT anti-D3-branes, and use the nilpotent superfield to project out the undesirable interaction terms as well as the unwanted degrees of freedom to end up with the standard model (not the supersymmetric version) of strong and electroweak interactions.

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String defects, supersymmetry and the Swampland

Journal of High Energy Physics ◽

10.1007/jhep11(2020)125 ◽

2020 ◽

Vol 2020 (11) ◽

Author(s):

Carlo Angelantonj ◽

Quentin Bonnefoy ◽

Cezar Condeescu ◽

Emilian Dudas

Keyword(s):

Supersymmetry Breaking ◽

Dimensional Theory ◽

Consistency Conditions ◽

Tensor Multiplet ◽

Microscopic Origin

Abstract Recently, Kim, Shiu and Vafa proposed general consistency conditions for six dimensional supergravity theories with minimal supersymmetry coming from couplings to strings. We test them in explicit perturbative orientifold models in order to unravel the microscopic origin of these constraints. Based on the perturbative data, we conjecture the existence of null charges Q∙Q = 0 for any six-dimensional theory with at least one tensor multiplet, coupling to string defects of charge Q. We then include the new constraint to exclude some six-dimensional supersymmetric anomaly-free examples that have currently no string or F-theory realization. We also investigate the constraints from the couplings to string defects in case where supersymmetry is broken in tachyon free vacua, containing non-BPS configurations of brane supersymmetry breaking type, where the breaking is localized on antibranes. In this case, some conditions have naturally to be changed or relaxed whenever the string defects experience supersymmetry breaking, whereas the constraints are still valid if they are geometrically separated from the supersymmetry breaking source.

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The UV fate of anomalous U(1)s and the Swampland

Journal of High Energy Physics ◽

10.1007/jhep11(2020)063 ◽

2020 ◽

Vol 2020 (11) ◽

Author(s):

Nathaniel Craig ◽

Isabel Garcia Garcia ◽

Graham D. Kribs

Keyword(s):

Quantum Gravity ◽

Gauge Theories ◽

Critical Size ◽

Gauge Coupling ◽

Low Energy ◽

Gravitational Anomaly ◽

Light Vector ◽

Energy Theory ◽

The Cost ◽

Weak Gravity

Abstract Massive U(1) gauge theories featuring parametrically light vectors are suspected to belong in the Swampland of consistent EFTs that cannot be embedded into a theory of quantum gravity. We study four-dimensional, chiral U(1) gauge theories that appear anomalous over a range of energies up to the scale of anomaly-cancelling massive chiral fermions. We show that such theories must be UV-completed at a finite cutoff below which a radial mode must appear, and cannot be decoupled — a Stückelberg limit does not exist. When the infrared fermion spectrum contains a mixed U(1)-gravitational anomaly, this class of theories provides a toy model of a boundary into the Swampland, for sufficiently small values of the vector mass. In this context, we show that the limit of a parametrically light vector comes at the cost of a quantum gravity scale that lies parametrically below MP1, and our result provides field theoretic evidence for the existence of a Swampland of EFTs that is disconnected from the subset of theories compatible with a gravitational UV-completion. Moreover, when the low energy theory also contains a U(1)3 anomaly, the Weak Gravity Conjecture scale makes an appearance in the form of a quantum gravity cutoff for values of the gauge coupling above a certain critical size.

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