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Questions tagged [supergravity]

Supergravity is a classical supersymmetric unification theory. It appears in low-energy classical limits of string-theory.

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What superstring or brane phenomenology can be observed in LHC heavy ion collisions?

What superstring or brane phenomenology can be observed in heavy ion collisions at the LHC energy densities. Of course, I am aware that LHC experiments can constrain the conclusions from the ...
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What is a global limit in gauged supergravity?

Does anyone know what a global limit (rigid limit), where the gauge coupling constant is zero, in gauged supergravity is?
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Does anyone know how to symmetrize $\gamma$-matrices?

I'm trying to construct the SO(5, 5) $\gamma$-matrices which are real and symmetric. Recently, I have 6 symmetric and 4 antisymmetric $\gamma$-matrices ($6_S + 4_A$ representation). How can I ...
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IIB Supergravity from worldsheet (super)conformal invariance of Green-Schwarz string

After reading this question How are low energy effective actions derived in string theory? I began to wonder what is the coupling of the string to the other sugra fields. In almost all textbooks ...
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Why are photons particles and waves, instead of particles that simply move in a wave pattern?

I understand the double slit experiment, but even with the results, why are photons determined to be particles and waves at the same time, instead of particles that move in a wave pattern? In bodies ...
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Problems book recommendation on supersymmetry, supergravity and superstring theory

I'm learning supersymmetry, supergravity and superstring. I want some problems books to have some idea in this area. Is there this kind of books? Or are there some papers that have many solved model?
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Truncation of $D=5$, ${\cal N}=8$ Supergravity by $\mathbb Z_2^3$

The scalar manifold of $D=5, \mathcal N=8$ SUGRA is $$\mathcal M = \frac{E_{6(6)}}{Usp(8)}$$ where $USp(8)$ is a maximal compact subgroup of $E_{6(6)}$ and the 42 scalars of the theory correspond ...
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What is the relation between a $D_2$-brane and an $M2$-brane?

I am only familiar with the concept of a $D_2$-brane from a first course in String theory. I would like to learn, at least on a conceptual level, what an $M2$-brane is and what is its relation to the $...
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Why should fermions vanish for a solution of a supergravity theory that preserves supersymmetry?

On p.249 of Freedman and Van Proeyen's Supergravity, the following is stated: "Given the action of a supergravity theory, it is generally useful to search for solutions of the classical equations ...
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38 views

Einstein Field Equation for a Garfinkle-Horowitz-Strominger theory

When deriving the Einstein field equation from a theory with a dilaton field, we have: GHS's calculation However, in my calculation: My calculation So I found that GHS has missed $R$ and $(▽φ)^2$. ...
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Sources to learn about Killing spinors

What are some good sources to learn about Killing spinors from? I am currently learning about Killing vectors and how they are the generators of a Lie algebra that corresponds to the isometry group ...
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Correction to fermion mass in Supergravity mediated supersymmetry-breaking

I recently came across this paper about axino (fermion superparter of axion) mass in supergravity: https://doi.org/10.1016/0370-2693(92)90547-H In this paper, they think of a specific superpotential (...
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What is the high-energy/superstring analogue of wave function?

Chapter 12 of Beckers' book about superstrings and m-theory lists several deep dualities between low energy gauge theories and high energy superstring theories. I am only at the Chapter 2, that is why ...
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143 views

Problems with covariant action of the superstring

I was reading Kiritsis notes (http://arxiv.org/abs/hep-th/9709062), at page 105/106 (equation 10.1), where he has a covariant action of the superstring including the gravitino. I have problems showing ...
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Relationship between compactification moduli and generations in standard model

The situation I am describing is a $10D$ heterotic string theory which is compactified on a Calabi-Yau to get a $N=1$, $4D$ effective theory. It is mentioned in Ashoke Sen's notes on string ...
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Deriving Supergravity Equations of Motion

The other day I decided to quickly make sure I can derive the supergravity equations of motion for the NS/NS sector using the following action: $$ S=\int_{M_{10}}d^{10}x \space \sqrt{-g} e^{-2\phi}\...
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Understanding Moonshine via Heterotic E8xE8 (resubmitted, originally asked on mathematics stack exchange)

Recently I have become familiar with the conjectured relationship of monstrous moonshine and pure (2+1)-dimensional quantum gravity in AdS with maximally negative cosmological constant and, it’s being ...
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Maxwell-Chern-Simons equation: Translating from differential form to component form

I am trying to solve the scalar-coupled Maxwell-CS equations (which is one of the equation of motions in $N=2$ supergravity coupled to 3 vector multiplets), which is written in this form in the ...
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1answer
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What are the main physical consequences of supergravity?

String theory in some limit becomes supergravity. This is the super generalisation of gravity where instead of taking the Poincare symmetry as the local symmetry of spacetime we take the super-...
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Is the $\alpha'$ expansion in string theory an asymptotic expansion?

The low-energy bosonic effective actions of string theory lead to Einstein-Hilbert gravity, along with scalars and $p$-form Maxwell fields. For example, the action for type IIA string theory is $S = \...
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Can a metric in General Relativity, Supergravity, String Theory, etc., be asymmetric?

Why is it that all problems I encountered until now have metrics that when represented in a matrix form turn out to be symmetric? Aren't there asymmetric matrices representing some metrics?
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A generalized Veneziano formula for p-branes?

The rise of string theory as a theory of quantum gravity is in debt to G. Veneziano and his formula for the string scattering in terms of Euler beta function. Could a generalization of that formula, ...
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Towards a quantum maximal supergravity?

Is there any evidence of ultraviolet quantumness and well defined behaviour in eleven dimensional supergravity? Of course, since it is one limit of M-theory, I see no good review of this topic in the ...
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1answer
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Effective low energy actions in string cosmology

I wonder why can SUGRA actions be used in string cosmology, since in some cases they are used to model big bang scenarios (for example the pre big bang scenario in chapter 4 of Gasperini's "Elements ...
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What is a theory of gravity?

Let me introduce this question by noting that my training is in condensed matter physics, and my familiarity with gravity is superficial at best. Hence, this question may be somewhat naive. In ...
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Dual of Kalb Ramond field [closed]

i've been studying string theory for 4 days, i have a Kalb Ramond $B_{(2)}$ of this kind (from a $5^2 _2$ solution [1]) and i want evaluate its dual but i don't obtain the right result: The variables ...
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Can we gauge away curvature in supergravity?

In locally supersymmetric theories we can make a supertransformation which rotates one field into another. With enough supersymmetries could one not make a supertransformation at each point which made ...
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Are there any SUSY black holes in D > 5?

Quoting from arXiv:0801.3471 Asymptotically flat BPS black hole solutions are known only for $d = 4,\,5$. and I've seen this claim very timidly suggested in a couple of other places, but I couldn'...
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70 views

Constraint equation for Einstein-Hilbert action in Light-cone gauge

In Light cone coordinate system $(+,-,i)$, where $i=1,2$, the light cone coordinates are defined as $x^{\pm}=\frac{x^0 \pm x^3}{\sqrt{2}}$, if we consider the $+$ coordinate to be our "timelike" ...
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Would N=8 Supergravity solve quantum gravity if it was finite?

If N=8 Supergravity turned out to be finite to all loops in Feynman diagrams, would it be a complete theory of quantum gravity? Some people have said that a theory like loop quantum gravity is needed ...
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Do 11D SUGRA fields exist at the fundamental level of M theory?

The M branes in M theory are a configuration of the fields of 11D sugra, but sugra is a low energy limit of M theory. So do these fields exist at the fundamental level of the theory, and if not, what ...
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No-scale Kaehler potential in string theories

a) How does the no-scale Kaehler potential $$K=-3\log(T+\bar{T})$$ arise in string theory? b) And what are restrictions on matter couplings in such models? For instance, are we allowed to place ...
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D-brane worldvolume actions: Where are the Fermions?

I am studying D$p$-brane polarization (Myer's effect https://arxiv.org/abs/hep-th/9910053) and brane-flux annihilation (KPV mechanism, https://arxiv.org/abs/hep-th/0112197). There is little to no ...
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Anomalous curvature coupling corrections for $Dp$-branes worldvolume actions

The Chern-Simons term of an (abelian brane) is commonly written as $$ \sim\int_{\mathcal M_{p+1}}\sum_iC_{i}[e^{2\pi\alpha'F+B}], $$ where $C_i$ is the background Ramond-Ramond $i$-form, $F$ is the ...
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What is meant by the coupling term $g_{\mu\nu}T^{\mu\nu}$ in Supergravity?

In the "Cambridge Lectures on Supersymmetry and Extra Dimensions" of F.Quevedo it is written on page 59 ($T^{\mu\nu}$ stands for the energy-momentum tensor): The metric $g_{\mu\nu}$ as gauge field ...
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New-minimal vs old-minimal supergravity

New-minimal set of supergravity auxiliary fields includes a two-form field, whereas the old-minimal auxiliary set includes a vector and a complex scalar. Is anyone aware of how to transform between ...
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Fuzzy sphere of polarized D0 branes, non-abelian worldvolume action regime validity

I am studying Myer's paper "Dielectric Branes" (https://arxiv.org/abs/hep-th/9910053v2), where it is shown that a stack of D0 branes polarizes into a spherical D0-D2 bound state. The stack of $N$ D0 ...
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Supergravity Kahler-Weyl transformations

How can I find (finite) superfield Kahler-Weyl transformations of superspace spinorial differential operators (usually denoted $\mathcal{D}_\alpha$ and $\bar{\mathcal{D}}_\dot{\alpha}$) in ${\cal N}=1$...
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Why a Christoffel connection is inconsistent with local supersymmetry?

I'm doing an introductory studying on supergravity, and I'm studying in particular on the book Supergravity of D. Z. Freedman and A.V. Proeyen. In this book they describe supersymmetry using Majorana ...
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What is the current status of ${\cal N}=8$ Supergravity among physicists? [closed]

On April 24 2018, Z. Bern et al wrote this https://arxiv.org/abs/1804.09311 A conclusion of this paper is that the 5-loop four-point amplitude of ${\cal N}=8$ supergravity first diverges at $D = 24/5$...
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1answer
395 views

Action with self-dual field strength

It is said that writing down an action in presence of a self-dual field strength is subtle and not known till date. The familiar example people give is that of type IIB super-gravity which has a self-...
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112 views

$D=10$ Type IIB Supergravity action

In this review of SUSY gauge theories and the $AdS-CFT$ correspondence, on Page-29, firstly the Supergravity action for $D = 11$ is written. The authors then say that the action for the Type IIA ...
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1answer
104 views

Which extensions of the Standard model have the inflaton candidates?

Like dark matter and dark energy, there is no candidate of inflaton in the Standard Model (SM) of the particle physics but its various extension does have candidates of dark matter. Does the minimal ...
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1answer
56 views

Are there any flow to different dimension?

So far as I know from gauged supergravity there are studies of RG flows from the same dimension. Are there any flow to different dimension, i.e. flow from $AdS_5$ to $AdS_4$?
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Decomposition of $E_6$ into $SO(p,q)$

I've seen the following decomposition of the fundamental representation 27 of $E_6$ into $$E_6 \rightarrow SU(2) \times SO(5,2) \times SO(1,1)$$ $$27 \rightarrow (1,1)(-4) + (1,7)(-2) + (2,8)(+1) + ...
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Higher dimensional supergravity d.o.f

From where do the antisymmetric tensor d.o.f. arises from superpoincare group in 10 and 11 dimensional ${\cal N}=1$ SUGRAs? I mean, beyond the d.o.f. matching. Why it need's to be antisymmetric?
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686 views

Local translations in curved spacetime

A global Poincare transformation on a scalar field induces $$\delta(a, \lambda)\phi(x) = [a^{\mu}+\lambda^{\mu\nu}x_{\nu}]\partial_{\mu}\phi(x). \tag{11.46}$$ In curved spacetime we replace $a^{\mu} ...
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1answer
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Is there a simple way to understand why SUGRA is two-loop renormalisable?

Naïve quantum gravity is one-loop renormalisable. There is a very simple way to argue that this is true: one lists all possible counter-terms that may appear at one loop, and shows that they are, up ...
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Does 4D ${\cal N} = 3$ supersymmetry exist?

Steven Weinberg's book "The Quantum Theory of Fields", volume 3, page 46 gives the following argument against ${\cal N} = 3$ supersymmetry: "For global ${\cal N} = 4$ supersymmetry there is just ...
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1answer
256 views

How does 11D Supergravity relate to M-Theory?

I know Type IIA/B, Type I, HO, & HE are related through the T and S Dualities. However, how does SUGRA factor in here? What exactly is 11D SUGRA’s significance in M-Theory? Some seem to suggest ...