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S^3 and S^4 Reductions of Type IIA Supergravity

High Energy Physics - Theory · Submitted 15 May 2000 · 31 references

Pith's verdict: A real new result — full SO(4) S^3 reduction of IIA — built by inheritance from the S^4 reduction, with the announced direct check left undone.

T0 · AI review

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arXiv IDhep-th/0005137 (version 2)
Pith IDDCY2LQVS, Pith's permanent record of this paper and its review
CitationA. Sadrzadeh, C.N. Pope, H. Lu, M. Cvetic, T.A. Tran. "S^3 and S^4 Reductions of Type IIA Supergravity." arXiv:hep-th/0005137 (2000). https://pith.science/paper/DCY2LQVS
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Referee report
The paper

The paper claims

The paper claims that type IIA supergravity can be consistently reduced on a 3-sphere while retaining the full SO(4) Yang-Mills gauge group, yielding a maximal gauged supergravity in seven dimensions.

The reading

The paper sets out to show that ten-dimensional type IIA supergravity admits a consistent Kaluza-Klein reduction on $S^3$ that keeps the entire $SO(4)$ isometry group as massless Yang-Mills gauge fields. The payoff would be a maximal seven-dimensional gauged supergravity whose most symmetric ground state is a domain wall rather than anti-de Sitter space. The authors do not prove this from scratch; they obtain it as a singular scaling limit of the known $S^4$ reduction of eleven-dimensional supergravity, in which the internal 4-sphere degenerates to $mathbb{R}times S^3$. They also construct the parallel $S^4$ reduction of type IIA to six dimensions, giving an $SO(5)$-gauged maximal theory.

What carries the argument

The mechanism carrying the argument is a matched rescaling of the seven-dimensional fields and of the internal $S^4$ coordinates. The scaling sends $mu^0to0$ and leaves $mu^alpha$ on a unit $S^3$, while the gauge coupling and gauge fields are rescaled so that an $SO(4)$ subgroup survives. This turns the $SO(5)$-gauged equations into $SO(4)$-gauged equations with no singular terms, and it turns the eleven-dimensional $S^4$ Ansatz into an $S^3$ reduction Ansatz for type IIA. For the separate $S^4$ reduction of type IIA, the key technical step is completing the square in the eleven-dimensional metric after a circle reduction, which produces the ten-dimensional dilaton, metric, and one-form Ansatz in terms of six-dimensional fields and axions.

Extended reading notes

Core claim

The central claim is that type IIA supergravity admits a consistent reduction on $S^3$ in which the whole $SO(4)simeq SU(2)_Ltimes SU(2)_R$ isometry is gauged, not merely one $SU(2)$. The authors obtain it by starting from the $S^4$ reduction of eleven-dimensional supergravity and taking a singular limit of the resulting seven-dimensional $SO(5)$-gauged theory: split the index as $i=(0,alpha)$, scale $g=lambda^2 tilde g$, $A^{0alpha}=lambda^3 tilde A^{0alpha}$, $A^{alphabeta}=lambda^{-2}tilde A^{alphabeta}$, and scale the internal coordinate as $mu^0=lambda^5 tilde mu^0$ with $mu^alpha=tilde mu^alpha$. As $lambdato0$ the constraint $mu^i mu^i=1$ becomes $tilde mu^alpha tilde mu^alpha=1$, so the internal $S^4$ degenerates to $mathbb{R}times S^3$; the seven-dimensional equations have a smooth $SO(4)$-gauged limit even though the Lagrangian does not. Reading the same limit in eleven dimensions gives the $S^3$ reduction Ansatz for the type IIA metric, dilaton, one-form, and form fields. The paper also performs the non-singular $S^4$ reduction of type IIA to a six-dimensional $SO(5)$-gauged maximal supergravity.

Load-bearing premise

The load-bearing premise is that the starting 4-sphere reduction of eleven-dimensional supergravity is genuinely consistent, including in the eleven-dimensional Einstein equation and beyond the approximation that drops quartic fermion terms.

Editorial extensions

If this is right

  • If the reduction is consistent, every solution of the seven-dimensional $SO(4)$-gauged equations lifts to a configuration of type IIA supergravity.
  • The seven-dimensional theory is maximal and has a domain-wall ground state, so it provides a setting for domain-wall/QFT correspondence rather than standard AdS/CFT.
  • The parallel $S^4$ reduction gives an $SO(5)$-gauged maximal supergravity in six dimensions.
  • The construction adds an example of a sphere reduction whose consistency has no known group-theoretic explanation, sharpening the question of why such reductions work.

Reading between the lines

Editorial extensions of the paper, not claims the author makes directly.

  • If the construction holds, the next natural check is whether the seven-dimensional domain-wall solutions and their scalar fluctuations reproduce the expected Coulomb-branch behavior of the dual quantum field theory beyond the Cartan subsector.
  • The axion-dependent metric Ansatz in (64)-(67) suggests a general recipe for completing the square in other sphere reductions that involve vector axions.
  • An independent verification of the eleven-dimensional Einstein equation for the starting $S^4$ Ansatz would settle both the seven-dimensional and six-dimensional claims at once.
Original abstract

We construct a consistent reduction of type IIA supergravity on S^3, leading to a maximal gauged supergravity in seven dimensions with the full set of massless SO(4) Yang-Mills fields. We do this by starting with the known S^4 reduction of eleven-dimensional supergravity, and showing that it is possible to take a singular limit of the resulting standard SO(5)-gauged maximal supergravity in seven dimensions, whose eleven-dimensional interpretation involves taking a limit where the internal 4-sphere degenerates to RxS^3. This allows us to reinterpret the limiting SO(4)-gauged theory in seven dimensions as the S^3 reduction of type IIA supergravity. We also obtain the consistent S^4 reduction of type IIA supergravity, which gives an SO(5)-gauged maximal supergravity in D=6.

The compiled record

The paper's own sentences, arranged, kept beside the review and separate from it. Each label is drawn from a closed vocabulary; the number beside it is the probability the classifier gave that label. Numbers in the tables are the authors', checked by code. No sentence in this record was written by a model.

Compiled by classifier-1.13-20260917 via OpenRouter, question bank abstract-p1-20260923, 2026-09-23: 1 request, 3,778 input tokens, $0.0002 reported.

What the abstract itself states, as probabilities: claims first 0.05 · states limitation 0.10 · human participants 0.01 · controlled comparison 0.01 · randomized assignment 0.01 · states quantitative result 0.23 · compares with prior results 0.81 · mentions code or data availability 0.01.

The abstract, sentence by sentence

arXiv listing abstract v2. Results and the main claim are underlined; .

We construct a consistent reduction of type IIA supergravity on S^3, leading to a maximal gauged supergravity in seven dimensions with the full set of massless SO(4) Yang-Mills fields. We do this by starting with the known S^4 reduction of eleven-dimensional supergravity, and showing that it is possible to take a singular limit of the resulting standard SO(5)-gauged maximal supergravity in seven dimensions, whose eleven-dimensional interpretation involves taking a limit where the internal 4-sphere degenerates to RxS^3. This allows us to reinterpret the limiting SO(4)-gauged theory in seven dimensions as the S^3 reduction of type IIA supergravity. We also obtain the consistent S^4 reduction of type IIA supergravity, which gives an SO(5)-gauged maximal supergravity in D=6.

background contribution method result interpretation main claim

What the classifier reports for each sentence. The number is the probability it gave the label.
#sentencerolethe authors' own workstates the main conclusionstrength
s0 We construct a consistent reduction of type IIA supergravity on S^3, leading to a maximal gauged supergravity in seven dimensions with the full set of massless SO(4) Yang-Mills fields. contribution 0.78 0.96 0.77 asserted 1.00
s1 We do this by starting with the known S^4 reduction of eleven-dimensional supergravity, and showing that it is possible to take a singular limit of the resulting standard SO(5)-gauged maximal supergravity in seven dimensions, whose eleven-dimensional interpretation involves taking a limit where the internal 4-sphere degenerates to RxS^3. method 1.00 0.84 0.11 asserted 0.67
s2 This allows us to reinterpret the limiting SO(4)-gauged theory in seven dimensions as the S^3 reduction of type IIA supergravity. interpretation 0.99 0.87 0.30 asserted 0.97
s3 We also obtain the consistent S^4 reduction of type IIA supergravity, which gives an SO(5)-gauged maximal supergravity in D=6. result 0.57 0.94 0.17 asserted 1.00

What kind of paper the classifier reports this is: theoretical result 1.00 · evidence from proof or derivation 0.99.

What was examined, and what was not

sources read
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  • figures and tables
  • references and citing sentences
  • relations to other papers
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not run
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  • T body sentences
  • C citations
  • R cross-paper relations

Every quoted sentence on this record is the authors'. Every label is from Pith's closed vocabulary, with the probability shown beside it. Every number in the measurements table is the authors', checked by code. Record as JSON

References
How the literature uses it

37 arXiv papers cite this in 83 sentences

Each citing sentence is taken from the citing paper's LaTeX source and typed by Pith's classifier. A label appears at probability 0.8 or more (0.95 for support), a contest at 0.7 or more; the quoted words are the citing authors'. How each label was checked · JSON

Papers citing it · 48 sentences without a confident label

Contests it 1 paper
  • The equations of motion for $D=7$ gauged supergravity arising from [ref] are given by [equation] and [equation] where [equation] We note that a typo in [ref] has been fixed in the last equation of [ref].

    Consistent KK truncations for M5-branes wrapped on Riemann surfaces · Equations of motion of $D=7$ gauged supergravity · contest 0.87

Builds on it 1 paper
  • Moreover, our derivation clarifies longstanding technical issues encountered in consistent Kaluza-Klein reductions on spheres and offers a general formalism that complements and extends the results found in prior literature such as [ref] .

    Hodge Duals in Spherical Compactifications · Conclusion · 0.93

Uses its method or tool 11 papers
  • Using the uplift formulas of [ref] one finds that the ten-dimensional solution in the string frame can be written as 10dsolNSNS _10 =(^1,5)+^2Φ[∑_i=1^4(^-2f_i(μ_i)^2)s^2 s^2+∑_i=1^4(^2f_i(μ_i)^2)] , H_3 =-2⋆[Φ∧(^1,5)] , ^2Φ =16/g^2∏_i=1^4^-f_i/∑_i=1^4(^-2f_i(μ_i)^2) , where $∑_i(μ_i)^2=1$ hence the $μ_i$ parametrize $S^3⊂^4$.

    On Supergravity and Noncritical Strings · Distributions of NS5 branes from 7d · 0.97

  • Here we need to introduce $μ^a$, $a=1,…,4$ as constrained coordinates on the $S^3$, $δ_ab μ^a μ^b= 1$, a unit determinant symmetric matrix[Note that what we call $M_ab$ is denoted $M^-1_αβ$ in [ref] .] $M_ab$ with inverse $M^ab$, and define [equation] Then the ansatz is [equation] where $D μ^a ≡dμ^a + g A_(1)^ab μ^b$, $D M^ab = d M^ab + 2 g A_(1)^(a|c M^c|b)$ and $F_(2)^ab = d A_(1)^ab +g A_(1)^ac ∧A_(1)^cb$.

    Generalised U-dual solutions in supergravity · $CSO(4,0,1)$ from IIA on $S^3$ · 0.94

  • In this work, we will mainly consider uplifted solutions from these two gauge groups using the truncation ansatze given in [ref] which are more useful for solutions involving two- and three-form fields in seven dimensions.

    Supersymmetric solutions of 7D maximal gauged supergravity · Introduction · 1.00

Compares with it 1 paper
  • Instead, let us investigate the relationship to the known $CSO(4,0,1)$ gauging arising from reduction of type IIA on $S^3$, or 11-dimensional supergravity on $ℝ×S^3$ [ref] .

    Exploring Exceptional Drinfeld Geometries · Relationship to IIA on $S^3$ · 0.80

Cites it as support 1 paper
  • On the other hand, all of the supersymmetry is manifest in the frame $$, and reducing 10d supergravity on $S^3$ does indeed give rise to a supergravity in 7d [ref] .

    On Supergravity and Noncritical Strings · The 7d supergravity · 0.97

Cites it as background 10 papers
  • The relationship between $= (1,0)$ supergravity coupled to one anti-self-dual tensor multiplet in six dimensions and the three-dimensional $4$, $SO(4,4)$ supergravity (with $n=1$) has been laid out in [ref] .

    Microstate Geometries from Gauged Supergravity in Three Dimensions · Some supergravity background · 0.80

  • The classical examples of Scherk-Schwartz reductions [ref] on local group manifolds [ref] , together with the exceptional consistent truncations on spheres [ref] were unified as generalised Scherk-Schwartz reductions[For other examples of the use of generalised geometry and exceptional field theory in the context of generalised Scherk-Schwartz reductions, see [ref] . ] in [ref] using the language of generalised geometry.

    Adjoint orbits, generalised parallelisable spaces and consistent truncations · Introduction · 0.94

  • Generic consistent $S^3$ truncations in (super)gravity have been discussed in [ref] , where the full non-linear Kaluza-Klein Ansätze were constructed for a higher-dimensional theory that comprises the field content of the bosonic string.

    Consistent $S^3$ reductions of six-dimensional supergravity · Introduction · 0.80

Discussion

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