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Stringy Schroedinger truncations

High Energy Physics - Theory · Submitted 30 Dec 2012 · 71 references

Pith's verdict: A solid, honest construction paper: the four-parameter warped black string family and the four consistent truncations are real and checked, and the stability claim is properly hedged rather than oversold.

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arXiv ID1212.6792 (version 1)
Pith IDLFK3PEJ7, Pith's permanent record of this paper and its review
CitationMonica Guica, Stephane Detournay. "Stringy Schroedinger truncations." arXiv:1212.6792 (2012). https://pith.science/paper/LFK3PEJ7
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The paper

The paper claims

Type IIB supergravity admits a four-parameter family of warped black strings whose thermodynamics and asymptotic symmetries match BTZ, and whose three-dimensional truncations contain Schroedinger vacua plus black holes.

The reading

Three-dimensional Schroedinger spacetimes are gravity duals of non-relativistic conformal field theories, and they appear in the Kerr/CFT proposal for extremal black holes. A long-standing obstacle is that the simplest models with Schroedinger solutions, such as Einstein gravity coupled to a massive vector, contain no known black holes. Without black holes one cannot test finite-temperature holography or derive the entropy from a Cardy-like formula. This paper addresses that gap inside string theory. Starting from the near-horizon D1-D5 black string of type IIB supergravity, the authors apply two generalized spectral flow transformations, each a sequence of T-dualities and S-dualities with a shift, followed by an infinite boost. The result is a four-parameter family of warped black string solutions, labeled by left and right temperatures and two deformation parameters. The authors then reduce type IIB on a squashed three-sphere and show that the six-dimensional equations of motion are automatically solved by solutions of a three-dimensional action, so the truncation is consistent. Four such truncations are given, with different field content. The black strings turn out to have thermodynamics and asymptotic symmetry data that match BTZ in a suitable parametrization, independent of the deformation parameters. The linearized spectrum around the Schroedinger vacua, computed inside the truncations, contains modes with imaginary radial falloff, analogous to fields below the Breitenlohner-Freedman bound. The authors argue, from a zero-flux boundary condition, that these modes do not produce a linear instability, though they flag that the analysis is preliminary and that the allowed frequencies are unbounded below.
Extended reading notes

Core claim

The paper claims two things: (i) a four-parameter family of warped black string solutions of type IIB supergravity, generated by two generalized spectral flows applied to the near-extremal D1-D5 string, whose mass, momentum, entropy and asymptotic symmetry data equal those of BTZ in an appropriate parametrization (Eqs. 3.24-3.25, 3.28-3.30); and (ii) the first consistent truncations of type IIB to three dimensions that admit both supersymmetric Schroedinger solutions and warped BTZ generalizations (actions 4.7, 4.17, 4.20, 4.26). If correct, finite-temperature Schroedinger holography acquires a string-theoretic toy model with black holes.

Load-bearing premise

The stability conclusion in Sec. 5.3 rests on the assumption that a linearized analysis in global Schroedinger coordinates, with a zero-flux boundary condition at rho = 0, correctly diagnoses stability. The authors themselves note in Sec. 6 that the coordinates used are the analogue of null coordinates in AdS, where a Breitenlohner-Freedman instability is not immediately visible, and that a non-linear analysis is still needed. They also find the allowed frequencies are unbounded below and depend on an arbitrary constant gamma_+ (Fig. 4). If the null-coordinate analysis hides an instability, the abstract's claim that these modes do not destabilize the vacuum fails.

Original abstract

Motivated by the desire to better understand finite-temperature holography for three-dimensional Schroedinger spacetimes, we: i) construct a four-parameter family of warped black string solutions of type IIB supergravity and ii) find the first consistent truncations of type IIB string theory to three dimensions that admit both supersymmetric Schroedinger solutions and warped generalizations of the BTZ black hole. Our analysis reveals a number of interesting features. One is that the thermodynamic properties of all the warped black strings, as well as the asymptotic symmetry group data, are identical to those of BTZ, in an appropriate parametrization. A more striking feature is that the spectrum of linearized perturbations around the various supersymmetric Schroedinger vacua oftentimes contains modes that carry energy flux through the spacetime boundary, which are usually believed to be unstable. A preliminary analysis indicates that, at least in the case of most interest, these modes do not lead to an instability.

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, 4,423 input tokens, $0.0002 reported.

What the abstract itself states, as probabilities: claims first 0.84 · states limitation 0.76 · human participants 0.01 · controlled comparison 0.08 · randomized assignment 0.01 · states quantitative result 0.22 · compares with prior results 0.43 · mentions code or data availability 0.02.

The abstract, sentence by sentence

arXiv listing abstract v1. Results and the main claim are underlined; .

Motivated by the desire to better understand finite-temperature holography for three-dimensional Schroedinger spacetimes, we: i) construct a four-parameter family of warped black string solutions of type IIB supergravity and ii) find the first consistent truncations of type IIB string theory to three dimensions that admit both supersymmetric Schroedinger solutions and warped generalizations of the BTZ black hole. Our analysis reveals a number of interesting features. One is that the thermodynamic properties of all the warped black strings, as well as the asymptotic symmetry group data, are identical to those of BTZ, in an appropriate parametrization. A more striking feature is that the spectrum of linearized perturbations around the various supersymmetric Schroedinger vacua oftentimes contains modes that carry energy flux through the spacetime boundary, which are usually believed to be unstable. A preliminary analysis indicates that, at least in the case of most interest, these modes do not lead to an instability.

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 Motivated by the desire to better understand finite-temperature holography for three-dimensional Schroedinger spacetimes, we: i) construct a four-parameter family of warped black string solutions of type IIB supergravity and ii) find the first consistent truncations of type IIB string theory to three dimensions that admit both supersymmetric Schroedinger solutions and warped generalizations of the BTZ black hole. contribution 1.00 0.97 0.37 asserted 1.00
s1 Our analysis reveals a number of interesting features. result 0.49 0.43 0.02 asserted 0.58
s2 One is that the thermodynamic properties of all the warped black strings, as well as the asymptotic symmetry group data, are identical to those of BTZ, in an appropriate parametrization. result 1.00 0.89 0.14 asserted 1.00
s3 A more striking feature is that the spectrum of linearized perturbations around the various supersymmetric Schroedinger vacua oftentimes contains modes that carry energy flux through the spacetime boundary, which are usually believed to be unstable. result 0.99 0.89 0.13 asserted 0.93
s4 A preliminary analysis indicates that, at least in the case of most interest, these modes do not lead to an instability. result 0.65 0.91 0.23 hedged possibility 1.00

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

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sources read
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not examined
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  • figures and tables
  • references and citing sentences
  • relations to other papers
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  • T body sentences
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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

Figures
Figure 1. Plot of the four sk as a function of λκ. Each solution can be identified by its value at λκ = 0. Note that s2 and s3 cross over at λκ = √ 3 2 . The usual dipole truncation The usual dipole truncation (4.7) describes four propagating degrees of freedom: two scalars, U and φ, and one massive vector Aˆ. Therefore, we expect to obtain an eighth order differential equation. Nevertheless, it turns out that at least at linearized level the scalars φ and χ ≡ 2U + φ decouple, and each obeys a fourth order differential equation. These equations turn out to be identical to (5.13). Thus, the s
Figure 2. Left: plot of the four βi as a function of x = λκ; Right: zoom near λκ = 0 in β1. Interestingly, the eigth order differential equation we have started from can be reduced to four independent second order differential equations, all of which take the form ρ 2 g ′′(ρ) +  1 4 − βi − 1 2 ρωκ g(ρ) = 0 (5.20) where βi are the four solutions to (5.17). This simplification implies that we can find the exact solution to the equations of motion in the entire spacetime, not just asymptotically, which will be of great use for the stability analysis of the next subsection. The general t
Figure 3. The region in the α − x plane where the weight equation has imaginary eigenvalues. Note that the graph is symmetric about the α = 1 2 line. The upper dotted line represents S-dual dipole theories (α = 1), where the range of imaginary weights has shrunk to zero size, yielding the crossover behaviour in
Figure 4. The spectrum of allowed ω for κ > 0 is given by the intersection of the phase function γη(ω), plotted in blue above, with the constant line γ = γ+, plotted in red. The spectrum of allowed frequencies that we have obtained is identical to that obtained in [42] for a probe scalar field propagating in the global Schr¨odinger background. While the specific couplings in the truncated Lagrangian were extremely important in determining that travelling wave solutions exist, the behaviour of these solutions seems rather universal, and depends on the particular couplings only through the…

Figures reproduced from arXiv:1212.6792 by the authors.

References
How the literature uses it

36 arXiv papers cite this in 113 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 · 73 sentences without a confident label

Builds on it 2 papers
  • In this note, we propose an extension of the dictionary in [ref] to a family of warped AdS$_3$ black string solutions in string theory found in [ref] .

    Decrypting the warped black strings · Introduction · 1.00

  • In section [ref], we generalise the KK reductions discussed in [ref] and identify the corresponding gauged supergravities.

    3D Supergravity from wrapped D3-branes · Introduction · 0.98

Uses its method or tool 1 paper
  • As such, we adopt the same strategy as [ref] , but an important distinction is that we will not impose truncations directly in six dimensions and then reduce.

    3D Supergravity from wrapped D3-branes · Intersecting D3-branes · 0.85

Uses its data or values 2 papers
Compares with it 4 papers
  • It is not hard to show that $Q_τ$ and $Q_x$ per unit $x$-length equal precisely the energy and momentum per unit length of the string [ref], which were computed in [ref] using covariant methods.

    Decrypting the warped black strings · The holographic stress tensor · 0.95

  • We can now compare this directly to the reduction Ansatz considered in [ref] (which is based on [ref] ) leading to the three-dimensional Einstein frame metric s^2_3 = 4 r^4 [ -(t + μx)^2 + Z_1 Z_2 Z_3 (x^2 + r^2) ].

    SUSY properties of warped AdS$_3$ · Supertube solutions · 0.91

  • Both theories admit supersymmetric Schrödinger solutions, however, for those based on the D1-D5 near-horizon [ref] the dynamical exponent $z=2$ appears, while the dynamical exponent quoted in [ref] is $z=4$.

    3D Supergravity from wrapped D3-branes · Connection between CITEMARK179Z and CITEMARK180Z · 0.97

Cites it as background 14 papers
  • In section [ref], we review the holographic proposal of [ref] for three-dimensional Schrödinger spacetimes, as well as the simplest warped black string solution of [ref] .

    Decrypting the warped black strings · Introduction · 0.88

  • In section [ref], we review two of the consistent truncations of [ref] that we will work with, as well as the covariant phase space formalism.

    Two Virasoro symmetries in stringy warped AdS$_3$ · Introduction · 0.83

  • The holographic realization of WCFTs is naturally formulated in three–spacetime dimensions, and it has followed three main routes[Other holographic approaches realizing the Virasoro–Kac–Moody algebra include [ref] ]: notably in the context of warped AdS$_3$ black holes in topologically massive gravity [ref] ; the so called “lower-spin gravity” [ref] , formulated as a Chern–Simons theory of $SL(2,ℝ)×U(1)$; and General Relativity (GR) on AdS$_3$ with the boundary conditions of Compere, Song and Strominger (CSS) [ref] .

    Holographic warped CFTs from General Relativity on AdS$_3$ · Introduction · 0.94

What it cites · 84 sentences without a confident label

Builds on 2 papers
Uses the method or tool of 7 papers
Compares with 7 papers
Cites as support 6 papers
  • Luckily, there are some indications in the literature [ref] , that fields below the Schrödinger analogue of the Breitenlohner-Friedman bound may in fact not destabilize the vacuum.

    Below the Breitenlohner-Freedman bound in the nonrelativistic AdS/CFT correspondence · Comments on stability · 1.00

  • It has been explicitly checked in [ref] that the corresponding Schrödinger background carries this amount of supersymmetry.

    Kerr/CFT, dipole theories and nonrelativistic CFTs · Supersymmetry and cases of interest · 0.96

  • Despite this, the evidence in favour of this conjecture seemed plentiful: the presence of a Virasoro symmetry that enhances the $U(1)$ isometry factor, the precise agreement of the Bekenstein-Hawking entropy of the black hole with the Cardy entropy of the putative dual CFT, the striking resemblance between scattering amplitudes off the black hole and thermal CFT Green's functions [ref] .

    Black Hole Superradiance From Kerr/CFT · Introduction · 0.98

Cites as background 14 papers

Discussion

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