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arxiv: 2411.11096 · v1 · submitted 2024-11-17 · ✦ hep-th · gr-qc

An extremal black hole with a unique ground state

Pith reviewed 2026-05-23 08:37 UTC · model grok-4.3

classification ✦ hep-th gr-qc
keywords extremalstateblackgrounddescriptionenergyholesnon-supersymmetric
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The pith

Microscopic D-brane description of non-supersymmetric extremal black holes yields a unique ground state with non-zero energy, confirming absence of degeneracy.

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

Extremal black holes sit at the edge of the allowed mass-charge relation. When supersymmetry is absent, string theory models them with four stacks of D-branes wrapping cycles on a six-torus and intersecting at one point. The authors write the low-energy worldline theory for this configuration. It contains 32 Goldstinos from completely broken supersymmetry and 28 Goldstones from broken translations. The resulting quantum Hamiltonian is then diagonalized. Its lowest-energy eigenstate is unique and has strictly positive energy, so no state sits exactly at the extremal bound.

Core claim

The Hamiltonian has a unique ground state, which carries a non-zero energy implying the absence of any truly extremal state.

Load-bearing premise

The low-energy worldline Lagrangian constructed from the four D-brane stacks with the stated orientations and intersection accurately captures the full dynamics without higher-order corrections or additional light modes that could alter the ground-state count.

read the original abstract

Recent computations in gravity suggest that non-supersymmetric extremal black holes lack any sizeable ground state degeneracy. We confirm this for D-brane description of non-supersymmetric 4-charge extremal black holes in N=8 string theory. The microscopic description comprises four stacks of D-branes wrapping various cycles of the internal six-torus and intersecting at a point. The orientations of the stacks are such that supersymmetry is broken completely. We construct the low energy worldline Lagrangian for the brane system, which is seen to have 32 Goldstinos and 28 Goldstones. The Hamiltonian has a unique ground state, which carries a non-zero energy implying the absence of any truly extremal state.

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, simulated authors' rebuttal, and a circularity audit. Tearing a paper down is the easy half of reading it; the pith above is the substance, this is the friction.

Referee Report

2 major / 1 minor

Summary. The manuscript claims that non-supersymmetric 4-charge extremal black holes in N=8 string theory, realized microscopically by four D-brane stacks with orientations that break all supersymmetry, admit a low-energy worldline Lagrangian containing 32 Goldstinos and 28 Goldstones. The associated Hamiltonian is asserted to possess a unique ground state carrying strictly positive energy, implying the absence of any truly extremal (zero-energy) state and thereby confirming recent gravity-based indications of vanishing ground-state degeneracy.

Significance. If the Hamiltonian analysis holds, the result supplies a concrete microscopic confirmation, using standard D-brane constructions without fitted parameters, of the absence of degeneracy for non-supersymmetric extremal black holes. This strengthens the broader program linking gravity computations to string-theory microstate counting and provides a falsifiable prediction that the effective 0+1-dimensional theory has no zero-energy vacuum.

major comments (2)
  1. [Abstract / low-energy worldline Lagrangian construction] The central claim rests on the assertion that the constructed worldline Lagrangian encodes precisely the 32 Goldstinos + 28 Goldstones with no additional light modes or relevant higher-order operators that could lift or degenerate the ground state. No explicit form of the Lagrangian, interaction terms, or derivation of the mode count is supplied, so it is impossible to verify that the truncation is reliable at the scale set by the brane charges (see the skeptic's weakest assumption).
  2. [Abstract / Hamiltonian analysis] The statement that 'the Hamiltonian has a unique ground state' with E > 0 is load-bearing for the conclusion that no truly extremal state exists, yet no explicit Hamiltonian, spectrum computation, or uniqueness proof is provided. Without these steps the claim cannot be checked and the link to the gravity computations remains unverified.
minor comments (1)
  1. [Abstract] The abstract is unusually dense and would benefit from a single sentence clarifying the four brane stacks and their wrapping cycles before stating the Goldstino/Goldstone count.

Axiom & Free-Parameter Ledger

0 free parameters · 1 axioms · 0 invented entities

The central claim rests on the domain assumption that the low-energy worldline theory for the chosen D-brane orientations correctly encodes the full spectrum of light modes and that the resulting Hamiltonian is the correct effective description.

axioms (1)
  • domain assumption The low-energy effective theory of the four intersecting D-brane stacks is given by a worldline Lagrangian containing exactly 32 Goldstinos and 28 Goldstones.
    Invoked in the abstract as the starting point for the Hamiltonian analysis.

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Reference graph

Works this paper leans on

53 extracted references · 53 canonical work pages · 42 internal anchors

  1. [1]

    D. N. Page, Thermodynamics of near extreme black holes , 9, 2000. hep-th/0012020

  2. [2]

    Preskill, P

    J. Preskill, P. Schwarz, A. D. Shapere, S. Trivedi and F. W ilczek, Limitations on the statistical description of black holes , Mod. Phys. Lett. A 6 (1991) 2353–2362

  3. [3]

    J. M. Maldacena, J. Michelson and A. Strominger, Anti-de Sitter fragmentation , JHEP 02 (1999) 011, [ hep-th/9812073]

  4. [4]

    L. V. Iliesiu and G. J. Turiaci, The statistical mechanics of near-extremal black holes , JHEP 05 (2021) 145, [ 2003.02860]

  5. [5]

    https://online.kitp.ucsb.edu/online/entangled15/kitaev/

    A. Kitaev, “ https://online.kitp.ucsb.edu/online/entangled15/kitaev/.”

  6. [6]

    https://online.kitp.ucsb.edu/online/entangled15/kitaev2/

    A. Kitaev, “ https://online.kitp.ucsb.edu/online/entangled15/kitaev2/.” – 11 –

  7. [7]

    Comments on the Sachdev-Ye-Kitaev model

    J. Maldacena and D. Stanford, Remarks on the Sachdev-Ye-Kitaev model , Phys. Rev. D 94 (2016) 106002, [ 1604.07818]

  8. [8]

    Conformal symmetry and its breaking in two dimensional Nearly Anti-de-Sitter space

    J. Maldacena, D. Stanford and Z. Yang, Conformal symmetry and its breaking in two dimensional Nearly Anti-de-Sitter space , PTEP 2016 (2016) 12C104, [ 1606.01857]

  9. [9]

    An Investigation of AdS$_2$ Backreaction and Holography

    J. Engels¨ oy, T. G. Mertens and H. Verlinde, An investigation of AdS 2 backreaction and holography, JHEP 07 (2016) 139, [ 1606.03438]

  10. [10]

    Fermionic Localization of the Schwarzian Theory

    D. Stanford and E. Witten, Fermionic Localization of the Schwarzian Theory , JHEP 10 (2017) 008, [ 1703.04612]

  11. [11]

    T. G. Mertens, G. J. Turiaci and H. L. Verlinde, Solving the Schwarzian via the Conformal Bootstrap, JHEP 08 (2017) 136, [ 1705.08408]

  12. [12]

    H. T. Lam, T. G. Mertens, G. J. Turiaci and H. Verlinde, Shockwave S-matrix from Schwarzian Quantum Mechanics , JHEP 11 (2018) 182, [ 1804.09834]

  13. [13]

    Statistical mechanics of a two-dimensional black hole

    A. Kitaev and S. J. Suh, Statistical mechanics of a two-dimensional black hole , JHEP 05 (2019) 198, [ 1808.07032]

  14. [14]

    Yang,The Quantum Gravity Dynamics of Near Extremal Black Holes,JHEP05 (2019) 205 [1809.08647]

    Z. Yang, The Quantum Gravity Dynamics of Near Extremal Black Holes , JHEP 05 (2019) 205, [ 1809.08647]

  15. [15]

    P. Saad, S. H. Shenker and D. Stanford, JT gravity as a matrix integral , 1903.11115

  16. [16]

    L. V. Iliesiu, S. S. Pufu, H. Verlinde and Y. Wang, An exact quantization of Jackiw-Teitelboim gravity, JHEP 11 (2019) 091, [ 1905.02726]

  17. [17]

    Choi and F

    S. Choi and F. Larsen, Effective Field Theory of Quantum Black Holes . 8, 2021. 2108.04028

  18. [18]

    Choi and F

    S. Choi and F. Larsen, AdS2 Holography and Effective QFT , 2302.13917

  19. [19]

    Ghosh, H

    A. Ghosh, H. Maxfield and G. J. Turiaci, A universal Schwarzian sector in two-dimensional conformal field theories , JHEP 05 (2020) 104, [ 1912.07654]

  20. [20]

    Mondal, Statistical Mechanics of Exponentially Many Low Lying State s, 2310.12264

    S. Mondal, Statistical Mechanics of Exponentially Many Low Lying State s, 2310.12264

  21. [21]

    Microscopic Origin of the Bekenstein-Hawking Entropy

    A. Strominger and C. Vafa, Microscopic origin of the Bekenstein-Hawking entropy , Phys. Lett. B 379 (1996) 99–104, [ hep-th/9601029]

  22. [22]

    J. M. Maldacena, A. Strominger and E. Witten, Black hole entropy in M theory , JHEP 12 (1997) 002, [ hep-th/9711053]

  23. [23]

    J. C. Breckenridge, D. A. Lowe, R. C. Myers, A. W. Peet, A. Strominger and C. Vafa, Macroscopic and microscopic entropy of near extremal spinn ing black holes , Phys. Lett. B 381 (1996) 423–426, [ hep-th/9603078]

  24. [24]

    J. M. Maldacena, D-branes and near extremal black holes at low-energies , Phys. Rev. D 55 (1997) 7645–7650, [ hep-th/9611125]

  25. [25]

    G. T. Horowitz, J. M. Maldacena and A. Strominger, Nonextremal black hole microstates and U duality , Phys. Lett. B 383 (1996) 151–159, [ hep-th/9603109]. – 12 –

  26. [26]

    Microscopic derivation of the Bekenstein-Hawking entropy formula for non-extremal black holes

    K. Sfetsos and K. Skenderis, Microscopic derivation of the Bekenstein-Hawking entropy formula for nonextremal black holes , Nucl. Phys. B 517 (1998) 179–204, [ hep-th/9711138]

  27. [27]

    J. M. Maldacena, Probing near extremal black holes with D-branes , Phys. Rev. D 57 (1998) 3736–3741, [ hep-th/9705053]

  28. [28]

    J. M. Maldacena, Statistical entropy of near extremal five-branes , Nucl. Phys. B 477 (1996) 168–174, [ hep-th/9605016]

  29. [29]

    G. T. Horowitz, D. A. Lowe and J. M. Maldacena, Statistical entropy of nonextremal four-dimensional black holes and U duality , Phys. Rev. Lett. 77 (1996) 430–433, [hep-th/9603195]

  30. [30]

    Microstates of Non-supersymmetric Black Holes

    A. Dabholkar, Microstates of nonsupersymmetric black holes , Phys. Lett. B 402 (1997) 53–58, [hep-th/9702050]

  31. [31]

    U. H. Danielsson, A. Guijosa and M. Kruczenski, Brane anti-brane systems at finite temperature and the entropy of black branes , JHEP 09 (2001) 011, [ hep-th/0106201]

  32. [32]

    Near-BPS-Saturated Rotating Electrically Charged Black Holes as String States

    M. Cvetic and D. Youm, Near BPS saturated rotating electrically charged black hol es as string states, Nucl. Phys. B 477 (1996) 449–464, [ hep-th/9605051]

  33. [33]

    Sigma model of near-extreme rotating black holes and their microstates

    M. Cvetic and A. A. Tseytlin, Sigma model of near extreme rotating black holes and their microstates, Nucl. Phys. B 537 (1999) 381–394, [ hep-th/9806141]

  34. [34]

    Decoupling Limit, Lens Spaces and Taub-NUT: D=4 Black Hole Microscopics from D=5 Black Holes

    M. Cvetic, H. Lu and C. N. Pope, Decoupling limit, lens spaces and Taub - NUT: D = 4 black hole microscopics from D = 5 black holes , Nucl. Phys. B 549 (1999) 194–214, [hep-th/9811107]

  35. [35]

    S. R. Das, The Effectiveness of D-branes in the description of near extre mal black holes , Phys. Rev. D 56 (1997) 3582–3590, [ hep-th/9703146]

  36. [36]

    J.-G. Zhou, H. J. W. Muller-Kirsten, J. Q. Liang and F. Zi mmerschied, M-branes, anti-M-branes and nonextremal black holes , Nucl. Phys. B 487 (1997) 155–173, [hep-th/9611146]

  37. [37]

    Calabi-Yau black holes and (0,4) sigma models

    R. Minasian, G. W. Moore and D. Tsimpis, Calabi-Yau black holes and (0,4) sigma models , Commun. Math. Phys. 209 (2000) 325–352, [ hep-th/9904217]

  38. [38]

    Microstates of a Neutral Black Hole in M Theory

    R. Emparan and G. T. Horowitz, Microstates of a Neutral Black Hole in M Theory , Phys. Rev. Lett. 97 (2006) 141601, [ hep-th/0607023]

  39. [39]

    BPS State Counting in N=8 Supersymmetric String Theory for Pure D-brane Configurations

    A. Chowdhury, R. S. Garavuso, S. Mondal and A. Sen, BPS State Counting in N=8 Supersymmetric String Theory for Pure D-brane Configurations , JHEP 10 (2014) 186, [1405.0412]

  40. [40]

    Do All BPS Black Hole Microstates Carry Zero Angular Momentum?

    A. Chowdhury, R. S. Garavuso, S. Mondal and A. Sen, Do All BPS Black Hole Microstates Carry Zero Angular Momentum? , JHEP 04 (2016) 082, [ 1511.06978]

  41. [41]

    Extremality Versus Supersymmetry in Stringy Black Holes

    T. Ortin, Extremality versus supersymmetry in stringy black holes , Phys. Lett. B 422 (1998) 93–100, [ hep-th/9612142]. – 13 –

  42. [42]

    E. G. Gimon, F. Larsen and J. Simon, Black holes in Supergravity: The Non-BPS branch , JHEP 01 (2008) 040, [ 0710.4967]

  43. [43]

    E. G. Gimon, F. Larsen and J. Simon, Constituent Model of Extremal non-BPS Black Holes , JHEP 07 (2009) 052, [ 0903.0719]

  44. [44]

    D. Shih, A. Strominger and X. Yin, Counting dyons in N=8 string theory , JHEP 06 (2006) 037, [ hep-th/0506151]

  45. [45]

    M Theory As A Matrix Model: A Conjecture

    T. Banks, W. Fischler, S. H. Shenker and L. Susskind, M theory as a matrix model: A Conjecture, Phys. Rev. D 55 (1997) 5112–5128, [ hep-th/9610043]

  46. [46]

    Bound States Of Strings And $p$-Branes

    E. Witten, Bound states of strings and p-branes , Nucl. Phys. B 460 (1996) 335–350, [hep-th/9510135]

  47. [47]

    Fayet and J

    P. Fayet and J. Iliopoulos, Spontaneously Broken Supergauge Symmetries and Goldstone Spinors, Phys. Lett. B 51 (1974) 461–464

  48. [48]

    Quantum Quivers and Hall/Hole Halos

    F. Denef, Quantum quivers and Hall / hole halos , JHEP 10 (2002) 023, [ hep-th/0206072]

  49. [49]

    I. Bena, M. Berkooz, J. de Boer, S. El-Showk and D. Van den Bleeken, Scaling BPS Solutions and pure-Higgs States , JHEP 11 (2012) 171, [ 1205.5023]

  50. [50]

    Arithmetic of Quantum Entropy Function

    A. Sen, Arithmetic of Quantum Entropy Function , JHEP 08 (2009) 068, [ 0903.1477]

  51. [51]

    Supersymmetric Index from Black Hole Entropy

    A. Dabholkar, J. Gomes, S. Murthy and A. Sen, Supersymmetric Index from Black Hole Entropy, JHEP 04 (2011) 034, [ 1009.3226]

  52. [52]

    How Do Black Holes Predict the Sign of the Fourier Coefficients of Siegel Modular Forms?

    A. Sen, How Do Black Holes Predict the Sign of the Fourier Coefficients o f Siegel Modular Forms?, Gen. Rel. Grav. 43 (2011) 2171–2183, [ 1008.4209]

  53. [53]

    On the positivity of black hole degeneracies in string theory

    K. Bringmann and S. Murthy, On the positivity of black hole degeneracies in string theor y, Commun. Num. Theor Phys. 07 (2013) 15–56, [ 1208.3476]. – 14 –