A predictive mirror twin Higgs with small Z2 breaking


The twin Higgs mechanism is a solution to the little hierarchy problem in which the top partner is neutral under the Standard Model (SM) gauge group. The simplest mirror twin Higgs (MTH) model — where a Z2 symmetry copies each SM particle — has too many relativistic degrees of freedom to be consistent with cosmological observations. We demonstrate that MTH models can have an observationally viable cosmology if the twin mass spectrum leads to twin neutrino decoupling before the SM and twin QCD phase transitions. Our solution requires the twin photon to have a mass of 20 MeV and kinetically mix with the SM photon to mediate entropy transfer from the twin sector to the SM. This twin photon can be robustly discovered or excluded by future experiments. Additionally, the residual twin degrees of freedom present in the early Universe in this scenario would be detectable by future observations of the cosmic microwave background.

A preprint version of the article is available at ArXiv.


  1. [1]

    H. Murayama, Supersymmetry phenomenology, in the proceedings of the Proceedings, Summer School in Particle Physics, July 21–July 9, Trieste, Italy (1999), hep-ph/0002232 [INSPIRE].

  2. [2]

    L. Maiani, All you need to know about the Higgs boson, Conf.Proc.C 7909031 (1979) 1.

    Google Scholar 

  3. [3]

    M.J.G. Veltman, The infrared-ultraviolet connection, Acta Phys. Polon.B 12 (1981) 437 [INSPIRE].

    Google Scholar 

  4. [4]

    E. Witten, Dynamical breaking of supersymmetry, Nucl. Phys.B 188 (1981) 513 [INSPIRE].

    ADS  MATH  Article  Google Scholar 

  5. [5]

    R.K. Kaul, Gauge hierarchy in a supersymmetric model, Phys. Lett.B 109 (1982) 19.

    ADS  Article  Google Scholar 

  6. [6]

    D.B. Kaplan and H. Georgi, SU(2) × U(1) breaking by vacuum misalignment, Phys. Lett.B 136 (1984) 183.

    ADS  Article  Google Scholar 

  7. [7]

    D.B. Kaplan, H. Georgi and S. Dimopoulos, Composite Higgs scalars, Phys. Lett.B 136 (1984) 187.

    ADS  Article  Google Scholar 

  8. [8]

    ATLAS collaboration, Search for top squarks decaying to tau sleptons in pp collisions at \( \sqrt{s} \) = 13 TeV with the ATLAS detector, Phys. Rev.D 98 (2018) 032008 [arXiv:1803.10178] [INSPIRE].

  9. [9]

    CMS collaboration, Search for natural and split supersymmetry in proton-proton collisions at \( \sqrt{s} \) = 13 TeV in final states with jets and missing transverse momentum, JHEP 05 (2018) 025 [arXiv:1802.02110] [INSPIRE].

  10. [10]

    ATLAS collaboration, Search for single production of a vector-like quark via a heavy gluon in the 4b final state with the ATLAS detector in pp collisions at \( \sqrt{s} \) = 8 TeV, Phys. Lett. B 758 (2016) 249 [arXiv:1602.06034] [INSPIRE].

  11. [11]

    CMS collaboration, Search for vector-like T and B quark pairs in final states with leptons at \( \sqrt{s} \) = 13 TeV, JHEP08 (2018) 177 [arXiv:1805.04758] [INSPIRE].

  12. [12]

    Z. Chacko, H.-S. Goh and R. Harnik, The twin Higgs: natural electroweak breaking from mirror symmetry, Phys. Rev. Lett.96 (2006) 231802 [hep-ph/0506256] [INSPIRE].

  13. [13]

    A. Falkowski, S. Pokorski and M. Schmaltz, Twin SUSY, Phys. Rev.D 74 (2006) 035003 [hep-ph/0604066] [INSPIRE].

  14. [14]

    S. Chang, L.J. Hall and N. Weiner, A supersymmetric twin Higgs, Phys. Rev.D 75 (2007) 035009 [hep-ph/0604076] [INSPIRE].

  15. [15]

    N. Craig and K. Howe, Doubling down on naturalness with a supersymmetric twin Higgs, JHEP03 (2014) 140 [arXiv:1312.1341] [INSPIRE].

    ADS  Article  Google Scholar 

  16. [16]

    A. Katz, A. Mariotti, S. Pokorski, D. Redigolo and R. Ziegler, SUSY meets her twin, JHEP01 (2017) 142 [arXiv:1611.08615] [INSPIRE].

    ADS  MATH  Article  Google Scholar 

  17. [17]

    M. Badziak and K. Harigaya, Supersymmetric D-term twin Higgs, JHEP06 (2017) 065 [arXiv:1703.02122] [INSPIRE].

    ADS  Article  Google Scholar 

  18. [18]

    M. Badziak and K. Harigaya, Minimal non-Abelian supersymmetric twin Higgs, JHEP10 (2017) 109 [arXiv:1707.09071] [INSPIRE].

    ADS  Article  Google Scholar 

  19. [19]

    M. Badziak and K. Harigaya, Asymptotically free natural supersymmetric twin Higgs model, Phys. Rev. Lett.120 (2018) 211803 [arXiv:1711.11040] [INSPIRE].

    ADS  Article  Google Scholar 

  20. [20]

    P. Batra and Z. Chacko, A composite twin Higgs model, Phys. Rev.D 79 (2009) 095012 [arXiv:0811.0394] [INSPIRE].

    ADS  Google Scholar 

  21. [21]

    M. Geller and O. Telem, Holographic twin Higgs model, Phys. Rev. Lett.114 (2015) 191801 [arXiv:1411.2974] [INSPIRE].

    ADS  Article  Google Scholar 

  22. [22]

    R. Barbieri, D. Greco, R. Rattazzi and A. Wulzer, The composite twin Higgs scenario, JHEP08 (2015) 161 [arXiv:1501.07803] [INSPIRE].

    MathSciNet  MATH  Article  Google Scholar 

  23. [23]

    M. Low, A. Tesi and L.-T. Wang, Twin Higgs mechanism and a composite Higgs boson, Phys. Rev.D 91 (2015) 095012 [arXiv:1501.07890] [INSPIRE].

    ADS  Google Scholar 

  24. [24]

    H.-C. Cheng, S. Jung, E. Salvioni and Y. Tsai, Exotic quarks in twin Higgs models, JHEP03 (2016) 074 [arXiv:1512.02647] [INSPIRE].

    ADS  Article  Google Scholar 

  25. [25]

    C. Csáki, M. Geller, O. Telem and A. Weiler, The flavor of the composite twin Higgs, JHEP09 (2016) 146 [arXiv:1512.03427] [INSPIRE].

    ADS  Article  Google Scholar 

  26. [26]

    H.-C. Cheng, E. Salvioni and Y. Tsai, Exotic electroweak signals in the twin Higgs model, Phys. Rev.D 95 (2017) 115035 [arXiv:1612.03176] [INSPIRE].

    ADS  Google Scholar 

  27. [27]

    R. Contino et al., Precision tests and fine tuning in twin Higgs models, Phys. Rev.D 96 (2017) 095036 [arXiv:1702.00797] [INSPIRE].

    ADS  Google Scholar 

  28. [28]

    P.F. de Salas and S. Pastor, Relic neutrino decoupling with flavour oscillations revisited, JCAP07 (2016) 051 [arXiv:1606.06986] [INSPIRE].

    Article  Google Scholar 

  29. [29]

    G. Mangano, G. Miele, S. Pastor and M. Peloso, A precision calculation of the effective number of cosmological neutrinos, Phys. Lett.B 534 (2002) 8 [astro-ph/0111408] [INSPIRE].

  30. [30]

    Z. Chacko, N. Craig, P.J. Fox and R. Harnik, Cosmology in mirror twin Higgs and neutrino masses, JHEP07 (2017) 023 [arXiv:1611.07975] [INSPIRE].

    ADS  Article  Google Scholar 

  31. [31]

    R.H. Cyburt, B.D. Fields, K.A. Olive and T.-H. Yeh, Big Bang nucleosynthesis: 2015, Rev. Mod. Phys.88 (2016) 015004 [arXiv:1505.01076] [INSPIRE].

    ADS  Article  Google Scholar 

  32. [32]

    Planck collaboration, Planck 2018 results. VI. Cosmological parameters, arXiv:1807.06209 [INSPIRE].

  33. [33]

    N. Craig, A. Katz, M. Strassler and R. Sundrum, Naturalness in the dark at the LHC, JHEP07 (2015) 105 [arXiv:1501.05310] [INSPIRE].

    ADS  Article  Google Scholar 

  34. [34]

    N. Craig and A. Katz, The fraternal WIMP miracle, JCAP10 (2015) 054 [arXiv:1505.07113] [INSPIRE].

    ADS  Article  Google Scholar 

  35. [35]

    R. Barbieri, L.J. Hall and K. Harigaya, Minimal mirror twin Higgs, JHEP11 (2016) 172 [arXiv:1609.05589] [INSPIRE].

    ADS  Article  Google Scholar 

  36. [36]

    C. Csáki, E. Kuflik and S. Lombardo, Viable twin cosmology from neutrino mixing, Phys. Rev.D 96 (2017) 055013 [arXiv:1703.06884] [INSPIRE].

    ADS  Google Scholar 

  37. [37]

    B. Batell and C.B. Verhaaren, Breaking mirror twin hypercharge, JHEP12 (2019) 010 [arXiv:1904.10468] [INSPIRE].

    ADS  Article  Google Scholar 

  38. [38]

    D. Liu and N. Weiner, A portalino to the twin sector, arXiv:1905.00861 [INSPIRE].

  39. [39]

    Y. Hochberg, E. Kuflik and H. Murayama, Twin Higgs model with strongly interacting massive particle dark matter, Phys. Rev.D 99 (2019) 015005 [arXiv:1805.09345] [INSPIRE].

    ADS  Google Scholar 

  40. [40]

    H.-C. Cheng, L. Li and R. Zheng, Coscattering/coannihilation dark matter in a fraternal twin Higgs model, JHEP09 (2018) 098 [arXiv:1805.12139] [INSPIRE].

    ADS  Article  Google Scholar 

  41. [41]

    N. Craig, S. Koren and T. Trott, Cosmological signals of a mirror twin Higgs, JHEP05 (2017) 038 [arXiv:1611.07977] [INSPIRE].

    ADS  MATH  Article  Google Scholar 

  42. [42]

    N. Craig, S. Knapen, P. Longhi and M. Strassler, The vector-like twin Higgs, JHEP07 (2016) 002 [arXiv:1601.07181] [INSPIRE].

    ADS  MathSciNet  MATH  Article  Google Scholar 

  43. [43]

    S. Koren and R. McGehee, Freezing-in twin dark matter, Phys. Rev.D 101 (2020) 055024 [arXiv:1908.03559] [INSPIRE].

    ADS  Google Scholar 

  44. [44]

    Z. Chacko, D. Curtin, M. Geller and Y. Tsai, Cosmological signatures of a mirror twin Higgs, JHEP09 (2018) 163 [arXiv:1803.03263] [INSPIRE].

    ADS  Article  Google Scholar 

  45. [45]

    R. Barbieri, L.J. Hall and K. Harigaya, Effective theory of flavor for minimal mirror twin Higgs, JHEP10 (2017) 015 [arXiv:1706.05548] [INSPIRE].

    ADS  Article  Google Scholar 

  46. [46]

    C.D. Froggatt and H.B. Nielsen, Hierarchy of quark masses, Cabibbo angles and CP-violation, Nucl. Phys.B 147 (1979) 277 [INSPIRE].

    ADS  Article  Google Scholar 

  47. [47]

    T. Yanagida, Horizontal gauge symmetry and masses of neutrinos, Conf. Proc.C 7902131 (1979) 95 [INSPIRE].

    Google Scholar 

  48. [48]

    M. Gell-Mann, P. Ramond and R. Slansky, Complex spinors and unified theories, Conf. Proc.C 790927 (1979) 315 [arXiv:1306.4669] [INSPIRE].

    Google Scholar 

  49. [49]

    P. Minkowski, μ → eγ at a rate of one out of 109muon decays?, Phys. Lett.B 67 (1977) 421.

  50. [50]

    R.N. Mohapatra and G. Senjanović, Neutrino mass and spontaneous parity nonconservation, Phys. Rev. Lett.44 (1980) 912 [INSPIRE].

    ADS  MATH  Article  Google Scholar 

  51. [51]

    M. Fukugita and T. Yanagida, Baryogenesis without grand unification, Phys. Lett.B 174 (1986) 45 [INSPIRE].

    ADS  Article  Google Scholar 

  52. [52]

    G.F. Giudice et al., Towards a complete theory of thermal leptogenesis in the SM and MSSM, Nucl. Phys.B 685 (2004) 89 [hep-ph/0310123] [INSPIRE].

  53. [53]

    W. Buchmüller, P. Di Bari and M. Plümacher, Leptogenesis for pedestrians, Annals Phys.315 (2005) 305 [hep-ph/0401240] [INSPIRE].

  54. [54]

    ATLAS, CMS collaboration, Measurements of the Higgs boson production and decay rates and constraints on its couplings from a combined ATLAS and CMS analysis of the LHC pp collision data at \( \sqrt{s} \) = 7 and 8 TeV, JHEP 08 (2016) 045 [arXiv:1606.02266] [INSPIRE].

  55. [55]

    J.H. Chang, R. Essig and S.D. McDermott, Revisiting supernova 1987A constraints on dark photons, JHEP01 (2017) 107 [arXiv:1611.03864] [INSPIRE].

    ADS  MATH  Google Scholar 

  56. [56]

    W. DeRocco et al., Observable signatures of dark photons from supernovae, JHEP02 (2019) 171 [arXiv:1901.08596] [INSPIRE].

    ADS  Article  Google Scholar 

  57. [57]

    A. Sung, H. Tu and M.-R. Wu, New constraint from supernova explosions on light particles beyond the Standard Model, Phys. Rev.D 99 (2019) 121305 [arXiv:1903.07923] [INSPIRE].

    ADS  Google Scholar 

  58. [58]

    J. Alexander et al., Dark sectors 2016 workshop: community report, arXiv:1608.08632 [FERMILAB-CONF-16-421].

  59. [59]

    R.H. Parker et al., Measurement of the fine-structure constant as a test of the standard model, Science360 (2018) 191 [arXiv:1812.04130] [INSPIRE].

    ADS  MathSciNet  MATH  Article  Google Scholar 

  60. [60]

    A. Berlin et al., Dark matter, millicharges, axion and scalar particles, gauge bosons and other new physics with LDMX, Phys. Rev.D 99 (2019) 075001 [arXiv:1807.01730] [INSPIRE].

    ADS  Google Scholar 

  61. [61]

    B. Echenard, R. Essig and Y.-M. Zhong, Projections for dark photon searches at Mu3e, JHEP01 (2015) 113 [arXiv:1411.1770] [INSPIRE].

    ADS  Article  Google Scholar 

  62. [62]

    A. Berlin, S. Gori, P. Schuster and N. Toro, Dark sectors at the Fermilab SeaQuest experiment, Phys. Rev.D 98 (2018) 035011 [arXiv:1804.00661] [INSPIRE].

    ADS  Google Scholar 

  63. [63]

    HPS collaboration, The heavy photon search experiment at Jefferson laboratory, J. Phys. Conf. Ser.556 (2014) 012064 [arXiv:1505.02025] [INSPIRE].

  64. [64]

    S. Alekhin et al., A facility to search for hidden particles at the CERN SPS: the SHiP physics case, Rept. Prog. Phys.79 (2016) 124201 [arXiv:1504.04855] [INSPIRE].

    ADS  Article  Google Scholar 

  65. [65]

    FASER collaboration, FASER’s physics reach for long-lived particles, Phys. Rev.D 99 (2019) 095011 [arXiv:1811.12522] [INSPIRE].

  66. [66]

    NA62 collaboration, Search for hidden sector particles at NA62, PoS(EPS-HEP2017)301.

  67. [67]

    Particle Data Group collaboration, Review of particle physics, Phys. Rev.D 98 (2018) 030001 [INSPIRE].

  68. [68]

    P. Bambade et al., The International Linear Collider: a global project, arXiv:1903.01629 [INSPIRE].

  69. [69]

    B. Henning, X. Lu, T. Melia and H. Murayama, 2, 84, 30, 993, 560, 15456, 11962, 261485, . . .: higher dimension operators in the SM EFT, JHEP08 (2017) 016 [Erratum ibid.09 (2019) 019] [arXiv:1512.03433] [INSPIRE].

  70. [70]

    V.A. Novikov et al., Charmonium and gluons: basic experimental facts and theoretical introduction, Phys. Rept.41 (1978) 1 [INSPIRE].

    ADS  Article  Google Scholar 

  71. [71]

    G. Mangano et al., Effects of non-standard neutrino-electron interactions on relic neutrino decoupling, Nucl. Phys.B 756 (2006) 100 [hep-ph/0607267] [INSPIRE].

  72. [72]

    E. Aver, K.A. Olive and E.D. Skillman, The effects of He I λ10830 on helium abundance determinations, JCAP07 (2015) 011 [arXiv:1503.08146] [INSPIRE].

    ADS  Article  Google Scholar 

  73. [73]

    R. Galvez and R.J. Scherrer, Cosmology with independently varying neutrino temperature and number, Phys. Rev.D 95 (2017) 063507 [arXiv:1609.06351] [INSPIRE].

    ADS  Google Scholar 

  74. [74]

    A. Arbey, AlterBBN: a program for calculating the BBN abundances of the elements in alternative cosmologies, Comput. Phys. Commun.183 (2012) 1822 [arXiv:1106.1363] [INSPIRE].

    ADS  Article  Google Scholar 

  75. [75]

    A. Arbey, J. Auffinger, K.P. Hickerson and E.S. Jenssen, AlterBBN v2: a public code for calculating Big-Bang nucleosynthesis constraints in alternative cosmologies, Comput. Phys. Commun.248 (2020) 106982 [arXiv:1806.11095] [INSPIRE].

    Article  Google Scholar 

  76. [76]

    SPT-3G collaboration, SPT-3G: a next-generation cosmic microwave background polarization experiment on the South Pole Telescope, Proc. SPIE Int. Soc. Opt. Eng.9153 (2014) 91531P [arXiv:1407.2973] [INSPIRE].

  77. [77]

    ACTPol collaboration, The Atacama Cosmology Telescope: two-season ACTPol spectra and parameters, JCAP06 (2017) 031 [arXiv:1610.02360] [INSPIRE].

  78. [78]

    POLARBEAR collaboration, The POLARBEAR-2 and the Simons Array Experiment, J. Low. Temp. Phys.184 (2016) 805 [arXiv:1512.07299] [INSPIRE].

  79. [79]

    BICEP3 collaboration, BICEP3 performance overview and planned Keck Array upgrade, Proc. SPIE Int. Soc. Opt. Eng.9914 (2016) 99140S [arXiv:1607.04668] [INSPIRE].

  80. [80]

    CMB-S4 collaboration, CMB-S4 science book, first edition, arXiv:1610.02743 [INSPIRE].

  81. [81]

    A. Denner, S. Heinemeyer, I. Puljak, D. Rebuzzi and M. Spira, Standard model Higgs-boson branching ratios with uncertainties, Eur. Phys. J.C 71 (2011) 1753 [arXiv:1107.5909] [INSPIRE].

    ADS  Article  Google Scholar 

  82. [82]

    ATLAS collaboration, Combined measurements of Higgs boson production and decay in the H → Z Z 4ℓ and H → γγ channels using \( \sqrt{s} \) = 13 TeV pp collision data collected with the ATLAS experiment, ATLAS-CONF-2019-005 (2019).

Download references

Open Access

This article is distributed under the terms of the Creative Commons Attribution License (CC-BY 4.0), which permits any use, distribution and reproduction in any medium, provided the original author(s) and source are credited

Author information



Corresponding author

Correspondence to Robert McGehee.

Additional information

Publisher’s Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

ArXiv ePrint: 1905.08798

Hamamatsu professor. (Hitoshi Murayama)

Rights and permissions

This article is published under an open access license. Please check the 'Copyright Information' section for details of this license and what re-use is permitted. If your intended use exceeds what is permitted by the license or if you are unable to locate the licence and re-use information, please contact the Rights and Permissions team.

About this article

Verify currency and authenticity via CrossMark

Cite this article

Harigaya, K., McGehee, R., Murayama, H. et al. A predictive mirror twin Higgs with small Z2 breaking. J. High Energ. Phys. 2020, 155 (2020). https://doi.org/10.1007/JHEP05(2020)155

Download citation


  • Beyond Standard Model
  • Higgs Physics