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  • Open Access

Degrees of freedom of multiway junctions in three dimensional gravity

Avik Chakraborty*

Tanay Kibe†

Martín Molina‡

Ayan Mukhopadhyay§

Giuseppe Policastro∥

  • Departamento de Ciencias Físicas, Facultad de Ciencias Exactas, Universidad Andres Bello, Sazié 2212, Piso 7, Santiago, Chile

  • National Institute for Theoretical and Computational Sciences, School of Physics and Mandelstam Institute for Theoretical Physics, University of the Witwatersrand, Wits, 2050, South Africa

  • *Contact author: avik.phys88@gmail.com
  • †Contact author: tanay.kibe@wits.ac.za
  • ‡Contact author: martinmolinaramos95@gmail.com
  • §Contact author: ayan.mukhopadhyay@pucv.cl
  • ∥Contact author: giuseppe.policastro@phys.ens.fr
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Phys. Rev. D 113, 106027 – Published 22 May, 2026

DOI: https://doi.org/10.1103/yy6l-1b4b

Abstract

We demonstrate that n-way junctions in three-dimensional gravity correspond to coupled n−1 strings each satisfying the Nambu-Goto equation in the smoothened background and with sources consisting of Monge-Ampère like terms which couple the strings. For n≥3, these n−1 degrees of freedom survive the tensionless limit implying that matterlike behavior can arise out of pure gravity. We interpret these stringy degrees of freedom of gravitational junctions holographically in terms of wave packets, which collectively undergo perfect reflection at the multi-interface in the dual conformal field theory.

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Phys. Rev. D 113, 106027– Published 22 May, 2026
  • Received 22 October 2025
  • Revised 19 February 2026
  • Accepted 28 April 2026
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