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arXiv · 2509.20437

The degrees of freedom of multiway junctions in three dimensional gravity

Avik Chakraborty·Tanay Kibe·Martín Molina·Ayan Mukhopadhyay·Giuseppe Policastro
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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-Amp\`{e}re like terms which couple the strings. For $n\geq 3$, these $n-1$ degrees of freedom survive the tensionless limit implying that matter-like behavior can arise out of \textit{pure} gravity. We interpret these stringy degrees of freedom of gravitational junctions holographically in terms of wavepackets which collectively undergo perfect reflection at the multi-interface in the dual conformal field theory.

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Avik Chakraborty, Tanay Kibe, Martín Molina, Ayan Mukhopadhyay, Giuseppe Policastro. 2025-09-24. The degrees of freedom of multiway junctions in three dimensional gravity. https://doi.org/10.1103/yy6l-1b4b

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