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arXiv · 2605.27453

Dirac-Line Criticality and Emergent Horizons in Weyl Lifshitz Transitions

Iftekher S. Chowdhury·Hom Nath Dhungana·Shah Haque·Hind Adawi·Eric Howard
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Abstract

Type-II Weyl fermions may emerge behind the event horizon of black holes. We employ the Painlev\'e-Gullstrand metric to study the surface of the Lifshitz transition at the horizon, equivalent to the interface separating the type-I and type-II Weyl states. We find several analogies between the black hole horizon and the transformation of type-I to type-II Weyl fermions through the Dirac line. We analyze the symmetry-protected topological order at the Lifshitz transition originating in semimetals. The emergence of Hawking radiation in Weyl semimetals is discussed. We show that the transition state from type-I to type-II Dirac fermions can be viewed as a black-hole horizon, which exhibits unique characteristics, including a Dirac-line Fermi surface with a nontrivial topological invariant and a critical chiral anomaly effect.

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Iftekher S. Chowdhury, Hom Nath Dhungana, Shah Haque, Hind Adawi, Eric Howard. 2026-05-25. Dirac-Line Criticality and Emergent Horizons in Weyl Lifshitz Transitions. https://arxiv.org/abs/2605.27453

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