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// overview

I study the deep mathematical structure of spacetime — from the geometry of its boundaries to the quantum fluctuations at its smallest scales.

My research spans conformal geometry, general relativity, quantum gravity, and cosmology. On the geometric side, I develop a systematic theory of conformal hypersurface invariants — canonical extrinsic curvatures that govern when conformally compact manifolds are related to Poincaré-Einstein metrics — with applications to Willmore energies, Q-curvatures, and holographic boundary problems.

On the quantum gravity and cosmology side, I have studied curvature fluctuations in discrete models of quantum spacetime and explored holographic dark energy scenarios, including constraints on exotic cosmological futures such as the "long freeze." These threads are unified by a broader interest in understanding the deep mathematical structure of spacetime, from its microscopic quantum origins to its large-scale cosmological evolution.

// research interests

Conformal Geometry Poincaré-Einstein Manifolds Willmore Invariants Carrollian Geometry Null Hypersurfaces Black Hole Thermodynamics Quantum Gravity Holographic Dark Energy Cosmology Flat-Space Holography BMS Symmetry General Relativity

// selected publications

2025 Conformal Geometry
Conformal hypersurface invariants and Bach-type Boundary Problems
Samuel Blitz & A. Rod Gover

We establish the existence of a new symmetric trace-free tensor conformal invariant of hypersurface embeddings in even-dimensional conformal manifolds, completing the family of conformal fundamental forms. The object has important links to global problems and to the Poincaré–Einstein boundary value problem.

arXiv:2511.02072 · Submitted 2025
arXiv →
2025 Poincaré-Einstein Holography
The Dirichlet-to-Neumann Map for Poincaré–Einstein Fillings
Samuel Blitz, A. Rod Gover, Jarosław Kopiński & Andrew Waldron

We study the nonlinear Dirichlet-to-Neumann map for the Poincaré–Einstein filling problem. For even-dimensional manifolds, the range of this non-local map is described in terms of a rank-two tensor along the boundary, proportional to the variation of renormalized volume.

Revista Matemática Iberoamericana · arXiv:2307.08470
arXiv →
2026 Carrollian Geometry
Potential Carroll Structures and Special Carrollian Manifolds
Samuel Blitz

We introduce a new geometric structure — potential Carroll structures — on three-manifolds equipped with a preferred direction, and determine the conditions relating them to special Carrollian manifolds (SCMs), with implications for null hypersurface geometry and holography.

arXiv:2601.20068 · January 2026
arXiv →
2024 Quantum Gravity
Curvature Fluctuations in a Baby Quantum Gravity Model
Samuel Blitz et al.

Understanding the microscopic behavior of spacetime is critical for developing a theory of quantum gravity. We analyze curvature fluctuations in a discrete, baby model of quantum spacetime, probing how classical geometry emerges from quantum structure.

arXiv:2405.18397 · 2024
arXiv →
2024 Carrollian / GR
Horizons that Gyre and Gimble: A Differential Characterization of Null Hypersurfaces
Samuel Blitz & David McNutt

We study the geometric invariant theory of null hypersurfaces, developing a Carrollian hypersurface calculus for intrinsic and extrinsic differential invariants. Motivated by black hole thermodynamics, we argue that a connection with torsion is the most natural object to study Carrollian manifolds.

arXiv:2310.08141 · 2024
arXiv →
2024 Submanifold Geometry
Holography of Higher Codimension Submanifolds: Riemannian and Conformal
Samuel Blitz & Josef Šilhan

We generalize holographic methods to higher-codimension submanifolds, extracting higher-order local invariants of both Riemannian and conformal embeddings. New behavior arises in the higher-codimension case, giving rise to invariants that obstruct the order-by-order construction of unit defining maps.

arXiv:2405.07692 · 2024
arXiv →
2023 Conformal Geometry Willmore
Generalized Willmore Energies, Q-Curvatures, Extrinsic Paneitz Operators, and Extrinsic Laplacian Powers
Samuel Blitz, A. Rod Gover & Andrew Waldron

We explicitly compute the extrinsic Paneitz operator and apply it to obtain an extrinsically-coupled Q-curvature for embedded four-manifolds, the anomaly in renormalized volumes for conformally compact five-manifolds, and generalized Willmore energies in all even dimensions.

Communications in Contemporary Mathematics · arXiv:2111.00179
arXiv →
2022 Conformal Geometry
Conformal Fundamental Forms and the Asymptotically Poincaré-Einstein Condition
Samuel Blitz, A. Rod Gover & Andrew Waldron

We construct a sequence of conformally invariant higher fundamental forms and show that their vanishing is a necessary and sufficient condition for a conformally compact metric to be conformally related to an asymptotically Poincaré-Einstein metric.

Indiana University Mathematics Journal · arXiv:2107.10381
arXiv →