arXiv subjects

Stefania De Matteo

Publications and source records attributed to Stefania De Matteo.

3 recordsLinked to original sources

arXiv2026

Spectral Suppression of Asymptotic States in Supersymmetric QFT on de Sitter Backgrounds

We investigate the fate of asymptotic particle states in supersymmetric quantum field theories on de Sitter backgrounds, distinguishing algebraic field content from localized LSZ-like excitations. We study how long-wavelength gravitational fluctuations may suppress pole residues and redistribute spectral weight from isolated contributions toward continuum sectors. The analysis is formulated within a Kallen-Lehmann spectral framework and is intended as a structural infrared mechanism rather than a non-perturbative proof of de Sitter quantum gravity. The paper develops three connected levels. First, we analyze residue suppression in a quasi-de Sitter setting and its possible transmission through Yukawa and gravitational interactions. Second, we formulate the spectral decomposition as a map between the full field-theoretic spectrum and the observable particle sector. Third, we examine a conditional cosmological realization of redistributed spectral weight, including possible effects on expansion, structure growth, and lensing. This cosmological layer is a downstream phenomenological test and is not used as evidence that pole loss has occurred. In the current MCMC analysis we find S8 approximately 0.803 and, when the smooth fraction is varied, fS8 = 0.0025 +/- 0.0017, consistent with the benchmark value 0.00262. These results test the internal consistency of the proposed realization but do not establish the dark-sector assignment or the underlying infrared mechanism.

hep-th↗

arXiv2026

A structural criterion for asymptotic states in Supersymmetry

The occurrence of a field in the formal structure of a quantum field theory does not by itself establish the existence of a corresponding asymptotic particle. We develop a structural criterion separating three logically distinct questions: which field structures are admissible, which survive the dynamics as localized spectral excitations, and which are realized as operational particle states. The revised exterior-polynomial classification of gravitino mass bilinears provides the operator-level prototype for this distinction. Transposing this layered logic from operators to states, we formulate particlehood as the endpoint of an ordered filtration: spacetime geometry and the quantum state determine the spectral environment; the effective algebra fixes the physically realized symmetries and admissible channels; dynamics modifies the dressed two-point function; and spectral analysis determines whether an isolated atomic contribution survives. The localization criterion is thereby given measure-theoretic content: a stable asymptotic particle state requires an isolated spectral atom with non-zero weight. The framework also clarifies two limits of the original formulation. The apparent fermion-scalar asymmetry is channel-specific rather than universal, and no asymmetric realization of particlehood within an exact supersymmetric multiplet is possible while the supercharges act on the physical Hilbert space and annihilate the vacuum. Any split therefore requires supersymmetry breaking, altered background realization, or kinematic and dynamical differences among the relevant channels. The paper establishes necessary structural conditions only; their quantitative realization is deferred to a companion work.

hep-th↗

arXiv2026

Structural Origin of the Gravitino Mass Term: Geometric and Supergravity Perspectives

We identify a minimal superspace projector that uniquely selects the Rarita Schwinger mass bilinear in four-dimensional N=1 supergravity. Working in a reduced superspace with a single fermionic direction, we show that Berezin projection of a canonical even supergeometric form isolates the unique Lorentz-invariant fermionic bilinear compatible with local supersymmetry. The construction is predynamical: it fixes the algebraic structure of the gravitino mass term independently of supersymmetry breaking mechanisms, background geometry, or matter couplings. We show that this projector embeds consistently into curved superspace, extends to N>1 theories, and clarifies the universality of the gravitino mass structure in supergravity.

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