Searcharxiv⌕ Search
Home/Archive/arXiv

arXiv · 2609.28637

Breaking de Sitter Symmetry with Cosmic Topology: Cosmological Role of Infrared Vacuum Freedom

Anna Negro·Kurt Hinterbichler·Glenn D. Starkman·Yashar Akrami·Stefano Anselmi·Javier Carrón Duque·Mikel Martin Barandiaran·Andrius Tamosiunas
View original source ↗Read source document ↗Export metadata ↓

Abstract

When spatial sections of spacetime are topologically nontrivial, the symmetry arguments usually used to choose the Bunch-Davies vacuum are no longer guaranteed to apply. We study this problem for a scalar field on de Sitter spacetime with toroidal spatial sections. The Hadamard conditions, which ensure the same short-distance structure as in flat space, are local and naturally insensitive to the compactification. By contrast, we find that the infrared sector is affected by the toroidal identifications that break global de Sitter invariance, thereby removing the usual argument for discarding zero-mode contributions. We treat the remaining zero-mode freedom as an effective topology-induced source and analyze its effects on an inflationary de Sitter expansion within a semiclassical setting. We show that, for a massless scalar, the zero-mode sector can contain a contribution to the stress-energy tensor with equation of state $P=-ρ$, behaving as a cosmological constant. Thus, the source driving an early-Universe de Sitter phase need not be determined solely by local terms in the action, but can also depend on the infrared structure of the quantum state. Nontrivial topology, as a concrete realization of de Sitter symmetry violation, turns the otherwise-unfixed infrared freedom in vacuum selection to a contribution directly relevant to the semiclassical expansion. This contribution could potentially be applicable to the current accelerated expansion of the Universe.

Explore related subjects

hep-th

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Anna Negro, Kurt Hinterbichler, Glenn D. Starkman, Yashar Akrami, Stefano Anselmi, Javier Carrón Duque, Mikel Martin Barandiaran, Andrius Tamosiunas. 2026-09-23. Breaking de Sitter Symmetry with Cosmic Topology: Cosmological Role of Infrared Vacuum Freedom. https://arxiv.org/abs/2609.28637

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

arXiv2026

Mirror Symmetry, the Schwarzian Derivative, and the Modularity of Seiberg--Witten Theory

We study the Schwarzian derivative of the Seiberg--Witten period ratio in the rigid limit of the two-parameter mirror family associated with a degree-$12$ Calabi--Yau hypersurface in $\mathbb{P}^4_{1,1,2,2,6}$. The leading tangential Yukawa coefficient is proportional to the holomorphic cubic tensor of rigid special Kähler geometry. Using the mixed normal components and a prescribed constant-coefficient connection rule, we reconstruct the Schwarzian quadratic differential, whose coefficient in the effective coupling $τ$ is $π^2θ_2(τ/2)^8/8$. With the weak-coupling frame, dynamical scale, and perturbative normalization fixed, we prove that the holomorphic germ of this coefficient determines the prepotential up to an additive constant within a convergent local class, and vanishes identically if and only if all instanton corrections vanish. We then use the genus-zero mirror correspondence in the chosen chamber to relate the first two Schwarzian Fourier coefficients to compact Gromov--Witten invariants. The Picard--Fuchs system and full Yukawa tensor give the generating functions at base degrees one and two and their asymptotics as the fiber degree tends to infinity. Locally uniform period estimates fix the rigid-limit normalization and justify extraction of the gauge-instanton coefficients. This yields an explicit asymptotic relation between the compact invariants and the normalized second Schwarzian coefficient. The extension to higher base degree remains conditional.

hep-th↗
arXiv2026

Generalised anomalies, QCD$_4$, and holography

During the last decade, the notion of an 't Hooft anomaly has been generalised to the case of discrete symmetries. An interesting instance, discussed by Tanizaki, is the mixed anomaly between the discrete axial symmetry and the flavour and baryonic symmetries in massless QCD$_4$. The goal of this note is to provide a derivation of this anomaly from a top-down holographic dual of QCD$_4$. It is found that the topological couplings in the bulk supergravity dual of the D4-D8 system encode Tanizaki's anomaly, once fluctuations around the bulk gauge fields are turned on. A technical challenge for this computation is the difficulty in maintaining gauge invariance of supergravity theories in the presence of D-branes. To overcome this issue, a compact formulation of the flux sector of (massive) type IIA supergravity in the presence of D8 branes is presented. A crucial ingredient in the analysis is the need for smearing the D8 branes, in order to impose $τ$-shift invariance on the fluctuation ansatz.

hep-th↗
arXiv2026

Neutrinos, B-L Symmetry and the Dark Dimension

We consider realizations of a gauged B-L symmetry in the context of the Dark Dimension scenario, where the SM lives on a codimension one brane in 5d spacetime. The B-L can naturally be a bulk gauge symmetery leading to a global symmetry on the SM brane, and have its gauge anomaly canceled by charged bulk modes. This naturally leads to the existence of 3 right-handed neutrinos propagating in the dark dimension. Allowing for spontaneous breaking of B-L in the bulk results in a massive gauge field with a very weak coupling $g_{B-L}\sim 10^{-10}$; for instance, B-L breaking at the weak scale gives $m_{B-L}\sim 100$ GeV, which is allowed by current bounds, as is a wide range of other values of the B-L breaking scale. The bulk sterile neutrinos are expected to have a mass of the order of the B-L breaking scale. Once the full Kaluza-Klein tower of bulk neutrinos is taken into account, the active neutrino masses turn out to be insensitive to the sterile neutrino mass, and reproduce the original Dark Dimension estimate $m_ν\sim y^2\langle H\rangle^2/M_5$, which leads to the observed neutrino mass scale for Yukawa couplings $y\sim 10^{-3}$.

hep-th↗