Unitary QFTs are determined up to unitary isomorphism by closed-manifold partition functions; every reflection-positive partition function comes from a unitary QFT, so spatial wormholes do not break Hilbert-space factorization once the full charged spectrum is included.
Positivity of the gravitational path integral implies the axionic weak gravity conjecture
9 Pith papers cite this work. Polarity classification is still indexing.
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Pith papers citing it
abstract
The gravitational path integral can compute inner products between different states of open and closed universes. To have a well-defined Hilbert space, these inner products should be positive semi-definite, which is not manifest in the low-energy effective theory. In this letter, we analyze the constraints that the positivity of inner products imposes on gravitational theories coupled to axions. If the axion has an exact shift symmetry, we show that, under mild assumptions, a combined positivity constraint on closed and open universes is violated when one includes certain wormholes. In low-energy effective theories where these wormholes are perturbatively stable, positivity requires that the wormholes have a non-perturbative instability that breaks the shift symmetry. This leads to a sharp version of the axion weak gravity conjecture, including precise numerical constants. We relate the bound to possible extensions of other swampland conjectures, arguing for an imaginary continuation of the distance conjecture. We comment on how the bound applies to axions in string theory and discuss phenomenological implications.
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background 3representative citing papers
Imaginary wormholes and the IDB imply that towers of BPS EFT instantons generate infinitely many superpotential terms that break non-invertible axion shift symmetries in N=1 axiverse models.
In F-theory GUTs, non-universal ALPs induced by hypercharge flux satisfy g_aγ/m_a well below the QCD axion prediction when gauge couplings unify near the string scale.
Hierarchical Bayesian analysis of GWTC-5 binary black hole spins finds no evidence for superradiant axions and excludes masses 1.7e-14 to 3.3e-12 eV at 95% CL.
The bound Λ_QG ≲ 2π √S f holds for C2 and C4 axions in Type IIB Calabi-Yau compactifications even near Kähler moduli space boundaries where co-scaling fails.
The paper verifies the bound fS/|n| ≤ (π/(2 κ_d)) sqrt((d-1)/(d-2)) for axion instantons and sharpens it to fS/|n| ≤ (1/κ_4) sqrt(7/2) for supersymmetric 4d instantons using three approaches in the string landscape.
Supergravity truncations admit real-metric wormhole solutions via imaginary scalar extensions whose holographic duals are pseudo-Hermitian and PT-symmetric, interpretable as entangled brane states.
The Type-IIB wormhole partition function in theta is the Fourier transform of charge-sector scalar coefficients W_ν[b], whose symmetry, positivity, and tail properties determine the partition function's analytic structure.
A review of string-inspired dynamical dark energy models claiming compatibility with DESI's hints of evolving dark energy under swampland constraints.
citing papers explorer
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Wormholes as red herrings: reflection positivity and the reconstruction of unitary quantum field theories
Unitary QFTs are determined up to unitary isomorphism by closed-manifold partition functions; every reflection-positive partition function comes from a unitary QFT, so spatial wormholes do not break Hilbert-space factorization once the full charged spectrum is included.
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Non-invertible symmetries in the axiverse, and the imaginary wormholes
Imaginary wormholes and the IDB imply that towers of BPS EFT instantons generate infinitely many superpotential terms that break non-invertible axion shift symmetries in N=1 axiverse models.
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Testing F-theory GUTs with the Axiverse
In F-theory GUTs, non-universal ALPs induced by hypercharge flux satisfy g_aγ/m_a well below the QCD axion prediction when gauge couplings unify near the string scale.
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No Evidence for Superradiant Axions in LIGO-Virgo-KAGRA GWTC-5 Binary Black Hole Spins
Hierarchical Bayesian analysis of GWTC-5 binary black hole spins finds no evidence for superradiant axions and excludes masses 1.7e-14 to 3.3e-12 eV at 95% CL.
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Quantum Gravity Cutoff from Axions: A Type IIB Landscape Study
The bound Λ_QG ≲ 2π √S f holds for C2 and C4 axions in Type IIB Calabi-Yau compactifications even near Kähler moduli space boundaries where co-scaling fails.
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Sharpening the Supersymmetric Axion Weak Gravity Conjecture
The paper verifies the bound fS/|n| ≤ (π/(2 κ_d)) sqrt((d-1)/(d-2)) for axion instantons and sharpens it to fS/|n| ≤ (1/κ_4) sqrt(7/2) for supersymmetric 4d instantons using three approaches in the string landscape.
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Supergravity flows, wormholes and their pseudo-Hermitian holographic duals
Supergravity truncations admit real-metric wormhole solutions via imaginary scalar extensions whose holographic duals are pseudo-Hermitian and PT-symmetric, interpretable as entangled brane states.
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Charge-Sector Construction of the Type-IIB Axion--Dilaton Wormhole Partition Function
The Type-IIB wormhole partition function in theta is the Fourier transform of charge-sector scalar coefficients W_ν[b], whose symmetry, positivity, and tail properties determine the partition function's analytic structure.
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Breaking Free from the Swampland of Impossible Universes through the DESI Portal
A review of string-inspired dynamical dark energy models claiming compatibility with DESI's hints of evolving dark energy under swampland constraints.