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arxiv: 2605.13777 · v1 · submitted 2026-05-13 · ✦ hep-th · gr-qc

Recognition: unknown

Before the Bang: Wormholes at the Dawn of the Universe

Panos Betzios , Paul Ghiringhelli , Ioannis D. Gialamas , Olga Papadoulaki
Authors on Pith no claims yet

Pith reviewed 2026-05-14 17:46 UTC · model grok-4.3

classification ✦ hep-th gr-qc
keywords Euclidean wormholesno-boundary proposalquantum cosmologyinitial conditionsholographyearly universewormhole saddles
0
0 comments X

The pith

Euclidean wormholes enlarge the semiclassical initial-condition landscape for the universe beyond the no-boundary proposal.

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

The paper proposes that Euclidean wormholes serve as additional contributions to the initial quantum state of the universe. This approach retains the use of Euclidean saddles to encode properties of cosmological wavefunctions but expands the range of regular geometries available for describing inflating universes. It addresses limitations in the Hartle-Hawking no-boundary proposal by offering a richer set of possibilities. A reader would find this relevant because it connects quantum gravity ideas to concrete early-universe models in a way that respects holographic principles.

Core claim

The principal achievement is that the wormhole program enlarges the semiclassical initial-condition landscape in a physically rich manner that conforms with holographic expectations, making it increasingly relevant for early-universe model building within UV complete theories of quantum gravity.

What carries the argument

Euclidean wormholes as candidate contributions to the Universe's initial quantum state, functioning as regular saddles in the path integral that broaden the class beyond the no-boundary proposal.

Load-bearing premise

Euclidean wormholes are physically relevant saddles in the quantum gravity path integral capable of contributing to the universe's initial state.

What would settle it

Detection of primordial gravitational waves or CMB patterns that match only the no-boundary proposal predictions while excluding wormhole contributions, or vice versa.

Figures

Figures reproduced from arXiv: 2605.13777 by Ioannis D. Gialamas, Olga Papadoulaki, Panos Betzios, Paul Ghiringhelli.

Figure 1
Figure 1. Figure 1: Schematic illustration of the wineglass wormhole proposal for the birth of the [PITH_FULL_IMAGE:figures/full_fig_p002_1.png] view at source ↗
Figure 2
Figure 2. Figure 2: Schematic illustration of the no-boundary proposal for the birth of the Universe. [PITH_FULL_IMAGE:figures/full_fig_p006_2.png] view at source ↗
read the original abstract

This essay discusses recent progress on Euclidean wormholes as candidate contributions to the Universe's initial quantum state. The comparison with the Hartle-Hawking no-boundary proposal highlights both a conceptual affinity and genuine advance: wormholes retain the relevance of Euclidean-saddles as encoders of properties of cosmological wavefunctions, while they broaden the class of regular saddles that are physically relevant for inflating universes and are capable of resolving issues that plague the no-boundary proposal. The principal achievement of the wormhole program is to enlarge the semiclassical initial-condition land-scape in a way that is physically rich, conforms with Holographic expectations and as such becomes increasingly relevant for early-universe model building, within UV complete theories of quantum gravity.

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, simulated authors' rebuttal, and a circularity audit. Tearing a paper down is the easy half of reading it; the pith above is the substance, this is the friction.

Referee Report

0 major / 1 minor

Summary. This essay discusses recent progress on Euclidean wormholes as candidate contributions to the Universe's initial quantum state. It compares this approach to the Hartle-Hawking no-boundary proposal, highlighting both conceptual similarities and advances: wormholes broaden the class of regular semiclassical saddles that are physically relevant for inflating universes, help resolve issues in the no-boundary proposal, and enlarge the semiclassical initial-condition landscape in a manner consistent with holographic expectations, thereby becoming relevant for early-universe model building within UV-complete theories of quantum gravity.

Significance. If the perspective holds, the work is significant in that it synthesizes and advances the conceptual framework for using Euclidean wormholes in cosmological initial conditions. This could provide a richer set of physically relevant saddles compared to the no-boundary proposal, aligning with holographic principles and offering new avenues for model building in quantum gravity.

minor comments (1)
  1. [Abstract] The abstract is quite dense with technical terminology; expanding the final sentence to briefly list one or two concrete examples of wormhole configurations or resolved no-boundary issues would improve accessibility without altering the essay's scope.

Simulated Author's Rebuttal

0 responses · 0 unresolved

We thank the referee for their positive and accurate summary of our essay, as well as for recommending minor revision. The referee correctly identifies the central advance: Euclidean wormholes enlarge the space of regular semiclassical saddles relevant for inflating cosmologies while preserving the utility of Euclidean saddles for encoding wavefunction properties and aligning with holographic expectations. No specific major comments were raised in the report.

Circularity Check

0 steps flagged

No significant circularity in the derivation chain

full rationale

The manuscript is a qualitative essay summarizing conceptual progress on Euclidean wormholes as contributions to the initial quantum state. It contrasts them with the Hartle-Hawking proposal and states that wormholes enlarge the space of regular semiclassical saddles while remaining compatible with holographic expectations. No new quantitative derivation, wave-function computation, or stability analysis is presented; the central claim is a descriptive synthesis of how the wormhole program broadens the initial-condition landscape. No equations or fitted parameters appear that reduce by construction to the paper's own inputs, and no load-bearing step relies on a self-citation chain whose validity is presupposed within the text itself. The discussion therefore remains self-contained against external benchmarks and receives the default non-circularity finding.

Axiom & Free-Parameter Ledger

0 free parameters · 0 axioms · 0 invented entities

Abstract-only review; no explicit free parameters, axioms, or invented entities are stated in the provided text.

pith-pipeline@v0.9.0 · 5430 in / 971 out tokens · 33459 ms · 2026-05-14T17:46:31.873146+00:00 · methodology

discussion (0)

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Reference graph

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