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arxiv: 2510.24800 · v2 · submitted 2025-10-27 · ✦ hep-ph · astro-ph.SR· gr-qc· hep-th

Weak interactions and the gravitational collapse

Domenec Espriu This is my paper

Pith reviewed 2026-05-18 02:41 UTC · model grok-4.3

classification ✦ hep-ph astro-ph.SRgr-qchep-th
keywords weak interactionsgravitational collapsecompact objectsZ bosonequation of stateneutron starsexotic starsZeldovich
0
0 comments X p. Extension

The pith

Weak force pressure from Z exchange can stabilize compact objects of 10^{-3} solar masses and a few meters radius.

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

The paper proposes that the chart of nuclei and compact objects can include a new branch of bodies with large weak charge. These objects would form when gravity drives matter to ultrahigh densities where the weak interaction via Z exchange generates enough pressure to prevent further collapse. The resulting configurations have masses around one-thousandth of a solar mass and radii of only a few meters, placing them just outside their Schwarzschild radius. This setup would realize the equation of state suggested by Zeldovich, with the weak force taking over the role normally played by degeneracy pressure in ordinary neutron stars.

Core claim

The central claim is that gravitational collapse can produce stable objects sustained by the pressure of the weak force due to Z exchange. At extreme densities this interaction, normally negligible, becomes dominant and supports configurations with large weak charge, masses of order 10^{-3} solar masses, and radii of a few meters that lie only slightly above their Schwarzschild limit.

What carries the argument

The pressure generated by the weak force due to Z exchange, which becomes dominant at ultrahigh densities reached through gravitational collapse.

If this is right

  • These objects would represent a distinct class of very compact bodies, only slightly larger than their Schwarzschild radius.
  • The weak force would replace degeneracy pressure as the main stabilizing mechanism.
  • The configurations would constitute a physical realization of the Zeldovich equation of state.
  • Such objects could form an additional branch alongside nuclei and neutron stars in the chart of compact matter.

Where Pith is reading between the lines

These are editorial extensions of the paper, not claims the author makes directly.

  • Detection of these objects would require new searches focused on their specific mass and compactness range.
  • The idea links particle-physics interactions directly to the end states of gravitational collapse.
  • Similar mechanisms might be explored for other forces or particles at extreme densities.

Load-bearing premise

The weak interaction via Z exchange produces sufficient outward pressure to balance gravity at the densities needed for these compact sizes.

What would settle it

A calculation showing that Z-exchange pressure falls short of supporting the claimed mass-radius combination, or the absence of any astrophysical signatures consistent with objects of 10^{-3} solar masses and radii of a few meters.

Figures

Figures reproduced from arXiv: 2510.24800 by Domenec Espriu.

Figure 1
Figure 1. Figure 1: FIG. 1: On the left panel we plot the tree-level potential [PITH_FULL_IMAGE:figures/full_fig_p006_1.png] view at source ↗
Figure 2
Figure 2. Figure 2: FIG. 2: Comparison between the energy density profiles of the relativistic and newtonian solutions [PITH_FULL_IMAGE:figures/full_fig_p020_2.png] view at source ↗
Figure 3
Figure 3. Figure 3: FIG. 3: The figure shows the dependence of the mass of the star (in units of the solar mass) [PITH_FULL_IMAGE:figures/full_fig_p021_3.png] view at source ↗
read the original abstract

The chart of nuclei could be enlarged with a branch describing neutron stars that are huge nuclei of a few solar masses held together by gravity force and sustained by the pressure due to the degenerate Fermi sea. We contend in this manuscript that yet another branch could be added: objects with a large weak charge, with masses around $10^{-3}$ solar masses and having radii of a few meters, very compact, only slightly larger than their Schwarzchild radius, and sustained by the pressure generated by the weak force due to $Z$ exchange. This interaction, insignificant in normal neutron stars, could become dominant when ultrahigh densities are reached due to the action of gravity and lead to stable configurations if the appropriate conditions are met. They would constitute a physical realization of the equation of state proposed by Zeldovich some decades ago.

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

1 major / 1 minor

Summary. The manuscript proposes extending the analogy between nuclei and neutron stars by adding a new class of compact objects with large weak charge. These objects would have masses around 10^{-3} solar masses, radii of a few meters (slightly larger than their Schwarzschild radius), and be stabilized by pressure arising from Z-boson exchange in the weak interaction at ultrahigh densities, thereby realizing an equation of state previously suggested by Zeldovich.

Significance. If substantiated with quantitative support, the proposal would identify a novel regime of matter where weak neutral currents provide the dominant stabilizing pressure against gravitational collapse, potentially relevant for extreme-density astrophysics and offering a physical realization of Zeldovich's equation of state. The conceptual link between nuclear structure and gravitational objects is a strength, though the absence of any derivation or estimate currently prevents assessment of physical viability.

major comments (1)
  1. [Abstract] Abstract: the assertion that weak-force pressure due to Z exchange can sustain stable configurations at M ≈ 10^{-3} M_⊙ and R of a few meters (implying densities ≳ 10^{17}–10^{18} kg m^{-3}) is unsupported by any effective equation of state, scaling estimate from the weak neutral-current Hamiltonian, or insertion into the Tolman-Oppenheimer-Volkoff equation. No demonstration is given that this term dominates degeneracy pressure or other contributions under the stated conditions.
minor comments (1)
  1. [Abstract] The abstract would be strengthened by a single sentence indicating the order-of-magnitude estimate or coupling (e.g., G_F) that motivates the dominance of Z exchange at the claimed densities.

Simulated Author's Rebuttal

1 responses · 0 unresolved

We thank the referee for the careful reading and constructive comments on our manuscript. We address the major comment below and will incorporate quantitative support in a revised version.

read point-by-point responses

  1. Referee: [Abstract] Abstract: the assertion that weak-force pressure due to Z exchange can sustain stable configurations at M ≈ 10^{-3} M_⊙ and R of a few meters (implying densities ≳ 10^{17}–10^{18} kg m^{-3}) is unsupported by any effective equation of state, scaling estimate from the weak neutral-current Hamiltonian, or insertion into the Tolman-Oppenheimer-Volkoff equation. No demonstration is given that this term dominates degeneracy pressure or other contributions under the stated conditions.

    Authors: We agree that the abstract states the conceptual proposal without explicit derivations or estimates. The manuscript is intended as a short note highlighting a possible extension of the nuclei-neutron star analogy to objects stabilized by weak neutral currents at extreme densities, realizing Zeldovich's equation of state. In the revision we will add a dedicated section with scaling estimates derived from the weak neutral-current Hamiltonian, showing the density threshold at which Z-exchange pressure overtakes degeneracy pressure. We will also provide a qualitative discussion of the resulting equation of state and its insertion into the Tolman-Oppenheimer-Volkoff equation to demonstrate the existence of stable configurations near the quoted mass and radius. revision: yes

Circularity Check

0 steps flagged

No derivation chain or self-referential steps present in abstract

full rationale

The abstract proposes compact objects stabilized by Z-exchange pressure but supplies no equations, effective Lagrangian, TOV integration, or scaling estimates. It explicitly attributes the underlying equation of state to Zeldovich's prior external work rather than deriving or fitting it internally. No self-citations, fitted parameters renamed as predictions, or ansatzes appear. The text is therefore self-contained against external benchmarks with no load-bearing step that reduces to its own inputs by construction.

Axiom & Free-Parameter Ledger

0 free parameters · 1 axioms · 1 invented entities

Abstract-only content provides no explicit free parameters, axioms, or invented entities beyond the standard assumption that weak interactions and general relativity remain valid at the cited densities; the central claim therefore rests on the unquantified expectation that Z-exchange pressure can dominate and stabilize the configuration.

axioms (1)
  • domain assumption Weak interactions via Z exchange and general relativity remain applicable at the ultrahigh densities reached in gravitational collapse.
    The proposal assumes standard-model weak physics and Einstein gravity continue to hold without modification in the new regime.
invented entities (1)
  • Compact objects with large weak charge no independent evidence
    purpose: To describe stable configurations sustained by weak-force pressure at extreme densities.
    These objects are postulated as a new branch of nuclei-like structures; no independent falsifiable signature is supplied in the abstract.

pith-pipeline@v0.9.0 · 5643 in / 1443 out tokens · 62301 ms · 2026-05-18T02:41:09.222712+00:00 · methodology

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Lean theorems connected to this paper

Citations machine-checked in the Pith Canon. Every link opens the source theorem in the public Lean library.

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extends
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Reference graph

Works this paper leans on

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