Thermodynamic Extension of Q-Field Geometry: A Relative-Entropy Action for Emergent Gravity
Working technical paper v0.1
Viktor Stefanov Pronchev — independent research working draft
For discussion within the BSM-SG/QFG research program
20 July 2026
|
Scientific status: This manuscript proposes a
mathematical extension and a falsifiable research program. It does not claim
that QFG, BSM-SG, or the proposed entropy sector has been experimentally
established. |
Abstract
Q-Field Geometry (QFG) models matter as stable field-geometric and topological configurations of a complex two-component field, a U(1) gauge sector, and an internal orientation field. Gravity from Entropy (GfE), developed independently, models gravity as emerging from quantum geometric relative entropy between the physical spacetime metric and a matter-and-curvature-induced metric. This paper constructs a conservative bridge between these approaches. We retain the minimal QFG field Lagrangian and add a relative-entropy sector that compares the physical metric with a metric induced by the QFG state. The resulting action is proposed as an effective thermodynamic extension, not as a completed fundamental theory. We define a local entropy density, an effective first-law relation, a topological work term, and conditions under which general relativity is recovered in the weak-field and low-curvature limit. The framework produces testable targets in high-Q resonators, topological soliton simulations, and cosmology. Its central hypothesis is that local coherent structures can emerge as low-entropy-density QFG nodes while total entropy continues to increase globally.
1. Motivation and scope
The emergence of galaxies, stars, atoms, molecules, and living systems appears at first sight to conflict with the second law of thermodynamics. The conflict is only apparent: local order can increase when entropy is exported or when the accessible volume grows sufficiently rapidly. The 2026 thermodynamic analysis of Gravity from Entropy sharpened this statement by identifying a regime in which total entropy grows while entropy per unit physical volume decreases. In parallel, QFG has been developed as a field-first framework in which localized matter corresponds to stable coherent or topological configurations rather than point particles.
The purpose of this paper is not to identify QFG with GfE. Their starting ontologies differ. The purpose is to construct the smallest mathematically explicit extension in which the informational tension used by GfE can become a thermodynamic coarse-graining of the underlying QFG field state.
2. Conceptual comparison: GfE, QFG, and BSM-SG
|
Aspect |
Gravity from Entropy |
Q-Field Geometry |
BSM-SG role in the proposed
hierarchy |
|
Primary
ontology |
Physical
metric and matter/curvature-induced metric |
Fields Ψ, Aμ,
density ρ, and orientation n |
Candidate
microscopic substrate: Cosmic Lattice and SG interactions |
|
Core
dynamical object |
Quantum
geometric relative entropy |
Field/topological
Lagrangian |
Energy wells,
SG balance, lattice synchronization |
|
Matter |
Induces an
alternative geometry |
Stable
topological/coherent nodes |
Structured
helical and lattice formations |
|
Gravity |
Information-theoretic
tension between metrics |
Response of
geometry to Q-field energy-information density |
Macroscopic
manifestation of SG/CL-space dynamics |
|
Low-energy
limit |
General
relativity |
Required
consistency condition |
Expected
effective continuum behavior |
|
Main test
domain |
Cosmology and
gravitational thermodynamics |
Resonators,
particles, atoms, materials, gravity |
Microscopic
and structural ontology |
The proposed hierarchy is therefore:
BSM-SG microscopic substrate → QFG field dynamics → entropic emergent geometry.
|
Interpretive boundary: This hierarchy is a research
hypothesis proposed here. It is not asserted by the authors of Gravity from
Entropy and should not be represented as a collaboration or endorsement. |
3. Minimal QFG field sector
We retain the minimal QFG field content already used in the QFG program:
· Complex two-component field Ψ ∈ C².
· Vacuum or field density ρ = Ψ†Ψ.
· U(1) gauge field Aμ with Fμν = ∂μAν − ∂νAμ.
· Orientation field n = (Ψ†σΨ)/(Ψ†Ψ) ∈ S².
· Potential minimum at a background density ρ0.
· Topological stiffness of the orientation texture.
L_QFG = 1/2 |D_μΨ|² − 1/4 Z(ρ)F_μνF^μν − κ/4 (∂_μn × ∂_νn)² − λ(ρ − ρ₀)² − U(n).
Here Dμ = ∇μ + iqAμ. The field equations follow from δS/δΨ = 0, δS/δAμ = 0, and the constrained variation of n. The stress-energy tensor is defined conventionally by metric variation:
T_μν^QFG = −(2/√−g) δ(√−g L_QFG)/δg^μν.
This field sector supplies localized energy, orientation texture, gauge response, and topological charge. It does not yet specify a complete microscopic derivation of the spacetime metric.
4. QFG-induced metric
We introduce an effective metric induced by the local QFG state. The lowest-order covariant ansatz is
g̃_μν^Q = g_μν + a₁ T_μν^QFG/M_*⁴ + a₂ ∇_μρ ∇_νρ/M_*⁶ + a₃ X_μν(n)/M_*⁴ + a₄ J_μJ_ν/M_*⁶ + …
where M* is the coarse-graining scale, Jμ is the U(1) current, and Xμν(n) is an orientation-texture tensor, for example
X_μν(n) = ∂_μn · ∂_νn − 1/2 g_μν(∂_αn · ∂^αn).
The coefficients ai must be calibrated or bounded experimentally. This induced metric is not introduced as a second independently propagating spacetime. It is the geometry preferred by the local QFG state after coarse-graining.
5. Making relative entropy mathematically admissible
A Lorentzian metric is not a density matrix and cannot be inserted naively into the quantum relative-entropy formula. A local positive geometric operator must first be constructed. We therefore select a timelike observer uμ and a spatial tetrad on each local hypersurface. The physical and QFG-induced spatial metrics define positive normalized operators G and GQ:
G = γ/Tr(γ), G_Q = γ̃_Q/Tr(γ̃_Q), G > 0, G_Q > 0, Tr(G)=Tr(G_Q)=1.
The local QFG geometric relative entropy is then defined as
D_Q(G || G_Q) = Tr[G(log G − log G_Q)] ≥ 0.
This observer-dependent local construction is sufficient for an effective thermodynamic theory. A fully covariant operator definition is left as an open mathematical problem.
|
Key improvement: Defining positive normalized
spatial operators avoids the category error of treating Lorentzian metrics
directly as quantum density matrices. |
6. Proposed extended action
The thermodynamic QFG action is proposed as
S_QFG-T = ∫ d⁴x √−g [ M_P²R/2 + L_QFG − ξ M_*⁴ D_Q(G || G_Q) + L_m,ext ].
The terms have distinct roles:
· Einstein-Hilbert term: establishes the conventional low-energy gravitational baseline.
· QFG field term: produces gauge, density, orientation, resonance, and topological dynamics.
· Relative-entropy term: penalizes mismatch between physical spatial geometry and geometry preferred by the QFG state.
· External matter term: allows conventional fields not yet represented by Ψ.
The entropy coupling ξ is dimensionless in this normalization. Setting ξ = 0 returns the minimal QFG-plus-GR effective theory. The extended theory is therefore nested and falsifiable.
7. Field equations and weak-limit behavior
Variation with respect to the physical metric gives schematically
M_P² G_μν = T_μν^QFG + T_μν^ext + T_μν^ent,
where
T_μν^ent = −2ξM_*⁴/√−g · δ[√−g D_Q(G||G_Q)]/δg^μν.
Variation with respect to Ψ, Aμ, and n produces the original QFG equations plus backreaction terms from the induced metric and entropy functional.
For a small mismatch ΔG = G − GQ, relative entropy has a quadratic expansion:
D_Q(G||G_Q) = 1/2 ⟨ΔG, K_GQ⁻¹ ΔG⟩ + O(ΔG³).
Consequently, when curvature, QFG gradients, and metric mismatch are small, the entropy stress is second order and the equations reduce continuously to general relativity with the ordinary QFG stress-energy tensor. This is the required low-energy consistency condition.
8. Thermodynamic dictionary
On a foliation with local proper volume element dV = √γ d³x, define
s_Q = ξ M_*³ D_Q(G||G_Q),
u_Q = T_μν^QFG u^μu^ν + u_ent,
S_Q(V) = ∫_V s_Q dV.
A local effective first law is proposed in differential form:
du_Q = T_eff ds_Q − p_eff d(ln√γ) + μ_H dq_H + dW_drive.
Here qH is a topological charge such as a Hopf invariant, μH is its conjugate topological chemical potential, and dWdrive denotes externally injected RF, optical, mechanical, or other coherent work. For a stationary isolated node, dWdrive = 0.
|
Quantity |
Proposed definition |
Physical interpretation |
|
sQ |
ξM*³ DQ |
Local
geometric-information entropy density |
|
uQ |
QFG plus
entropy energy density |
Internal
energy available to the coherent structure |
|
Teff |
(∂uQ/∂sQ)V,qH |
Effective
temperature of geometric degrees of freedom |
|
peff |
−∂UQ/∂V |
Effective
pressure of the QFG/entropy sector |
|
μH |
∂UQ/∂qH |
Energy cost
of changing topological sector |
|
Wtopo |
∫ μH dqH |
Work required
to create, deform, or destroy a node |
9. Local order and the second law
The thermodynamic scenario of interest is
dS_total/dt ≥ 0, while d(S_Q/V)/dt < 0 in a growing or entropy-exporting domain.
In QFG language, a stable node corresponds to a local reduction in accessible geometric configurations, accompanied by energy and entropy transfer to the environment or by growth of the containing physical volume. A coherence boundary can therefore form without violating the second law.
The proposed sequence is
global phase-space growth → local reduction of geometric uncertainty → coherence boundary → stable topological node.
This is a thermodynamic reinterpretation of the QFG-Atlas picture in which a central field node is surrounded by a finite coherence region that relaxes into the background density ρ0.
10. Cosmological reduction
For a spatially flat Friedmann-Robertson-Walker metric,
ds² = −dt² + a(t)² d x²,
a homogeneous QFG background Ψ(t) induces an isotropic spatial operator GQ(t). The entropy sector contributes an effective density and pressure:
3M_P²H² = ρ_m + ρ_QFG + ρ_ent,
−2M_P²Ḣ = ρ_m+p_m + ρ_QFG+p_QFG + ρ_ent+p_ent.
The effective equation-of-state parameter went(z) = pent/ρent is not assumed. It is calculated after specifying the induced metric coefficients and solving the QFG background. A dynamical dark-energy-like term is therefore possible, but not guaranteed.
11. Falsifiable predictions
|
Test |
QFG-T prediction |
Conventional controls |
Falsifier |
Status |
|
High-Q RF
cavity |
Residual
frequency shift scales with stored energy density and geometry after thermal
correction. |
Temperature,
mechanical strain, dielectric loss, source pulling. |
No
reproducible residual across geometries and powers. |
Near-term |
|
Two-tone HRM
cavity |
Entropy proxy
and phase noise exhibit a threshold-like locking region not captured by
calibrated Kerr/Duffing dynamics. |
Intermodulation,
injection locking, nonlinear loss, amplifier compression. |
All
signatures reproduced quantitatively by conventional nonlinear RF model. |
Near-term |
|
Topological-node
simulation |
Stable qH
sectors show lower local DQ and a finite topological work barrier. |
Numerical
resolution, damping, boundary conditions. |
No
convergence or no distinct entropy minimum by topological sector. |
Immediate
computational |
|
Optical/MEMS
resonator |
Geometry-dependent
linewidth or phase stabilization remains after material-loss model. |
Thermo-optic,
photothermal, clamping, TLS and nonlinear losses. |
Residual
vanishes with complete conventional model. |
Medium-term |
|
Atomic/ion
metrology |
Correlated
micro-shifts depend on cavity energy density and geometry, not only atomic
variables. |
AC Stark,
Zeeman, blackbody, micromotion, collisions. |
No
cross-platform correlated residual. |
Long-term |
|
Cosmology |
Derived
went(z) and entropy-density evolution fit expansion and structure data with
fewer or constrained free parameters. |
ΛCDM,
modified gravity and selection effects. |
No parameter
region satisfies background plus perturbation constraints. |
Long-term |
12. Numerical program
A staged numerical implementation is recommended:
1. Level 1: One-dimensional and axisymmetric QFG node with fixed flat metric; calculate energy, qH proxy, and coherence boundary.
2. Level 2: Construct GQ from Tμν, ∇ρ, and Xμν(n); calculate DQ on spatial slices.
3. Level 3: Minimize total energy plus entropy penalty and compare topological sectors.
4. Level 4: Couple weak metric perturbations hμν and verify recovery of the Newtonian/GR limit.
5. Level 5: Homogeneous FRW reduction and calculation of ρent, pent, went, and entropy density.
6. Level 6: Bayesian calibration against cavity, atomic, or cosmological datasets with strict out-of-sample tests.
13. Relation to BSM-SG
The proposed thermodynamic extension is compatible with, but does not mathematically derive, the BSM-SG microscopic ontology. BSM-SG contributes three useful interpretive elements:
· Physical vacuum as a structured Cosmic Lattice rather than an empty background.
· Stable structures possessing finite energy wells and balances between internal vibrational and SG interaction energies.
· Synchronization and modulation of surrounding lattice states by ordered internal structures.
A future derivation would need to coarse-grain explicit BSM-SG lattice degrees of freedom into the QFG fields and then derive the induced metric and entropy functional. Until that derivation exists, BSM-SG should be presented as the candidate microscopic interpretation, QFG as the effective field model, and QFG-T as the proposed thermodynamic/gravitational extension.
14. Limitations and open problems
· The induced metric ansatz is not unique and introduces coefficients requiring calibration.
· The local relative entropy currently depends on a foliation or observer choice; a fully covariant positive-operator construction is unresolved.
· The entropy term may introduce higher derivatives or stability problems; ghost and hyperbolicity analyses are mandatory.
· No derivation from BSM-SG microscopic degrees of freedom has yet been completed.
· No experiment currently isolates a QFG entropy contribution from established electromagnetic, thermal, mechanical, quantum-optical, or gravitational effects.
· The cosmological dark-energy behavior is a possibility, not a result, until the reduced equations are solved.
· The theory must outperform simpler effective-field or modified-gravity explanations under model-selection penalties.
15. Conclusion
This paper proposes a minimal thermodynamic extension of Q-Field Geometry. The extension retains the established QFG field and topological sector, constructs a local metric preferred by the QFG state, and penalizes its informational mismatch with the physical geometry through a positive relative-entropy functional. In the weak-mismatch limit, general relativity is recovered. Outside that limit, the entropy sector may contribute effective pressure, internal energy, topological work, and potentially a dynamical cosmological component.
The central scientific claim is intentionally limited: the framework provides a coherent and falsifiable mathematical bridge between a field-topology theory of matter and an information-thermodynamic theory of emergent gravity. It does not yet establish that nature uses this bridge. The next decisive step is numerical implementation followed by controlled resonator and metrology tests.
Field energy + topological stress + geometric relative entropy → effective gravitational dynamics.
References
[1] Bianconi, G.. Thermodynamics of the gravity from entropy theory. Physical Review D (2026). DOI: 10.1103/26kn-thgp.
[2] Queen Mary University of London / Phys.org. How Gravity from Entropy theory connects the second law of thermodynamics with the emergence of cosmic structure, 17 July 2026.
[3] Bianconi, G.. Gravity from entropy: an information-theoretic approach to gravity (foundational GfE work).
[4] Pronchev, V. S.. QFGv2: Minimal QFG Lagrangian, resonator tests, and measurement program. Working document, 2026.
[5] QFG research program. QFG 2: field, gauge, topological, molecular, and experimental formalism. Working manuscript, 2026.
[6] QFG research program. QFG Atlas: field-geometric interpretations of atomic coherence structures. Working atlas, 2026.
[7] Sargoytchev, S.. Basic Structures of Matter - Supergravitation Unified Theory, third edition, 2025.
Online source: Phys.org article