Distortion Gravity
Type |
Metric-affine gravity theory |
|---|---|
Proposed by |
Luca Eliseo Pavesi (2026) |
Core fields |
Metric tensor gμν, Distortion tensor Dρμν |
Propagating degrees |
Massless graviton, trace vector Vμ, axial vector aμ |
Key properties |
Ghost‑free unitarity, dynamical torsion, ER = EPR realisation |
Scope |
Quantum gravity, alternative relativity, wormholes |
Distortion Gravity (DG) is a metric‑affine theory of gravity proposed by Luca Eliseo Pavesi in 2026. It extends general relativity by promoting the affine connection Γρμν to an independent dynamical field, whose deviation from the Levi‑Civita connection Γ̃ρμν is quantified by the distortion tensor Dρμν. The theory propagates a massless graviton and two massive vector fields – the trace vector Vμ and the axial torsion vector aμ – and has been shown to be ghost‑free.
Distortion Gravity provides a four‑dimensional realisation of the ER = EPR conjecture: the distortion tensor that sustains a traversable wormhole (ER bridge) also governs quantum entanglement (EPR) through the quantised flux of the axial torsion.
The theory was first presented in a series of four articles published on ScienceOpen in 2026, which were subsequently reviewed and indexed by Sciety (eLife). The foundational article on ghost‑free unitarity received two recommendations on ResearchGate. An expanded monograph, Distortion Gravity: A New Theory of Gravitation: From Foundations to Complete Verification, was published as a book in June 2026 (ISBN 979‑8181642256).
__FORCETOC__
The distortion tensor and its vectors
In metric‑affine geometry the distortion tensor is defined as
Dρμν = Γρμν − Γ̃ρμν, encoding both torsion Tρμν = Dρμν − Dρνμ and non‑metricity Qρμν = ∇ρgμν.
Under the general linear group GL(4,ℝ), Dρμν decomposes into irreducible parts. The dynamical sector consists of two vectors:
$$V_\mu = D^\alpha{}_{\mu\alpha}, \qquad a_\mu = \frac{1}{6}\varepsilon_{\mu\nu\rho\sigma} D^{\nu\rho\sigma}.$$
Action
The ghost‑free action for Distortion Gravity is
$$S_{\text{DG}} = \int d^4x \sqrt{-g} \left[ \frac{1}{2\kappa} \tilde{R} + \mathcal{L}_V + \mathcal{L}_a + \alpha_1 I_1 + \alpha_2 I_2 + \alpha_3 I_3 \right],$$ where R̃ is the Riemann scalar of the Levi‑Civita connection, ℒV and ℒa are Proca Lagrangians for the trace and axial vectors, and I1, 2, 3 are quadratic invariants of Dρμν.
Field equations
The field equations are obtained by varying the action with respect to the metric and the vector fields.
Variation with respect to the metric
The Einstein–Hilbert term yields the Einstein tensor G̃μν. The Proca kinetic and mass terms for a generic vector Bμ give
$$\frac{2}{\sqrt{-g}}\frac{\delta}{\delta g^{\mu\nu}}\left(-\frac{1}{4}\sqrt{-g}F_{\alpha\beta}F^{\alpha\beta}\right)=F_{\mu\alpha}F_\nu^{\ \alpha}-\frac{1}{4}g_{\mu\nu}F_{\alpha\beta}F^{\alpha\beta},$$
$$\frac{2}{\sqrt{-g}}\frac{\delta}{\delta g^{\mu\nu}}\left(\frac{1}{2}\sqrt{-g}m^2B_\alpha B^\alpha\right)=m^2\left(B_\mu B_\nu-\frac{1}{2}g_{\mu\nu}B_\alpha B^\alpha\right).$$
Applying these to Vμ and aμ, the metric field equation is
G̃μν = κ(Tμνmatter+Tμν(V)+Tμν(a)+Tμν(pot)), where the Proca stress–energy tensors are
$$T^{(V)}_{\mu\nu}=F^{(V)}_{\mu\alpha}F^{(V)\alpha}_{\ \ \ \nu}-\frac{1}{4}g_{\mu\nu}F^{(V)}_{\alpha\beta}F^{(V)\alpha\beta}+m_V^2\left(V_\mu V_\nu-\frac{1}{2}g_{\mu\nu}V_\alpha V^\alpha\right),$$ and similarly for Tμν(a).
Variation with respect to the vector fields
Varying with respect to Vμ and aμ yields the Proca equations in curved spacetime:
$$\tilde{\nabla}_\mu F^{(V)\mu\nu}+m_V^2V^\nu=0,\qquad \tilde{\nabla}_\mu f^{(a)\mu\nu}+m_a^2a^\nu=0.$$ Taking the divergence gives the Lorenz conditions $\tilde{\nabla}_\mu V^\mu=0$ and $\tilde{\nabla}_\mu a^\mu=0$.
Linearised equations
Expanding around Minkowski space (gμν = ημν + hμν, Dρμν = 0 + dρμν), the linearised field equations are
□Vμ + mV2Vμ = 0, □aμ + ma2aμ = 0, ∂μVμ = 0, ∂μaμ = 0. In Fourier space this gives the dispersion relation ω2 = k2 + m2, confirming 3 degrees of freedom for each massive vector.
Spontaneous symmetry breaking
For a homogeneous configuration $V_\mu = (V_0, \vec 0)$, the potential is
$$V(V_0) = \frac{1}{2} m_V^2 V_\mu V^\mu + \frac{\lambda_V}{4} (V_\mu V^\mu)^2 = -\frac{1}{2} m_V^2 V_0^2 + \frac{\lambda_V}{4} V_0^4,$$ using the metric signature (−,+,+,+). When mV2 < 0 the potential has a double‑well shape with minima at V0 = ± v, where $v = \sqrt{|m_V^2|/\lambda_V}$. The Levi‑Civita point V0 = 0 becomes a saddle point.
In curved spacetime the effective mass becomes curvature‑dependent,
$$m_{V,\text{eff}}^2(r) = m_V^2 + \lambda_{\text{curv}} \frac{r_0^2}{r^2},$$ with λcurv > 0 and r0 the wormhole throat radius. Near the throat (r ∼ r0) the mass squared is negative (SSB phase), while far away (r ≫ r0) it is positive (symmetry restored). This localises the NEC violation at the throat and recovers GR asymptotically.
Modified ansatz
A static, spherically symmetric wormhole is described by the metric
$$ds^2 = - e^{2\Phi(r)} dt^2 + \frac{H(r)}{e^{2\Phi(r)}\left(1 - \frac{b(r)}{r}\right)} dr^2 + r^2(d\theta^2 + \sin^2\theta\, d\phi^2),$$ where Φ(r) is the finite redshift function, b(r) the shape function with b(r0) = r0, and H(r) a curvature‑dependent compression factor,
H(r) = 1 + λ(r)(e2Φ(r) − 1), with λ(r) a double Gaussian localised at the throat:
$$\lambda(r) = A_1 \exp\!\left(-\frac{(r - r_0)^2}{2\sigma_1^2}\right) + A_2 \exp\!\left(-\frac{(r - r_1)^2}{2\sigma_2^2}\right).$$
When Φ(r) < 0 (gravitational blueshift) near the throat, e2Φ < 1 and H(r) < 1, compressing the proper distance. The double Gaussian allows independent control of the throat and the region where b(r)/r approaches unity, preventing the wormhole from pinching off.
This metric has been discussed in the context of the Italian Wikipedia entry for the Einstein–Rosen bridge, where its anisotropic and entropic features are described in relation to the Orch‑OR paradigm.
Field equations
The Einstein equations with the Proca energy‑momentum tensors yield
$$b'(r) = \kappa r^2 \rho(r), \qquad \Phi'(r) = \frac{b(r)/r + \kappa r^2 p_r(r)}{2r(1 - b(r)/r)},$$ where ρ(r) and pr(r) are the total energy density and radial pressure. The Proca equations for the vector fields in the wormhole background are
$$V_0'' + \left(\frac{2}{r} + \frac{H'}{2H}\right) V_0' - \frac{m_{V,\text{eff}}^2(r)}{g^{-1}_{rr}} V_0 + \frac{\lambda_V}{g^{-1}_{rr}} V_0^3 = 0,$$
$$a_\phi'' + \left(\frac{H'}{2H} + \frac{2}{r}\right) a_\phi' - \frac{m_{a,\text{eff}}^2(r)}{g^{-1}_{rr}} a_\phi + \frac{\lambda_a}{r^2 g^{-1}_{rr}} a_\phi^3 = 0,$$ with grr−1 = e2Φ(1−b/r)/H(r).
Numerical exploration
The coupled system was solved numerically using the SciPy `solve_ivp` routine (RK45). A total of 7,600 configurations were tested over a 13‑dimensional parameter space. A wormhole is considered valid if it satisfies: throat condition, flaring‑out, openness (b(r) < r for all r > r0), traversability (proper crossing time Δτ < πr0), and angular stability. 57% of the configurations yielded fully valid traversable wormholes, with the best crossing time Δτ = 0.1035 r0/c, about three times shorter than the GR collapse timescale πr0. The NEC is violated at the throat and restored asymptotically.
== ER = EPR realisation ==
Entanglement entropy and axial torsion flux
In Distortion Gravity, the effective Newton constant is modified by the background vector fields,
$$G_{\text{eff}} = \frac{G_N}{1 + \alpha V_\mu V^\mu + \beta a_\mu a^\mu}.$$ The entanglement entropy across the wormhole is given by the Ryu–Takayanagi formula
$$S_{\text{EE}} = \frac{A_{\text{throat}}}{4 G_{\text{eff}}} = \frac{\pi r_0^2}{G_{\text{eff}}}.$$
The axial torsion field aμ generates a quantised flux through the throat,
Φ = ∮S1aμdxμ = 2πaϕ(r0) = 2πnvar0, n ∈ ℤ.
The entanglement entropy is proportional to this flux,
SEE ∝ Φ. Thus both the geometric connectivity (wormhole area) and the quantum correlations (entanglement) are controlled by the same integer n.
Quantum simulation
The ER = EPR mechanism was tested on the Qiskit platform using a two‑qubit circuit. A Bell state was prepared and subjected to Aharonov–Bohm phase shifts determined by the torsion flux. The von Neumann entropy remained maximal (SEE = 1 bit) for all integer winding numbers n = 0, …, 5, confirming that torsion preserves quantum correlations. A CHSH Bell test showed a continuous modulation of Bell violations by the torsion gradient, without any violent “firewall”.