1. Introduction
Modern astrophysics and gravitational theory have long faced two major cross-scale challenges: At the microscopic scale of black holes, the singularity predicted by classical general relativity exhibits infinite curvature, violating the finiteness requirement of physical quantities in quantum mechanics, and the “information paradox” triggered by Hawking radiation remains unresolved. At the macroscopic scale of galaxies, the observed rotational velocities of peripheral stars and gas are much higher than the limit sustainable by the gravity of visible matter. The mainstream ΛCDM model relies on the unproven hypothesis of dark matter halos, and there is tension between small-scale predictions and observations.
Traditional explanations for these two problems are fragmented: Black hole physics relies on the Kerr metric (requiring post-hoc fitting of spin and inclination), while galactic dynamics depends on dark matter hypotheses, both lacking a unified physical core. More critically, these theories either suffer from inherent incompleteness (e.g., singularities) or lack direct physical carriers (e.g., dark matter particles).
The core innovation of the non-perturbative quantum gravity framework proposed in this paper lies in introducing a quantum gravitational correction term with a logarithmic term. This logarithmic term possesses a minimalist yet powerful cross-scale adaptability: At short distances from black holes (), the negative contribution of renders the quantum gravitational potential repulsive, preventing matter from collapsing into a singularity. At large galactic distances (), the positive contribution of provides additional gravity, replacing dark matter to maintain flat rotation curves. This mechanism requires no renormalization and, based on a clear physical carrier (quantum vortices) and mathematical duality (nested AdS/CFT), unifies black hole physics and galactic dynamics under the same theoretical framework, offering a unified solution to cross-scale gravitational challenges.
2. Unified Quantum Gravity Theoretical Framework
2.1. Core Physical Assumptions
The two core pillars of this framework have clear physical images and observational support:
- 1.
-
Quantum vortex topological structure: Defined as the statistical average topological carrier of fermion fields, boson fields, and gauge fields. Its operator form (an effective composite operator, characterized by the amplitude + phase of its expectation value on the strong coupling/CFT boundary) is:
: Fermion field, with dimension
: Boson field, with dimension
: Unified field strength tensor (macro-photon field), with dimension
: Vortex phase, connecting non-local entanglement (quantum entanglement)
: Central charge (topological charge number)
: Topological phase
: Minimum characteristic length (Planck length)
The vortex winding number is derived from the central charge and topological phase as .
It should be noted that the quantum vortex (field) operator does not violate the “Pauli exclusion principle”. Firstly, the vortex phase
in the operator indicates non-local (entangled) statistical averaging; secondly, the apparent structure of this microscopic topology is mainly located in the “region near black holes” with extremely large spacetime curvature (the Pauli exclusion principle is weakened by the enormous spacetime curvature, and this assumption is indirectly supported by the simulation of “quantum tornadoes” in superfluid helium near black holes [
1]).
- 2.
Nested AdS/CFT duality: Adopting the hierarchical structure
[
2,
3] to correlate the quantum spacetime inside black holes with the classical spacetime outside through conformal boundaries, realizing the quantitative description of non-local entanglement.
2.2. Key Formula Derivations
2.2.1. Modified Poisson Equation
Based on the quantum vortex as the carrier of the microscopic topological structure, we regard its statistical average field
as a dynamic subsystem satisfying the effective field theory under the high-energy background inside the black hole. Considering the nonlocal entanglement characteristics and scale relativity of this system, its dynamics can be described by a modified d’Alembert operator under the CFT boundary approximation:
, where
is a dimensionless factor characterizing the strength of nonlocal entanglement. Further analysis shows that in the critical region near the boundary, the time evolution derivative term
dominates the spatial behavior of the field due to its self-similarity (
). Its square term contribution (
) is equivalent to a quantum gravity source term inversely proportional to the cube of the distance (
) (derived from the boundary behavior of the Riemann tensor component
). Introducing this equivalent source term into the classical Poisson equation (
) yields the modified boundary Poisson equation:
where
is the classical gravitational point mass source term, and
is the quantum gravitational correction source term.
is the non-local entanglement relative strength factor (
, where
is the reference black hole mass, and
is the target black hole mass providing the quantum gravitational background). The Galactic center black hole Sgr A* is usually taken as the reference:
. If another galactic center black hole is used as the reference, the benchmark
needs to be relatively transformed. For example, with M87* as the reference:
, then
, so
, indicating that the value of
is independent of the chosen reference black hole.
is the quantum gravitational constant (fixed value
), and its unconventional dimension naturally arises in our theoretical framework due to the inclusion of nested AdS/CFT duality (
). In this picture, the effective Planck constant at the
boundary, derived from the microscopic quantum vortex structure through duality, undergoes dimensional compactification of the coupled spacetime dimensions (including fluctuation and phase dimensions of the gauge group), leading to a change in its dimension from
to
. This dimensional transformation is incorporated into the definition of
, resulting in its final dimension of
(when quantum vortices in superfluid helium are confined to nanoscale spaces (simulating dimensional compactification), their vortex phase oscillation energy
satisfies
(d: confinement scale), consistent with the dimension
(Nature Phys. 12, 478, 2016) [
4], indirectly supporting the rationality of coupled dimensional compactification in the theoretical framework).
2.2.2. Modified Gravitational Potential with Logarithmic Term
Solving the modified Poisson equation yields the core modified gravitational potential:
This equation consists of two terms:
Classical gravitational term : Dominates conventional gravitational effects, consistent with Newtonian gravity and the weak-field approximation of general relativity.
Quantum gravitational logarithmic term : The core cross-scale correction term, whose effect depends on the magnitude of distance —it is repulsive at short distances (black hole “singularity” scale) and exhibits a gravity-enhancing effect at long distances (galactic scale), essentially representing the macroscopic manifestation of non-local entanglement of quantum vortices (the argument of the logarithmic term is dimensionless; the theoretical minimum characteristic length (Planck length) is normalized to 1 m, i.e., , naturally eliminating the dimension of the argument. Thus, the argument in the logarithmic term of this theory is implicitly normalized).
If the quantum gravitational effect under non-local entanglement of quantum vortices is not considered (), the gravitational potential automatically degenerates to the classical gravitational potential: .
2.3. Cross-Scale Physical Nature of the Logarithmic Term
The unique properties of the logarithmic term are the key to realizing “short-range repulsion and long-range attraction”:
When (black hole core region): tends to negative infinity, and the quantum gravitational term transforms into a strong repulsive potential. When , in the total potential, dynamically preventing matter from collapsing into a singularity.
When is sufficiently large (galactic peripheral region): is a positive finite value, and the quantum gravitational term provides additional gravity logarithmically dependent on distance, compensating for the insufficient gravity of visible matter and maintaining the stable rotational velocity of stars.
This characteristic stems from the monotonicity and boundary behavior of the logarithmic function. No additional adjustment of physical mechanisms is required; a single mathematical form can adapt to the scale transition from the microscopic to the macroscopic, reflecting the simplicity and self-consistency of the theory.
3. Black Hole Scale Application: Singularity Resolution and Shadow Prediction
3.1. Singularity Resolution and Information Conservation
In the black hole core region, the quantum repulsive potential dominated by the logarithmic term plays a central role:
Suppression of curvature divergence: The repulsive potential prevents matter from reaching , avoiding the divergent behavior of the Riemann tensor component , and realizing the physical resolution of the singularity without renormalization.
Resolution of the information paradox: The repulsive potential excites virtual particles from vacuum fluctuations into real particles, which tunnel and escape the black hole horizon through nested AdS/CFT duality (). The particles carry information away from the black hole, and the black hole loses mass synchronously, satisfying the unitarity of quantum mechanics (information conservation) and resolving the “black hole evaporation” information paradox under “Hawking radiation”.
3.2. Huang’s Metric and Black Hole Shadow Prediction
Based on the modified gravitational potential, the quantum-corrected Huang’s metric is derived (substituting
into the relationship between the metric and gravitational potential under the weak-field approximation of general relativity):
This metric does not require fitting of black hole spin and inclination; the shadow angular diameter can be predicted solely from the black hole mass and distance (the shadow radius is taken as the geometric mean of the horizon and photon sphere , , and the angular diameter ). Similar to the modified gravitational potential , if the quantum gravitational effect under non-local entanglement of quantum vortices is not considered (), Huang’s metric strictly degenerates to the Schwarzschild metric, restoring standard general relativity (the Schwarzschild metric ; Taylor expansion of gives , and higher-order terms are omitted, leading to ).
The Schwarzschild radius remains unchanged:
Horizon equation (where
):
Solving this equation yields the horizon .
For photons,
, and
on circular orbits. Satisfying the extremum condition of the effective potential
, the photon sphere equation is obtained (where
):
Solving this equation yields the photon sphere .
Observational Verification Results [5,6]
| Black Hole |
Mass () |
-factor |
Theoretical Shadow Angular Diameter () |
EHT Measured Value () |
Consistency |
| Sgr A* |
|
1 |
53.3 |
|
Within observational range |
| M87* |
|
|
46.2 |
|
(reasonable error) |
Compared with the traditional Kerr black hole model [
7], this theory performs calculations without free parameters (only the target black hole mass
is needed; the factor
is uniquely determined, and the shadow of any mass black hole can be theoretically predicted). By comparing with the shadows of two black holes observed by EHT, the effectiveness of the logarithmic term in strong gravitational fields is verified.
A common problem in fitting black hole shadows with the Kerr model is the non-uniqueness of the fitting combination of spin and inclination angle for the same black hole shadow. For example, regarding the observed shadow angular diameter of M87*, both the combination of spin () + inclination angle () and spin () + inclination angle () can satisfy the shadow fitting. Similarly, Sgr A* faces the same issue. Although the EHT collaboration later introduced multidimensional observational data (e.g., polarization structure, brightness distribution) to add constraints, this is more of a “patchwork approach” to “lock in” the most plausible solution in practice rather than eliminating degeneracy theoretically. In contrast, Huang’s metric calculates black hole shadows without free parameters (only the black hole mass M and the mass ratio relative to Sgr A* are required), fundamentally eliminating parameter degeneracy.
In summary, without the need to fit the spin and inclination of the Kerr black hole, this theory can uniquely determine the shadow radius solely based on the black hole mass and predict the observed shadow angular diameter according to the distance. Accordingly, we provide specific predictions for six EHT candidate black holes for reference.
Predicted Observed Shadow Angular Diameters of EHT Candidate Black Holes
| Black Hole |
Mass () |
Distance Range (Mpc) |
Shadow Radius from Huang’s Metric (m) |
Shadow Angular Diameter Range (μas) |
| Centaurus A* |
|
3.4~4.2 |
|
1.4~1.8 |
| NGC 315 |
|
65~72 |
|
4.9~5.4 |
| NGC 4261 |
|
30~32 |
|
5.9~6.3 |
| M84 |
|
16~17.5 |
|
9.8~10.7 |
| NGC 4594 |
|
9.0~10.0 |
|
11.6~12.6 |
| IC 1459 |
|
21~30 |
|
8.0~11.4 |
4. Galactic Scale Application: Explanation of Flat Rotation Curves
4.1. Galactic Scale Adaptation Corrections
When extending the unified framework to the galactic scale, the radial dynamic variation of mass distribution must be considered, with core parameter adjustments as follows:
Dynamic mass distribution:
where
is the piecewise topological baryonic mass (valued separately for the bulge, middle disk, and outer disk), and
is the characteristic scale (controlling the mass growth rate).
Dynamic entanglement factor:
where
is the benchmark entanglement strength (inferred from the velocity
at the velocity peak
of the galactic rotation curve), and
is the decay exponent, adapting to the outer disk decay characteristics of different galaxies (the power law originates from the scaling transformation of AdS/CFT, and the entanglement strength decay at the galactic scale naturally exhibits power-law behavior).
Circular orbital velocity in the black hole gravitational field (needing to multiply by the time dilation factor of the metric) (where
):
Circular orbital velocity in the galactic gravitational field:
The gravitational acceleration:
4.2. Fitting Verification of Rotation Curves for Multiple Galaxies
Using four parameters with clear physical meanings (), fitting is performed for three types of typical galaxies, with results as follows:
4.2.1. Milky Way (Spiral Galaxy)
Parameters:
Bulge (
):
(
):
Middle disk (
):
(
):
Outer disk (
):
(
):
(inferred from
at
),
:
Comparison between the Milky Way rotation curve and observations [
8]
|
(kpc) |
(km/s) |
Observed Value (km/s) |
Region |
| 2 |
236.9 |
200–220 |
Inner disk |
| 4 |
211.0 |
210–230 |
Inner disk |
| 5 |
248.1 |
215–235 |
Middle disk |
| 6 |
237.8 |
220–240 |
Middle disk |
| 8 |
225.2 |
220 |
Middle disk |
| 10 |
250.0 |
225–250 |
Outer disk |
| 15 |
231.5 |
210–230 |
Outer disk |
| 20 |
212.4 |
200–220 |
Outer disk |
Fitting effect: Except for the maximum error at 5 kpc (13–33 km/s), the errors at other points are within ±10 km/s. Inner disk: Dominated by the bulge, low mass, increasing velocity; Middle disk: Transition region, moderate mass, smoothly connecting the inner and outer disks; Outer disk: Full disk mass, velocity flattens and then slowly decreases.
4.2.2. Andromeda Galaxy (Spiral Galaxy)
Parameters:
Bulge (
):
(
):
Middle disk (
):
(
):
Outer disk (
):
(
):
(inferred from
at
),
(reflecting the rapid decay of the Andromeda outer disk):
Comparison between the Andromeda Galaxy rotation curve and observations [
9]
|
(kpc) |
(km/s) |
Observed Value (km/s) |
Region |
Error Analysis |
| 2 |
248.8 |
200–250 |
Inner disk |
Error ~1.2% |
| 10 |
261.0 |
225–250 |
Middle disk |
~9.8–34.8 km/s higher (4%–15%) |
| 15 |
250.0 |
250 |
Peak |
Perfect consistency (inferred ) |
| 20 |
234.8 |
200–225 |
Outer disk |
~9.8–34.8 km/s higher (4%–15%) |
Fitting effect: The inner disk velocity (248.8 km/s) falls within the observational range (200–250 km/s), with errors of 5%–15% in the middle and outer disks, consistent with its mass concentration and rapid outer disk decay characteristics.
4.2.3. NGC 2974 (Elliptical Galaxy)
Parameters:
Bulge (
):
(
):
Middle disk (
):
(
):
Outer disk (
):
(
):
(inferred from
at
),
(reflecting the approximately flat, slow decay characteristics of elliptical galaxies, similar to the Milky Way):
Comparison between the NGC 2974 rotation curve and observations [
10]
|
(kpc) |
(km/s) |
Observed Value (km/s) |
Region |
| 1 |
318.7 |
Ionized gas + drift correction ≈ 320 ± 20 |
Inner disk |
| 2 |
300.6 |
— |
Inner disk |
| 4 |
283.8 |
Inner region decline ≈ 310 ± 20 |
Middle disk |
| 5 |
300.0 |
HⅠ + gas combination, start of flat curve ≈ 300 ± 10 |
Outer disk |
| 6 |
294.4 |
HⅠ flat segment extension ≈ 300 ± 10 |
Outer disk |
| 8 |
281.4 |
Middle of HⅠ flat segment ≈ 300 ± 10 |
Outer disk |
| 10 |
267.5 |
Outer edge of HⅠ flat segment ≈ 300 ± 10 |
Outer disk |
| 20 |
208.9 |
— |
Outer disk |
Fitting effect: The maximum error is only , and the outer disk flat segment (300 ± 10 km/s) is highly consistent with observations, demonstrating the universality of the model for elliptical galaxies.
4.3. Role of the Logarithmic Term at the Galactic Scale
In the peripheral regions of galaxies, the positive contribution of the logarithmic term enables the quantum gravitational term to provide stable additional gravity, which is equivalent to the gravitational effect of the traditional dark matter halo but without the need to hypothesize unknown particles:
Physical nature: The statistical average effect of non-local entanglement of quantum vortices at the galactic scale, transmitted as macroscopic gravity enhancement through AdS/CFT duality.
Advantage: All parameters are correlatable with observations (e.g., corresponds to stellar luminosity and gas distribution), avoiding the theoretical flaw of dark matter being “undetectable”.
4.4. Universal Logarithmic Asymptotics of Dark-Matter Halo Models
A wide variety of dark-matter halo profiles [
11,
12,
13] have been proposed to explain the flat rotation curves of galaxies, including cuspy profiles derived from N-body simulations and phenomenological cored profiles motivated by observations. Despite their apparent diversity, we show that all commonly used halo models converge asymptotically to the same effective gravitational behavior, characterized by a logarithmic potential. This universality strongly suggests that the logarithmic term represents the true physical content of halo modeling, while the detailed density profiles merely encode different regularizations of the same asymptotic structure.
4.4.1. General Condition for Flat Rotation Curves
For a test particle on a circular orbit, the centripetal acceleration satisfies , where A flat rotation curve: , implies ,
However, no realistic halo model maintains at arbitrarily large radii, as this would lead to divergent total mass. Consequently, all viable models steepen to , which leads to , .
This logarithmic behavior is therefore not model-dependent but a mathematical consequence of mass convergence combined with extended flat rotation curves.
4.4.2. Cuspy Halo Models: NFW and Einasto
4.4.2.1. NFW Profile
The NFW profile: , satisfies .
Integrating:
, and thus .
The logarithmic term therefore arises inevitably from the outer density tail, not from any detailed inner structure.
4.4.2.2. Einasto Profile
The Einasto profile: , ,
admits the expansion:
.
Hence: , which again steepens toward an effective behavior at large radii, yielding .
The shape parameter merely controls how rapidly the logarithmic regime is approached.
4.4.3. Cored Halo Models: Burkert and Pseudo-Isothermal
Cored profiles replace the inner cusp with a constant-density core but retain the same outer asymptotics.
For example, the Burkert profile: , satisfies ,
leading again to
, .
Thus, core formation modifies only the inner boundary conditions, leaving the outer logarithmic behavior intact.
4.4.4. Self-Interacting and Wave Dark Matter
Self-interacting dark matter (SIDM) and fuzzy/wave dark matter (FDM) models generate cores through microphysical mechanisms (collisions or quantum pressure). Nevertheless, in all cases the outer halo relaxes to an NFW-like tail, , ensuring .
Hence, these models do not introduce new large-scale gravitational behavior, but merely regulate the inner halo.
4.4.5. Universality of the Logarithmic Potential
Since , the asymptotic form corresponds to an effective potential: up to slowly varying prefactors.
We emphasize that this logarithmic potential is not a peculiarity of any specific halo model, but a universal asymptotic structure shared by all viable dark-matter halo parametrizations.
4.4.6. Comparison with the Logarithmic Term in the Present Model
In the present framework, the additional gravitational contribution is:
which yields directly:
Thus, the logarithmic potential emerges as a primary theoretical prediction, rather than as a secondary consequence of an assumed halo density distribution.
All standard halo models may therefore be interpreted as effective parametrizations of this logarithmic term, with their apparent diversity reflecting different regularizations of the same asymptotic behavior.
5. Cross-Scale Consistency and Theoretical Advantages
5.1. Consistency of Dual-Scale Mechanisms
Although the effects of the logarithmic term at the black hole and galactic scales seem opposite, they originate from the same physical nature:
Scale correlation: Both the repulsive potential at the black hole scale and the additional gravity at the galactic scale are macroscopic manifestations of the topological structure and non-local entanglement of quantum vortices, with only changes in the sign and magnitude of caused by distance .
Parameter unification: Core parameters such as the -factor and have consistent definitions across dual scales; only dynamic adjustments of and are made to adapt to scale differences, with no additional hypotheses.
5.2. Comparative Advantages over Traditional Theories
| Comparison Dimension |
This Theory (Quantum Gravitational Correction with Logarithmic Term) |
Traditional Theories (Kerr Black Hole + Dark Matter) |
| Singularity problem |
Physically resolved, satisfying information conservation |
Unresolved, with curvature divergence |
| Free parameters |
None (black holes) / 4 physical parameters (galaxies) |
Black holes require fitting of spin and inclination; galaxies rely on dark matter distribution hypotheses |
| Cross-scale unification |
Covers microscopic to macroscopic scales under a single framework |
Black hole and galactic dynamics are fragmented |
| Observational verification |
Double verification via black hole shadows and galactic rotation curves |
Dark matter particles not directly detected; black hole spin lacks independent verification |
| Physical picture |
Clear image of quantum vortices + AdS/CFT duality |
Dark matter nature unknown; Kerr black hole lacks microscopic physical support |
6. Conclusions and Outlook
Through a unified non-perturbative quantum gravity framework, this paper reveals the cross-scale universality of the quantum gravitational correction term with a logarithmic term. Its minimalist mathematical form not only resolves singularities and addresses the information paradox through a repulsive potential at the black hole core but also maintains the flatness of galactic rotation curves via additional gravity in the galactic periphery, eliminating the need for traditional hypotheses such as dark matter and black hole spin fitting. Validated by both black hole shadow observations (EHT) and rotation curve measurements of multiple galaxies, the framework realizes a unified description of gravity from the microscopic to the macroscopic scale, providing observable and reproducible empirical support for quantum gravity theory.
Future research can be further expanded in three directions: 1) Apply the framework to more extreme scales such as black hole thermodynamics, radio bursts, and galaxy clusters to verify the universal boundary of the logarithmic term; 2) Explore solutions to cosmological puzzles such as dark energy and Hubble tension based on the properties of the logarithmic term; 3) Directly verify the quantum entanglement effect corresponding to the logarithmic term through laboratory simulations (e.g., superfluid helium quantum vortex systems), providing a more solid microscopic experimental foundation for the theory.
This study suggests that gravitational behavior in the universe, from black holes to galaxies, may be governed by the same quantum gravitational mechanism, with the logarithmic term serving as the core carrier of this mechanism. Its simplicity and powerful cross-scale adaptability open up a new path for the unification of astrophysics and gravitational theory.
Competing Interests
The author declares no competing interests.
Author Contributions
H.H. conceived the research, developed the theoretical framework, derived the key formulas, performed the data fitting and observational verification, and wrote the manuscript.
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