Tested horizon · interior construction programme

SSZ Interior and
Global Structure

Finite horizon coefficients are repeatedly reproduced. The centre asymptotics diagnose the presently studied diagonal extrapolation, while a physical SSZ inner solution or boundary completion remains open for construction and testing.

r→0
Metric: canonical static diagonal continuation Radius: areal \(r\) Status: present extrapolation diagnosed Alternative SSZ completion: open
Reviewer scope: the present continuation has divergent curvature invariants. This identifies requirements for the next inner solution; it does not exclude a regular SSZ core, boundary geometry or different topology once explicitly derived and tested.
Definitions before conclusions

Three geometries must not be conflated

Defined

Exterior/strong static profile

The piecewise public profile supplies \(\Xi(r)\), \(D(r)\) and the static spherical metric in its declared branches.

Formal continuation

Continue the same formula to \(r\to0\)

This is the object for which the P0 invariant asymptotics are stated. It is mathematically inspectable but not thereby a physical stellar or black-hole interior.

Missing

Physical inner solution

A new metric and matter/dynamical solution with explicit matching, regularity and causal analysis has not yet been supplied.

Local statements

The Schwarzschild scale and the areal centre are different loci

At \(r=r_s\)

\[\Xi(r_s)=1-e^{-\varphi}\approx0.801711847,\qquad D(r_s)\approx0.555027709\]

Within the declared static chart, the time factor is finite and nonzero. This is the strongest secured theoretical result of the current static programme.

As \(r\to0^+\)

\[A(r)=D^2(r)\to\frac14,\qquad 4\pi r^2\to0\]

A finite temporal coefficient is only the first rung of a regularity analysis. Because \(r\) is areal radius, invariant curvature at \(r=0\) must also be checked.

Invalid inference: finite \(D(r_s)\Rightarrow\) no global horizon, no trapped surfaces, regular centre, or complete spacetime. None of those implications follows from one local coefficient.

Coordinate-independent diagnostics

Curvature of the present diagonal continuation

Ricci scalar

\[R(r)\sim\frac{3}{2r^2}\]

Diverges as \(r^{-2}\).

Kretschmann scalar

\[K(r)=R_{\alpha\beta\gamma\delta}R^{\alpha\beta\gamma\delta}\sim\frac{9}{4r^4}\]

Diverges as \(r^{-4}\).

Ricci-tensor square

A complete certificate must publish \(R_{\mu\nu}R^{\mu\nu}\) with its exact leading coefficient and source derivation. The present portal does not invent that coefficient.

calculation required

P0 conclusion: the canonical diagonal continuation is not regular at the areal centre. Older claims of complete singularity freedom are superseded.

Completeness is a trajectory theorem

Radial and non-radial geodesics

Required calculation

\[\frac{d^2x^\mu}{d\lambda^2}+\Gamma^\mu_{\alpha\beta}\frac{dx^\alpha}{d\lambda}\frac{dx^\beta}{d\lambda}=0\]

For null curves \(\lambda\) is affine; for timelike curves proper time may parametrise the path. One must prove whether every inextendible path has unbounded parameter or reaches a genuine boundary.

Current evidence boundary

Selected numerical trajectories and conserved-quantity checks test implementations over finite domains. They do not prove radial or non-radial geodesic completeness of a maximal spacetime.

Open-interior Claim-ID
Global questions

Null congruences, trapping and maximal extension

QuestionRequired objectCurrent statusAcceptance criterion
Null expansions\(\theta_+\), \(\theta_-\) for future-directed radial null congruencesopenSign map across a declared global chart
Trapped surfacesClosed two-surfaces with both expansions negativeopenInvariant calculation, not coefficient inspection
Causal completenessAll causal curves and spacetime boundaryopenMaximal extension and boundary classification
Global hyperbolicityCauchy surfaces and causal diamondsopenProof for the completed geometry
Collapse/formationTime-dependent field equations plus matteropenWell-posed evolution producing the proposed state
Possible research directions, not established solutions

What a completion could look like

Regular material core

Introduce an interior stress-energy model with finite density/pressure invariants, solve its equations and match to the SSZ exterior.

Boundary geometry

Treat the inner limit as a genuine boundary and specify admissible causal curves, boundary data and conservation laws.

Different topology or areal map

A nonzero minimal sphere or other topology would require a new metric definition. It cannot be inferred by relabelling the current areal coordinate.

Matching requirements

Junction conditions and effective source

No thin shell

For a standard non-null matching surface, continuity of the induced metric and extrinsic curvature is required to avoid a distributional surface layer.

\[[h_{ab}]=0,\qquad[K_{ab}]=0\]

With a shell

If \([K_{ab}]\neq0\), the surface stress tensor must be calculated, interpreted and tested against energy conditions. A smooth-looking plot is insufficient.

\[S_{ab}\propto [K_{ab}]-h_{ab}[K]\]

Missing foundation: without a complete SSZ action or field equations, \(T^{\rm eff}_{\mu\nu}=G_{\mu\nu}/(8\pi G)\) is a diagnostic reconstruction, not a derived fundamental matter law.

Falsifiable completion programme

Concrete next tasks

PriorityTaskDeliverableNegative result retained
P0Independent symbolic invariant packageExact \(R\), \(R_{\mu\nu}R^{\mu\nu}\), \(K\) plus 50-digit limitsAny divergence remains public
P0Radial/null geodesic certificateAffine-parameter analysis and extension boundaryFinite affine termination
P1Candidate regular interiorMetric, source, equations, regularity and matchingNo admissible matching or energy-condition failure
P1Null-expansion map\(\theta_\pm\), trapped/marginal surfacesTrapped region found
P2Dynamical formationWell-posed collapse/evolution modelInstability or non-formation