Methods & References

Technical spine for calculators and demos (CST timing, tunnel routing, curvature-invariant diagnostics, event-horizon planner). Version: v1.1

Assumptions

Equations

Reachability in an expanding universe

Under constant-H approximation the comoving separation obeys dD/dt = -v_eff + H0 · D. A target is reachable in this model iff v_eff > H0 · D0.

Time (given speed)
t = (1/H0) · ln( v_eff / (v_eff − H0·D0) )
Speed (given time T)
v_eff = (H0·D0) / (1 − e^{−H0·T})

Cosmology from redshift

Comoving distance from redshift z: D_C = (c/H0) \u22c5 \int_0^z \frac{dz'}{E(z')}, with E(z) = \u221a[\,\Omega_m(1+z)^3 + \Omega_k(1+z)^2 + \Omega_\Lambda\,]. We integrate numerically (Simpson).[C1]

Navigation and matching

Curvature invariants as a diagnostic

We use scalar curvature invariants—coordinate-independent scalars built from the Riemann tensor—to visualize and compare warp-drive spacetimes without coordinate distortions. Following recent curvature-invariant studies, we compute and plot these invariants for the Alcubierre and Natário metrics at constant velocity, varying velocity, skin depth, and radius to see how the shape function sculpts the bubble and exposes a “safe harbor.” For constant-velocity Natário, the invariant plots do not show a wake; that feature appears in the accelerating Natário case, highlighting how acceleration changes curvature structure. [W2, A3]

Why invariants? Invariants are independent of coordinate choices, so maps generated from them avoid coordinate mapping artifacts and give a cleaner view of geometric features (ridges, wakes, low-curvature pockets).

Positive-energy solitons as candidate sources

Separately, Lentz constructs a class of hyper-fast solitons in Einstein–Maxwell–plasma theory that can move effectively superluminal while being sourced by positive energy densities from classical EM fields and conducting plasma. We treat such solitons as candidate stress-energy patterns that could, in principle, supply curvature profiles similar to those we diagnose via invariants (energy scales and stability remain open). [P2]

How we combine them (workflow)

  1. Select a metric/soliton family: Alcubierre/Natário shape functions or Lentz-type solitons (metric-agnostic front-end).
  2. Evaluate curvature invariants: locate low-curvature “safe harbor,” identify wakes/ridges, and tune bubble geometry and skin depth.
  3. Map geometry to drive inputs: translate target curvature into field/shield set-points (EM/plasma distributions), constrained by CST timing and safety envelopes.
  4. Check cosmology: for intergalactic targets, compare required v_eff to H0 · D0 (or compute D0 from redshift) to assess reachability/time-to-target.
  5. Export & reproduce: every calculator exposes Download Inputs/Load Inputs (JSON); advanced users can feed these into external toolchains.

Notes & cautions

Reproducibility

Inputs/outputs: calculators expose Download Inputs / Load Inputs (JSON) for peer verification.

Parameters include version tags, H0, Ω, redshift/D0, mode (speed or time), and either veff or T.

External tools: JSON is designed to be adapter-friendly for third-party analyzers (e.g., warp-metric workbenches) when available.

A changelog appears on each calculator page.

Selected References

A full bibliographic PDF is available on the home page as “Reference Compendium (PDF)”.