Lava-Void Cosmology: Testable Unified Fluid Theory

Lava-Void Cosmology: Testable Unified Fluid Theory

By C. Rich

Lava-Void Cosmology provides a unified relativistic viscous fluid framework with testable predictions across cosmic epochs. To integrate distinctive observational predictions into Lava-Void Cosmology while preserving the unified relativistic viscous fluid framework, the theory generates a set of falsifiable signatures arising directly from its core mechanisms: multifractal Planck-scale turbulence, density-dependent viscosity, helical chiral effects, and void-dominated late acceleration.

These predictions deviate measurably from the standard \( \Lambda \)CDM model in targeted observables, providing clear avenues for empirical distinction or refutation using near-term and upcoming instruments, including CMB-S4, LiteBIRD, Euclid, LSST, Roman, SKA, HERA, LISA, the Einstein Telescope, and pulsar timing arrays.

Unlike \( \Lambda \)CDM, which relies on separate dark components and scalar-field inflation, Lava-Void predictions emerge intrinsically from fluid dynamics across scales, offering direct smoking-gun tests while maintaining consistency with existing data.

This extension culminates the framework’s development, yielding a comprehensive unified alternative with explicit observational testability.

Key Distinctive Predictions

1. Scale-dependent non-Gaussianity from turbulent intermittency
   • Primordial perturbations exhibit mild multifractal deviations from Gaussianity, with local bispectrum
     \( f_{\rm NL} \approx 5\text{–}20 \) and running
     \( \alpha_{\rm NL} \approx 0.1\text{–}0.5 \),
     contrasting with near-zero values in \( \Lambda \)CDM.
   • Testable via Planck bispectrum residuals, CMB-S4 constraints, or LSST and Euclid galaxy bispectra.
2. Chiral primordial gravitational waves
   • Helical turbulence sources circularly polarized tensor modes with polarization fraction
     \( \mathcal{R} \approx 0.01\text{–}0.1 \),
     tensor-to-scalar ratio
     \( r \approx 10^{-3}\text{–}10^{-2} \),
     and slightly blue tilt
     \( n_t \approx +0.1 \).
   • Produces TB and EB CMB polarization correlations absent in parity-even \( \Lambda \)CDM.
   • Detectable by LiteBIRD, CMB-S4, LISA, or the Einstein Telescope.
3. Void-induced large-scale anisotropies and flows
   • A local underdense void of scale \( \sim100\text{–}200\,{\rm Mpc} \) induces dipole-modulated expansion,
     reconciling
     \( H_0 \approx 73\,{\rm km\,s^{-1}\,Mpc^{-1}} \)
     locally with global
     \( H_0 \approx 67\,{\rm km\,s^{-1}\,Mpc^{-1}} \).
   • Predicts bulk flows of
     \( \sim300\text{–}500\,{\rm km\,s^{-1}} \)
     on
     \( \sim100\,h^{-1}\,{\rm Mpc} \)
     scales.
   • Testable via DESI and Euclid peculiar velocities or kSZ measurements from CMB-S4.
4. Modified small-scale structure and power suppression
   • Density-dependent viscosity produces cored dwarf halos with
     \( r_{\rm core} \approx 0.5\text{–}2\,{\rm kpc} \),
     reduced satellite abundance, and stochastic rotation curves.
   • Predicts enhanced void fractions and outflow velocities relative to \( \Lambda \)CDM.
   • Constrainable via LSST dwarf kinematics, Euclid lensing, or Milky Way satellite surveys.
5. Enhanced patchy reionization and 21 cm signatures
   • Rapid late reionization with
     \( z_{\rm re} \approx 7.5 \),
     \( \Delta z \approx 1\text{–}2 \),
     and deeper global 21 cm absorption troughs
     (\( \sim-200 \) to \( -300\,{\rm mK} \)).
   • Enhanced patchy kSZ power on arcminute scales.
   • Observable by SKA and HERA 21 cm measurements and CMB-S4 anisotropies.

Mathematical Formulation (Selected Examples)

For chiral gravitational-wave polarization, the asymmetry in tensor power spectra is

\[
\Delta_t(k)
=
\Delta_t^R(k)
–
\Delta_t^L(k)
\propto
\langle \mathbf{v} \cdot {\omega} \rangle
\frac{H^4}{M_{\rm Pl}^4}
\left( \frac{k}{aH} \right)^{\delta_{\rm hel}}
\]

where the helicity density
\( \langle \mathbf{v} \cdot {\omega} \rangle \)
is controlled by intermittency with
\( \delta_{\rm hel} \approx 0.2\text{–}0.5 \).

The intermittency-driven primordial bispectrum is

\[
B_\zeta(k_1,k_2,k_3)
\approx
f_{\rm int}(k)
P_\zeta(k_1) P_\zeta(k_2)
+
{\rm permutations}
\]

where \( f_{\rm int}(k) \) exhibits scale dependence from multifractal exponents.

Failure to detect chiral B-modes
(\( r < 10^{-3} \) with no parity violation)
or resolution of the Hubble tension without void signatures would challenge the model.
Conversely, detection of TB or EB correlations would strongly favor Lava-Void Cosmology.

With this integration, Lava-Void Cosmology achieves unified, testable coverage across cosmological epochs and probes, offering a minimally parametrized framework ripe for observational scrutiny.

C. Rich