DRUMS Theory · Particle Physics · April 2026

Neutrino Flavor Changes in DRUMS

Superfluid excitations explain neutrino oscillations without ad-hoc mass terms — the cubic substrate naturally generates mixing

To Text Summary

Neutrino as Superfluid Excitation

In DRUMS, neutrinos are not pointlike fundamental particles. They are coherent excitations of the universal superfluid medium (UFluid), coupled to the cubic magnetic substrate. The wavefunction for a neutrino state is therefore a sum over flavor fields with distinct phase factors:

\[ \Psi_\nu(\mathbf{x},t) = \sum_i \psi_i(\mathbf{x},t) \, e^{i\theta_i(\mathbf{x},t)} \]

Each \(\psi_i\) corresponds to a flavor state \(\nu_e, \nu_\mu, \nu_\tau\). The phase \(\theta_i\) encodes the influence of the superfluid flow and the magnetic substrate on the propagation of that flavor component. Unlike the Standard Model, DRUMS does not assume the existence of neutrino mass eigenstates; flavor mixing arises from differential phase accumulation as the excitation moves through the UFluid.

Flavor is a property of the superfluid excitation, not an intrinsic quantum label. The cubic substrate breaks the degeneracy of the three flavor components, leading to observable oscillation without requiring massive neutrinos. DRUMS Superfluid–Substrate Coupling

Flavor Mixing via Phase Coupling

The cubic magnetic substrate couples to the three flavor components with different strengths, producing a mixing matrix. The time evolution of the flavor fields is governed by a coupled phase equation:

\[ \frac{d}{dt} \begin{pmatrix} \psi_e \\ \psi_\mu \\ \psi_\tau \end{pmatrix} = -i \begin{pmatrix} \phi_e & \kappa_{e\mu} & \kappa_{e\tau} \\ \kappa_{e\mu} & \phi_\mu & \kappa_{\mu\tau} \\ \kappa_{e\tau} & \kappa_{\mu\tau} & \phi_\tau \end{pmatrix} \begin{pmatrix} \psi_e \\ \psi_\mu \\ \psi_\tau \end{pmatrix} \]

Here \(\phi_i\) are the phase evolution rates for each flavor, determined by the local superfluid density and substrate orientation. The off-diagonal \(\kappa_{ij}\) represent substrate-mediated coupling between flavors — they are not mass terms but effective phase-mixing coefficients arising from the geometry of the cubic lattice. The matrix is manifestly Hermitian, ensuring unitary evolution of the superfluid excitation.

Oscillation Probability

For a neutrino produced in a pure flavor state \(\alpha\), the probability to be detected in flavor \(\beta\) after traveling a distance \(L\) is given by the standard two‑flavor oscillation formula, but with the phase difference \(\Delta\phi\) derived from the superfluid dispersion relation:

\[ P_{\nu_\alpha \to \nu_\beta} = \sin^2(2\theta) \, \sin^2\left( \frac{\Delta\phi \, L}{2} \right) \]

where \(\Delta\phi = \phi_2 - \phi_1\) is the difference in phase accumulation rates between the two eigenmodes of the mixing matrix. The mixing angle \(\theta\) is determined by the ratio of the off-diagonal coupling \(\kappa\) to the diagonal splitting \(\phi_2 - \phi_1\). Crucially, the oscillation length \(L_{\text{osc}} = 2\pi / \Delta\phi\) depends on the neutrino energy \(E\) because the superfluid phase velocity varies with energy:

\[ \Delta\phi(E) = \frac{\Delta m_{\text{eff}}^2}{2E} \]

This reproduces the observed energy dependence of neutrino oscillations, with \(\Delta m_{\text{eff}}^2\) now interpreted as an effective mass-squared difference arising from the superfluid's dispersion relation — not from a fundamental mass parameter.

Matter Effects

The local superfluid density \(\rho_{\text{sf}}\) modifies the phase evolution rates through an effective potential \(V_i(\rho_{\text{sf}})\):

\[ \phi_i = \phi_i^0 + V_i(\rho_{\text{sf}}) \]

In dense media such as the Sun or Earth, the superfluid density is enhanced, leading to a shift in the oscillation pattern. This explains the Mikheyev–Smirnov–Wolfenstein (MSW) effect without requiring a separate matter potential term. The superfluid response is naturally energy‑dependent, and the cubic substrate imprints a directional dependence on the effective potential — a testable prediction of the DRUMS framework.

Coherence and Decoherence

The superfluid has a finite coherence length \(\xi\) determined by the substrate lattice spacing. Over distances larger than the coherence length, the relative phase between different flavor components becomes randomized, leading to decoherence. The coherence length is given by:

\[ L_{\text{coh}} \sim \frac{2\pi}{|\nabla\theta_1 - \nabla\theta_2|} \]

where \(\nabla\theta_i\) are the gradients of the superfluid phase for each flavor eigenmode. This sets a maximum distance over which flavor oscillations can be observed. In long‑baseline experiments, the disappearance of oscillatory behaviour at large distances is a signature of the finite coherence of the UFluid medium, not of the intrinsic stability of mass eigenstates.

"Neutrino oscillations are a consequence of phase dynamics in a structured superfluid, not of non‑zero neutrino masses. The cubic substrate breaks flavor symmetry in a controlled, geometric way."

Predictions and Experimental Signatures

  • Energy dependence of mixing angles: The effective mixing angle \(\theta\) should vary with neutrino energy in a way that reflects the superfluid's dispersion relation, not a constant vacuum mixing angle.
  • Directional dependence: The cubic substrate has preferred axes. Neutrino oscillations should exhibit a small but measurable dependence on the direction of propagation relative to the substrate lattice — a signal absent in standard mass‑based oscillation models.
  • Coherence length cutoff: At distances exceeding \(L_{\text{coh}}\), the oscillation pattern should damp out completely, rather than continuing to oscillate as predicted by the plane‑wave approximation of massive neutrinos.
  • Matter–superfluid equivalence: The matter potential in the Sun should be exactly reproduced by the superfluid density profile, providing a direct mapping between astrophysical observations and the UFluid condensate.

Conclusion

Neutrino flavor changes are fully explained by DRUMS without any ad‑hoc mass terms. The oscillation phenomenon is a direct consequence of superfluid phase dynamics and the symmetry‑breaking influence of the cubic magnetic substrate. The mixing matrix emerges from the coupling between the three flavor fields and the substrate geometry; the energy dependence arises naturally from the superfluid dispersion relation; and matter effects are encoded in the local superfluid density.

This framework reframes neutrino physics as an observable probe of the UFluid and its lattice structure. It makes distinctive, falsifiable predictions — most notably a directional dependence of oscillation probabilities and a finite coherence length — that distinguish it from the Standard Model's massive‑neutrino explanation. If confirmed, DRUMS would not only explain neutrino oscillations but also provide a direct window into the superfluid substrate that underlies all of physics.