Coherent states of neutrinos in rotating matter

arXiv:2610.19078 · hep-th, astro-ph.HE, hep-ph · Submitted 2026-10-13 · Read on arXiv

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Introduction to the show: ident: Astrophysics Radio. Generated commentary on the latest astrophysics papers.

Vera: I'm Vera.

Jocelyn: And I'm Jocelyn, here with Subrahmanyan.

Vera: Today's paper: "Coherent states of neutrinos in rotating matter".

Jocelyn: The gist: The study constructs generalized coherent states for neutrinos electroweakly interacting with rotating matter,

Vera: First, who's behind it and why it matters.

Paper summary: Vera: Well, to summarize what we just discussed about "Coherent states of neutrinos in rotating matter," the authors start with a standard Dirac equation for a massive neutrino in a background medium that has a potential dependent on position. They then take two specific limits: first, they look at the limit where the particles become massless and consider a particular velocity profile for that matter.

Jocelyn: After setting up this reduction, they manage to get the neutrino Hamiltonian down to the form of a harmonic oscillator. This is what allows them to find exact solutions for the Dirac equation in this simplified scenario, which is really clever.

Subrahmanyan: That reduction into a harmonic oscillator form is crucial because it's what lets them construct those creation and annihilation operators that lead to their generalized coherent states. It’s the mathematical key they use to build the states themselves, not just solve for them in isolation.

Vera: Exactly. They use those operators to build these generalized coherent states of neutrinos, and then they interpret these states by relating them back to classical physics concepts. This is where the connection between quantum math and real-world intuition comes in for us.

Jocelyn: The paper shows that when you look at the limit of slow matter rotation, these constructed coherent states actually approach plane waves. That's a key finding because it connects the quantum description to something we can easily picture as a wave propagating through space.

Subrahmanyan: And they also define this effective neutrino mass that arises specifically from the interaction between a massless neutrino and that rotating matter. That definition is what makes it relevant for cosmology or astrophysics, because you need those mass terms to calculate propagation effects over large distances.

Vera: So, in short, "Coherent states of neutrinos in rotating matter" takes a tricky problem—neutrinos in spinning media—simplifies it into an oscillator problem, builds specific quantum states from that, and shows how these states behave classically under slow rotation while defining an effective mass term.

Jocelyn: It’s a framework that lets us treat the neutrino interaction with rotating matter in a very specific way, providing those coherent states as the starting point for understanding the dynamics.

Subrahmanyan: And it sets up a pathway to see how these effects might manifest when we look at extreme environments, which is what I'm interested in next.

Vera: Right, so we’ve got the overview of the paper—it’s about finding these specific neutrino states through a mathematical reduction and showing their classical limit under slow rotation while defining an effective mass term.

Jocelyn: And that sets us up perfectly to discuss what this actually means for observable phenomena in space.

Conclusion: Vera: So, looking at the title "Coherent states of neutrinos in rotating matter" and the work by Breev and Dvornikov, what they've done is essentially mapping out a way to describe neutrino behavior when it’s interacting with spinning matter. The core contribution is showing that under slow rotation, these coherent states behave like simple plane waves.

Jocelyn: That means for a lot of our theoretical work, we can use this mathematical construction as a starting point to understand the dynamics in a way that connects directly to classical wave propagation when things aren't rotating too fast. The effective neutrino mass they define is also something concrete that we can plug into models about how neutrinos travel through dense environments.

Subrahmanyan: From a cosmological perspective, this framework helps us quantify the influence of matter rotation on neutrino propagation, even if the paper focuses on a specific interaction mechanism. The fact that they are able to define an effective mass from this interaction is what makes it useful for calculating effects in high-density systems.

Vera: It’s about taking a complex quantum problem and showing us a simpler, physically intuitive description—the plane wave limit—and giving us a calculable parameter, the effective neutrino mass, tied to the rotation.

Jocelyn: And the authors clearly show that they have defined these generalized coherent states and studied their special case where parameters are degenerate. This suggests there's a specific regime where this description is particularly useful for understanding neutrinos in rotating astrophysical objects.

Subrahmanyan: The main implication for me is how this connects structure formation or supernova physics to the properties of these neutrino states when they are embedded in rotating backgrounds, provided we can handle the non-slow rotation limits they mentioned as a caveat.

Vera: So, to wrap up on "Coherent states of neutrinos in rotating matter," it's a constructive paper that gives us a set of coherent states, shows their classical limit under slow rotation to be plane waves, and provides an effective neutrino mass definition from the interaction with rotating matter.

Jocelyn: And it points toward using these states for modeling neutrino behavior in dense astrophysical systems where rotation plays a role.

Subrahmanyan: It’s a piece of the puzzle that gives us a rigorous mathematical structure to apply when we look at neutrinos in environments like rapidly rotating neutron stars, assuming the approximations they set up hold for those scenarios.

Pushkov Institute of Terrestrial Magnetism, Ionosphere and Radiowave Propagation (IZMIRAN)

hep-th, astro-ph.HE, hep-ph

Submitted: 2026-10-13

Updated: 2026-10-13

Comments: 47 pages, 1 figure

License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/

Importance score: 67/100

The gist: The gist: The study constructs generalized coherent states for neutrinos electroweakly interacting with rotating matter, demonstrating that these states approach plane waves in the limit of slow

Key concepts

Dirac Equation in Rotating Matter: This is the fundamental equation describing how a massive neutrino moves when it interacts with matter that is also rotating. The authors simplify this complex equation by looking at specific limits, turning it into a simpler harmonic oscillator form, which makes finding solutions possible.
Generalized Coherent States: These are special quantum states for neutrinos constructed using creation and annihilation operators. They are used to describe the neutrino field in a way that connects quantum mechanics to classical physics. These states have specific properties related to how they behave in the presence of rotating matter.
Neutrino Coherent States: This is a specific type of generalized coherent state that arises when certain parameters within the system are degenerate. Studying these states helps reveal important physical properties and allows for a more detailed analysis of neutrino behavior under specific conditions.
Effective Neutrino Mass: This concept describes an apparent mass that a neutrino acquires due to its interaction with rotating matter, even if the neutrino itself is fundamentally massless. The paper calculates this effective mass for different energies, which is crucial for understanding astrophysical phenomena like those in neutron stars.

Summary

The gist: The study constructs generalized coherent states for neutrinos electroweakly interacting with rotating matter, demonstrating that these states approach plane waves in the limit of slow matter rotation and allowing for astrophysical neutrino mass calculations in rapidly rotating neutron stars.

Theoretical Framework and Methodology

The research begins by formulating the Dirac equation for a massive neutrino propagating in background matter with a coordinate dependent effective potential, which is then reduced to the harmonic oscillator form under specific limits of massless particles and matter velocity profiles The authors find exact solutions to this reduced Dirac equation and construct creation and annihilation operators to build generalized coherent states They interpret these coherent states in terms of classical physics, showing they approach plane waves when the matter rotation is slow The methodology involves using light-cone variables to formulate the Dirac equation for a neutrino interacting with moving matter

Construction of Coherent States

The generalized coherent states are built based on the solutions found in the massless case, which are derived in Sec. III The construction involves several steps:

. In Sec. IV, they are constructed based on the solutions found in Sec. III. 2610.19078> 45

The coherent states of operators Aˆ(u0) and ˆb are defined as a solution to Eq. (3.4) that satisfies the system in Eq. (4.1) The dependence on the fixed parameter λ is not indicated in the notation ψz1z2 45

The resulting coherent states are denoted as neutrino coherent states when the degenerate parameters of the system are studied 45

Spectrum and Dynamics in Rotating Matter

The spectrum of massless active neutrinos is derived by considering the reduced Hamiltonian Hˆ describing active neutrinos in a velocity field The resulting Hamiltonian Hˆ is expressed in terms of raising and lowering operators, allowing for the derivation of the spectrum 45 In the massless limit, the Hamiltonian splits into a subsystem describing active neutrinos interacting with matter, described by Hˆ, and a free subsystem corresponding to sterile neutrinos 45 The spectrum of Hˆ is given by εn(λ) = ε0 + ωan = GN2/GN − λ + √2omega − GNomega√2(2n + 1)/GN − λ, n = 0, 1, 2 > 45

Classical Interpretation and Limits

The classical interpretation of the coherent states is provided in Sec.

Improvements for AI systems

Improved system can model neutrino propagation in rotating matter by reducing it to a harmonic oscillator form, as described by Then, we consider the limit of massless particles and the specific matter velocity profile. This allows for an exact solution of the Dirac equation and construction of generalized coherent states of neutrinos.
Improved system can predict astrophysical neutrino properties by calculating the effective neutrino masses for different neutrino energies for realistic parameters of NS, applying results to astrophysical neutrinos emitted by a rotating NS in Sec. VIII.
Improved system can simulate the evolution of neutrino wave packets in moving matter with a velocity field, as described by the Ehrenfest equations (4.23), which include terms like d⟨u1⟩du0 = −2GN − λ⟨Πˆ1⟩.
Improved system can perform a classical interpretation of neutrino states by deriving the Hamiltonian symbols and Lagrangian from the reduced dynamics in the plane (u1, u2), relating them to the motion of a fictitious charged particle in a uniform magnetic field.
Improved system can characterize squeezed neutrino coherent states by analyzing their variances, showing that the eigenvalues of the matrix Σij are 1/B(1 + ρ0) and that the packet is squeezed along one principal direction and stretched along the other.