Topological modes in stellar oscillations

Abstract

Stellar oscillations can be of topological origin. We reveal this deep and so-far hidden property of stars by establishing a novel parallel between stars and topological insulators. We construct an hermitian problem to derive the expression of the stellar $\text{acoustic-buoyant}$ frequency $S$ of non-radial adiabatic pulsations. A topological analysis then connects the changes of sign of the acoustic-buoyant frequency to the existence of Lamb-like waves within the star. These topological modes cross the frequency gap and behave as gravity modes at low harmonic degree $\ell$ and as pressure modes at high $\ell$. $S$ is found to change sign at least once in the bulk of most stellar objects, making topological modes ubiquitous across the Hertzsprung-Russel diagram. Some topological modes are also expected to be trapped in regions where the internal structure varies strongly locally.

arXiv comment6 pages, 5 figures (+7 pages, 3 figures of appendices)

References in corpus (20)

• Topological Insulators
• Modules for Experiments in Stellar Astrophysics (MESA)
• Edge states and topological invariants of non-Hermitian systems
• Exceptional Topology of Non-Hermitian Systems
• Topological phases of non-Hermitian systems
• Dedalus: A Flexible Framework for Numerical Simulations with Spectral Methods
• Topological active matter
• Topological Origin of Equatorial Waves
• Theoretical amplitudes and lifetimes of non-radial solar-like oscillations in red giants
• Symmetry-protected multifold exceptional points and their topological characterization
• Oscillations of alpha UMa and other red giants
• Topological Gaseous Plasmon Polariton in Realistic Plasma
• New insights on the interior of solar-like pulsators thanks to CoRoT: the case of HD 49385
• Validity of the WKB Approximation in Calculating the Asymptotic Quasinormal Modes of Black Holes
• Topological phase in plasma physics
• Wave topology brought to the coast
• Unidirectional modes induced by nontraditional Coriolis force in stratified fluids
• Manifestation of Berry curvature in geophysical ray tracing
• Manifestation of the topological index formula in quantum waves and geophysical waves
• Dirac Operator and Spectral Geometry

Cited by in corpus (4)

• Anomalous Floquet Phases. A resonance phenomena
• Mode-Shell correspondence, a unifying phase space theory in topological physics -- Part I: Chiral number of zero-modes
• Modelling $\delta$ Scuti pulsations: A new grid of p, g, and f modes across pre-main-sequence to post-main-sequence evolution
• Mode-Shell correspondence, a unifying phase space theory in topological physics -- part II: Higher-dimensional spectral invariants