Newtonian Model Developed for Rotating White Dwarfs with Relativistic Comparison
Astrophysicists have constructed a simplified one-dimensional Newtonian framework to model how uniform rotation affects the structure and mass of white dwarf stars. The approach represents centrifugal effects as an effective anisotropic pressure term, allowing rotation frequency to remain explicit while keeping the equations tractable. The work provides a transparent reference model for future, more complex axisymmetric and relativistic white dwarf calculations.
A team of researchers has developed a one-dimensional Newtonian reduction for uniformly rotating cold white dwarfs, encoding the angle-averaged centrifugal contribution as an effective anisotropic term derived from the stationary Euler equation. Using the Chandrasekhar degenerate-electron equation of state, they computed stellar structure sequences across a wide range of central densities (10⁶ to 10¹¹ g/cm³) and rotation proxies up to 35% of the local Keplerian frequency. Results show monotonic increases in both mass and radius with increasing rotation rate, with mass shifts reaching the percent level at the highest rotation proxies considered. The model's validity was assessed through sub-Keplerian diagnostics and a bulk-interior anisotropy measure, and its outputs were cross-checked against a quasi-two-dimensional reconstruction and a static Tolman–Oppenheimer–Volkoff reference sequence. These comparisons confirm the reduced model is reliable for trend-level surveys in the slow-rotation regime, though both rotational and static relativistic corrections can each become percent-level effects at high central densities. The paper, now in a substantially revised second version, is intended as a controlled Newtonian benchmark to guide and calibrate more sophisticated future models.
What's missing
The study is a preprint posted to arXiv and has not yet undergone formal peer review. The model is explicitly limited to the slow-rotation regime and uniform rotation; differential rotation and full general-relativistic treatments are deferred to future work.
What different sources said
- arXiv astro-phCenter
Rotation-Induced Effective Anisotropy in White Dwarfs as a Newtonian Benchmark with Relativistic Scale Assessment
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