Newtonian Model Developed for Rotating White Dwarfs with Relativistic Comparison
Researchers developed a simplified one-dimensional Newtonian model to describe uniformly rotating cold white dwarfs by representing rotational effects as an effective anisotropic term. The model was tested across a range of central densities and rotation rates, with results compared against relativistic calculations. This work provides a computational benchmark for studying rotating white dwarfs and understanding how rotation affects their mass and radius.
A new theoretical framework has been developed to model uniformly rotating white dwarfs using Newtonian mechanics with an effective anisotropic correction term that captures angle-averaged centrifugal support. The researchers computed sequences of white dwarf models across central densities from 10^6 to 10^11 g/cm³ and rotation rates up to 35% of the Keplerian limit, finding monotonic increases in mass and radius with rotation rate. The model was validated through comparison with quasi-two-dimensional reconstructions and relativistic Tolman-Oppenheimer-Volkoff reference sequences. Results indicate the reduced Newtonian model remains accurate for slow-rotation regimes but shows percent-level deviations at high central densities where relativistic effects become significant. The work establishes a transparent computational benchmark suitable for controlled surveys and provides a foundation for future axisymmetric and relativistic rotating white-dwarf calculations.
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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