Accreting White Dwarfs: An Unreview
Simone Scaringi1,2, Christian Knigge3, Domitilla de Martino2
1Centre for Extragalactic Astronomy, Department of Physics, Durham University, South Road, Durham, DH1 3LE UK.
Space Science Reviews
|March 27, 2026
Summary
Accreting white dwarfs (AWDs) offer insights into accretion physics. This review highlights unresolved questions about viscosity, outflows, and magnetic field interactions in AWDs to guide future research.
Area of Science:
- * Astrophysics
- * Computational Physics
- * Stellar Evolution
Background:
- * Accreting white dwarfs (AWDs) are crucial for studying disk accretion.
- * Their characteristics allow probing fundamental physics of angular momentum transport, outflow generation, and disk-magnetosphere coupling.
- * Despite extensive research, key aspects of accretion in AWDs remain poorly understood.
Purpose of the Study:
- * To identify and discuss critical unresolved questions in accreting white dwarf research.
- * To stimulate new observational, numerical, and theoretical investigations into accretion physics.
- * To advance the understanding of accretion processes across various astrophysical scales.
Main Methods:
- * This work is an "unreview" focusing on unknown aspects of accretion physics.
- * It synthesizes current knowledge gaps and proposes avenues for future research.
- * It does not present new experimental data but rather highlights theoretical and observational challenges.
Main Results:
- * Key open questions identified include the drivers of viscosity in neutral disks.
- * The mechanisms for launching powerful winds and their feedback are unclear.
- * The origins of persistent retrograde precession and magnetic bursts in AWDs require further investigation.
Conclusions:
- * Significant gaps exist in our understanding of accretion physics in AWDs.
- * Addressing these unknowns requires integrated observational, numerical, and theoretical approaches.
- * Advancing AWD research will enhance our comprehension of accretion from stellar remnants to black holes.
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