Temperature–Dependent Gravity in Magnetized White Dwarfs: A New Flow–Supported Regime Without Outflows

Recent VLT/MUSE observations reveal a persistent bow–shock structure surrounding the whitedwarf RXJ0528+2838 I lkiewicz & et al. (2026), despite the absence of an accretion disk or any detectablemass outflow. Bow–shock nebulae have previously been identified around compact binaries,most notably around the cataclysmic variable SY Cancri (Bond et al. 2024), and have been studiedmore generally in a broader astrophysical context (Sparavigna & Marazzato 2010; Ben-Jaffel et al.2013). The thermodynamic and evolutionary properties of white dwarfs that underpin the physicalinterpretation of such systems are comprehensively reviewed by Pelisoli & Williams (2025).In standard gravity this requires an unidentified energy source. We show that this structure arisesnaturally in Baryonic Temperature–Dependent Gravity (BTDG), where the effective gravitationalcoupling depends on the thermodynamic state of baryonic matter. The white dwarf constitutes a cold,compact thermodynamic sink embedded in warm interstellar gas, producing a stable gravitationalfocusing radius that coincides with the observed shock scale. This system defines a new, flow–supportedBTDG regime complementary to the rotational SPARC galaxies and the pressure–supported Cloud–9cold gas cloud.In SPARC disk galaxies, BTDG reproduces the observed baryonic Tully–Fisher relation and radialacceleration relation using a single temperature–dependent coupling. In the cold, pressure–supportedCloud–9 HI cloud, the same law correctly predicts the existence and scale of a compact gravitationalcore without collapse.