Strong magnetic fields may allow dead stars known as white dwarfs to grow heavier than physicists have long believed possible, according to new simulations of magnetized white dwarfs reported by ScienceDaily. The findings challenge a limit that has shaped astronomers' understanding of stellar remnants for nearly a century.
Classic theory holds that a white dwarf cannot stably exceed about 1.4 times the mass of the Sun, the threshold known as the Chandrasekhar limit. Beyond that point, the star's own gravity overwhelms the electron pressure that holds it up. The new work suggests that a powerful magnetic field changes this balance, pushing the maximum mass considerably higher, to roughly 2.4 solar masses.
The implications could extend beyond the stars themselves. Astronomers have struggled to explain a class of supernovae that are unusually bright, and the researchers say the heavier magnetized white dwarfs described in the simulations may offer a possible explanation. If confirmed, the idea would give scientists a new way to connect the internal physics of these stars with some of the most energetic explosions in the universe.
The results come from computer models rather than direct observation, so they remain a theoretical proposal that will need testing against real stellar data before they are widely accepted.