How fast is the universe expanding? And why is that expansion accelerating? Efforts to understand these questions rely critically on one particular type of supernova.
https://www.quantamagazine.org/what-lights-the-universes-standard-candles-20230208/
@QuantaMagazine I find this very confusing—in particular, the idea of a #HyperVelocityWhiteDwarf released when its partner explodes.
If two masses are orbiting a common centre, and one of them turns into a dust cloud, how does that allow the other to fly off? The #supernova remnant still has mass.
@QuantaMagazine Sure, imagining the system as a pair of classical centres of mass orbiting their barycentre is an oversimplification.
Some mass is lost to energy. The remnant behaves differently in the interstellar medium than the predecessor white dwarf. Maybe some general relativistic difference with the different layout.
But “If there are two white dwarfs rotating around each other, and one explodes as a supernova, nothing will be left to hold onto the other” can’t be right?
Quanta Magazine
poratlu