What physical property of a White Dwarf is responsible for packing thermal energy into a small volume?

Answer

Extreme density

A white dwarf packs the mass of a star into the size of the Earth, resulting in incredibly high density and energy concentration.

What physical property of a White Dwarf is responsible for packing thermal energy into a small volume?
astronomytemperaturestarsstellar evolutionwhite dwarfblue giantstar temperature