[CharlesWayneCT]

Maybe you can explain what it is about physics that necessitates an old earth?

[DevNet]

Radioactive decay and the resulting extra heat produced by accelerated decay.

[PapaBear3625]

Maybe you can explain what it is about physics that necessitates an old earth?

Oh, little things like geology, fossils arranged in neat layers where you never find modern mammals or humans mixed with dinosaurs, stuff like that.

As far as astronomy is concerned, the idea that things are billions of light years away implying that the universe is older than 6,000 years is a start.

[WondrousCreation]

Maybe you can explain what it is about physics that necessitates an old earth?

You won't get a cogent answer. The only thing about physics that necessitates an old earth is the devotion of the physics community to the Temple of Darwin.

Physics has been contaminated with evolutionary nonsense since after Maxwell's time.