`BookProof.LorentzOrthochronous.orthochronous_mul` {a b : Matrix (Fin 4) (Fin 4) ℝ} (ha : IsLorentz a) (hb : IsLorentz b) (h0a : 0 < a 0 0) (h0b : 0 < b 0 0) : 0 < (a * b) 0 0

Initializing...

`BookProof.LorentzOrthochronous.orthochronous_mul` {a b : Matrix (Fin 4) (Fin 4) ℝ} (ha : IsLorentz a) (hb : IsLorentz b) (h0a : 0 < a 0 0) (h0b : 0 < b 0 0) : 0 < (a * b) 0 0 · Prove2Me