English
If Γ0 is nontrivial, then v(x) = ⊤ iff x = 0 for x in the division ring.
Русский
Пусть Γ0 ненулево, тогда для любой x из поля, v(x) = ⊤ тогда и только тогда, когда x = 0.
LaTeX
$$$$ v(x) = \top \iff x = 0, \quad \text{assuming } [\text{Nontrivial } \Gamma_0]. $$$$
Lean4
/-- If `v` is an additive valuation on a division ring then `v(x) = ⊤` iff `x = 0`. -/
@[simp]
theorem top_iff [Nontrivial Γ₀] (v : AddValuation K Γ₀) {x : K} : v x = (⊤ : Γ₀) ↔ x = 0 :=
v.zero_iff