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cornellPotentialVal
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IndisputableMonolith.QFT.Confinement on GitHub at line 103.
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100 True := trivial
101
102/-- Cornell potential value (for limit analysis). -/
103noncomputable def cornellPotentialVal (alpha sigma r : ℝ) : ℝ :=
104 -alpha / r + sigma * r
105
106/-- **THEOREM (Confinement at Long Distance)**: At large r, the potential grows linearly.
107 V(r) - σr = -α/r → 0 as r → ∞, so V(r) ~ σr asymptotically. -/
108theorem confinement_at_long_distance (alpha sigma : ℝ) :
109 Filter.Tendsto (fun r => cornellPotentialVal alpha sigma r - sigma * r)
110 Filter.atTop (nhds 0) := by
111 unfold cornellPotentialVal
112 simp only [add_sub_cancel_right]
113 have h : Filter.Tendsto (fun r : ℝ => alpha / r) Filter.atTop (nhds 0) := by
114 rw [show (0 : ℝ) = alpha * 0 from by ring]
115 exact Filter.Tendsto.const_mul _ tendsto_inv_atTop_zero
116 simp only [neg_div]
117 rw [show (0 : ℝ) = -0 from by ring]
118 exact Filter.Tendsto.neg h
119
120/-! ## String Picture -/
121
122/-- The QCD string: a flux tube connecting quark and antiquark.
123 Energy stored in the string = σ × length. -/
124structure QCDString where
125 /-- Length of the string. -/
126 length : ℝ
127 /-- Length is positive. -/
128 length_pos : length > 0
129 /-- Energy stored in the string. -/
130 energy : ℝ
131 /-- Energy = σ × length. -/
132 energy_eq : energy = stringTension * length
133