“…(46)For a fixed constant c ≥ 1, let us introduce the setR c := u ∈ L ∞ (0, T ; L 2 (R + , Adx)) : u 2 L ∞ (0,T ;L 2 (R + ,Adx)) ≤ cT γ 0 u 0 R + ,Adx) ,with γ 0 > 0 is to be defined later. Now, note thatu 0 (R + ,Adx) + T 3−2γ u 2p L ∞ (0,T ;L 2 (R + ,Adx)) ≤ u 0 (R + ,Adx) + T 3−2γ+γ 0 p c p u 0 2p L 2 (R + ,Adx) .To guarantee u ∈ R c , by invoking(46) we require thatu 0 R + ,Adx) + T 3−2γ+γ 0 p c p u 0 2p L 2 (R + ,Adx) ≤ cT γ 0 u 0 R + ,Adx) .Now by choosing 0 < γ 0 < 2γ−such that γ := 3 − 2γ + γ 0 p < 0, we obtain c R + ,Adx) ≤ cT −γ+γ 0 .…”