Bosonization of 1D interacting fermions: holons and spinons travel at different speeds
In 1D, interactions destroy Fermi liquid behavior. Tomonaga-Luttinger theory (bosonization) maps interacting fermions to free bosons: charge (holons) and spin (spinons) decouple with velocities v_c ≠ v_s. The Luttinger parameter K (K<1: repulsive, K=1: free, K>1: attractive) controls power-law correlations G(x,τ) ~ (x²+v²τ²)^{−(K+K⁻¹)/4}. Observe the wavepacket literally splitting into two upon injection.