Quantum field theory unifies classical mechanics, special relativity, and quantum mechanics into a single theoretical framework describing particles as excitations (ripples) of underlying fields, with quantization—the postulate that action is discretized in units related to Planck's constant—governing how classical quantities such as energy and momentum become quantized (e.g., Planck's E = nhν rule for harmonic oscillators and Einstein's photon relation E = hν for light). Renormalization is the complementary mathematical procedure that resolves the divergences and infinities arising in quantum field theoretic calculations by replacing bare, postulated parameters (mass, charge) with finite, experimentally observed values, enabling the theory to yield physically meaningful predictions despite fields having infinite degrees of freedom.
Quantum field theory unifies classical mechanics, special relativity, and quantum mechanics into a single theoretical framework describing particles as excitations (ripples) of underlying fields, wit…