Approximate laws




There are also approximate conservation laws. These are approximately true in particular situations, such as low speeds, short time scales, or certain interactions.

  • Conservation of mechanical energy
  • Conservation of rest mass
  • Conservation of baryon number (See chiral anomaly and sphaleron)
  • Conservation of lepton number (In the Standard Model)
  • Conservation of flavor (violated by the weak interaction)
  • Conservation of parity
  • Invariance under charge conjugation
  • Invariance under time reversal
  • CP symmetry, the combination of charge conjugation and parity (equivalent to time reversal if CPT holds)

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