quantum field theory

Thân thiện

A student reads a textbook about quantum field theory.

Definition

Noun: - A branch of quantum physics: Quantum field theory is the theoretical framework that combines quantum mechanics with classical field theory. It is used to construct physical models of subatomic particles and their interactions, treating particles as excited states of underlying physical fields.

Usage

• Quantum field theory provides the foundation for the Standard Model of particle physics.
• Understanding quantum electrodynamics requires a grasp of quantum field theory.
• Researchers use quantum field theory to calculate the probabilities of particle interactions.

Advanced Usage

• Perturbative quantum field theory: A common approach where calculations are performed as a series of approximations (perturbations) around a known solution.
  • Many predictions in particle physics are made using perturbative quantum field theory.
• Non-perturbative aspects: Refers to phenomena in quantum field theory that cannot be described by perturbation series, such as confinement in quantum chromodynamics.
  • Lattice gauge theory is a computational method used to study non-perturbative aspects of quantum field theory.

Variants and Related Words

• Quantum Electrodynamics (QED): The quantum field theory that describes how light and matter interact.
• Quantum Chromodynamics (QCD): The quantum field theory that describes the strong interaction between quarks and gluons.
• Gauge theory: A type of quantum field theory where the Lagrangian is invariant under certain local transformations (gauge symmetries).

Synonyms

• Relativistic quantum field theory (when emphasizing compatibility with special relativity)
• Field-theoretic approach

Related Phrases

• Second quantization: A formalism in quantum field theory where fields themselves are quantized.
  • The concept of particle creation and annihilation is naturally described by second quantization in quantum field theory.
• Path integral formulation: A formulation of quantum field theory using integrals over all possible field configurations.
  • The path integral formulation offers a powerful way to visualize quantum field theory calculations.

Học thuật

Noun

1. the branch of quantum physics that is concerned with the theory of fields; it was motivated by the question of how an atom radiates light as its electrons jump from excited states