Search results
Results from the WOW.Com Content Network
The quantum field (), corresponding to the particle is allowed to be either bosonic or fermionic. Crossing symmetry states that we can relate the amplitude of this process to the amplitude of a similar process with an outgoing antiparticle ϕ ¯ ( − p ) {\displaystyle {\bar {\phi }}(-p)} replacing the incoming particle ϕ ( p ) {\displaystyle ...
In theoretical physics, quantum field theory (QFT) is a theoretical framework that combines field theory and the principle of relativity with ideas behind quantum mechanics. [ 1 ] : xi QFT is used in particle physics to construct physical models of subatomic particles and in condensed matter physics to construct models of quasiparticles .
Quantum field theories are also used throughout condensed matter physics to model particle-like objects called quasiparticles. [16] In the AdS/CFT correspondence, one considers, in addition to a theory of quantum gravity, a certain kind of quantum field theory called a conformal field theory. This is a particularly symmetric and mathematically ...
This mirrors the historical evolution of quantum field theory, since the electron component ψ e (describing the electron and its antiparticle the positron) is then the original ψ field of quantum electrodynamics, which was later accompanied by ψ μ and ψ τ fields for the muon and tauon respectively (and their antiparticles).
In quantum field theory, an operator valued distribution is a free field if it satisfies some linear partial differential equations such that the corresponding case of the same linear PDEs for a classical field (i.e. not an operator) would be the Euler–Lagrange equation for some quadratic Lagrangian.
The Quantum Theory of Fields: Volume I Foundations. Cambridge University Press. ISBN 978-0-521-55001-7. Peskin, Michael; Schroeder, Daniel (1995). An Introduction to Quantum Field Theory. Perseus Books Group. ISBN 978-0-201-50397-5. Zinn-Justin, Jean (1996). Quantum Field Theory and Critical Phenomena (3rd ed.). Clarendon Press. ISBN 978-0-19 ...
In quantum physics and quantum chemistry, an avoided crossing (AC, sometimes called intended crossing, [1] non-crossing or anticrossing) is the phenomenon where two eigenvalues of a Hermitian matrix representing a quantum observable and depending on continuous real parameters cannot become equal in value ("cross") except on a manifold of dimension . [2]
In quantum field theory, scale invariance is a common and natural symmetry, because any fixed point of the renormalization group is by definition scale invariant. Conformal symmetry is stronger than scale invariance, and one needs additional assumptions [2] to argue that it should appear in nature.