In theoretical physics, a Feynman diagram is a pictorial representation of the mathematical expressions describing the behavior and interaction of subatomic...

one-loop Feynman diagram is a connected Feynman diagram with only one cycle (unicyclic). Such a diagram can be obtained from a connected tree diagram by taking...

common Feynman diagrams. His first published diagram appeared in Physical Review in 1949. Wilczek, Frank (July 5, 2016). "How Feynman Diagrams Almost...

subatomic particles, which later became known as Feynman diagrams and is widely used. During his lifetime, Feynman became one of the best-known scientists in...

itself can be found using the Feynman diagram method.: 102–115  Feynman diagrams devoid of "loops" are called tree-level diagrams, which describe the lowest-order...

period of time, or to travel with a certain energy and momentum. In Feynman diagrams, which serve to calculate the rate of collisions in quantum field theory...

electron. These can all be seen in the adjacent diagram. As well as the visual shorthand for the actions, Feynman introduces another kind of shorthand for the...

possible, however, to modify the action, such that methods such as Feynman diagrams will be applicable by adding ghost fields which break the gauge symmetry...

particles can be described by a schematic representation known as a Feynman diagram, in which virtual particles are represented by internal lines. Virtual...

now called Feynman diagrams. Each line of a diagram represents a particle propagating either backward or forward in time. In Feynman diagrams, anti-particles...

possible histories of the system from the initial to the final state. A Feynman diagram is a graphical representation of a perturbative contribution to the...

u-channel (both spacelike channels). These channels represent different Feynman diagrams or different possible scattering events where the interaction involves...

In quantum field theory, a tadpole is a one-loop Feynman diagram with one external leg, giving a contribution to a one-point correlation function (i.e...

resulting sum is via Feynman diagrams, where each term can be evaluated using the position space Feynman rules. The series of diagrams arising from ⟨ 0 |...

the multiplicative factor corresponding to an internal photon in the Feynman diagram expansion of a QED calculation, contains a factor gμν corresponding...

conceptually simple way to describe them through the use of Feynman diagrams. In a Feynman diagram, each matter particle is represented as a straight line...

and it is called a vertex renormalization. The Feynman diagram for this is also called a “penguin diagram” due to its shape remotely resembling a penguin...

{\displaystyle e^{+}e^{-}\to 2\gamma } has a contribution from the second order Feynman diagram shown adjacent: In the initial state (at the bottom; early time) there...

two charge-carrying fields and one photon field (hence the common Feynman diagram with two arrows and one wavy line). Since photons mediate the electromagnetic...

Feynman parametrization is a technique for evaluating loop integrals which arise from Feynman diagrams with one or more loops. However, it is sometimes...

global anomaly cannot be captured by one loop or any loop perturbative Feynman diagram calculations—examples include the Witten anomaly and Wang–Wen–Witten...

Bethe–Feynman formula Feynman's algorithm Feynman–Kac formula Feynman–Kleinert Quasi-Classical Wigner method Feynman checkerboard Feynman diagram Feynman rules...

for the use of Green's function methods, and consequently the use of Feynman diagrams in the field under study. A more general idea in probability theory...

In quantum field theory, penguin diagrams are a class of Feynman diagrams which are important for understanding CP violating processes in the standard...

A diagram is a symbolic representation of information using visualization techniques. Diagrams have been used since prehistoric times on walls of caves...

evaluated perturbatively as the sum of all connected and disconnected Feynman diagrams. It is also the generating functional for correlation functions ⟨ ϕ...

aspects of a spatial geometry. A spin network is defined as a diagram like the Feynman diagram which makes a basis of connections between the elements of...

Schwinger commented on Feynman diagrams in the following way, Like the silicon chips of more recent years, the Feynman diagram was bringing computation...

derive Feynman's rules (see Feynman diagram). Here we have ca for the ghost field while ξ fixes the gauge's choice for the quantization. Feynman's rules...

virtual electron–positron pairs spontaneously, illustrated by the Feynman diagram in the adjacent figure. This creates nonlinear effects that are approximately...