## What is a Chern Simons term?

Chern–Simons theory is an exercise in the simplicity, beauty, and weirdness of topology. It is an archetypical example of a topological field theory, a quantum field theory where the physical observables are topological invariants of the spacetime in which the theory lives.

**Is Chern Simons theory a CFT?**

Chern-Simons Gauge Theory and the AdS(3)/CFT(2) Correspondence. The bulk partition function of pure Chern-Simons theory on a three-manifold is a state in the space of conformal blocks of the dual boundary RCFT, and therefore transforms non-trivially under the boundary modular group.

### What do you mean by gauge transformation?

A gauge transformation can be broadly defined as any formal, systematic transformation of the potentials that leaves the fields invariant (although in quantum theory it can be perhaps a bit more subtle than that because of the additional degree of freedom represented by the quantum phase).

**What is Lorentz and Coulomb gauge?**

Lorentz gauge and Coulomb gauge are two concepts that are important in quantum chemistry. Lorentz gauge is a partial gauge fixing of the electromagnetic vector potential while Coulomb gauge is a type of gauge that is expressed in terms of instantaneous values of the fields and densities.

## What is the difference between Lorentz gauge and Coulomb gauge?

**What is importance of Lorentz gauge?**

In electromagnetism, the Lorenz gauge condition or Lorenz gauge, for Ludvig Lorenz, is a partial gauge fixing of the electromagnetic vector potential by requiring. the equation of a massless scalar field).

### Why is it called gauge theory?

Later Hermann Weyl, inspired by success in Einstein’s general relativity, conjectured (incorrectly, as it turned out) in 1919 that invariance under the change of scale or “gauge” (a term inspired by the various track gauges of railroads) might also be a local symmetry of electromagnetism.

**What is quantum gauge theory?**

gauge theory, class of quantum field theory, a mathematical theory involving both quantum mechanics and Einstein’s special theory of relativity that is commonly used to describe subatomic particles and their associated wave fields.

## What is the significance of Lorentz gauge?

**Why is Lorentz transformation important?**

Required to describe high-speed phenomena approaching the speed of light, Lorentz transformations formally express the relativity concepts that space and time are not absolute; that length, time, and mass depend on the relative motion of the observer; and that the speed of light in a vacuum is constant and independent …

### What is the difference between Coulomb and Lorentz gauge?

Lorentz gauge is a partial gauge fixing of the electromagnetic vector potential while Coulomb gauge is a type of gauge that is expressed in terms of instantaneous values of the fields and densities.

**What is Lorentz gauge transformation?**

As Lorentz transformations act on space-time coordinates, gauge transformations are applied to the gauge field. Placing these two transformations on the same ground means that all quantized field like spin-1/2 and spin-3/2 spinors are functions not only of the coordinates but also of the gauge field components.

## What is gauge theory used for?

**What is quantum field theory in physics?**

Definition of quantum field theory : a theory in physics: the interaction of two separate physical systems (such as particles) is attributed to a field that extends from one to the other and is manifested in a particle exchange between the two systems.

### What is difference between Galilean transformation and Lorentz transformation?

Lorentz transformations are valid for any speed whereas Galilean transformations are not. According to Galilean transformations time is universal and independent of the observer but according to Lorentz transformations time is relative.

**Why Coulomb gauge is called radiation gauge?**

Because of this, the Coulomb gauge is said to be a complete gauge, in contrast to gauges where some gauge arbitrariness remains, like the Lorenz gauge below. In regions far from electric charge the scalar potential becomes zero. This is known as the radiation gauge.

## What is the level of the Chern–Simons theory?

The action S of Chern–Simons theory is proportional to the integral of the Chern–Simons 3-form. The constant k is called the level of the theory.

**What is the purpose of Chern-Simons papers?**

They contain introductory material to the general subject of Chern-Simons theory. They are meant to be elementary and pedagogical. ************* THESE NOTES ARE STILL IN PREPARATION. CONSTRUCTIVE COMMENTS ARE VERY WELCOME. (In par- ticular, I have not been systematic about trying to include references.

### What is the action integral of the Chern–Simons form?

The action integral ( path integral) of the field theory in physics is viewed as the Lagrangian integral of the Chern–Simons form and Wilson loop, holonomy of vector bundle on M. These explain why the Chern–Simons theory is closely related to topological field theory .

**What is Chern-Simons theory?**

Particularly, Chern–Simons theory is specified by a choice of simple Lie group G known as the gauge group of the theory and also a number referred to as the level of the theory, which is a constant that multiplies the action.