## What does off shell mean in physics?

## What does off shell mean in physics?

In physics, particularly in quantum field theory, configurations of a physical system that satisfy classical equations of motion are called “on the mass shell” or simply more often on shell; while those that do not are called “off the mass shell”, or off shell.

## Can virtual particles be on Shell?

No,virtual particles are just a tool in the mathematics describing the interaction, transferring the quantum numbers from the initial state to the final state. Their only reality is in the mathematical formula describing the model that will give the real numbers to compare with experiment.

**What does it mean for a particle to be on Shell?**

On-shell describes fields that obey the equations of motion and real particles; off-shell describes fields that don’t have to obey the equations of motion and virtual particles. On-shell are momenta with p2=m2 with the right m2 for the given field; off-shell are momenta that don’t obey the condition.

**What is Noida theorem?**

Noether’s theorem or Noether’s first theorem states that every differentiable symmetry of the action of a physical system with conservative forces has a corresponding conservation law. The theorem was proven by mathematician Emmy Noether in 1915 and published in 1918.

### Is the Higgs boson a virtual particle?

Yes there are “virtual” Higgs bosons. A virtual particle isn’t really a particle but a ripple / disturbance in a field. So a virtual electron is a ripple in the electron field. A virtual higgs is a ripple in the higgs field.

### Is a gluon a virtual particle?

On time scales shorter than its lifetime, the gluon may further split up into gluon pairs that are quickly absorbed by another gluon. And so on. In other words, gluons are virtual particles, flickering in and out of existence much like fireflies light up on a summer night.

**What is Emmy Noether’s theorem?**

Noether’s theorem proclaims that every such symmetry has an associated conservation law, and vice versa — for every conservation law, there’s an associated symmetry. Conservation of energy is tied to the fact that physics is the same today as it was yesterday.

**Why is Noether’s theorem so important?**

Noether’s theorem is important, both because of the insight it gives into conservation laws, and also as a practical calculational tool. It allows investigators to determine the conserved quantities (invariants) from the observed symmetries of a physical system.

#### What is Noether’s theorem simple?

#### Why God Particle is called God particle?

The Higgs boson is often called “the God particle” because it’s said to be what caused the “Big Bang” that created our universe many years ago.

**Do gluons have spin?**

Properties. The gluon is a vector boson, which means, like the photon, it has a spin of 1.

**What is Diemm?**

mm is a written abbreviation for millimeter or millimeters.

## What is the off shell current in my theory?

The quantity you get on doing such a variation (the latter) is called the off shell current in your theory. It does not satisfy (E^2 – p^2 = m^2) .

## What is the difference between on shell and off shell?

In physics, particularly in quantum field theory, configurations of a physical system that satisfy classical equations of motion are called on shell, and those that do not are called off shell . In quantum field theory, virtual particles are termed off shell because they do not satisfy the energy–momentum relation;

**What is the off shell current in a QFT?**

The quantity you get on doing such a variation (the latter) is called the off shell current in your theory. It does not satisfy (E^2 – p^2 = m^2) . The off shell current in a QFT can be evaluated for any configuration of fields.

**What are off-shell States in quantum mechanics?**

Generally speaking, an off-shell state is an instance of a quantum state that does not not satisfy the physical constraints of the theory. As such, physical constraints include conservation of quantities like energy, angular momentum etc. Off-shell states specifically, do not conserve energy/momentum and are thus regarded as unphysical.