'Off-shell' particle in an external field....

In summary, a real, observable particle is said to be 'off-shell' in an external field because the mass shell constraints cease to have meaning in this case. This means that the standard asymptotic relation $p^2=m^2$ is not satisfied, indicating that the field may influence the energy of the particle.
  • #1
asimov42
377
4
TL;DR Summary
Questioning why particles are said to be 'off-shell' in an external field...
Silly question but could someone explain why a real, 'observable' particle is said to be 'off-shell' in an external field? @A. Neumaier 's excellent FAQ notes that the mass shell constraints ceases to have meaning in this case. I'm just not fully clear on why (probably obvious) given that energy conservation still holds.
 
Physics news on Phys.org
  • #2
Or is the use of 'off shell' in this case simply to indicate that the field may influence the energy of the particle?
 
  • #3
asimov42 said:
could someone explain why a real, 'observable' particle is said to be 'off-shell' in an external field?
asimov42 said:
Or is the use of 'off shell' in this case simply to indicate that the field may influence the energy of the particle?
Off shell just means that the standard asymptotic (or free field) relation $p^2=m^2$ (in units where $c=1$), which defines the on shell condition, is not satisfied.
 
  • #4

FAQ: 'Off-shell' particle in an external field....

What is an 'off-shell' particle?

An 'off-shell' particle is a term used in particle physics to describe a particle that does not satisfy the equations of motion for a free particle. This means that the particle is not moving in a way that is consistent with its mass and energy.

How does an external field affect an 'off-shell' particle?

An external field can cause an 'off-shell' particle to deviate from its expected behavior. This can be due to interactions with other particles or the presence of a strong electromagnetic or gravitational field.

What are the implications of studying 'off-shell' particles?

Studying 'off-shell' particles can provide valuable insights into the underlying physics of particle interactions. It can also help us better understand the effects of external fields on particle behavior and potentially lead to new discoveries.

How do scientists detect 'off-shell' particles?

Scientists use sophisticated detectors, such as particle accelerators, to study 'off-shell' particles. These detectors can measure the properties of particles, such as their mass and energy, and track their movements in an external field.

What are some real-world applications of understanding 'off-shell' particles?

Understanding 'off-shell' particles is crucial for many areas of modern technology, such as medical imaging and nuclear energy. It also has implications for fundamental physics research, including the search for new particles and the development of new theories to explain the behavior of matter and energy.

Similar threads

I The claymath 4-d QFT problem and virtual particles (as an example)
2
Replies
36
Views
1K
I Are All Photons Truly Virtual?
Replies
6
Views
1K
I On-shell virtual particles and 'physical' Hilbert spaces....
Replies
7
Views
2K
A Multiparticle Relativistic Quantum Mechanics in an external potential
Replies
22
Views
2K
I Meaning of the word 'particle'
Replies
11
Views
416
A Observable particles as asymptotic states....
2
Replies
47
Views
4K
A Symmetries of particle interacting with external fields (Ballentine)
Replies
5
Views
1K
I "Wave-particle duality" and double-slit experiment
2
Replies
36
Views
4K
I Is a Particle Simply the Manifested Kinetic Energy of Its Quantum Field?
Replies
2
Views
1K
A Quantum Field theory vs. many-body Quantum Mechanics
2
Replies
36
Views
4K

Hot Threads

Recent Insights

Back
Top