What is the difference between a quantum and photon?

Click For Summary
SUMMARY

A quantum refers to a discrete unit in quantum mechanics, while a photon is specifically a quantum of electromagnetic energy. Not all quanta are photons; the term "quantum" encompasses various discrete entities in quantum systems. In quantum mechanics, energy is quantized, meaning it exists in distinct amounts, with each photon carrying energy defined by the equation \hbar \omega. The total electromagnetic energy in a system is the sum of the energies of all individual photons present.

PREREQUISITES
  • Understanding of quantum mechanics principles
  • Familiarity with electromagnetic theory
  • Knowledge of energy quantization
  • Basic grasp of the Planck constant (\hbar)
NEXT STEPS
  • Research the concept of quantization in quantum mechanics
  • Study the properties and behavior of photons
  • Explore the relationship between photons and electromagnetic waves
  • Learn about the implications of quantized energy in physical systems
USEFUL FOR

Students and professionals in physics, particularly those studying quantum mechanics and electromagnetic theory, will benefit from this discussion.

Florence.
Messages
1
Reaction score
0
I'm a little confused with quanta and photons, they seem to be used interchangeably. Could someone clear this up for me? That would appreciated :approve: Thanks!
 
Science news on Phys.org
A photon is a quanta, but not all quanta are photons.

A quantum is just a discrete "thing." We are not referring to a precise property or object, just referring to the fact that in quantum mechanics (which unfortunately for this discussion uses the word in its name) the systems are now discretized in respect to some of their characteristics as opposed to being continuous as they normally would for their classical counterparts.

A photon is a quantum of electromagnetic energy. That is, instead of allowing electromagnetic energy being a continuous value from 0 to whatnot, it now can only exist in discrete amounts called photons. Each photon has an energy of \hbar \omega. The total electromagnetic energy in a system (ignoring the whole vacuum energy stuff, not needed for this discussion and we can always renormalize it to zero) is the sum of the energies of all the photons in the system.
 

Similar threads

Graduate A living thing made of different photonic molecules?
  • · Replies 2 ·
Replies
2
Views
1K
High School The relation between photons and waves
  • · Replies 10 ·
Replies
10
Views
3K
Graduate Can the wavelength of a single photon be measured?
  • · Replies 88 ·
3
Replies
88
Views
25K
Graduate Difference between emission due to absorption and reflection
  • · Replies 1 ·
Replies
1
Views
1K
Graduate The attractive force of photons on other photons & matter
  • · Replies 5 ·
Replies
5
Views
17K
Graduate Frustrated Total Internal Reflection
  • · Replies 6 ·
Replies
6
Views
2K
High School The nature of virtual photons in quantum electrodynamics
  • · Replies 6 ·
Replies
6
Views
2K
Undergrad Could Quantum Dots Between Optic Fibers Create Photon Interference?
  • · Replies 6 ·
Replies
6
Views
2K
Graduate Can Two Laser Beams with Different Phases Interfere?
  • · Replies 10 ·
Replies
10
Views
3K
Undergrad Two-photon Stimulated Raman Transitions
  • · Replies 2 ·
Replies
2
Views
2K