What is a Photon? - Mass, Momentum, Speed & Wavelength

  • Thread starter Thread starter smatik
  • Start date Start date
  • Tags Tags
    Photon
smatik
Messages
14
Reaction score
1
What is a photon?
Does it have mass?(if no then why it has momentum)
it travels with speed of light?
Has it some wavelength associated with it,that can be calculated by De Broglie wave equation?
 
Physics news on Phys.org
https://www.physicsforums.com/blog.php?b=3588
 
Last edited by a moderator:
A photon is a packet of Electromagnetic Energy. Quantized light energy.

A photon doesn't have mass but it has energy which is why it has momentum. E=pc.

It travels at the speed of light because it IS light. Photons are the particle aspect of light. Light does have a measurable wavelength obviously, hence the EM spectrum. To calculate its de broglie wavelength calculate λ=h/p, h is planks constant, p is momentum.
 

Thread 'Schrödinger equation and classical wave equation'

Not an expert in QM. AFAIK, Schrödinger's equation is quite different from the classical wave equation. The former is an equation for the dynamics of the state of a (quantum?) system, the latter is an equation for the dynamics of a (classical) degree of freedom. As a matter of fact, Schrödinger's equation is first order in time derivatives, while the classical wave equation is second order. But, AFAIK, Schrödinger's equation is a wave equation; only its interpretation makes it non-classical...
View full post »

Thread 'Quantum Entanglement is a Kinematic Fact, not a Dynamical Effect'

Insights auto threads is broken atm, so I'm manually creating these for new Insight articles. Towards the end of the first lecture for the Qiskit Global Summer School 2025, Foundations of Quantum Mechanics, Olivia Lanes (Global Lead, Content and Education IBM) stated... Source: https://www.physicsforums.com/insights/quantum-entanglement-is-a-kinematic-fact-not-a-dynamical-effect/ by @RUTA
View full post »

Thread 'Is Maxwell's electromagnetism an effective (field) theory?'

Is it possible, and fruitful, to use certain conceptual and technical tools from effective field theory (coarse-graining/integrating-out, power-counting, matching, RG) to think about the relationship between the fundamental (quantum) and the emergent (classical), both to account for the quasi-autonomy of the classical level and to quantify residual quantum corrections? By “emergent,” I mean the following: after integrating out fast/irrelevant quantum degrees of freedom (high-energy modes...
View full post »

Similar threads

B Are electromagnetic wavelength and quantum wavelength the same thing?
Replies
5
Views
1K
I Do atoms recoil when emitting a photon?
Replies
38
Views
6K
B Does Wavelength Affect Uncertainty in Macroscopic Objects?
Replies
11
Views
2K
A Coleman: "Spin is a concept that applies only to particles with mass"
Replies
11
Views
1K
I The Delayed Choice experiment: Is Photon speed important?
Replies
15
Views
1K
I Young's slit experiment with single photons
2
Replies
81
Views
7K
A Upper bound for wavelength of a photon inside an infinite square well
Replies
2
Views
1K
B Virtual photons as force carriers
Replies
29
Views
3K
I How can the photon wave function be described?
Replies
27
Views
3K
B How to determine the wavefunction of photons?
Replies
4
Views
1K

Hot Threads

Recent Insights

Back
Top