Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

B Is light a wave or particle?

  1. Jul 26, 2017 #1
    I heart from my friend that light is both wave and particle but i dont know that is true or not.
    So can you guy tell me what light actually is?
    And how light travel from the source and then to our eye?
  2. jcsd
  3. Jul 26, 2017 #2


    Staff: Mentor

    If you are interested in learning physics, it's better to find a good textbook.

    It's a common pop science description, but it's not really accurate.

    No, but we can point you in the direction of scientific models of light that make good predictions. The best model we currently have is quantum electrodynamics, which is a quantum field theory; in this theory, light is modeled as a spin-1 quantum field. That doesn't really correspond to anything in our everyday experience; that's a key reason why pop science descriptions can't really teach you the physics.

    This is much too broad a question for a PF thread. I would advise taking some time to learn the basics of quantum mechanics from a textbook.

    Can you describe a much more specific scenario that raises a particular issue you're concerned about?
  4. Jul 26, 2017 #3


    User Avatar
    Science Advisor
    Homework Helper
    Gold Member
    2017 Award

    Light can behave as both a wave and a particle. This is not something that can be answered in a few sentences, though. I would start with this video from Khan Academy
  5. Jul 26, 2017 #4


    Staff: Mentor

    It's neither, but to allow lay persons to get a bit of a grip on QM lay texts often say it is. QM is a very hard subject to understand properly at the beginner level so liberties are taken. Here we do not take liberties but tell you the truth form the start. So I will repeat it - its neither particle or wave - technically it's excitation's in an underlying quantum electromagnetic field that permeates all of space. At the beginner level this very cheap book presents this correct view, although even it has issues, but nothing a beginner should worry about:

    You need a background beyond beginner level to understand the proper theory.

    Now this is beyond B level and you will not understand it, but hopefullly you will glean a bit of the truth from it. Dont worrry if you don't though, I post it just in the hope you will get something from it:

  6. Jul 27, 2017 #5


    User Avatar
    Science Advisor

    Isn't there a FAQ entry that answers this question?
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted