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

Light is a type of matter

  1. May 31, 2009 #1
    My friend believe that light is a type of matter. He thinks that light is a matter because it can be sucked into the black hole. So, I've wondered this. Is light a type of matter, or is it just a wave. If it is a wave, how can it be sucked into the black hole. Is light effected by the gravity? How can light travels through vacuum. What is the differences between the sound wave and the light wave, apart from sound wave need medium to travel.
     
  2. jcsd
  3. May 31, 2009 #2

    DaveC426913

    User Avatar
    Gold Member

    Re: Light?

    Your friend is wrong.

    Light is energy. Energy is affected by gravity. Gravity does not suck things; what gravity does is distort space-time. Light, and all other forms of electromagnetic radiation, follows the curved paths made by distorted space-time.
     
  4. Jun 1, 2009 #3
    Re: Light?

    light would be affected even if it was a wave.
     
  5. Jun 1, 2009 #4
    Re: Light?

    even you and I behave as a wave and a particle , wave particle duality.
    not only is light affected by gravity , it creates a gravitational field of its own.
    light is energy just like "davec426913" said but light can be transformed into matter
    an electron positron pair , E=mc^2
     
    Last edited: Jun 1, 2009
  6. Jun 1, 2009 #5

    ZapperZ

    User Avatar
    Staff Emeritus
    Science Advisor
    Education Advisor
    2016 Award

    Re: Light?

    Please start by reading an entry in our FAQ thread in the General Physics forum.

    Zz.
     
  7. Jun 1, 2009 #6
    Re: Light?

    Not to argue with you Dave but does gravity distort space-time or does mass and energy distort space-time and gravity is the affect of the distortion.
     
  8. Jun 1, 2009 #7

    Dale

    Staff: Mentor

    Re: Light?

    The particles we call "matter" are fermions which obey the Pauli exclusion principle. Photons are bosons and do not obey the Pauli exclusion principle.
     
  9. Jun 1, 2009 #8

    QuantumPion

    User Avatar
    Science Advisor
    Gold Member

    Re: Light?

    I don't think this is correct. Matter is anything that has mass. There are bosons that have mass, such as the W and Z bosons (as well as composite particles such as mesons and helium-4).
     
  10. Jun 1, 2009 #9

    DaveC426913

    User Avatar
    Gold Member

    Re: Light?

    Yes. My bad. I was over-simplifying. Yours is worded better.
     
  11. Jun 1, 2009 #10

    Dale

    Staff: Mentor

    Re: Light?

    I disagree. A pair of photons travelling in opposite directions has mass, but is not matter. A container of hot gas has more mass than an otherwise identical container of cold gas, but no more matter. Etc. I would not equate matter with mass.

    The usual kind of basic definition of matter is anything that has mass and takes up space. Fermions take up space because they obey the Pauli exclusion principle. Bosons do not obey it, so they don't take up space, so they are not matter. However, you are correct that the majority of the mass of ordinary matter is due to the massive gauge bosons that mediate the strong interaction.
     
    Last edited: Jun 1, 2009
  12. Jun 1, 2009 #11
    Re: Light?

    This is a physical and metaphysical point simultaneously. Photon reunites in itself light that has to do only with the sense of sight and therefore it is not physical but a mental sense. At the same time light is physical object because it must have a reflecting matter means.

    Another way photon reunites in itself, of inseparable form, matter and energy. In their interaction photon performs like matter and energy at the same time.
     
  13. Jun 1, 2009 #12

    QuantumPion

    User Avatar
    Science Advisor
    Gold Member

    Re: Light?

    I may not be a particle physics expert (just a lowly engineer :smile: ) but I think there are several problems with your statement... :confused:
     
  14. Jun 1, 2009 #13

    DaveC426913

    User Avatar
    Gold Member

    Re: Light?

    Of this I am not aware.

    Maybe so, but it does not invalidate the claim that anything with matter has mass.
     
  15. Jun 1, 2009 #14

    Hootenanny

    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    Re: Light?

    But that was not QuantumPion's claim.
     
  16. Jun 1, 2009 #15

    Dale

    Staff: Mentor

    Re: Light?

    All fermions have mass, so I agree with the claim that all matter has mass. As Hootenany mentioned, that is not what I was objecting to. I was rejecting the reverse claim that anything with mass is matter.
     
  17. Jun 2, 2009 #16

    QuantumPion

    User Avatar
    Science Advisor
    Gold Member

    Re: Light?

    :confused:
     
  18. Jun 2, 2009 #17

    Hootenanny

    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    Re: Light?

    There are two 'claims' being discussed here:
    1. Anything with mass is matter
    2. All matter is mass
    The first of which is yours, which is what DaleSpam (and I) disagree with. Can you not see the difference between the two statements?
     
  19. Jun 2, 2009 #18

    QuantumPion

    User Avatar
    Science Advisor
    Gold Member

    Re: Light?

    Perhaps I should specify rest mass? I thought the term "relativistic mass" had fallen out of use due to such confusion.
     
  20. Jun 2, 2009 #19
    Re: Light?

    Above not correct is it? Then something has mass but not matter, what is it? Photon?
     
  21. Jun 2, 2009 #20

    Dale

    Staff: Mentor

    Re: Light?

    A pair (or more) of photons, thermal energy, the Z and W gauge bosons, etc. all have mass but are not matter. Thermal energy is probably the most clear-cut example of something with mass but not matter.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: Light is a type of matter
  1. Light Matter (Replies: 31)

  2. Is Light Matter? (Replies: 29)

Loading...