1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

How is light affected by the gravity of a black hole?

  1. Jan 8, 2016 #1
    Hello! I am new to this forum, but I'll give it a shot.
    It is my understanding that photons have no mass- but that light is still pulled by the gravity of a black hole. How can something without a mass, and therefore, gravity, be pulled by the gravity of another object? Any insight would be appreciated. I am still just beginning in my physics education, so please correct any errors I have made.
  2. jcsd
  3. Jan 8, 2016 #2


    Staff: Mentor

    Hi Oliver3.141 welcome to PF,

    In general relativity (the theory that describes this) gravity comes from the fact that energy and momentum and pressure all curve spacetime. Light travels through spacetime, so its path can be influenced by gravity. Also, light has energy and momentum and pressure, so it can produce gravity too.
  4. Jan 8, 2016 #3


    User Avatar
    Staff Emeritus
    Science Advisor
    Education Advisor

  5. Jan 8, 2016 #4
    Thank you for your input! :)
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook