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

Two black holes and a particle.

  1. Nov 16, 2004 #1
    I was going to post this in the cosmology chat, but figured it belonged here more than there.

    First I want to take two black holes of equal mass and then place them so that their event horizons are touching (or just overlapping - I'm imagining two spheres placed next to each other). Now what happens to a single photon (particle of any type will work) shot between these two black holes, what hole does it go in? Would it be entirely random? If you shot a stream would would half go in one and half go in the other?

    What happens if event horizons of black holes overlap?
  2. jcsd
  3. Nov 16, 2004 #2


    User Avatar
    Science Advisor

    The black holes would coalesce into one bigger black hole.
  4. Nov 16, 2004 #3
    Without that fact, the photon would travel straight to the part of the black holes overlapping. The equal force of the gravity would cancel out, and cause the photon to remain stationary between the two black holes, and accoding to one theory, could cause it to turn into a small amount of mass.
    Either I hit it on the nose or am totally ignorant.
  5. Nov 17, 2004 #4
    Thanks for the answers.
    And now for the follow-up ones.

    1). What theory is it that says a photon will then have mass?

    2). What happens when the 'points' of the black hole come together? Anything? Nothing? It seems that two objects like that pulling at each other would cause some problems.
  6. Nov 17, 2004 #5
    I think I found it on www.howstuffworks.com. It's something like that the two electro-magnetic forced would become a stationary wave, and could be mass, I don't know, maybe I didn't understand it.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook