The sun bends the trajectory of light slightly. And a black hole will bend the trajectory entirely. This is all dependent on the proximity to the source of gravity. For a given angle, is there some minimum mass required to bend light light at least that much?

  • 1
    $\begingroup$ How much is "noticeably" ? Voting to Close as Primarily Opinion Based. $\endgroup$ – Abhimanyu Pallavi Sudhir Dec 16 '13 at 3:32
  • 2
    $\begingroup$ @DIMension10 yeah the word "noticeably" is under-defined but you can answer the spirit of the question without defining noticeably. $\endgroup$ – Brandon Enright Dec 16 '13 at 3:49
  • 4
    $\begingroup$ The question also suffers from not having done even any cursory research. Check the Wikipedia page on gravitational lensing and find a precise mathematical answer for any value of "shift" you care to look at. Why did you ask other people to do this work for you? Lazy questions are never good questions. $\endgroup$ – dmckee --- ex-moderator kitten Dec 16 '13 at 3:51
  • $\begingroup$ Related physics.stackexchange.com/questions/90591/… $\endgroup$ – John Rennie Dec 21 '13 at 9:49

I believe you've already spotted the answer to your question with this sentence:

And a black hole will shift the trajectory entirely. This is all dependent on the proximity to the source of gravity.

You can "shift light" (bend its trajectory) as much as you want with as little mass as you want using a black hole. Just let the light get arbitrarily close to the event horizon. There isn't any (practical) lower limit on the mass of a black hole so there isn't any particular mass required to bend light. Just huge densities which will cause the curvature of space needed.

  • 2
    $\begingroup$ Please leave a comment if you are going to downvote. $\endgroup$ – Brandon Enright Dec 16 '13 at 3:54
  • $\begingroup$ So, does any density of matter bend light, albeit extremely slightly? $\endgroup$ – aaaidan Dec 18 '13 at 8:28
  • $\begingroup$ Yep! Everything that has mass warps space a tiny bit and therefor causes light to bend. $\endgroup$ – Brandon Enright Dec 18 '13 at 16:01

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.