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!

Does einstien really explain everything about gravity? Is there more?

  1. Mar 16, 2009 #1
    Although Albert Einstein had explained the new picture of gravity through his theory of general relativity, by explaining that gravity is the warping of spacetime, did he explain why mass actually warps this fabric of spacetime?
  2. jcsd
  3. Mar 16, 2009 #2


    User Avatar
    Staff Emeritus
    Science Advisor

    Didn't you ask this earlier?
  4. Mar 16, 2009 #3
    The answer to your question is no. I am not a GR expert but I have studied the theory in mathematical detail and the underlying fact that gravitational effects are caused by mass-energy seems only to be known by experience i.e. it is not deduced mathematically (a priori) but only empirically (a posteori).
  5. Mar 16, 2009 #4


    User Avatar
    Science Advisor

    Neither Einstein nor, as far as I know, any scientist has ever claimed to explain how mass is "causes" gravity. Newton said, in regard to that question, "Hypothesen non fengo", "I frame no hypotheses" and it is still true. That, I suspect, would be one of the deepest questions of physics.
  6. Mar 17, 2009 #5
    Yeah I did, i wanted to delete the other one first but i didn't know how and i wasn't sure if i can.
  7. Mar 17, 2009 #6
    mass or energy creates gravity not just mass.
  8. Mar 17, 2009 #7


    Staff: Mentor

    To follow up on cragar's point. The source of gravity in GR is the stress-energy tensor which includes energy (mass often being the dominant source of energy), momentum, pressure, and stress. It is incorrect to say that mass alone causes gravity.
  9. Mar 17, 2009 #8
    Okay, but the question wasn't what creates gravity, the question was why does mass/energy cause spacetime to warp? On a very fundamental level.
  10. Mar 17, 2009 #9


    User Avatar
    Science Advisor

    Define "very fundamental level". :smile: Also don't forget that curved spacetime is just a mathematical model. You could just as well ask: Why does force change the velocity of a body. The answer is: Because force is a mathematical abstraction that was defined this way.
  11. Mar 17, 2009 #10


    User Avatar

    Staff: Mentor

    Any problem in science or philosophy or anything else in life can be turned into an undending string of "why"s that eventually become unanswerable except to say "that's just the way it is". That may be unsettling to you, but it is a reality that you must deal with - scientists do and as a result, there is a limit to how far they will go with such questions. Eventually, they really are pointless. They don't add any value to scientific knowledge.
  12. Mar 17, 2009 #11


    Staff: Mentor

    By the way, TOE Dream, that is what the word "fundamental" means. If there were an answer to the question "why" then that answer would be the fundamental one.
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Similar Discussions: Does einstien really explain everything about gravity? Is there more?
  1. Gravity explained! (Replies: 39)