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Is Gravity a well kept secret?

  1. Mar 14, 2015 #1
    We know so little about gravity and so much about magnetism and electricity, it hardly seem fair to compare any similarities of the three. But! If our universe was created instantly from a singularity as astrophysicists calculate, you’d think we might have more to contemplate than comparing turkeys and chickens.
    Face it, if gravity is an entity unto itself as one of the four fundamental forces of nature and not an offshoot of a third, perhaps we should just be thankful it keeps us from falling uphill and allowing water to flow down hill. I'm almost at the point of believing there is a plot to keeping gravity a secret.
    I know it has been hashed over zillions of times, but my one question still remains: What is Gravity?
    Below is a descent, though overly simplified version of the four fundamental forces.
    Last edited: Mar 14, 2015
  2. jcsd
  3. Mar 14, 2015 #2


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    Science Advisor
    Gold Member

    Hi Orien Rigney
    Can you explain why do you think this to be the case? In what way do 'we' know more about EM than gravity?
    Is this really a fact? How do you know that?
    You'll need to explain what kind of answer you're expecting. In what way do you find the descriptions of gravity (Newtonian or relativistic) unsatisfactory? Can you give us an example of a satisfactory description of another fundamental force?

    I'm pretty sure nobody actually thinks that.
  4. Mar 14, 2015 #3


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    Staff: Mentor

    Actually we know quite a bit about gravity. But the nature of gravity is so different than electromagnetism that there simply aren't very ways of using it like their are with electromagnetism.

    Uphill and downhill is defined with respect to the direction of acceleration under gravity, so of course it works this way.

    A thorough investigation into the Theory of General Relativity should be able to answer this question.
  5. Mar 14, 2015 #4
    For some reason popular science loves to spin the "physicists don't actually know anything" story.
    "We don't know why particles act as if they were both waves and particles"
    "If the higgs boson is not found then everything we know is wrong"
  6. Mar 14, 2015 #5


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    Staff: Mentor

    [Mentors' note: some posts that were pushing this thread off-topic have been removed]

    Science is about how the universe we live in works, not why it has to work that way. Thus, it's often unable to provide satisfactory answers to "what is" or "why" questions. You ask what gravity is, we could give you Newton's answer that gravity is a force resulting from the attraction between masses, and you could reasonably respond with two more questions: What is a "force" and why do masses attract? The only way of ending this regression is get to some statement that's satisfying enough to be accepted without digging yet deeper.

    Thus, when we answer your question with a counter-question ("what sort of answer would satisy you?") we're not just trying to be difficult. We're trying to understand what you're looking for.

    And with that said, the best answer that I can give you is "Gravity is the phenomenon that is described by Newton's theory of gravity and Einstein's theory of general relativity". As Drakkith suggested above, if you want more than that, the next step will be to learn GR.
    Last edited: Mar 14, 2015
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