The reason planets orbit stars is due to gravity. The reason stars glow is due to heat. What’s the reason for gravity existing?

  • Pons_Aelius
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    121 year ago

    There is no reason.

    It simply is.

    Humans have found 4 forces that control the universe. (there many be a fifth involving quarks but that is still to be proven)

    Electromagnetism

    Gravity.

    Strong Nuclear force

    Weak nuclear Force.

    Everything we experience in this universe is the interaction of these 4 forces.

  • @Arete
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    31 year ago

    I’m a decade out of school but I think you can show that any theory that allows a massless spin-2 particle necessarily gives rise to gravity as a force. I remember seeing how this exact particle emerged when solving equations of motion for bosonic string theory and being pretty impressed (iirc it was a symmetric traceless rank 2 tensor field or something similar and the Prof had to handwave a bit on it being equivalent)

    So maybe we have gravity simply because there are a lot of ways to construct a universe with it and only a few special cases without it.

  • style99
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    21 year ago

    This is a fair question, and I doubt we’ve really heard the last of this subject.