Recent content by markf

  1. M

    What is the heaviest thing in the universe?

    What's the heaviest thing in the universe?
  2. M

    Graduate Is Gravity Really Just Curved Spacetime?

    I read somewhere that gravity is not a force. Is this true? What does it mean?
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    Undergrad Einstein's Train Metaphor: Explained

    Many thanks
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    Undergrad Einstein's Train Metaphor: Explained

    Yes, Relativity of Simultaneity
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    Undergrad Einstein's Train Metaphor: Explained

    Can you explain Einstein's train metaphor/thought experiment. Thanks