Free Fall vs Acceleration: Einstein's Theory Explained

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Discussion Overview

The discussion revolves around the concepts of free fall and acceleration as explained by Einstein's theory, particularly focusing on the equivalence principle and the distinctions between inertial and non-inertial frames of reference. Participants explore the implications of these concepts in understanding gravity and acceleration.

Discussion Character

  • Exploratory, Technical explanation, Conceptual clarification, Debate/contested

Main Points Raised

  • One participant questions how the concepts of free fall and acceleration work, noting the importance of frame of reference.
  • Another participant explains that in physics, indistinguishable situations imply equivalence, using the analogy of being in an accelerating box versus standing on Earth.
  • A third participant suggests looking up the "equivalence principle" and differentiating between "proper acceleration" and "coordinate acceleration" for further understanding.
  • A later reply provides a link to an external resource for additional context on general relativity and gravity.

Areas of Agreement / Disagreement

Participants express varying levels of understanding and interpretations of the concepts, with no clear consensus reached on the explanations provided. The discussion remains open-ended with multiple viewpoints presented.

Contextual Notes

Some assumptions regarding the definitions of inertial and non-inertial frames, as well as the implications of the equivalence principle, are not fully explored. The discussion does not resolve the complexities of these concepts.

TheWonderer1
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How does this work exactly? I can understand depending on frame of reference but I read that Einstein stated there is a right way to think about that based on inertial and non-inertial frame of references.
 
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In physics, if there is no way to distinguish two things, they are the same.

If you are in a box that is accelerating, what you experience is being pushed to one side of the box.
You would intuitively assign that side the special label "floor", and how hard you press into it would be your "weight".

This is also what you experience standing in a box on the Earth, but not when you are in a box in freefall... it follows that standing on the Earth is not distinguishable from a situation where you are accelerating while freefall is not distinguishable from the situation where you are not accelerating.

That's not all there is to it - but it's a starting point.
 
TheWonderer1 said:
How does this work exactly?
Look up "equivalence principle" and "proper acceleration" vs. "coordinate acceleration".
 

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