B What Is The Energy of a Point In Space?

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The discussion centers on the concept of energy at a specific point in spacetime, particularly in relation to electromagnetic radiation. It explores how different observers can perceive varying energies depending on their position and motion, highlighting the role of the electromagnetic stress-energy tensor in describing these variations. The conversation also touches on the idea that while energy is conserved, it is not invariant across different reference frames, leading to different observations of energy levels. Participants express confusion over the complexities of these concepts, including the nature of energy and its relationship to spacetime. Ultimately, the discussion emphasizes that energy can appear differently based on the observer's frame of reference, while also acknowledging the inherent complexities of understanding these phenomena.
  • #31
How far is it from point A to point B?
 
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  • #32
gary350 said:
How far is it from point A to point B?

I've often thought about that. Seems to me you cannot have a 'point A and a point B' alone. Because as points there's no way to measure their separation.

A dimensionless point has no dimensions in itself. In a surroundings lacking dimensions there's nothing we can say in terms of dimension.

Given a third point we can start measuring. That third point could be part of the first point if it is given dimensions, thickness, height, width...

Then the distance from A to B becomes in terms of A the number of times you can divide the width of A into the interval.

Hence the need for three. Three is the smallest number.
 
  • #33
I think it's time to close this thread as the contributions become more and more meaningless and tend towards unsubstantial speculations.

Thread closed.
 
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