All Questions
5
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What does hypersurface of simultaneity exactly mean?
HSS - "Hyper Surface of Simultaneity"
Listening to different sources online I understood that HSS for a observer represents the points that are at same moment of time.
Consider a 1d world. ...
14
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3
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879
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Why are observers/reference frames able to see themselves moving through time but not through space?
All observers are stationary in their own reference frames.
That is, their space coordinates are constant at all times (in their frame).
However, they can see themselves moving through time.
What ...
- 1,421
0
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2
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Why do we locate stars based on the light we see from earth?
Mapping space from our milky-way to Laniakea and the CMB, we always put a star or galaxies position from the light we see in that 3d coordinates of the universe.
But really if a star or galaxy we look ...
1
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2
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77
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Acceptable parametrizations of curved spacetime
When we parametrize an (say absolute) space we have really no restriction (other than smoothness and one value naming) on parametrization.
But I wonder on curved spacetime (also an absolute thing) ...
- 1,409
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Light cone and order of events?
If one event lies outside the light cone of another, can the events to some observers appear in a different order in one reference frame compared to the other, and is this the only time when this is ...
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