What is the difference between time-like and space-like separation?

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SUMMARY

The discussion clarifies the concepts of time-like and space-like separation in the context of spacetime. Time-like separated events allow for causal influence, meaning that if event A occurs before event B, all observers will agree on this order, and an object can travel between them at a velocity less than the speed of light (vc) to connect, resulting in no definitive temporal order. This distinction is visually represented on spacetime diagrams, where time-like events lie within each other's light cones, while space-like events lie outside.

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Please,can you simply explain the meaning of terms time-like,space-like,time-like separated,space-like separated.I searched in web for an hour but all explanations are very complicated.I didn't understand anything.

IS the time-like separated means just difference in time of two points in some frame at dx=0 at this frame?
 
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If two events are time-like separated, then an object can travel from the first event to the second event with a velocity v<c.

Events separated by a time-like interval are always arranged in the same order in time. That is, if an observer O deduces that event A happens before B, then another observer O', moving relative to O, will also come to the same conclusion. There is a before and after. And there is a possibility that that event A will influence event B. (Cause and Effect.)

In a space-like interval, an object can be present at both events only if it travels at a velocity v>c. Since no object with mass can travel at such a speed, the two events are not causally connected. Also, there is no particular order between A and B(in time) if they are space-like separated.

On a spacetime diagram, for time-like events A and B, B will be within the light-cone of A and vice-versa. For space-like intervals, one event is outside the light-cone of the other.
 
Thank you very much.It seems to that I understood something.
 
The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

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