Hi! I'm a student reading a book given to me by my teacher about relativity and spacetime. It says that the separation between events in spacetime is measured in "intervals," and I can understand that part.(adsbygoogle = window.adsbygoogle || []).push({});

What I don't understand is why you subtract the squares of the distance in space instead of adding it to the square of the separation in time to find the interval because I am picturing interval as the hypotenuse of a right triangle with legs that are separation in time and separation in space.

And another thing... I'm having trouble understanding why the closer you get to the speed of light (let's say on a journey to another galaxy), the slower time actually goes for you, but not for others who stayed on Earth.

Aaand one more... How can events that are separated in space and time not be separated in spacetime because interval is zero? If they happen 6 meters apart and 6 seconds apart, then interval would be zero, right? But they ARE separated in space and they ARE separated in time, so it just doesn't make sense.

Thanks!! And please bear with me; I have not been learning this for more than a week or two :)

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# Spacetime Interval

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