Re: RE: What do you believe?Jan 25th, 2005
Quote: Originally Posted by zenfisherBut isn't space and time the same thing, and isn't gravity a bent of that fabric called space time?
I tend to view it as sixth dimesional including length, width, height, space, time and gravity.
At least in the intuitively familiar world of Euclidean geometry. that's the way it is. Relativity adds a fourth term to that calculation, to account for the fact that you're also separated in time from that location. In Euclidean terms you calculate what's called the space interval, usually called s in most references I've seen, as s²=x² + y² + z². In relativity theory you calculate the spacetime interval as s²=c²t² - (x² + y² + z²), where c is the speed of light and t is time. It has to be done that way or different observers won't agree on where things are or when they happen.
In general relativity, we find that those coordinate axes along which we measure x, y, and z are not straight lines, but curves defined by the distribution of mass, which is what leads to the notion that gravity is a distortion in the shape of space caused by masses. So no, space and time are not the same thing, they're parts of one thing, and there are not six dimensions in relativity theory, there are four, which define spacetime, and the presence of masses changes its shape.