Ok im pretty new to the relativity thing. Im not at university, and I have started studing relativity by myself out of interest - so dont laugh at these stupid questions pleeease :) 1. Biggun - the fabric of space time - is this purely theoretical - to help us understand gravity, or is it a real thing? Furthermore, why and how are we able to think of space and time in this way? 2. Light is effected by gravity. Does light have mass then? 3. From what i understand of the fabric of space time, it is like a weight on a taught pice of cloth. anything coming towards towards the wieight will be attracted to it, and begin circling it? Why doesnt it just fall into it? 4. What, very broadly is the schism between Quantum, and Relativity? Very VERY broad questions... sorry Cheers.