Certain people who visit here will say the following is obvious. Others might think it’s not even English. But for me this was something that was sitting there to be realized, but I’d never quite noticed. I’m watching a program about string theory (a way of describing how the universe works at the most fundamental level), and one of the things they’re discussing is Einstein’s work on gravity and space-time. They’re showing a familiar image, a model Sun distorting a large taut sheet (space-time) like a bowling ball, with a model Earth following the distortion in the sheet to create its orbit. What I hadn’t ever thought about before is that this is an analogy. Not in the sense that the Sun isn’t really a bowling ball (though if you’re in doubt, it’s not), but because space-time isn’t a sheet. it is, in fact, four dimensional. So what is often presented as a dip in a sheet is actually a contraction in three-dimensional space, with some degree of persistence in time. So a more accurate analogy, though less useful, would be to stick a straw in a bowl of jello/jelly, and suck on the straw just enough to have the gelatinous substance distort, in three dimensions, towards a point (the end of the straw.)
Don’t worry, I’ll get back to important stories about supermodels and worthless journalists soon.