While I have used this analogy too - mine has straight lines drawn on it so show how the lines curve when the fabric is stretched. But one needed to be careful if some clever student follows XKCD and asks the obvious (or at least obvious once you hear the question)!

Interesting how many arm-chair physicists have responded to this in a negative manner . . . . this was used for creating interest in physics and educating people, it is positive, it is not spreading religion or dogma, but people seem to want to paint it that way . . . WTF!

So, without mass we have no space-time? Eliminate mass and you can time travel. Right now that is only in your head.

Combining the two words “space” and “time” does not produce spacetime or space-time and is not evidence for the existence of either.

Gravity is generated when a spherical object - moon, planet, star is formed. They are all hot and the heaviest metals stabilize at their cores, with lighter elements towards the surface. The object is essentially a magnet, constantly pulling matter towards its core.

Gravity has no effect on time or space - Gravity is created by matter and only effects matter.

I wonder which student asked who created it? That would have been an inspiring conversation on top of gaining this knowledge.

This video seems like a deep cut, I remember one just like it from seems like 15 years ago that finally helped me wrap my head around the gravity and start my deep dive into the love of physics.

I know this helps visualize the warping of space due to gravity, but it uses gravity to do so. To me this defeats the purpose of the demonstration.

A better method would not use gravity at all. Perhaps use a cloth with a flat grid, then put a pointed object below the cloth to represent a body with mass. Next use a 2D laser to represent a body in motion and show how the path is distorted over the grid.

A creative teacher that loves what he does and will inspire his students.

I have to do this for my students.

What an awesome physics teacher. I still remember the demonstrations that my college physics teacher did. I bet he gets students going into physics research.

Good explanation

The invention of Spandex shouldn't be underrated.