Gravity Demo Part 2 Basic Demo

hi my name is Eddie and I'd like to show you a little bit of a demonstration about gravity so first off let me show you what I am talking about there is a picture of the earth going around the Sun and people have known for a long time that the earth goes around the Sun but they didn't know why that was and so what I'm gonna try to do right now is create that same image two different ways of a planet going around the Sun what happens up on the screen is the reality that's what you see in the space what happens over here is sort of like the behind-the-scenes like in The Wizard of Oz this is like behind the curtains this is not what you would see if you were to look into space that's the only thing that you see is the motions so let me show you a couple ways to do that here is the first way first of all I need a star star goes in there and here was Sir Isaac Newton's way of making a planet go around the star ball on a string swinging round and round if you look up at the screen you can see that it looks just like a planet going around the star and the reason is because I've got this string over here they're connected that's what Isaac Newton called gravity why did you say that because watch what happens if I let go of the string sort of flies off into space so why is it that the earth does not fly off into space why is it that the earth keeps on going around the Sun according to Isaac Newton it's because of some connection between the star and the planet which he called gravity problem is you couldn't see that there is no really a rope over there there's nothing that you can't like feel or smell or see or anything so he just imagined that there must be some sort of connection or else how else could you get that if there were no connection for hundreds of years people looked for that connection couldn't find it and then Einstein came along and Einstein said you know the only reality is what's up on that screen the only reality is a planet going around the star is there another way that I can get that same image so this was his mental way of doing it he said that there's an extra dimension and you can see it over here an extra dimension that you don't actually see if you were to look up in the space and that extra dimension is curved and if I were to roll a ball around that curved space-time if you were to look out in space up there on the screen it looks like a planet going around the star but it's not because they're connected with a string it's because of this curvature over here and as a matter of fact the only thing that this ball knows about is the part of the plastic that it actually rolls over and so it's that curvature right where it's rolling over that causes that what's more I'm Stein said this I'm gonna pull out the fabric of space-time and to make it a little bit easier to see let me put a grid on this fabric of space-time what Einstein said was this if you don't have anything out in space that's a flat space if you were to take a planet a ball whatever it is a rocketship and roll it it would make a straight line in that space-time watch it up on the screen I roll it and it makes a straight line but according to Einstein if you go and have a star that star will bend space-time in that extra dimension that you can't see so you can't see it bent up over there but you can see it here and that bent space-time if you roll the ball see now it looks like it's going around and around that planet so according to Einstein there is no connection between the star and the planet what you have is the star bending the fabric of space and this little fabric pulls on that which pulls on that which pulls on that which pulls on that there is no action at a distance there's only this pulling on the stuff right next to it and then when the ball goes around and around it's because of that curvature going around here's another thing he said was that if you have a heavier star a more massive star and put it in it's going to curve space-time even more so watch this it really looks like a planet going around the star but once again it's not because there's any connection it's because there is an extra dimension that you can't see out in space the star curves that extra dimension of space-time and that curve space-time is what causes it to go around this is Einstein's general theory of relativity and it is how he explained why planets go around stars so the points that you want to get across are the only reality is what you see up on the screen and that's what you keep on directing the visitors attention to there are two ways to create that image one way to create that image is using Newton's method of a string connecting the planet and the star but there were problems with that and Einstein's method which is the star warps space-time and that warped space-time is what causes it to go around those are the basic points to get across in a minute I will show you a number of other things that you can show but if you get those points across that would be a success

Channel: SpaceSciNewsroom

Views: 1,736,614

Rating: 4.8143058 out of 5

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Id: MkbUzfTq3w4

Length: 6min 49sec (409 seconds)

Published: Fri Jun 14 2013