changing the laws of physics

[Austin J]

Well, some of you guys are taking this question really deep. I however, will just look at it as screwing around with illogical made-up laws.

I've done a few funny things just to screw around when simulating physics situations with C++. I've done silly easy things such as reverse gravity, then weirder things like try to some how simulate a photon(a little fake box one) getting trapped by a black hole. That proved much more difficult than I thought it would be however!

[htirwin]

We only changed one parameter in gravity. You can do that in the maths equations and just see what result you get. Sure, it's not like super scientific or anything, but it's a fun thread.

But gravitational fields aren't generated by books, they are generated by the particles that make up the book individually, even though most of the particles that make up the book are not attached in any significant way to most of the others in the book. For example, you could have a giant ball of loose styrofoam peanuts, does it fall faster than a small rock of a smaller weight in this model? It has more protons and neutrons.

To make it meaningful, you have to clarify the "something" that, if is heavier, falls faster. Do you go down to molecules, atoms, protons and neutrons? If you go down to protons, or lower, where the real gravitational interactions are at, then it changes nothing because all protons are the same weight. If you go to elements it may be interesting, but then you introduce the idea that the bonds between the particles are part of the gravitational phenomena. If you go to molecules, then chemical bonds would be part of the gravitational phenomena. if you go further then whether the collection of particles has a single name/definition in the dictionary, is part of the gravitational phenomena?

So it means everything what you have actually changed about gravity before you can say anything about what the consequences are. If you take away the notion that individual fundamental particles themselves interact without any notion of the collection they are a part of, then you have to provide a new way that gravity interacts. As proposed it is as if gravity interacts with "something" as if it were the fundamental thing that is interacting per that unit "something". So what is that "something"?

[Mats]

Yeah definitely a good point there htirwin. I was just taking it that greater density objects fell faster when I heard the word heavier.

However, as long as you assume basically any model in which average gravitational attraction is stronger, you will get a collapsing result.

[Stormboy]

Since I didn't give any reply to the OP's original question:

anyways, lets say we live in an alternate universe that is exactly the same as this one, except for one change in the laws of physics. the heavier something is, the faster it falls. my question is what would happen if i put a piece of paper underneath a book and dropped it.

Since the book is heavier, its acceleration will be more (it will fall faster) than the piece of paper. The paper will fall slowly and the book will fall faster and since the paper is below the book, it will be pushed down by the book. The air resistance will push the paper up so the paper will be stuck at the bottom of the book. Therefore, the paper will move with the same velocity as the book.