Effect of 3D photons on a 2D universe. Help me understand?

[omoplata]

Hi,

I just saw this video on youtube, originally from Carl Sagan's 'Cosmos', about a 4th spatial dimension.

http://www.youtube.com/watch?v=Y9KT4M7kiSw&NR=1"

So what happens when the photons that are traveling in 3D hit an object in a 2D plane universe. To a 2D object it seems like photon appearing from nowhere? And therefore matter and energy appearing from nowhere?

Not only for light, but if any piece of matter went through the 2D plane universe wouldn't that imply that the conservation of energy doesn't hold in the 2D universe?

And what about the conservation of momentum. If a 3D object hit a 2D object with any velocity perpendicular to the plane, then that would push the 2D object out of the plane and thus out of its universe (provided they interact).

I would like input from you guys as to whether my reasoning is correct. And is there any way of making objects in a 2D plane universe and a 3D universe interact while holding the conservation of energy and momentum in both universes?

I just realized while I was writing this that we don't actually see any really 2D things. I mean, everything we see have a thickness, even if one atomic layer thick. So even if there was a 2D universe within our 3D universe, we wouldn't see it because it has no thickness?

 

[General Black]

Ok i was going to be serious, but watching a minute of that...you actually watched all of that?
What he said was bogus he began his little "session" by saying we are flat, that we are "2d" don't listen to this.
"not meaning the OP i am referring to the video link"

 

[omoplata]

Well, why are we NOT flat? I mean, why do we have 3 spatial dimensions? What's so special about 3 ?

 

[General Black]

Drawings are flat they have no mass or volume of whatever
we or any object have length, width and height. therefore making us 3d i guess
and what he implied basically that a 4th dimension is just a 3rd inside another
as to your question that is virtually improbable. I'm no professor but honestly if no one ever brought up the theories of dimensions guys like the dude on your video would be drawing on the walls with crayons and giggling.

 

[omoplata]

Oh, I did not interpret the video as Carl Sagan is saying people actually have evidence of a 4D universe, if that's what you mean.

For one thing I'm questioning his assumption that you can see a 2D universe from a 3D one. The example he used on this doesn't really seem to work.

The other thing that bugs me is, why 3 ?

 

[General Black]

yea um...ok. Video games.

 

[omoplata]

Oh, you posted #4 on this tread while I was writing up post #5, so #5 is not a reply to #4. Sorry about any confusion.

I disagree that drawings are flat. A drawing is a thin layer of paint on a surface. The paint has a thickness.

 

[General Black]

Digital worlds.