# E=mc^2 in 1,2,3,5,6 dimentions?

1. Dec 14, 2007

### nabki

maybe the universe works in a 4-D enviroment because a 3-D(two space axis, one time axis) enviroment will not allow sufficient energy exchange, and movement in 5-D needs too much energy? just some speculations... anyone more knowledgable on this subject who can help me?

2. Dec 14, 2007

### Mentz114

(my emphasis) The universe can't be in an environment. But I think I understand what you're speculating about.

I believe that it is not possible to get stable gravitational orbits in any configuration with more than three space and one time dimension. So a universe with say, four spatial dimensions would be doomed to kinetic chaos. Two spatial dimensions is not enough, so three seems to be the only possible number.

Off the top of my head, I'd say energy conservation is not a problem because energy is a scalar.

Last edited: Dec 14, 2007
3. Dec 14, 2007

### nabki

I dont mean energy conservation, i mean conversion from one for to annother.

4. Dec 14, 2007

### Mentz114

OK. Well, speculating about how things might be in a different universe from our own isn't really physics because we can't relate our theories to experiment.

As to why we observe 3+1 dimensions, physics probably can't answer that question except to say that's the only way it can be.

If you could show that energy conversion didn't add up in 6 dimensions, it still wouldn't be a 'reason' why we see 3+1 dimensions.

5. Dec 14, 2007

### nabki

hmmmm.... i agree.

6. Dec 14, 2007

### nabki

what im actualy thinking about is the universe actually being 5-D, which can help explain some things like why 90% of mass is unaccounted for and quantum entanglement. I'm letting my mind wander, so please remind me when im not being realistic please.

7. Dec 14, 2007

### pervect

Staff Emeritus
I agree. It might qualify as philosophy if one invoked the anthropic principle.

http://en.wikipedia.org/w/index.php?title=Anthropic_principle&oldid=176543203

As-is, there isn't really enough physics content for the thread to meet our PF Guidelines , so I'm locking it.

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