Naked Science Forum
Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: Kryptid on 24/02/2011 08:09:58
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So I was looking up some stuff on the supposedly haunted/ufo-infested Skinwalker Ranch (fringe stuff as far as many of you are probably concerned) and there was talk of beings from higher dimensional space as possible culprits.
That got me wondering and put many questions into my mind. Would matter from a 4-dimensional universe even be capable of interacting with our 3-dimensional world? My personal guess so far is that the answer is either "no" or "only with difficulty/certain methods". Obviously, I mean 4 dimesions of space (not worrying so much about the dimension of time right now).
In order for us to see something, light has to interact with an object in some way. If a piece of 4D matter passed through our 3D space, we could only see it if somehow photons could interact with it. To me, that seems unlikely. Could 4-dimensional matter absorb/reflect 3-dimensional energy from light? Wouldn't there have to be some analogue to atoms in the 4th dimension in order for that to work?
I know that some things are necessarily different in 4 dimensions. The inverse-square law that affects the rate at which radiation and fields lose their strength is a product of the fact that we live in a universe with 3 dimensions of space. In 4 dimensions, that strength would fall off at a faster rate since there would be more directions for the light rays/field lines to spread into. I think it's something like...an inverse-cube law? I can't remember what it was. However, what I DO remember is that supposedly atoms as we know them would not be stable in a universe where the field strength dies off so quickly. What consequences would that have for such matter? Would only degenerate matter exist in 4 dimensions?
What about subatomic particles? I have a feeling that the spectrum of particles itself might be different and is somehow linked to the number of dimensions of space and time but that is just speculation. If I recall correctly, the majority of the mass of the proton comes from the motions of the quarks inside. Since there is more space for the quarks to move around in 4 dimensions, might the 4-dimensional analogue of the proton (if it did exist) have a different mass than our proton?
If a four dimensional universe existed, how would we detect it? Would we be able to detect it at all?
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We do live in a four (or more) dimensional universe just how do you think the concept of gravity "curving" space works without at least one more dimension. it is not just space-time as a four dimensional entity.
As you suggest it appears that long term dynamic structures involving angular momentum and energy will only work in three dimensions so as we can only experience long term structures we would only experience the three dimensional bits.
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It all depends on how you visualize those dimensions I think. Myself I look at them as something magnifying. Like bending out in ways we can't see. dimensions is something we defined from the reality we see macroscopically. Then we apply the same ideas on stuff we can't see at all. All we can see will be in 3D as far as I know, represented by the radiations interaction with us. That we call light 'non-dimensional' doesn't mean a thing there, and do not give our old ideas of what 'dimensions' should be any validity. You could as easily go out from lights 'non-dimensionality' and define all else as a illusion if you like. It's just the other side of the coin, so to speak :). The best way I've found to think of it is the way fractals can be magnified, still keeping themselves intact. That is what 'dimensions' are to me, with every 'scale' you observe a representation of 'emergences'. I never liked the idea of the universe being some sort of puzzle in where the pieces would be represented by singular 'dimensions' that you 'put together'.
How?
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orbits are unstable in an inverse cube field.
magnetism becomes weird in 4 dimensions too. it becomes a tensor field rather than a (pseudo)vector field.
other than that things should work fine in 4 dimensions.
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I know what scalar fields and vector fields are, but what's a tensor field?
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Read this one, (http://en.wikipedia.org/wiki/Tensor) and then take a look at the pretty pictures :) (http://web.engr.oregonstate.edu/~zhange/tenfld_design.html) Those two together will give you a feel for it.