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A question

  1. Oct 31, 2006 #1
    Does a dimention other than the third dimention possibly eixist? For some thing to exist doesn't it need thickness width and length?.People say time is the 4<sup>th</sup> dimention is there any kind of proff for it:confused: .
    Last edited: Oct 31, 2006
  2. jcsd
  3. Oct 31, 2006 #2
    higher dimensions are mathematical concepts that don't nessisarily deal with reality. In relativity time is treated as the fourth dimension, this is done because of relativistic effects such as time dialation.

    Sometimes in physics the number of free variables is referred to as the dimension, this is different from the number of spacial dimensions, which is, I think, what you are asking about. This is a good description of higher order dimensions in math

    Insofar as wheather there is proof, the proofs of relativity all support the idea of at least 4 dimensions, wheather there are more than that is an open question, string theorests say there are 11, but string theory as of yet has no proof, so no one knows right now.
  4. Nov 4, 2006 #3
    I heard it was 10.
  5. Nov 4, 2006 #4


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    For a phylosophical proof of time as the fourth dimension;
    in roder for an object to exist it must have length, width, depth, and[i/] duration. An object that exist for no amount of time does not exist.
  6. Nov 4, 2006 #5
    Speaking of dimensions.. If i take i gigantic sphere.. And passe it thought Flat World.. (A 2D (Two dimensions) world) What would the citizens of Flat World would see?? In my opinion.. They will see a series of circles starting with a dot then goes bigger and bigger and then go smaller again.. to finally dissapear. In 3D, If a sphere from the 4th dimension passe throught our world... We would see series of spheres... I'm I right? But my point is that we already saw this phenomenon in the universe.. Is it possible that ther IS actually a fourth dimension.. ? Not only in Mathematics?
  7. Nov 4, 2006 #6
    people think that dimensions are some weird airy fairy scifi thing but theyre not. its simply a coordinate system to describe an objects location. as objects have a location in time as well as space you need a temporal dimesion.
  8. Nov 4, 2006 #7


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    Where/when did we already see this phenomenon?

    Note, it would manifest, not simply as a sphere expanding (conventionally it would lose density as it expanded, thus retaining the same mass) but as a sphere mysteriously gaining mass as it expanded, the mass coming from nowhere we can detect.
  9. Nov 5, 2006 #8
    I'm sorry I was looking for that phenomenon they talked about on CBC radio. Unfortunatly I can't find the source so it can't be taken in consideration.

    We would see a sphere expanding and keeping the same mass? So its not just a series of spheres..? But I think your right. Its just like Flat world. The little image shows what I meant about Flat world..

    The image has been taken from (http://tetraspace.alkaline.org/page1.htm) Where they explain clearly what would happen if an 4D object passes thought our world (I just found it :biggrin: ) :smile: And form the site point of view, You are right.

    Thank you for your time.

    Attached Files:

  10. Nov 5, 2006 #9


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    No, a normal sphere would expand but keep the same mass (spreading itself out thinner and thinner). A hypersphere would expand and gain mass, and that mass would be coming from nowhere in our plane of existance, so it would appear to be gaining "mass from nowhere".
  11. Nov 5, 2006 #10
    Ooh.. That does explains some things..
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