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3-d A thought from 9th grade

  1. Jun 2, 2004 #1
    Dimensions War--

    This is something that I thought about in 9th grade in geometry and decided it would be nice to see what others thought

    Remember Geometry?
    I do... sort of...
    I remember sitting there boreed as the teacher rambled off and I would start to either
    a. play nibbles
    b. sleep
    3. think

    on the occational choice 3, I began to think about some of the work that I was supose to be doing... it was stuff finding the area of various 2-d shapes. I quickly finished the worksheet the correct way, then frustrated with how much this work resmembled "busy" work I decided to prevoke conflict as I liked to do so often. I asked for a new sheet and filled in 0 for every answer. My logic was as follows. Nothing in the world can be anything less than 3 dimensions to be a part of this physical world. If it only had had one or 2 then it would be missing the third. Thefore when you rotate an object to the dimension that it would be missing it would have 0 for a width. Therefore the object could not exist. I argued with my teacher that measure of area should be considered with a standard unit width of one... No mater what the suface area is... it needed a surface and in order to meet this need it needed all 3 dimisnions... save 2 dimensional and one dimensional objects fot bed time stories. The teacher never really gave me a straight answer... but fromt hen I just tried to write up a paper, however being in 9th grade I got tired of writing it... but the just was that since nothing could just have 2 dimensions or one, that anything less thatn 2 dimensional was imaginary....

    However then came physics in which i took a keen interest in the idea of string theory and folded dimensions with models of something like Kalabe Yao Shapes (pronounced that way obviously by now u realize i am not great in english especailly in spelling) with shapes up to 11 dimensions.

    My question is how many dimesions are there, and are the 11 dimensions in string theroy predicted differnt from the 3 spacial dimensions. Also how is time lumped into the dimensional category. It seems to stick out like a sore thumb. True you can be x,y,z at 5:00 pm however others describe shape versus time being lumped in as a location. It seems to be similar and yet very differnt at the same time.

    Well thats my thought for the day....

    Maybe I will add more later.
    Last edited: Jun 10, 2004
  2. jcsd
  3. Jun 2, 2004 #2
    And whoever said geometry lessons taught you nothing?

  4. Jun 5, 2004 #3
    I know nothing about string theory (ashamed) but i think i can answer your question.
    As you may know there is mathematicall models, and physical models. In mathematical models you can have as many dimensions as you want, say 600. Those models are used to solve problmes. I'll give you an example: When you try to find peformance of an car, you'll find that it is dependent on various factors like temperature, weight of the car, efficiency of the engine, humidity, type of the tires, type of the road etc...
    When you attempt to draw a graph of the performance you'd need as many dimensions as the number of factors +1. You can think of it this way, you have all the factors as inputs, and they result in one output which is the perfomance of the car
    ( F(x,y,z,k,....,a)= performance).
    Also, there is something which is called fractals, which are incomplete dimensions if i'm right. I never studied them cause i'm a computer eng. major. Basicaly fractals are when you have 1.5 dimensions, 3.4- and so on..so dimensions don't only exist in whole numbers...

    Now comin to the physical world, we only use mathematical models to try to get the best approximation as we could get to explain a certain phenomenon. And that's why prolly in physics they use the 11th and 12th dimension. (My last argument could be wrong because i dont' have insight in those fields).
  5. Jun 6, 2004 #4
    thank you for your response... however actually the model in physics does refer to 11 real dimensions not only for mathmatics purposes, but they describe physical wrapped dimensions. I am still wondering about how 2 dim and 1 dim objects could be real.... it seems they must be imaginary. Again thank you for your response.
  6. Jun 6, 2004 #5
    It's better to have more peeps answering this question, cause i kinda felt that my responce wasn't perfect.
  7. Jun 30, 2004 #6

    You state that if a 2 dim object can not be real because we are in a 3d world, then shouldn't you also state that 3d objects can not be real because we are in a 11d world?
  8. Jul 2, 2004 #7
    Actually no aychamo, besides the normal 3 spacial dimensions, the other dimensions do not interact of the same level. 4d is time, there is a 4th spacial dimension, but that isnt envolved. Since the other d's dont nessesarially involve "space" or distance, or spacial dimension, it is not correct to say that a 3d object cant be present in a 11d, or 10d world. If that was true, then we wouldn't exist, so obviously the others allow for the 3spacial to exist along with them, and that is required in the universe for there to be that many.

    correct me if I'm wrong.
  9. Jul 3, 2004 #8
    Aye, I agree with you. I was making an inference from the logic that Tom was using. Tom said that 2d objects shouldn't exist in a 3d world.
  10. Jul 3, 2004 #9


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    Science Advisor
    Homework Helper

    The units used to measure the objects are two dimensional (m^2) and not three dimensional (m^3) so the value is non-zero.

    And the questions don't say "make up extra rules here". It's pretty clear what they want you to answer.

    I mean honestly, I could use the same argument for saying 3d objects don't exist, or 4d. Or 5d. If seen from a 6d perspective.
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