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Can someone explain what the 4th Dimension is?

  1. Jul 14, 2004 #1
    Can someone explain what the 4th Dimension is?
     
  2. jcsd
  3. Jul 14, 2004 #2
    einstien stated that the 4th dimension is time, for example; if you wish to meet somebody some were you would give him directions as follows.
    head north 100miles( 1st dimension) turn right and travel 2 miles(2nd dimension)
    go up the flight of stairs to the top (3rd dimension) and meet me at 4 oclock(4th dimension).
    This is only an anology and probably is not the best example
    other people may have different views but i hope it helps
     
  4. Jul 15, 2004 #3
    I always think of it like this. The universe is expanding, right? So if you wanted to tell me where to find some distant star you would have to tell me where to look (3 dimensions) and when (4th dimension) cos it aint always gonna be there. Kind of hard to express but I hope this helps.
     
  5. Jul 15, 2004 #4

    HallsofIvy

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    A "dimension" is simply a number used to specifiy something of importance. Physics deals with "events", things that happen at a particular position at a particular time. The first three dimensions give the position, the fourth the time.
     
  6. Jul 15, 2004 #5
    Dimensions can be thought of some kind of parameter. For example, let's say you are walking from A to B. In 3D, we can only describe where you are, but in this case, you might be in A, B, or in between, if we don't mention the time. But, if we mention a certain time, let's say time 0(ie. when you first started walking), we will know that you are at A for sure, since you started there.
     
  7. Jul 17, 2004 #6
    It is a special case only. Look more widely, guys.
    In the general case, (n+1) dimension activates all previous (n) dimensions.


    Michael
     
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