What are the 4 dimensions (4D) and what does everyone mean?
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Imagine you put a yardstick on the floor facing exactly north and south. That would be the first dimension. Moreover, north and south anywhere in the room would also be the  first dimension. Now, put a second yardstick down on top of the first but facing east and west so they look like a big plus sign. That would be the second dimension. Notice, and this is very important, the two yardsticks are at right angles to each other - 90 degrees. All dimensions must be at right angles to each other. Now, put a third yardstick with the other two but remember, it must be at right angles to BOTH of them. There is only one way it can be oriented - in the center of the plus sign standing straight up and down. This is the third dimension. Take time either to try it or to actually build what I have just described using rulers or pencils and satisfy yourself that all three dimensions are actually 90 degrees to each other. Now go one step further. Can you add another yardstick (or pencil) which is at right angles to ALL THREE of the others? Before you exprience brain burnout I'll answer that for you. No - although you might like to try. You can't do it because we live in three dimensional space. However, many scientists feel that there is a fourth dimension although it can't be drawn or built - just imagined. Remember, it would have to be at right angles to each of the three spatial dimensions. Many scientists think the fourth dimension is time. No matter how we turn or in what direction we face, time is always like a yardstick facing behind us into the past and forward into the future. Remember, this is just a theory, an idea supported by many facts and observations but one which has not yet been proven. Are there more than four dimensions? Possibly. In math we can have as many dimensions as we want but math is strictly a mental exercise. The fact that math so nearly predicts what the actual universe is like is a tribute to the perfection of the universe.
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First of all, you want to come to grips with the fact that you don't really have an appreciation for 1, 2 or even 3 dimensions. We talk about up, down, left and right as if they were things we could grab onto, but cannot really.\n\nBecause we don't have a way to look at dimensions literally, it becomes a matter of concept and deffinition.\n\nConsider the concept of one dimension. It means merely that something can travel in only one of two directions, either foreward or backwards, but that's all.\n\nIn two dimensions, one gets to travel in 4 directions and combinations of those four.\n\nAbout here, you are probably visualizing what I am talking about, but that is a mistake. We want the concept without the visual because the visual will get us into trouble later.\n\nOk, 3 dimensions? Add two new directions which you can combine with the others to make 6 ways to go and the combinations of those 6.\n\n4 dimensions? Add two more for a total of 8.\n\n5 dimensions? Add another two new directions for a total of 10 ways to travel (along with mixtures of the 10).\n\nSo, what shall we call these directions? Traditionally, the first eight are called left and right, up and down, foreward and back, past and future. The next two we can call thither and yon.\n\nNow, notice that if you always just travel left and right, you can't really know if you are in some larger scheme and just using two of the 10 ways to go. That's the status for us in four dimensions and thinking about 5. We travel actually in 7 directions, because we are always going forward in time. \n\nReally, the only thing that makes additional dimensions hard is trying to visualize them. But you don't really visualize time or 'left' anyhow, so if you can just focus on the meanings that will get you over the hump.
30390
go to www.google.com and type in \n\nriemann spaces  3 4 dimensions\n\nit will bring up alot of information for you to look at
340934
I think there's several ways to conceptualize this stuff.  First of all, a number raised to a power doesn't necessarily involve any extra dimensions at all.  3^3 = 9, and 9 is a number that can be graphed on a one dimensional line.  Consider, what dimension does 4^1.5 exist on, the 1.5th dimension?  That doesn't make much sense.  The answer is simply 4^1.5 = 8, and 8 can also be graphed on a one dimensional line.  Or how about 3^pi?  Do we get the pi'th dimension?  Mmm, a dimension of pie...  Er, what was I saying?\n\nAnyway if we want to have a real cube in three dimensional space, we need at least three points in 3D space to represent it (actually we can represent it with 6 pieces of info instead of the 9 x,y,z's that make up the 3 points).  So what happens when we "cube" those three points, e.i., raise the points of that cube to the 3rd power?  We end up with a bigger cube in three dimensional space, just like we ended up with a bigger number in the one dimensional space example before.\n\nHowever, the answer to your question might possibly be 5 dimensions.  If you think of a number to the first power as being in the first dimension (on a line graph), and you cube it, it only moves up two dimensions, from the 1st to the 3rd (a cubic graph of space).  So taking a 3 dimensional number and cubing it would also move it up just two more dimensions from the 3rd to the 5th.  I can't think of any way to write that with a conceptually valid math expression, though.\n\nI'm not exactly sure how we'd get to 6 dimensions, unless you're thinking something like x^3*x^3 = x^(3+3) = x^6, but that doesn't seem reasonable to me, either.\n\nInstead, let's try this:\n3^1 = 3\n3^2 = 9, our previous number times our base number, 3.\n3^3 = 27, our previous number times our base number, 3.  So the cube of 3, our starting example, is 27.\n\nWhat's the cube of our cube (27)?  I.e., what's 27^3?\n27^1 = 27\n27^2 = 729 (27 times 27)\n27^3 = 19683 (729 times 27)\n\nSo for our final number, we want to find out how many "dimensions" it took to reach that, right?  So, what exponent of 3 does 19683 represent?  In other words, 3^x = 19683, what's x?  To find that out, we need to convert it to logarithmic form.  log_base3(19683) = x.  x = 9.  On a standard calculator, enter log(19683)/log(3) to find that out.  And you can check the answer by doing 3^9, which comes out to be 19683.  You can also follow that whole process using starting numbers other than 3.\n\nTo write it out more formally, (x^3)^3 = x^(3*3), by one of the properties of exponents, which = x^9.\n\nOr what if we did x^(3^3), which would be x^27.  27 "dimensions" seems far too excessive for the cube of a cube, to me.\n\nSo, my final answer is 9 "dimensions", though with the caveat that I think "dimensions" is misleading.
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ALL of scientific theories are just "made up" to try to explain observations. All theories are expected to be eventually superceded by something that explains more of the data. \n\nAnd that includes "space time", which is just a shorthand way of saying the 4 dimensional space we live in: 3 space dimensions and 1 time dimension. This concept might very well be eventually replaced as we learn more about what time is, what other dimensions might be, etc. But for now we use it because it is useful. We can make predictions using this concept which we can verify.
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I don't think that is correct.   I assume you mean fourth spatial dimension, rather than the Minkowski 3 space, 1 time geometry of relativity.  For that, time is actually a dimension, and the question pretty much answers itself.\n\nThe best insight into a spatial fourth dimension is to read the delightful classic little book, "Flatland". Almost any library or bookstore should have it. It works on the analogy of an individual who lives in a two dimensional world - his name is "A. Square" - who learns about three dimensions.\n\nAnother way to insight would be to look up "tesseract" on a search engine. Aside from hits on Madalyn L'engel's misuse of the term in her children's boooks (avoid her description), you should find many discussions on how to represent simple four dimensional objects in three dimensions, just as we represent three dimensional objects on a flat piece of paper with perspective.\n\nFour dimensions would have two directions that are perpendicular to our three dimensional world. They have been given the names "ana" for four dimensional "up" and "kata" for four dimensional "down" with respect to our space. Of course these are just the Greek words for up and down. \n\nSo borrowing a description from Flatland, if a four dimensional sphere were to start anawards of our world and move through it in the kata direction, what we would see, as it intersected our world woild be first a tiny three dimensional sphere (cross section of the four dimensional sphere near its kata pole) which grows in size to a maximum (the "equator" passing through), and then decreases gradually again to its mini size before vanishing, having passed commpletely through our world and out the other side.
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Well, its been theorised that what is beyond the universe is a fourth dimensional bowl. Basically our universe is a 3d soup encased in a four dimensional bowl. How was that made? I would think the same way that our universe was created. I mean, we have only just begun to comprehend the world around us, many of the theories that are coming out are exactly that theories because we really dont know. Untill we can explore more of our universe, we arent really going to know, and if its in a 4th dimension, we really wont know. But, what you could do, is look at some of the sources, and hopefully those will help.
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The Z, Y and X axis governs organisation and function of empty space in 3D. There is time (the fourth dimension) which determines its function as well.
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it the way the math worked out, there are supposedely either 11 or 26 dimensions. this math is way beyond me, but the theory is still unproven so they may be any number.
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Mathematically n dimensions can be described but our experience is only 3 dimensions So the properties of fourth dimensonal shapes can be mathematically described and a fourth dimensional quantity that is in units^4 can also be calculated\n\nThis is an argument that the 4th dimension is time. That cannot be the case when one considers the properties in 3d are L, L, and L One would immediately envisage that the 4th, 5th .... nth dimensions would also all be L\n\nA tesseract, the 4 dimensional equivalent to the 2 dimensional square and 3 dimensional cube, is not a time related object at all. Its 3D projection can be build and the objects equivalent of a 2D shadow seen easily. In 4-space it occupies L^4 units^4. Wikepedia has some interesting information and projections of a tesseract
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In normal 3-D space, a cube can be described by {(x,y,z) where 0<=x<=1, 0<=y<=1, 0<=z<=1}\n\nIn normal 4-D space, it's {(x,y,z,w) where 0<=x<=1, 0<=y<=1, 0<=z<=1, 0<=w<=1}\n\nIn n-space, an n-cube can be represented by all n-dimentional vectors where the nth coordinate lies in the closed interval [0, 1].
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Yeah, we can't even envision what a 5D world would be like (here I'm talking four coordinate and one spatial dimensions).  Seriously, can you seriously envision what the equivalent of a sphere would be in 5D?  All points equidistant from a given point, but we have no idea how to "view" it in our minds.  However, we can use definitions and theorems to prove things about the other dimensions via differential geometry.  That's what is so incredible/awesome about math.\n\nBy the way, the 5D equivalent of a sphere (or 4D coordinate space equivalent) is called a hypersphere.  Go figure....
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We observe four dimensions everyday, three spatial and time.\nTime is called a dimension because it makes mathematical sense to do so. \nBut...theories such as string theory predict that the space we live in has in fact many more dimensions (frequently 10, 11 or 26), but that the universe measured along these additional dimensions is subatomic in size. As a result, we perceive only the three spatial dimensions that have macroscopic size.\n\nThis is not so strange as it sounds, which I'll show with an example. Imagine you are in an airplane, flying over sea. Seen from a height, the sea looks flat, two-dimensional. But when the plane looses height we start to perceive the waves, that move in a third direction we could see before.\n\nThe universe could be the same. Four macroscopic dimensions and a few more, hidden ones. We can only perceive them for instance, by the small effects their existence might have on subatomic particles.\n\nSerious enough?\nThe reference is a general article on the mathematical notion of dimensions, that contains links.
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from what i remember 4d is when you can see behind a person as your seeing their front (back and front of their head) and 5d is someway similair to 4d but in water...i think its related to water...
585241
the sensors we have in our body are only able to detect the 3 dimensions that we see. some physicists think that there are up to...11? dimensions existing, however we are unable to detect them and therefore...its not possible to "go" there. the same as we are not able to "go" into a 2D world...unless someone has figured out a way to become flat
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Scientist belive there are several dimesions.  Remember dimensions are based on measurement.  Length width height, 3 dimesions so we are in the third dimension.  A showdow for example only has length and width so it is the 2nd dimseion.  We cannot comprehend other demensions because we live in a 3d world where only LWH exist.  It is like asking your shadow what is tall, he would know because he lives in the 2nd demsiond.  So there are other dimensions yes and we can dicipher them though the wonders of mathmatics and physics.\n\nGravity works likes a bowling ball on a bed.  Think of the bed as the fabric of space.  If you put a tennis ball on the bed it would "gravitate" towards the bowling ball.  This is the theory of realtivity.  A worm hole forms when a really heavy mass punches through that space fabric.  If you had a million pound bowling ball it would go right though the bed.  The same things happens in space that heavy mass punches right though to the other side forming a worm hole.
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We live in a universe of observable/measurable quantities. For example, length, width, height, time, mass, etc.  If different quantities cannot be expressed in terms of the other quantities, they are "orthogonal" to each other - you can think of them as being separate dimensions. For example, on an X-Y graph, the x-dimension is independent of the y-dimension because you cannot express a "y" quantity as a combination of "x" quantities. \n\nSpace has 3 dimensions (length, width, height); time is a fourth dimension that cannot be expressed in terms of the other three.\n\nAn n-dimensional space is just a space that is characterized by "n" orthogonal quantities - quantities that cannot be expressed in terms of each other. To completely define the space/universe, you only need to specify "n" values - any more than that would be superfluous because the other values would be some combination of the other orthogonal quantities.\n\nExample: if we lived in a 4-dimensional space characterized by length, width, height, and time, all you need to do is specify those 4 quantities to uniquely determine any point in that space.  If we add another quantity (such as temperature) that cannot be expressed in terms of the other 4, we now have a 5-dimensional space that requires 5 quantities to be specified.