What is a dimension? In 3D...and 2D... and 1D
1D - it's the new 3D! Tweet it - http://bit.ly/mP3FFo Facebook it - http://on.fb.me/qtTraR minutephysics is now on Google+ - http://bit.ly/qzEwc6 And facebook - http://facebook.com/minutep...
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How do we know we live in three dimensions? Here's a clue: it's not just that we haveto use three coordinates (like x,y,z, or latitude, longitude, altitude) to label every pointin space - because we don't!Mathematicians have showed that it's possible to fill up 2d or 3d space using a one-dimensional"space-filling" curve - that means that every point in 3d space can be labelled using justone coordinate: our position along the curve! (it also means that a square and its sidecontain the same number of points - crazy, right?)So how do we know that we live in three-dimensional space and not on a one-dimensional line curledup so much that it looks three-dimensional? Well, the short answer is that we don't know– but we...
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How do we know we live in three dimensions? Here's a clue: it's not just that we haveto use three coordinates (like x,y,z, or latitude, longitude, altitude) to label every pointin space - because we don't!Mathematicians have showed that it's possible to fill up 2d or 3d space using a one-dimensional"space-filling" curve - that means that every point in 3d space can be labelled using justone coordinate: our position along the curve! (it also means that a square and its sidecontain the same number of points - crazy, right?)So how do we know that we live in three-dimensional space and not on a one-dimensional line curledup so much that it looks three-dimensional? Well, the short answer is that we don't know– but we...
