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| bio | website | |
|---|---|---|
| location | New York | |
| age | ||
| visits | member for | 1 year, 7 months |
| seen | Dec 12 '11 at 0:52 | |
| stats | profile views | 22 |
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Nov 1 |
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why evaluate at lambda = 0 hmm... yeah i guess this is just a mathematical thing you can't really draw a picture |
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Nov 1 |
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why evaluate at lambda = 0 this is analgous to choosing a vector with a tail at the origin in 3-d euclidean space? thx |
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Nov 1 |
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why evaluate at lambda = 0 thanks david... i'm wondering why the interval is [0.1]? but this is helpful |
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Oct 31 |
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Understanding pregnancy length and life time based on dimension analysis and order of magnitude estimation @RichardTerrett funny you mention that considering I made no mention of how an eye works and only discussed length scales in my post... keep up the good chemistry bro. |
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Oct 30 |
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why is time order invariant in timelike interval? i don't understand this diagram at all... |
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Oct 30 |
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Understanding pregnancy length and life time based on dimension analysis and order of magnitude estimation np, this question isn't so bad... not sure why it's getting voted down... one problem is that these questions are almost certainly availble just by googling as they are pretty standard questions. though 2 is actually a very intrigueing problem i'd like to see someone tackle that one. |
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Oct 30 |
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Understanding pregnancy length and life time based on dimension analysis and order of magnitude estimation 10,000 is an integer number of colors that need to be distinguished (divisions in which the .02cm eye needs to be broken up into in a sense). that has nothing to do with length. I love your attitude though : ) |
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Oct 30 |
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why is time order invariant in timelike interval? perhaps I do not understand what is meant by "rotating a point". is the problem. about what axis? |
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Oct 30 |
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why is time order invariant in timelike interval? ron i'm a little confused... I understand the concept of a circle and I believe that indeed that is the equation for a hyperbola... what I do not understand is what you mean by "rotate a point continuously cannot move points from the upper hyperbola to the lower hyperbola" . to rotate a point on the circle you just spin it... how can you rotate a point on a hyperbola? |
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Oct 30 |
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why is time order invariant in timelike interval? in this sense time-order is associated with the plus or minus sign of t. interesting thanks, david... ron's answer is a little over my head... I need to look at that some more... |
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Oct 30 |
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why is time order invariant in timelike interval? this one is helping somewhat ... physics.stackexchange.com/questions/12435/… |
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Oct 28 |
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inverted Harmonic oscillator as an aside question, can we think of this in terms of Forces. normally a harmonic oscillator drives the particle back to where it was, whereas this force would drive the particle away from where it is faster and faster... seems like the energy would diverge very quickly, but still are there not quantized solutions?? -- oops i see lubos has given those explicitly is there any further information on this subject of interest? |
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Oct 24 |
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understanding why inversion cannot be accomplished by a rigid change heh ok... you right |
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Oct 24 |
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understanding why inversion cannot be accomplished by a rigid change yo ron... what if you cut out some of the fabric from the glove and then repatch it? what is the mathematical term for that? |
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Oct 24 |
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understanding why inversion cannot be accomplished by a rigid change yo ron... can you point me to a discussion of how 3-d objects ( or higher dimensional objects behave under inversion etc)? |
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Oct 24 |
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understanding why inversion cannot be accomplished by a rigid change yo ron thx for the tip! as a further point I see also you cannot turn a left-handed glove into a right handed glove by a translation and a rotation. |
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Oct 24 |
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understanding why inversion cannot be accomplished by a rigid change first we know the improper rotation changes the handedness of the coordinate system. now, imagine a rigid body rotating about the origin. say there are initially some right handed set of coordinates fixed in the rigid body frame at t=0, and then we start rotating the rigid body about the origin of this coordinate system. There is simply not way you can rotate such that the handedness will change!! the rotation of a rigid body is completely defined by the euler angles and if you imagine any of these 3 rotations, there is no way to actually invert invert the axis by such a rotation. |
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Oct 24 |
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understanding why inversion cannot be accomplished by a rigid change an inversion is like a plane-reflection of a rigid body... without a rotation ( thus the handedness get's changed right?) |
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Oct 24 |
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understanding why inversion cannot be accomplished by a rigid change that has to do with certain molecules doing wierd quantum things ( NH3 does this supposedly) but I don't want to get into all that. supposedly NH3 can tunnel into it's left-handed state or something (i don't understand it classically so I'm not too sure) |
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Oct 24 |
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understanding why inversion cannot be accomplished by a rigid change if you look at the vector r = (1,0,0) maybe there is a way to explaon this with a simple example like that, i'm workin' on it right now... |
