Lasik Surgery: When the Fine Print Applies to You
By ABBY ELLIN
Published: March 13, 2008
After undergoing Lasik sugery, most patients are quite satistfied. But all surgery carries a risk.
Thursday, March 13, 2008
Sunday, March 9, 2008
Relative harm of various drugs!
Yes - Alcohol is #5 on the list compared to LSD, cannabis or ecstasy!
Thursday, March 6, 2008
Why complex vector space inner product is defined with conjugate symmetry?
If you don't use conjugate but simple symmetry it will produce a contradiction with the axiom X . X >= 0
assume X.Y = Y. X
X.X >=0
=> c1 X . c1 X >= 0 [where c1 is a complex number with an imaginary part]
=> c1 (c1 X . X) > = 0 by linearity
=> c1 (X . c1 X) > = 0 by symmetry
=> c1 . (c1 ( X. X) )>= 0 by linearity
=> (c1 . c1) . (X.X) > = 0 by associativity of complex numbers
which is a contradiction.
to see this, if you take c1 = i [square root of -1]
=> -1 (X.X) >= 0
=> (X.X) <= 0
cool, right?
assume X.Y = Y. X
X.X >=0
=> c1 X . c1 X >= 0 [where c1 is a complex number with an imaginary part]
=> c1 (c1 X . X) > = 0 by linearity
=> c1 (X . c1 X) > = 0 by symmetry
=> c1 . (c1 ( X. X) )>= 0 by linearity
=> (c1 . c1) . (X.X) > = 0 by associativity of complex numbers
which is a contradiction.
to see this, if you take c1 = i [square root of -1]
=> -1 (X.X) >= 0
=> (X.X) <= 0
cool, right?
Tuesday, March 4, 2008
Sunday, March 2, 2008
Evolution videos in Google videos
There are nice set of videos in Google videos about Evolution - MUST see:
PBS Nova Evolution Episode number three (3), maned "Extinction" Documentary. (3rd out of 7)
Tuesday, February 5, 2008
Monday, February 4, 2008
helicopter costs 18M dollars!
Didn't know helicopter is this expensive!
http://en.wikipedia.org/wiki/AH-64_Apache
http://en.wikipedia.org/wiki/AH-64_Apache
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