From: ram@zedat.fu-berlin.de   
      
   In the third lecture of the series "New Revolutions in   
     Particle Physics: Basic Concepts" (Fall, 2009) from "The   
     Theoretical Minimum", Professor Susskind talks about what   
     a quantum field is and how it is related to particles.   
      
     He considers a circle with a coordinate "x" and an amplitude   
     "exp( i k x )", and says that the momentum "p" is "hbar k".   
      
     Then he says (about 8 or 9 minutes into the video):   
      
   |"k" is called the "wave number". Uh. It's a wave number.   
   |And it can be positive or negative? Waves moving to the left,   
   |moving to the right, corresponding to momenta, going to the   
   |left or the right.   
      
     How can he talk about "waves moving to the left" if his   
     amplitude "exp( i k x )" does not depend on the time   
     (contains no "t")?   
      
     Do you think that "exp( i k x )" without "t" in his model   
     means that the amplitudes are constant (not depending on   
     the time) or is "exp( i k x )" a snapshot of the situation   
     taken at one instant (but actually depending on the time)?   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)