FTP, name this quantum mechanical concept which denies the possibility of simultaneous arbitrarily precise measurements.
It can be demonstrated by representing a partical as a Gaussian wavepacket and taking its Fourier transform.  In position and wavenumber space, the packet widths are inversely correlated, so that a well-defined wavenumber implies an ill-defined position.  FTP, name this quantum mechanical concept which denies the possibility of simultaneous arbitrarily precise measurements.
It can be demonstrated by representing a partical as a Gaussian wavepacket and taking its Fourier transform.  
Heisenberg uncertainty principle