Re: PHYS; Quantum Teleportation

Wayne Hayes (wayne@cs.toronto.edu)
Sat, 13 Dec 1997 12:51:39 -0500


Anders Sandberg <asa@nada.kth.se> wrote:
>>> An MRI scanner will change the quantum state of your brain and thus it will
>>> change you, so will reading this post or being bitten by a mosquito.
>>
>> Dr. Chao is this correct?

>Yes, it is correct. A MRI scan makes most of your hydrogen atom nuclei
>align their spins, and then electromagnetic fields twist them around
>so that they emit telltale radiation. Very elegant, and quite dramatic
>on the quantum level.

Right. So, to be clear, the first line of the first quote is correct,
but the second is *not*. An MRI makes dramatic changes on the quantum
level, but absolutely *no* detectable change in the personality,
memory, etc., of the individual. Thus, the spin state of the hydrogen
atoms in your brain is absolutely irrelevant to the health and welfare
of your mind, and thus, need not be duplicated by a teleportation
device.