I [Quantum Computing] Quantum Parallelism State Calculation

llha
Messages
4
Reaction score
1
TL;DR Summary
Nielsen and Chuang state calculation isn't the full tensor product? But a full tensor product would be useless to measure?
Hi, I'm going through Nielsen and Chuang's Quantum Computation and Quantum Information textbook and I don't really understand this part about quantum parallelism:
1626469417681.png


Shouldn't the resulting state be (1/sqrt(2^4)) * (|0, f(0)> + |0, f(1)> + |1, f(1)> + |1, f(0)>), since the resulting state would be the (normalized) tensor product of (1/sqrt(2)) * (|0> + |1>) and (1/sqrt(2)) * (|f(0)> + f(1)>)?

I understand that would be pretty useless to measure, so I know I'm wrong, but I don't understand where I'm going wrong. Thanks in advance.
 
Physics news on Phys.org
A state of two qubits can be written in the base ##\left|00\right>, \left|01\right>, \left|10\right>, \left|11\right>##. I would recommend you to apply the operator over these 4 states such that you really understand how the operator works, after that you can write the initial state as a linear combination of those states and use linearity and the previous result to get the final state.
 
Not an expert in QM. AFAIK, Schrödinger's equation is quite different from the classical wave equation. The former is an equation for the dynamics of the state of a (quantum?) system, the latter is an equation for the dynamics of a (classical) degree of freedom. As a matter of fact, Schrödinger's equation is first order in time derivatives, while the classical wave equation is second order. But, AFAIK, Schrödinger's equation is a wave equation; only its interpretation makes it non-classical...
I am not sure if this falls under classical physics or quantum physics or somewhere else (so feel free to put it in the right section), but is there any micro state of the universe one can think of which if evolved under the current laws of nature, inevitably results in outcomes such as a table levitating? That example is just a random one I decided to choose but I'm really asking about any event that would seem like a "miracle" to the ordinary person (i.e. any event that doesn't seem to...
Back
Top