Quantum teleportation

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The quantum teleportation is based on the quantum Entanglement; Imagine two particles, like two photons. They interact in a point and their function states create a single function state.

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The first particle is then analyzed in a lab, called lab A. And the second one in lab B; an experiment accomplished on the first particle will change its function state and its behaviour it's going to be appreciate also on the second particle. They receive the same perturbation, even if the distance between them. The measurement on the first, will define instantly the state of B.  But, in this phenomena there isn't migration of information.

However, Imagine a third particle, called particle C; It interacts with partcle A (Which is entangled to B), the result is then trasmitted (Via radio or optic fiber) to lab B. In lab B, a scientist could reply the state of C on another particle C' ( of the same type of C, a photon for example) which is not C. The final particle is not the initial one, but has its same quantum state. It's created a copy of the C particle; the information is teleported but not the matter!

To be clear : If i want to being teleported somewhere else from my actual position, I need an ordered configuration of matter which is exactly the same as mine on the other side. My information will be trasmitted, but not the matter with which I am made.

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Posted (edited)
1 hour ago, Heis3nberg said:

To be clear : If i want to being teleported somewhere else from my actual position, I need an ordered configuration of matter which is exactly the same as mine on the other side. My information will be trasmitted, but not the matter with which I am made.

How many particles is in your body? How many information can be send per second? Therefore, how long it will take to send all your state from B to A, or A to B?

If somebody is able to do what you described, instead of teleportation, could make backup of himself or herself at exact date, and if accident happened and/or died, recreate body from backup..

If somebody is able to do what you described could run computer program analysing backed up data of the body to find cancer, mutation, anomalies, illness etc.

Edited by Sensei
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55 minutes ago, Heis3nberg said:

a scientist could reply the state of C on another particle C' ( of the same type of C, a photon for example) which is not C.

Impossible:

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18 hours ago, joigus said:

You are right, but the quantum teleportation respects the no-cloning theory; In fact it's possible trasmitting the information from a state to another, if the information of the initial state is destroyed. The experiments have proved the teleportation using virtual photons.

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There is not such a thing as no-cloning theory. The non-cloning theorem is the simple fact that if quantum evolution is linear, there is no way that you can produce, as a result of an interaction, an outgoing state for a second system that consists in the second quantum system cloning (xeroxing, carbon-copying, reading, reproducing) the first system's quantum state. This is not a requisite of quantum teleportation (biggest misnomer in physic's history), but a requisite of your setup.

More schematically than the Wikipedia article:

$\left|a\right\rangle \left|\psi\right\rangle \rightarrow\left|a\right\rangle \left|a\right\rangle$

$\left|b\right\rangle \left|\psi\right\rangle \rightarrow\left|b\right\rangle \left|b\right\rangle$

But, on account of linearity of quantum evolution:

$\left(\left|a\right\rangle +\left|b\right\rangle \right)\left|\psi\right\rangle \rightarrow\left|a\right\rangle \left|a\right\rangle +\left|b\right\rangle \left|b\right\rangle$

But:

$\left(\left|a\right\rangle +\left|b\right\rangle \right)\left|\psi\right\rangle \rightarrow\left(\left|a\right\rangle +\left|b\right\rangle \right)\left(\left|a\right\rangle +\left|b\right\rangle \right)$

which does not coincide with the first expression. So cloning quantum states is impossible if quantum evolution is linear.

Maybe you can relax the hypotheses. The most natural one is assuming that the state to be copied is a strict mixture (a statistical 'scrambling' of several wave functions). But a similar result holds: The no-broadcasting theorem.

Again, it's not a consequence of EPR correlations, but a consequence of the general principles of quantum mechanics. You cannot broadcast in any way a quantum state.

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Posted (edited)
1 hour ago, joigus said:

But:

$\left(\left|a\right\rangle +\left|b\right\rangle \right)\left|\psi\right\rangle \rightarrow\left(\left|a\right\rangle +\left|b\right\rangle \right)\left(\left|a\right\rangle +\left|b\right\rangle \right)$

which does not coincide with the first expression. So cloning quantum states is impossible if quantum evolution is linear.

Sorry, I didn't explain. This would be cloning for quantum superposition $$\left|a\right\rangle +\left|b\right\rangle$$.

Edited by joigus
latexing inline

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