Naked Science Forum

Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: parakorn on 25/12/2014 04:40:18

Title: Does the Quantum computer can send the information faster than light ???
Post by: parakorn on 25/12/2014 04:40:18
The quantum computer that use the concept from EPR paradox. Does it can transmit information faster than light.Does this mean that the special relativity wrong.Who can explain this for me please
Title: Re: Does the Quantum computer can send the information faster than light ???
Post by: PmbPhy on 25/12/2014 05:15:39
Quote from: parakorn
The quantum computer that use the concept from EPR paradox.
To be precise, they use quantum entanglement.

Quote from: parakorn
Does it can transmit information faster than light.
No. Quantum entanglement cannot be used to transmit information faster than the speed of light.

Quote from: parakorn
Does this mean that the special relativity wrong.Who can explain this for me please
Since quantum entanglement can't  be used like that then the answer to your question is no.
Title: Re: Does the Quantum computer can send the information faster than light ???
Post by: yor_on on 01/01/2015 11:55:23
You can change it slightly if you like.

Are there computations possible for a quantum computer that would take a infinite, or near infinite, time for a ordinary digital computer, or human, to make? Further, is there a difference to the time a quantum computer needs to compute a answer, depending on complexity of the question? If not, why?
Title: Re: Does the Quantum computer can send the information faster than light ???
Post by: dlorde on 01/01/2015 14:23:13
You can change it slightly if you like.

Are there computations possible for a quantum computer that would take a infinite, or near infinite, time for a ordinary digital computer, or human, to make? ...
There is no such thing as 'near infinite'. [/pedant]
Title: Re: Does the Quantum computer can send the information faster than light ???
Post by: Bill S on 01/01/2015 16:14:58
Quote from: Pete
Quantum entanglement cannot be used to transmit information faster than the speed of light.

Obviously, this statement is true, at least within the context of our current knowledge, but how important is the word "used"?

Does the fact that we cannot access any information from a ftl situation necessarily mean that no information is actually passed?

Someone will probably argue about the definition of "information", but it seems reasonable to think that if B is influenced by something that happened to A, then information must pass between A and B to make this possible.

BTW, this whole scenario is simply explained in my theory of infinity; but I'm mot going to muddy the waters with that here.  [:)]
Title: Re: Does the Quantum computer can send the information faster than light ???
Post by: jeffreyH on 01/01/2015 17:22:05
Information is an observer dependent term. If we consider the whole universe to be the observer then flt information is possible. That is from one part of this hypothetical observer to the other. It all depends upon how acceptable the notion of the whole universe as the observer is and what a definition of observer should contain.
Title: Re: Does the Quantum computer can send the information faster than light ???
Post by: dlorde on 01/01/2015 19:09:02
Whether anything (e.g. state correlation) is communicated FTL depends on the interpretation you choose. For example, the Many Worlds interpretation doesn't have this issue.
Title: Re: Does the Quantum computer can send the information faster than light ???
Post by: evan_au on 01/01/2015 20:53:42
Quote
Are there computations possible for a quantum computer that would take a [very long] time for a ordinary digital computer, or human, to make?
Quantum computers (http://en.wikipedia.org/wiki/Quantum_computing) work by a superposition of states.

In theory, a quantum computer with just 80 qubits could do calculations that would strain a silicon computer the size of the Earth, because the Eath does not contain 280 atoms.
In practice, qubits are very unstable, and need to be kept in carefully controlled conditions or the qubits will suffer "decoherence". The most dramatic published result from 2011 was from a 4-qubit quantum computer which proved that 143=11x13.

Quantum computers are a subject of active research around the world; Edward Snowden claimed that the NSA were investing a lot of money in quantum computing for their potential to crack encryption. Again, in theory, a quantum computer can try out many passwords at once.
Title: Re: Does the Quantum computer can send the information faster than light ???
Post by: Bill S on 01/01/2015 23:00:27
Quote
There is no such thing as 'near infinite'.

Dlorde, that is most certainly not pedantic.  It is fundamental to the understanding of infinity.
Title: Re: Does the Quantum computer can send the information faster than light ???
Post by: yor_on on 02/01/2015 10:08:28
near infinite is indeed meaningless :) But we use it. We also use 'infinite' without ever being there. This universe is a 'finite' thing in forms of 'emergences', at least measurably. That doesn't mean that infinite doesn't exist, and if you assume this to exist one better define why one won't get 'near' it :)

the question I wanted to ask is whether we, by assuming that complexity has nothing to do with the 'instantness' of a answer, could decipher a answer to what a arrow is, as contrasted to the 'mathematical space' in where a quantum computer is assumed to find that answer.