aparent
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It is a bit more complicated then that. The only penalty to time is a constant factor if you are willing to use space proportional to the computation time. I did a bit of work on how to do time-space trade-offs in reversible circuits in my masters thesis
http://hdl.handle.net/10012/10949.
>seems for just a second like a normal, intuitive process that's just been obscured through poor explanation--then you learn a little more and realize it's far more bizarre than you'd imagined.
This is a great explanation of the process of learning about quantum mechanics.
A good test once you start to think you have figured things out is to check how your own conceptual model deals with Bell violations or experiments like: https://en.wikipedia.org/wiki/Quantum_eraser_experiment
Both ends of the experiment share entangled photons produced from a single source and sent both ways. The sender performs some operations and measurements on their two photons, i.e. the photon they wish to send, and their entangled photon. They then send the result of the measurements to the receiver (this can be done any normal way you can think of; for example over a classical network).
The receiver does some operation on their entangled photon based on the results of the senders measurements. After these operations their entangled photon will be in the exact same state as the sent photon.
So to answer your question, information is transmitted classically but that information would not be enough without the use of entanglement.
Quantum teleportation requires classical communication from the sender to the receiver of the state. Whether the teleportation itself happens faster then the speed of light is up to your interpretation of Quantum mechanics. The important part is that it does not allow information (classical or quantum) to be transmitted faster then light.
You are mostly correct. In fact the key strength of something like AES is realistically not even going to be reduced by half. In terms of the query complexity (the number of calls to AES that are needed) using Grover's algorithm the key strength is half what it would be with classical brute force. In practice though these queries must be implemented as quantum circuits and run a on quantum computer which adds a pretty large overhead.
This article is about the implementation of an asymmetric protocol based on the RLWE (https://en.wikipedia.org/wiki/Ring_Learning_with_Errors) problem.
>I think LSD should be illegal
Out of interest, why do you think this?
http://www.ncbi.nlm.nih.gov/pubmed/16571087"Thus, collectively the findings provide little evidence that in euthyroid, iodine-replete individuals, soy foods, or isoflavones adversely affect thyroid function. In contrast, some evidence suggests that soy foods, by inhibiting absorption, may increase the dose of thyroid hormone required by hypothyroid patients. However, hypothyroid adults need not avoid soy foods. In addition, there remains a theoretical concern based on in vitro and animal data that in individuals with compromised thyroid function and/or whose iodine intake is marginal soy foods may increase risk of developing clinical hypothyroidism. Therefore, it is important for soy food consumers to make sure their intake of iodine is adequate."
A small addition to noondip's reply:
"Clinical studies show no effects of soy protein or isoflavones on reproductive hormones in men: results of a meta-analysis."
https://www.ncbi.nlm.nih.gov/pubmed/19524224
Also you say that you have not seen enough studies to rule these out; what studies have you seen to make you believe they might be an issue?
This comes from deceleration of the capsule due to air resistance as it enters the atmosphere.
It is so good that even Alice can't decrypt those with confidence! :)
> Asymmetric crypto clearly is in NPcomplete
To be in NP-complete a problem must both be in NP and every problem in NP must have a polynomial time reduction to it.
This means that NP-complete is fully contained in NP and in fact smaller if P!=NP.
For example P is contained in NP and if P!=NP then no problems in P are in NP-complete.
I think the issue is that the additional properties required for asymmetric key cryptography (as opposed to symmetric) are hard to gain without introducing some structure.
What do mean by this? I don't think complexity classes give any provable security to asymmetric cryptography. It cannot be proven that the difficulty of breaking any of the currently used (or known?) asymmetric key cryptography is not in P (It can't even be proven to be NP-complete).