This is a discussion on Applications of Quantum physics/Quantum Mechanics? within the Science and Technology forums, part of the Topics of Interest category; Originally Posted by an absurd man Why would classical speeds be an issue? If it can someday transfer bulk bulk ...
Actually I'm fairly sure quantum mechanics is somewhat statistical.
Wave functions break down into probabilistic representations of the thing you want to know more about.
With wave functions, you use things on them called operators. For example, if you want to know about the position of a particle in a confined quantum system, you use the position operator. Essentially you perform some operation on the mathematical wave function, which changes the function so it then describes the thing you want to know about.
In the case of using the position operator, you're left with a function that describes the probability of the particle being in a certain place.
This image may or may not help: (EDIT: Didn't realise the image was actually a GIF. Awesome!)
It's the double-slit experiment, the one where light comes through two slits then the waves interact with each other, causing light and dark fringes on the screen.
By mathematically modelling the photons entering the two slits as a quantum physical system, you can use the position operator and will find a wave function that looks like that shown at the top of the image.
The wave function, as a probability function, is saying simply that there is a greater likelihood of photons hitting the screen at the points where the function has a higher value - where there is a higher probability of the photons landing there. So the peaks in the wave function are the light fringes, and the troughs of the wave function are the dark fringes (since the probability approaches zero).
What this is saying is that statistically you can expect the photons to land in those positions. You can't know for sure, but the wave function, as a probability function, describes it in that way.
"It is most probable that the photons will land on the screen in that way, and statistically we can verify this is the case."
Of course, QM is pretty darn statistical. Your observables are described by the expectation values (stats!), while the normalization of WF's and uncertainty (std. deviation from stats!) is pretty darn useful.
I realize my not equals sign must have been heavily misinterpreted. What I meant was that all QM is statistical, but not all statistics is QM. That biophysical systems are not necessarily quantum systems if they are governed by statistical laws; or rather, if we interpret them as such.
As far as I know from my QM course and Griffiths, you cannot "violate" the uncertainty principle in QM. That's kind of like talking about the applications of Newtonian dynamics and saying something violates Newton's second law. Uncertainty principle means that you cannot measure the state of a particle without collapsing it to one of the possible states. For instance, if the information was encoded by up or down spins on magnetic chips, one would measure a spin up or spin down, but not both, on a single electron (unless you get into weird quantum entanglement things, feel free to research it, some people claim it could lead to faster than light information transfer and therefore make this type of stuff possible- Superluminal communication - Wikipedia, the free encyclopedia ). This article is saying that there is no way to copy quantum information (a.k.a. reproduce a state of the system) and not violate the uncertainty principle at the same time. Here's the actual journal article, which talks about wanting to "avoid grandfather-like paradoxes", i.e. violating fundamental quantum mechanics principles. http://www.imsc.res.in/~aqis13/exten...dd_Brun_48.pdf Specific quote about this:i.e. without breaking quantum mechanics, let's make a conceptual/mathematical formulation where we take continuous measurements of the system and set up an algorithm to copy information. Then maybe, hypothetically, we could have something that would loop through these states. Theoretically.If one views a density operator as a statistical ensemble or as a state of knowledge, then Deutsch already realized that his model still leads to grandfather-like paradoxes... However, if one considers a density operator to be the fundamental object which characterizes a quantum state, then Deutsch’s model indeed resolves these paradoxes.
The transistor wasnt even possible without some of the early theories and such of quantum mechanics. So yes, it does have applications. The fact that quantum computers are now in use proves such.
Also, quantum computers have nothing to do with transistors (most of them don't use transistors) and are for all intents and purposes not in use... quantum computing is still very primitive. The largest quantum computers have around 500 qubits, and are not really useful for anything besides scientific experimentation for studying them. And as for what we've achieved with quantum computing.. the largest integer factored through quantum algorithms is 143. But quantum computing does have potential for the future, if we manage to build much larger quantum computers.