Quantum computing Definition and 253 Threads

I'm not physicist, but a software developer. Please don’t hang up.:smile: I am building massive multiplayer online game server, and I started building it from scratch. I found that some programming issues emerged from it which had striking resemblance to quantum quirkiness, so I just wanted to...

[I've searched for posts on this issue, but haven't found anything quite specific.] By 'real' I mean something you might actually buy in, say, 2015 and actually performs those pesky problems that involve an infinity of potential solutions. If a quantum entity actually does have definite...

Hey guys a friend of mine found this article about the world's first commercially available quantum computer. "[URL I remain slightly skeptical given controversy and criticism surround D-wave in the past. http://en.wikipedia.org/wiki/D-Wave_Systems#Criticism" So I was hoping members of...

More recent book than Nielsen and Chuang "Quantum Computation and Quantum Informaion" For this famous book, I discovered too late that there are no References more recent than 2000. Do you know of a textbook that covers more recent developments in Quantum Computing? Thanks Don Parsons

In a standard quantum computer, the computing machinery is kept in a superposition of states, with each state doing the computation on different data. It's like having the superposition of a bunch of cats in a box with each cat doing a calculation on different data. The more complex the cat...

Ok guys so I know you don't like us quantum chemists and the approximate methods I'm about to talk about isn't "really physics" but I am looking for some good answers and if you guys have anything to offer BEYOND HYDROGEN then perhaps you can assist me. I am wondering if someone can explain...

So I've just finished my first year of mechanical engineering in Australia (pretty generic subjects) and now is the time i need to make sure I am doing the right major. I've been quite sure throughout the year that mechanical is what I want to do however after doing my first unit of electrical...

Hi, after reading this article, I was left wondering how the heck a quantum computer can be simulated. To begin with, how is a quantum computer of 42 qubits built up? And the how could this computer possibly be simulated? I mean, the wave function of one qubit is a three dimensional scalar...

When will quantum computers become useful? For example, cracking some real-world encryption, simulating quantum behaviour of molecules, or enhancing web search engines? I somehow have the impression that this is a field of physics where theorists keep dreaming and experimentalists keep playing...

Hi, I'm a second year physics major with specialization in computational physics, and I have recently become interested in quantum computing, and stuff dealing with computers like the memory cell nanoribbons made of graphene. I wanted know if I am currently pursing the best degree to get...

I was curious if it would be possible to construct an incredibly simple and most likely trivial computer based on an interferometer style setup which could generate random numbers based on the quantum mechanical nature of light. Namely, with a basic laser pointer, some mirrors, and a beam...

I was curious if it would be possible to construct an incredibly simple and most likely trivial computer based on an interferometer style setup which could generate random numbers based on the quantum mechanical nature of light. Namely, with a basic laser pointer, some mirrors, and a beam...

Hi All, we hear about this term quantum computers and electronics which is currently under research. Will there be any major shift in our computer industry from semiconductor to quantum in next 5 years? Is there any significant advancement in this field? Just curious to know:)

Hi i just wanted to know what the main difference between quantum computers and normal computers are? Is it that a Qubit can be 1 and 0 at the same time... becaus that is what i found after i researched however my friend states that the quantum computer can run many different sets of code at...

Hi everyone I am working on entanglement between an atomic system and its spontaneous emission but I don't know how to connect this kind of entanglement with quantum computation, I have read in different articles that entanglement is somehow essential in applications like quantum communication...

Hello. Our current computers use bits, so they use the binary numeral system. But I heard that the future quantum computers will use qubits instead of simple bits. Since in the word "qubit" there is the word "bi" I first thought that this meant that quantum computers would use binary (base...

Hello, news : http://www.wired.com/2014/09/martinis/ Patrick

Hello, Physics Forums. I am a recent graduate from UCLA with a bachelors in chemistry. I would like to pursue a graduate degree in physics in (in order of preference) quantum computing, atomic physics, or nuclear physics. Right now I have four schools that I think are fairly safe but, my degree...

Hi, I'm entering graduate school this fall and was looking to improve my computational physics knowledge. I have experience with MATLAB, Python, Java, and some C. My question is which resources do you think are the best for learning the methods required for computational quantum...

If you haven't followed what this company has been doing, you probably don't understand my trepidations at posting about it here - but I do want to hear reaction to Professor Matthias Troyer test results from this sector of the Physics community. It involves "Engineering", "Quantum Physics"...

i can not say that I'm super good at knowing my quantum physics, but i know enough, and even if i don't i can just search it up! so, recently i have taken an interest into the quantum computer , and the theories of how it works, is there anywhere that talks about it?

How is an ancillary bit used in a logic gate? I looked at http://en.wikipedia.org/wiki/Ancilla_(quantum_computing ) as well as Quantum Computation and Quantum Information by Nielsen and Chuang, but neither source really explained how an ancillary bit is used (in a logic gate circuit) or...

Context: I am entering my Junior year in a computer engineering undergraduate program, and have not yet taken any course involving quantum physics. The only course I am required to take involving quantum physics is Semiconductor Device Physics. I am doing well academically, and am considering...

Does quantum computer can to send the information faster than light ?? I have read many of paper about quantum computer that come from quantum entanglement. The Quantum Entanglement may be use in Quantum computer.Does it can use to send the information faster than light or it can surpass the...

I did some quick searches and couldn't find any discussions on this topic. Anyone with background or ability to describe the basics to a novice. I understand the high level basic concepts, but don't know how information is encoded and how the qubits are operated on. Unlike boolean logic gates...

I want to do a PhD in Quantum Computing. Which universities in English-speaking countries have prominent research groups in this field? Most universities I checked have a Quantum Information group, and they usually mention the term "Quantum Computing" somewhere on their website, but it's not...

Ok so I'm reading up on quantum computers , and I want to ask some question to clear some things up. So in simple terms a quantum computer or the chip itself would have to be made of something , a enclosure somekind that can hold single particles seperated, that have spins (most common probably...

Can anyone suggest any? I have all of the coursework for a PhD, So I'm not afraid of anything but I will have lots of questions.

I've been reading about quantum entanglement, and I read in many websites that it plays a very important role on quantum computers. I tried to find why, but the only information I got was that quantum entanglement allowed us to see the value of a qubit without interacting directly with it (and...

I understood many maths of QM and even QFT.. but I can't totally understand how a quantum computer can factorize millions of times faster. In normal turing machine, there is 0 and 1. But in quantum computers, there is 0 and 1 and superpositions of it.. meaning it can be 0.0001 or 0.5253 or 0.874...

Next semester I am going to write a undergrad thesis about quantum computation, but my background is not from physics but from mathematics and computer engineering. In this talk http://www.youtube.com/watch?v=Rvn_3cCrl9c Andris Ambainis talks about how he got into the field of quantum computing...

LiveScience Quantum Computing Breakthrough QE for short. Please read that article. I need someone to set me straight here... Is QE a real thing, as in it's no longer an idea but is 100% a real thing. If two particles become entangled then whatever happens to one particle instantly...

How fast, exactly, is it hypothesized that quantum computers could feasibly reach? If an operation takes 1 second on an average modern-day computer, how long will it take a quantum computer, using an upper-bound idea for the speed these machines could one day reach?

Homework Statement q1]] Which of the following pairs of quantum gates commute? Select all that apply. (Gates A and B commute if and only if for any input applying A and then B gives the same results as applying B and then A. This is the same as saying that the unitary transformations commute.)...

I've heard it claimed before that brains could be quantum computers (I think it was on Through the Wormhole). Is there any evidence of this? I'm thinking about reading up on quantum computation, but don't know anything about quantum mechanics yet. I'm mostly interested in machine learning...

how is it that we are able to get atoms to work like bits? and what is their counting system? because simply counting in 1's and 0's doesn't seem to make so much sense when electrons can be doing any number of things when they are not being observed. i recently watched this but it didnt...

I have been reading about physicists that study things like computational neuroscience/AI and quantum computing. It is my understanding that these subjects are very closely linked and form a relatively new and open area of science research. I also have the impression that a physics degree is the...

Hi, Not sure if this is the right place to post this but... I understand that D-Wave has a developed an adiabetic quantum computer. Google and Lockheed Martin have both purchased these computers from D-Wave recently. Could such a quantum computer (or perhaps future versions of it with...

I was thinking whether I should put this threat under general physics or engineering... but anyway, here's the problem: how long do we need to wait until quantum computing is put to use? Also, can programmes that run on classical computers run on quantum computers, or do they need an entirely...

What will the technological impact of Quantum Computing be? What meaningful benefits will Quantum Computing bring humanity? What will be the order of progression of its impact? How will Quantum Computing advance our technological growth curve? Where will the money in Quantum Computing be...

I am very interested in Quantum Computing but I am worried about getting a job, making it into a good university to do post grad etc. Do I need to do computer science to work in quantum computing research and development? I like computers but I don't like studying it, I have textbooks of...

Hi This is help from lectures on quantum computing that I missed due to illness and now my professor is away. 1) Can anyone help me on what a function gate is and its matrix representation? I realize that the function is not something like x^2 but something that takes a value from 0 or...

I have never—and I really do mean never—seen an article in the mainstream press about quantum computing that didn't get it completely wrong. I don't just mean "over simplified"—physics is highly technical and ignoring important details for lay audiences is just a fact of life. I mean that they...

Homework Statement Show that three controlled-NOT gates (for a 2 qubit system) can be combined to form a SWAP gate. The control qubit alternates between the 2 qubits for each consecutive c-NOT gate. (The diagram is Figure 5 of the following notes...

With the phenomenal speed to be expected from quantum computers in the future, todays encryption techniques such as RSA will be pretty much useless. A quantum computer could factorise 600bit+ numbers in a relatively short period of time. Aside from Shor's algorithm, are there any other...

So last year I took a course in quantum computing, but I didn't understand how can you build quantum computer? I mean do you have literature on the technical issues of physically engineering such an apparatus? The course I took was really theoretical, but I don't understand yet of how to...

Dear Friends, I have to solve a two dimensional coupled oscillator problem numerically. Hence the easiest way is to use the matrix representation of the creation and annihilation operator and then find the required hamiltonian. To find the time evolution of the state I have to...

I am currently majoring in Electrical Engineering with a deep interest in quantum computing and quantum cryptography, the former being my greater passion. I'm certain that most, if not all, of those working in the field of quantum computing have at least a PhD in Physics. The same goes for...

Homework Statement Let a one-qubit system be in the state [SIZE="3"]\left|ψ\right\rangle = \frac{\sqrt{15}\left|0\right\rangle + i\left|1\right\rangle}{4}. If we perform a measurement to see whether the qubit is in the state [SIZE="3"]\left|x_{+}\right\rangle = \frac{\left|0\right\rangle +...

Hi, I found this great free online class about Quantum Computing on coursera.org. The class is called "Quantum Mechanics and Quantum Computation" taught by Umesh Vazirani. - https://www.coursera.org/course/qcomp - *Umesh Vazirani is the Strauch Distinguished Professor of Electrical...