Why now is the best time to study quantum computing (2014)
arxiv.org
arxiv.org
Quantum computers will likely manifest themselves as co-processors, and you'll have a nice well-abstracted API to access those implementations within traditional languages, i.e.
#!/usr/bin/env python4
from quantum import qc
qc.init(device="/dev/quantum0")
factors = qc.factor(15)All of that design infrastructure needs to be built by somebody, and that somebody stands to make a forunate. The tasks you listed are a decent summary of the likely eventual outcome.
But:
• Who will do the work to create this beautiful API? • Who will create this coprocessor architecture? • Will this theoretical stack be built by Microsoft, Amazon, Google, etcetera, or be FOSS?
These questions are completely unanswered, and will affect my users of whatever quantum. When analyzing data, one cannot usually just gloss over the underlying math. All abstractions, by definition, are incomplete.
But that's the exciting thing about right now. Most inventions occur when science outruns engineering. When engineering and cutting edge science just about to finally converge, that's when market opportunities are most prevalent.
The vast majority of software engineers---even if we filter to just the set who have actually used GPUs for a project---only know the high-level APIs (OpenGL for graphics, CuDNN for AI, etc.). Fewer engineers are familiar with the more general-purpose APIs (CUDA, OpenCL, etc.), and even fewer still know any of what goes on underneath those layers.
Bottom line: it takes a relatively small community of people to build tools for everyone else to use. People will need to know how to use the highest level of APIs, but most need not understand what goes on underneath that.
Google wrote a nice one that makes use of WebGL: http://www.quantumplayground.net/
Quantum algorithms are so vastly different in nature from classical algorithms that it will necessarily be its own branch of science. It takes an entirely different mode of thinking; for example, basic physics laws forbid you from copying a qubit that is in an arbitrary quantum state. That's right, you cannot copy a quantum variable as that would violate fundamental laws of the universe as we know it. Most computer scientists are not used to that kind of thinking. However traditional computer science thinking will not vanish, because quantum computers will never be a replacement for classical computers; they are good at speeding up very specific classes of computations and not particularly suited for general computing or building interfaces with the outside world.
Quantum computer science and classical computer science will be two fields of study that will both continue to evolve in their own right.
If I had to bet I would guess that quantum programming is going to be more like "linear programming", where instead of programming the algorithm instructions you program by preparing the inputs that you will pass to the specialized subsystem.
Seems naive to me.
Quantum computers may work in analogous ways, but making predictions about what you'll need to know is presumptuous. `factor` is the easiest way to use a quantum computer in an "api" sense and, by itself, isn't very useful at all.
Do you any other videos on this topic you would recommend watching?
I don't know any other videos, but I really like Nielsen/Chuang's book on Quantum Information. The first chapter is available for free:
http://www.michaelnielsen.org/qcqi/QINFO-book-nielsen-and-ch...
Michael Nielsen has a great blog btw where he talks not only about quantum computing but about machine learning and other interesting subjects as well.
http://de.slideshare.net/japh44/lets-build-a-quantum-compute...
I often wonder what will happen at the 0-day quantum machine where it's not just a few qbit but the real deal.. I think anyone in possession of such technology will be able to crack any SSL certificate, and thus gain access to almost anything online. I wonder if criminal organisations aren't secretly investing in such thing? And, not to be paranoid, but we're almost certain it will be possible to build them, wouldn't it be prudent to start investing in the defense against such things? What kind of security could we have to counter a quantum computing? Would it only be possible to use quantum computing to defend against quantum computing?
Timing the market would be hard. I remember seeing an article in 1999 talking about quantum computing, as if it were "just around the corner". Tons of advances have been made in the field since then, but we could still be 10-20 years out from QC being available/ubiquitous.
Now, however, it's probably the case that the scientific and engineering challenges are the biggest hurdles - we already have the society and economy hungry for more computing power. Assuming the necessary breakthroughs can be made to make quantum computing a reality in the next 10-15 years (obviously a big assumption, and not intending at all to sweep that aside, it could take decades, but just let's make that assumption) it's not at all difficult to see how it could rapidly find its way into production and then ubiquitous industrial application, and 20 years then does not sound outlandish at all.
Not at all. As it is believed currently, there are a few problems (BQP space) such as the discreet logarithm that quantum computers can solve quickly. But lots of other hard problems, probably including all NP problems, cannot be solved exponentially faster by a quantum computer.
See also http://security.stackexchange.com/questions/48022/what-kinds...
"Back in the 90s, I asked leading quantum computing researchers when quantum computers would become available, and I was told 'in 10 years' time'. I asked them again 10 years later, in the 2000s, and was met with the same reply. And I've asked again just recently, and I was told, once again: 'in 10 years'. Now, I'm a computer scientist, so I my prediction of the future can only be that what has repeated itself will continue to do so. According to this logic, quantum computers will never be available."
(I'm quoting very loosely, because this was just an off-topic remark during a lecture I attended a year ago, so I don't remember the exact phrasing. But I do believe that this was the gist of it).
I'm genuinely afraid that quantum computing will just remain a purely theoretical field, and that we won't see any practical applications to it. To me, that does not make it worth pursuing. I'd love to be wrong, though, because it sounds super interesting.
No, it just means that time until quantum computers are available is distributed exponentially.
I mean to say that the introduction of a quantum computer is just a single, once occurring event.
The exponential part is more like e^(-x) and refers to the exponential distribution [1] that gives the distribution of intervals in between Poisson events. So if its 'distributed exponentially' (whatever that means for a one-off event), the joke is that this would then give rise to the situation where researchers are always correct guessing 10 years off, even if they've been saying that for decades.
One-off event is not a problem. You can clone the world many times at the moment when scientists made their prediction and find the distribution over ensemble instead of over time.
https://www.technologyreview.com/s/544421/googles-quantum-dr...
No bullshit guide to linear algebra https://gum.co/noBSLA
Here's an excerpt from Chapter 10 on QM: https://minireference.com/static/excerpts/noBSguide2LA_previ... I also give a (non-hype) overview of the potential and obstacles associated with quantum computing.
We can theoretically make a lot of simultaneous computations but are we sure we will not need exponentially more energy or time to get the result of computation when we add more qubits in future quantum computers ?
The minimum free energy that must be expended to operate a computer is theoretically very close to zero, since it is not strictly necessary to use irreversible primitives[0], such as NAND gates, which is something that we do in traditional computers. For irreversible elements the theoretical requirement is about kT*ln(2) at temperature T. DNA uses about 100 kT per bit copied.
I really recommend that you take a look at Feynman's introduction to quantum computing[1].
[0] http://www.cs.princeton.edu/courses/archive/fall04/cos576/pa...
[1] http://www.cs.princeton.edu/courses/archive/fall05/frs119/pa...
in all seriousness though, I heard someone talk about their qc research a year or so ago and it was fascinating but I imagine debugging such systems could be quite the challenge
But we don't know that at all. I would guess fifty years from now will be an even better time to study quantum computing.
It has a few conceptual errors, and if you use it in a midterm the TA will mark it as a fail, and probably try to ban you from the university
The important detail is the back story of that answer, that is unluckily unknown:
* If it's genuine and he studied alone a few Wikipedia pages and similar stuff, then it's a good enough answer, he got the general idea, but he still don't understand the details. He must try to understand something about the qbits that still have only two states, and that they can combine exponentially. Keep trying, good luck.
* If it was a PR setup, and a collaborator wrote it, then it's a bit sloppy. It's like going to a milk factory and saying that their business is related to squeezing cows. Next time try contact a physics. (But remember to redact the 2 pages about complex Hilbert spaces, it's difficult to give an short, ineligible and correct explanation.)
One of the most difficult challenges in science is to find the exact level of complexity in an explanation to fit your audience. You can see this if you go to a talk at a university -- often researchers are so obsessed with looking smart that they begin with extremely difficult material that 10% of their audience understands and go on from there, losing another percent every 10 minutes.
Sometimes people will give a 'general audience' talk that is so simplified that everyone understands it but nobody gets anything out of it; it's just vague platitudes and intuitions.
Most of Trudeau's language is so vague it could neither be called correct or incorrect (with a few exceptions).
I think the purpose of it was: 1) to acknowledge to the researchers there that he took the time to learn /something/ about their highly technical field and that he finds it interesting and exciting. Contrast this with, for example, any politician that has ever existed in the history of the world.
2) to give a vague general explanation of what the phenomenon is that would make sense to his general audience, who don't even understand what computers are.
Most importantly NOT: 3) To prove to scientists he understands science as well as they do.
I think his speech was excellent in light of those two goals.