361–370 of 373 posts
Hi Scott There are non-quantum physical systems that exhibits positive and negative amplitudes and interference. Can I factor large numbers by throwing rocks in a lake and measuring the water height at the right place? Why not?
Hi Scott, If somebody claims that there is no freedom of will, what what you accept as a reasonable proof? It seems that one can be sceptical even in presence of extremely precize predictions as it my be easier to alter memory about predictions than to produce them.
I’m not sure I fully understand your argument, but if someone showed that they could perfectly predict the actions of the people around them, say hours or days into future, placing the predictions into a sealed envelope or a cryptographic commitment and revealing them later, then to whatever extent fraud and the like had been ruled out as explanations (in the ordinary experimental ways, and possibly with the help of…
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Dah. Hang on, what am I talking about- chess has a finite number of moves so the "language" is finite. That means it's learnable in polynomial time, from finite examples ... in principle :)
Right, but even if chess were infinite, we could still imagine an algorithm that would output the smallest explicit rule set that was consistent with all the games it had seen so far, and that would quickly (though how quickly?) converge on the correct rules in the case of chess, even if it would be up against undecidability when trying to do the same thing for a completely arbitrary game.
Hi Scott - What was the best part/most favorite thing about your sabbatical? Can you explain why Forrelation is a guiding light for quantum deep learning these days? As a bonus - it would be nice to see a walkthrough - commentary of the recent oracle separation proof of Tal and Raz and how they used Fourier transforms specifically.
My favorite part of my sabbatical in Tel Aviv was having some actual time to do research. My second-favorite part was the hummus. Forrelation is not a “guiding light for quantum deep learning.” I’m not even sure if there’s such a thing as “quantum deep learning” that’s sufficiently well-developed to deserve the name. You can use Forrelation as a separating example for some other quantum learning problems, e.g. k-mean…
Have you seen https://arxiv.org/abs/1806.09729?
I would call that quantum deep learning, or more accurately, foundations of quantum deep learning.
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My favorite part of my sabbatical in Tel Aviv was having some actual time to do research. My second-favorite part was the hummus. Forrelation is not a “guiding light for quantum deep learning.” I’m not even sure if there’s such a thing as “quantum deep learning” that’s sufficiently well-developed to deserve the name. You can use Forrelation as a separating example for some other quantum learning problems, e.g. k-mean…
Just as a quick followup: Avishay Tal has confirmed for me that, indeed, their proof still goes through if you replace the Fourier transform by any other unitary matrix with bounded entries.
Hi Scott, I'm astounded by the accomplishment of AlphaZero in quickly becoming a chess master without chess specific programming. Could a program of the same kind be adapted to infer or deduce the rules of chess from a large set of valid games? Or is that a different kind of problem? If so, could it be adapted to learn the rules when we're not clear on them either, like those for the games of love or politics?
Most of the rules of chess are trivial and thus should be deducible from observing less than one complete game. Rare things like castling might take a couple of games. Love and politics have rulesets that are many orders of magnitude more complex; so complex that we don't even know how to write them all down.
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Right, but even if chess were infinite, we could still imagine an algorithm that would output the smallest explicit rule set that was consistent with all the games it had seen so far, and that would quickly (though how quickly?) converge on the correct rules in the case of chess, even if it would be up against undecidability when trying to do the same thing for a completely arbitrary game.
It depends on how you mean "converge". It would certainly tend towards the full ruleset, learning more of them, or more accurate versions of them, the more examples it saw. It would not really terminate though, at least according to the learnability results from inductive inference.
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It depends on how you mean "converge". It would certainly tend towards the full ruleset, learning more of them, or more accurate versions of them, the more examples it saw. It would not really terminate though, at least according to the learnability results from inductive inference.
Results from inductive inference show that you’re not going to converge in general . In the specific case of chess, however, my point was that we, because we know the complete list of rules, could plausibly look in from the outside and say after some finite point: “ah yes, now the system has gotten all of them.”
The article you quoted above is a good example. It's main claim is that an evaluation function was learned without knowledge of rules or hand-crafted features, i.e. explicit human participation.
It's a political issue, really. And a silly one- there are domains where very useful background knowledge is available; physics, language, mathematics, etc. There's no reason not to use it.
In chess, for example, it might be possible to learn a decent set of rules just by carefuly choosing the examples to feed to the learner. Or, indeed, evaluating the learning so-far, therefore acting as an all-knowing Oracle.
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[1] Well, strictly speaking active learning is where the system asks the user for examples/ counterexamples, but there's different options and what you suggest would fit in there.
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> if we can't test the thing then the universe isn't going to punish us either way for believing or not. If we can’t test the thing then what we are discussing is faith, not science. Nothing wrong with faith and beliefs but I think it’s important to differentiate between these things and science because often times science is used as a basis for untestable beliefs and then people really start to think that those unte…
Do you have any empirical evidence for any particular QM interpretation? If not, does that make them unscientific?
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In your 35 second blurb, and the New York Times article, it seems like the point you're making is that interference is the main way that quantum computers work. But what makes quantum interference special over other kinds? You can get interference in sound waves, light waves, radio waves, etc. You also mention that magnitudes can be complex, but the same is true of other kinds of waves; complex numbers are used for d…
The difference between QC and all those other examples of interference is that, in the case of QC, the interference happens in configuration space rather than ordinary 3-dimensional space. And configuration space is enormous ; it has a dimension that grows exponentially with the number of particles. The number of paths that could interfere with each other to produce a given amplitude is likewise exponential (in that…
Would you consider writing an in-depth article on configuration space and how it applies to QC (and possibly other research) and sharing it here on HN someday?