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Comment Re:Tentative summary (Score 1) 150

Thanks for the excellent summary of what the two articles seem to say. If I were competent with the Slashdot interface, I would mod this up for "Informative," but I can't find the right buttons. The puzzle, which I hope someone with real understanding of quantum theory will explain (I will dig into the original paper, but not with great optimism for my understanding):
  • It seems that when a single electron hits this blob of helium, it has many possible paths through the helium in bubbles, each with a different wave function (which, as I understand, has complex values that add up to values whose magnitudes are probabilities at some point that I don't understand how to characterize). So far, I'm cool.
  • Presumably (I don't see any mention of this in the articles) an electron eventually pops out of one of the bubbles, and we could (even if we don't at present) find out which bubbles were inhabited and which not.
  • At that point, my crude understanding of quantum theory indicates that only the inhabited bubble(s) existed in a coherent description of passage through the helium.
  • But, these guys are observing all of the bubbles, including those that don't turn out to be inahbited, and therefore according to my crude understanding shouldn't have been there.

My best highly ignorant guess is that the bubbles are all there, and the qualities of a bubble determine its likelihood of being inhabited. Even that highly ignorant guess begs a lot of questions regarding the mechanism that gives the bubbles fractional-charge-like qualities. Boy, do I wish someone with real understanding would really explain things.

Comment Re:Not a contract (Score 1) 226

IANAL, but I've studied contract law for Scotland. A contract is an offer and an acceptance, that's all it takes.

From Wikipedia: "In common law legal systems, a contract (or informally known as an agreement in some jurisdictions) is an agreement having a lawful object entered into voluntarily by two or more parties, each of whom intends to create one or more legal obligations between them. The elements of a contract are "offer" and "acceptance" by "competent persons" having legal capacity who exchange "consideration" to create "mutuality of obligation." ( It's not obvious to me whether the purchase of a ticket with stuff written on the back constitutes such "acceptance," so I hope that someone with deeper knowledge will pitch in. I have read statements from apparently knowledgable people to the effect that opening a package does not constitute "acceptance" of the shrink-wrap license conditions, nor that use of a service constitutes "acceptance" of everything in the published "Terms of Service" or "End User License Agreement." I have also read that "acceptance" requires some ability in principle for each party to negotiate details. The "mutuality" part is also not obvious. The exchange of money for the ticket and the implicit right to enter the venue at a particular time seems clear to me, but it is not at all clear that there is any "mutuality" in the additional terms stated on the back of the ticket or in the program.

Comment Reading is not agreement (Score 1) 226

You've agreed to not talk to a small gathering of your own friends about the game too.

No. The vendor of the ticket has stated its refusal of permission, but you haven't agreed to that condition. The enforcability of the prohibition depends on lots of subtleties in the law, but it is certainly not based on an agreement.

Comment Not a contract (Score 1) 226

it's contract law (essentially)

I am almost certain (given that IANAL) that there is no contract here, because a contract must be negotiated and must have some consideration passed in each direction. I think that the distinction is more than a quibble, because contract law is quite different from license law and rights of venue owners. In particular, each of these branches of law appears to have different limitations on which sorts of requirements may be enforced, and how they may be enforced.

Comment Ticket is not a contract (Score 1) 226

I'm as certain as I could be without being a lawyer that there is no contract between the vendor and buyer of a ticket. I *think* that the ticket represents a license provided to the buyer. I definitely need a lawyer (not currently available to me) to determine what sorts of limitations on that license are and are not enforcable, and what sorts of remedies are available to the vendor when a buyer violates a limitation expressed by the vendor.

Comment Getting better access to information (Score 3, Interesting) 90

(2) Is it easy for a non-academic to get the required data?

I am not familiar with this particular academic community, but generally it is not easy for an academic to get data. The most useful resource is probably the co-operation of those who have gathered the data, and in order to get that you have to find out who they are. The inclination to be helpful varies immensely across disciplines and people within disciplines, but all you lose by trying to make contact is possible embarassment. Step 2 in the list below will give you a tag to use when introducing yourself, which may make you feel less awkward and therefore may improve co-operation.

I suggest 3 steps, in increasing cost, that are likely to help:

  1. 1. Get a community membership in the nearest university library. This should be cheap enough to be a no-brainer. It doesn't matter too much which university, because a lot of materials will be online through their Web catalogue, and there will be interlibrary loan. I'm not sure whether small 4-year colleges and community colleges have similar arrangements, but it's worth checking if one of those is much more convenient than a research university.
  2. 2. Join a professional society, and/or the special interest group of a professional society, interested in your topic. Costs vary wildly, order of magnitude $100 to $1,000 per year. The Association for Computing Machinery (ACM) and the Institute of Electrical and Electronics Engineers (IEEE) probably have interest groups, and there are almost surely such groups within some cognitive science societies, but I am not familiar with those.
  3. 3. Attend a conference sponsored by a group from step 2. This is likely to cost $1,000s when you add up travel, hotel, registration. If you have the time, and get lucky on location, you can save a bunch on travel. Saving by staying far from the conference hotel is usually a mistake. The value of the conference is less in attending talks than in meeting people, and having breakfast in the same hotel with everybody else can make a big difference. The success of unsolicited introductions will vary immensely across the people you try to meet, but you lose nothing but embarassment by trying. The main thing you can do to improve success is to avoid the Charybdis & Scylla of diffident awkwardness and bluff. Let on that you're an outsider, but don't downgrade whatever insight/ability/motivation you have. You'll probably have the greatest success meeting people who are networked in, but are not famous stars. That includes grad students and postdocs. It may be nice and polite to hang out with other outsiders, but probably not productive for your mutual goals.

Comment Automated programming succeeds, redefines itself (Score 2) 168

Attempts have been made in the past to automate programming, it's never worked very well

On the contrary, automated programming has worked repeatedly, each time redefining "programming":

  1. Machine language automated the programming of patch boards.
  2. Assembly language automated programming in machine language, particularly the assignment of addresses.
  3. FORTRAN automated assembly language programming, particularly the programming of formulae into sequences of operations.

Each time someone automated "programming," the word stopped referring to the automated part, and referred to the remaining part of algorithmic problem solving. After FORTRAN, the pieces of automation were less clearly ordered, and less likely to be referred to as "automated programming," but re-entrant procedures, recursive procedures, virtual memory, garbage collection, class instantiation, tail recursion removal, ... all automated activities that were formerly part of "programming." In all cases, whatever specification remained to be done by hand became the new "programming."

Comment Automatic programming works, and redefines itself (Score 2) 168

Attempts have been made in the past to automate programming, it's never worked very well

On the contrary. The first attempt to automate programming produced assembly language, which automated the assignment of addresses to variables and instructions. The second one produced FORTRAN, which automated the "programming" of formulae into sequences of individual operations. Every time we successfully automate some programming activity, the nature of programming changes.

Mike O'Donnell

Comment Tall screens, essentially square (Score 4, Interesting) 591

I agree. I want the highest possible screen. Wide screens appear to be catering to movies, games, and the dishonesty of diagonal measurements (a wide screen gets a greater diagonal measurement than a square screen with the same number of pixels). Documents are best viewed with vertical space.

Comment Different meanings of signal "below" 20 KHz (Score 1) 749

a 44.1kHz sampling rate can perfectly encode any signal that is =22.05kHz, and nobody can hear over 20kHz.

People keep saying this, but it involves two different meanings of a signal with content below 20 kHz. The Nyquist theorem says (correctly) that, for an infinite number of perfectly accurate samples at S Hz, there is only one signal agreeing with those samples and containing Fourier components all below S/2 Hz. Fourier components are infinitely long sine waves, with no variation in frequency or amplitude. People hear components that are modulated sine waves with carrier frequency below (for most of us, far below) 20kHz. "Modulated" means that the amplitude and/or frequency (usually both) vary. Fourier components of a signal with arbitrarily high frequency affect the modulation of audible components with arbitrarily low frequency. Whether the effect on that modulation is audible is a very subtle thing, quite difficult to measure, and not completely known at present.

Comment Reproductions @ different rates not identica (Score 1) 749

Not if you can mathematically prove that the two sound reproductions are identical

The best possible signal reproductions at different sample rates are not identical, so of course you can't prove such a falsehood mathematically. The argument is that they are indistinguishable in human perception. That's a very difficult thing to study, with many variables that are hard to control.

Comment Fourier components & audible components differ (Score 1) 749

A modulated (varying frequency or amplitude) signal with an audible carrier frequency has Fourier components of unboundedly high frequency. These components can, and sometimes do, have an audible effect on the modulation. The value of >44.1 KHz sampling is debatable, but it's not dismissable mathematically.

Put another way, the "components" below 22.05 KHz that are preserved by 44.1 KHz sampling are the infinitely long unmodulated sine waves of Fourier analysis. The "components" that we hear are modulated sine waves. Cutting off the Fourier components above 22.05 KHz changes the modulation of the audible components below 22.05 KHz. Whether that change is perceptible depends on deep study of human perception, not on the mathematics of sampling.

"Don't worry about people stealing your ideas. If your ideas are any good, you'll have to ram them down people's throats." -- Howard Aiken