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Rybka Solves the King's Gambit Chess Opening

john83 Re:+ / - 5.12 is a lot of difference (206 comments)

The score is about equivalent to being a rook down without compensation. Even strong club players could beat computers from such positions. Of course, what it really hinges on is Rybka's ability to evaluate the notion of compensation, but I can believe that the percentage of positions Rybka evaluates at -5.12 or worse in which there exists a win for the 'weaker' side is very small. So, yes, not a proof, but a strong practical indicator.

more than 2 years ago
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Dysfunction In Modern Science?

john83 Naturally (155 comments)

Surely any competitive system to select people for desirable posts is going to encourage dubious behaviour? Those editorials don't seem to offer very significant changes, just new metrics for people to game. It's not just academia either - every career where your value is measured by some proxy metrics is going to see unethical behaviour from people near the cut-off.

about 2 years ago
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Mars Mission Back In the Cards After Budget Cuts

john83 Re:Give it a rest (146 comments)

The atmospheric pressure on Mars is quite variable, from 0.0044 bar to 1.15 bar (if it sea like ours, one entire hemisphere would be under water). The figure you've quoted seems to be from around as high as you can go. The other end of the scale is around earth normal or even a bit higher. Temperatures are also more hospitable. Also, Lunar dust gets everywhere. There is no simple answer here.

more than 2 years ago
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Pirate Party Gains Another Seat In EU

john83 Re:The only people in the world and the party that (156 comments)

Does it bother you at all that that is not at all what he said? I ask because it makes me sad to see a human being incapable of parsing a very simple piece of text. Many people are dispirited by the realpolitik practised by most parties with any actual power, by the lobbying power of industries and of special interest groups with views which appear grotesque or simply stupid, and by political corruption. Furthermore, many countries have voting systems which are conservative - the populace tend to vote for the incumbents, or oscillate between two power blocks which are not radically different from one another. To state that most parties appear not to represent ones beliefs is very different from saying that one has almost no beliefs. Democracy, as it is currently practised, is certainly not a pleasant sight for an idealist. I'd do something about it, but I don't think I have the stamina, money, cynicism and skills. At least I can understand a simple post though.

about 3 years ago
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Mathematically Pattern-Free Music

john83 Re:'pattern-free'...aka 'noise' (234 comments)

No, white noise is random, which wouldn't have the same properties as this. For a start, it would have the same key more than once.

about 3 years ago
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Mathematically Pattern-Free Music

john83 Re:Mathematics of Ramsey (234 comments)

Well spotted (by which I mean, mod parent up!). He could have used a larger primitive root of 89, like 30, and that wouldn't have occurred.

about 3 years ago
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Mathematically Pattern-Free Music

john83 Re:Mathematics of Ramsey (234 comments)

Interestingly, if you try to generate more than 88 notes by the method Rickard described, they start to repeat periodically.

about 3 years ago
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Mathematically Pattern-Free Music

john83 Re:uses each key once (234 comments)

It is, but not of the kind they were looking to avoid. There are Costas arrays without that pattern, but they're not known for sizes over 28 x 28. They're called 'sporadic' arrays, and they're actually the most common type for small sizes (there are infinitely many generated by field theory, but that's not a fair comparison as we can't find large sporadic arrays).

about 3 years ago
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Mathematically Pattern-Free Music

john83 Re:Wha? (234 comments)

Please note that "note a musical guy" was not intended as a pun, but was in fact my brain on too little sleep.

about 3 years ago
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Mathematically Pattern-Free Music

john83 Re:Wha? (234 comments)

I'm note a musical guy, but I understand the maths, so I'll try to answer this.

It would help if there were some definitions for "random" and "pattern-free" in this context. I find it annoying that he several times says that random music is not pattern-free.

1. He never plays the same note twice. (A Costas array is a permutation) In a random piece, the same note can (and probably will) appear more than once.
2. If he plays middle A, then middle B (consecutive notes), he'll never play consecutive notes (e.g. C_0 and D_0) again. 3. If he plays middle A, then something else, then middle B, he'll never play consecutive notes spaced by another note again. 4. If he plays middle A, then two other notes, then middle B, he'll never play consecutive notes spaced by two other notes again. 5. etc. 6. The same applies to pairs of notes two notes apart (e.g. middle A and middle C), three notes apart, etc. 7. Finally, he uses a Golomb ruler for the spacing between notes. I'm note quite sure what he did there, but possibly each spacing is unique. Can someone else explain? At any rate, a Golomb ruler defines unique gaps such that you get every possible gap between some pair of marks on it. (Think of a 4 cm ruler with 0 cm, 1 cm, 2 cm and 4 cm marked on it. You don't need a mark at 3 cm because you can get that from the gap between the 1 cm mark and the 4 cam mark.)

It is true that their definitions are not equivalent, but it seems that he is implying that you cannot generate "pattern-free" music using randomly played notes, and that -depending of the definition of "pattern-free" of course- seems very, very unlikely.

Can't is note quite true, but won't is more like it. Consider 3.14159265358979323 - the first 18 digits of pie. Random digits? Maybe (randomness, as you note, needs to be defined). However, look at triplets: 141, 535, 979, 323. Played as music, people will hear repetitions like that. Or at least, that seems to be the theory; I have no ear for these things to test it. Maybe you can hear them?

about 3 years ago
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Mathematically Pattern-Free Music

john83 Re:More! (234 comments)

There are additional possible solutions. They used an 88x88 Costas array for the notes, and a length 88 Golomb ruler for the intervals. I'm not sure how many Golomb rulers there are of that size, but there are more Costas arrays of that size - at least as many as there are primitive roots of 89.

about 3 years ago
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Mathematically Pattern-Free Music

john83 Re:I can go one better (234 comments)

Random != no pattern

You might create a tune with no pattern but chances are there will be a pattern of some kind in there.

Exactly. This is why sports fans think that there's such a thing as form. Human beings are very bad at judging randomness - we actually bias towards alternating patterns, which is decidedly non-random.

about 3 years ago
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Age Bias In IT: the Reality Behind the Rumors

john83 Re:C programmers? Wanted! (582 comments)

C is not that uncommon, particularly among engineers.

more than 3 years ago
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Portable Microscope Uses Holograms Instead of Lens

john83 Re:Infrastructure (64 comments)

I'm an academic working in optics. This is holographic, not OCT. The difference is small - mainly the coherence length of the laser, but essentially the holographic microscope has slightly better resolution at the cost of much worse rejection of out of focus light. So this device is probably better for examining a biopsy or some water for contamination or something rather than looking at a hunk of tissue, which is where OCT shines. The holographic approach is better in one other way - it grabs an image in one shot, where as most other 3D techniques require scanning. That could be an advantage in in-vivo imaging of cells.

more than 3 years ago
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Is the Master's Degree the New Bachelor's?

john83 Re:More degrees = More Skeptical (330 comments)

I'd mod the parent insightful if I had the points. Most of the PhDs I've worked with have been very conscious of their limitations. Maybe it's a cultural thing, or maybe the OP is bringing his own biases to the table.

more than 3 years ago
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Crime Writer Makes a Killing With 99 Cent E-Books

john83 Re:Just like the music industry (445 comments)

All the more so as the modern publishing industry is often rather lax in proof-reading standards, making the one lasting use for them rather less important than it might otherwise be.

more than 3 years ago

Submissions

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Foundation "dismayed" at publication of public domain manuscript

john83 john83 writes  |  more than 2 years ago

john83 (923470) writes "The Irish Times reports that publication of a new children’s story by a Dublin publishing house has been criticised by The Zürich James Joyce Foundation, which owns the original manuscript of the story. In a statement, the foundation said it “never permitted, tolerated, condoned or connived in this publication, and it rigidly dissociates itself from it”.

The Dublin publisher, Ithys, said the unpublished works of James Joyce were in the public domain as of January 1st. The attempt by “the Zürich Joyce Centre” (sic) proprietarily to assert some right on the document was “preposterous”. “The said centre has no rights in law in the copyright of the papers donated (given free) by Dr Jahnke.”

The stated goals of The Zurich James Joyce Foundation include "... keeping alive the memory and work of the Irish writer James Joyce ..."

Joyce died in January 1941."

Link to Original Source
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john83 john83 writes  |  more than 7 years ago

john83 writes "Global Warming is the subject of a lot of debate these days, and some scientists have tried to consider fixes more drastic (and unfathomably expensive) than banning light bulbs. "At the NASA Institute for Advanced Concepts (NIAC) meeting last fall, Roger Angel, an astronomer and optics expert at the University of Arizona, produced a highly detailed — and highly futuristic — proposal for a sunshade huge enough to cut incoming sunlight by 1.8 percent. That, he says, should counteract the warming expected from a doubling of atmospheric carbon dioxide." Story. NIAC has previously brought us such ideas as magnetised beam plasma propulsion which was discussed on Slashdot."
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john83 john83 writes  |  more than 8 years ago

john83 (923470) writes "The Register is running a story about the new Irish RFID passports. Unlike the US equivalents, they don't have a layer of foil in them to provide at least a minimal level of protection from skimming, so people's personal data is quite exposed. Digital Rights Ireland have criticised the move:
The technology the Department of Foreign Affairs chose to protect the information in the chip from being read remotely (eavesdropped) by anyone within 5 metres (15 feet) is called Basic Access Control (BAC).

Basic Access Control is used by other countries, such as the Netherlands to protect their RFID Passports from eavesdroppers. However, a Dutch security testing lab called Riscure has examined the reliability of BAC and found that it is quite possible for a determined eavesdropper to break the control with a handheld reader, and an ordinary PC from within 5 metres. (Slides outlining this attack method)
"
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john83 john83 writes  |  more than 8 years ago

john83 (923470) writes "Bruce Byfield has interviewed Linus Torvalds (that's the guy behind the Linux kernel, you philistine!) over on linux.com. Torvalds discusses his relationship with the GPLv3 drafters and his reasons for not supporting the licence. He's quite critical of the licence, saying "... if you actually look behind all the nice words, it's just a polite way of saying, 'We want to hijack the code of those projects that use the Apache license, too, and turn that code into GPLv3." At the same time, he insists that he is, as the article puts it, "a GPLv2 supporter, not a GPLv3 basher"."

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