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Comment Re:So, what is the digit in decimal? (Score 4, Informative) 299

We only know how to calculate it in binary (or any base that is a power of 2). You can't convert to decimal without know all the rest of the digits.

Parent is correct, digits of pi can be calculated independently in base 2, 4, 8, 16 or 2^n since the 1990s. So, it is possible to calculate the 2,000,000,000,000,000th number of pi without calculating the digits before that one. Now, if we want to calculate the digit in decimal (or converse the binary digit to decimal), we need to calculate all of the two-quadrillion digits. Knowing this digit is in itself not very interesting.

Comment Re:Welcome Aboard (Score 1) 654

Except the people who think they're being cleaver and claim that "pure communism" was supposed to be Libertarian Socialism, aka "Anarchism." it wasn't. Mikhail Bakunin and Karl Marx were arch-rivals in the First Internationale over this issue, and Marxism, slightly refined by Lenin and Trotsky, and established by the Bolsheviks in the Soviet Union was the real McCoy.

Communism is a "social system based on collective ownership". The word is originally French, existing since the 12th century. Victor d’Hupay was in 1785 the first (afaik) to use the word in its modern meaning. Marxism (19th century) is one form of communism, the form which redefines communism as "social/political system based on state ownership". "Pure communism" is the end goal of Marxism, a free state which they tried to reach by installing a dictatorship... (Sorry - as an anarchistic communist I had to try to be "cleaver".)

Comment Re:And when it fails this test too (Score 1) 284

No I'm not. You are confusing the first and second incompleteness theorems.

OK, you made me read your post again.

(incidentally you forgot the assumptions Godel made for 2), showing that for example, there are consistent maths, we just don't use them, as they're not infinite, and not "generally useful" whatever that means)

There are indeed limited mathematics which are built upon first order logic and which are consistent and complete. They can even be infinite, if you allow for an infinite number of axioms by using an axiom scheme. But they are not strong enough to express arithmetics.

Additionally you forget the followup proofs, there are no consistent theories that can prove the consistency of "meaningful" mathematics (ie. +, -, *, /, n -> n + 1, ...). It's not just that the consistency of Peano arithmetic cannot be proved inside Peano arithmetic, it can't be proved, at all (in any meaningfull way : the only way to "prove" it is to accept it's correctness as axiom).

Using nothing but logic, one can build two kinds of mathematics which are strong enough (i.e. being of second order) to express arithmetics:
1) consistent (but incomplete) ones,
2) inconsistent ones - you say that all mathematics is inconsistent, but that is just plain wrong. Unless if one uses a paraconsistent logic to prevent the ex falso sequitur quodlibet, inconsistent mathematics is trivially complete, because all well-formed formulas would be true.
3) Gödel proves that the third kind, mathematics which are complete AND consistent do not exist.
3') One could consider mathematical theories of which we do not know if they are consistent or not as a third kind of mathematics, I don't know if anybody has ever constructed a mathematical system of which it can be proven that it is undecidable wether it is consistent or not (sounds like a nice project actually.)

So really math is not consistent (if something cannot be proved, even if not actually disproved, you cannot reasonably say that it *is*, because it isn't). You can NOT say that math (arithmetic) is consistent, that's WRONG. You *can* say it's inconsistent

You are confusing "consistency" with "completeness".

(if you've proven, correctly, that a plane can never be observed flying, is it really such a stretch to say that it's going to crash when it's haning up in the air and time is frozen ?).

I have no clue what you are talking about.

This is also not the sole problem with numbers. There are all sorts of unsolved paradoxes with even the natural number "infinite". (more general there are paradoxes that apply to any collection with infinite elements)

Yes, that's why there is a movement called finitism in maths.

And this is talking about *just* natural numbers. rational numbers and, God help us, real numbers have much, much worse problems than mere doubts. It is known that rational numbers are inconsistent, and real numbers cannot be proven to even exist. There are no known ways to construct real numbers that are not simple extensions of rational numbers.

Of course the existence of real numbers can be proved: take a triangle with a 90 angle & with both legs on that angle having a length of 1. Then the length of the third leg is a real number, SQR(2). It is easy to proof that SQR(2) is not integer nor rational. Now, defining and constructing real numbers is harder and there are non-standard mathematics which try to address the problems you hint at.

Comment Re:And when it fails this test too (Score 1) 284

Sorry, the second sentence of my last paragraph should read as "axioms of relativity do not lead to theorems" (in stead of 'theories'.)
The theory of Goldblatt is a "first order theory", logicians like that, because it is decidable. The theory of Schutz in categorical, the mathematician like that, even if it is undecidable.

Comment Re:And when it fails this test too (Score 1) 284

I agree with m50d that it is not relevant for the reason he gives above.

The Gödel theorems are interesting for the study of the foundation of mathematics and more specifically for the study of the relation between logic and mathematics. Using it outside that field is at least tricky, and more often than not crackpottery.

Out of a set of axioms (or out of a set of hypothesis) you use deductive logic to prove some theorems which are true if the axioms are true. The axioms together with the theorems form a theory. The question of completeness is: can we construct a proof for every true stament in that theory, or do there exist true statements which cannot be proven. The question of (in)consistentcy is: can we construct a proof for a false statement? All this is about the internal properties of a theory.

Now back to your question: relativity theory and quantum mechanics have different sets of axioms. The axioms of relativity do not lead to theories which are in contradiction with other theorems of the same theory (I am not sure about this for general relativity, there are however several sets of axioms for special relativity which have proofs of consistency*). I guess the same holds for QM**. The problem is: theorems of relativity are in contradiction with theorems QM, so this is a problem between two theories. The problem is that both theories are very solid and well-tested on their own right. A theory which tries to combine relativity and QM on a logical level is Branching Space-Time by Nuel Belnap.

* For axioms of special relativity, check: - Optical geometry of motion, a new view of the theory of relativity by A. A. Robb, 1911
- A theory of time and space by A. A. Robb
- The absolute relations of time and space by A. A. Robb, 1921
- Geometry Of Time And Space by A. A. Robb, 1936
- Orthogonality and Spacetime Geometry by Robert Goldblatt, 1987 (this is a first oder theory, so it is both complete and consistent - however it is not categorical
- Independent axioms for Minkowski space-time by John W. Schutz, 1997. This theory is of second order, so it suffers from the problems caused by the Gödel theorems.

** Check Quantum Logic by J. von Neumann (yes, the guy of the "Von Neumann Concept") and G. Birkhoff.

Comment Re:Then don't call it a theory, ya know? (Score 1) 284

Thanks you for supporting my point of view - you should create an account, then I could become a fan :)
However, I disagree with mathematics including physics. I consider mathematics as being a tool or even a language used by physiscs.
Disclaimer: I'm neighter a mathematician nor a physicist (I'm a logician.)

Comment Re:And when it fails this test too (Score 5, Informative) 284

Well, propositional logic can be proven to be consistent (there are no contradictions) AND complete (all true propositions can be proven out of the axioms), so can first order predicate logic (in the PhD dissertation of Gödel, 1929).

To construct arithmetic out of logic, we however need second order predicate logic. Gödel (1930, published 1931) showed that axiomatic systems in second order logic are either incomplete (true non-provable sentences can be constructed) OR they are inconsistent (containing contradictions).
Cloud

Yale Researchers Prove That ACID Is Scalable 272

An anonymous reader writes "The has been a lot of buzz in the industry lately about NoSQL databases helping Twitter, Amazon, and Digg scale their transactional workloads. But there has been some recent pushback from database luminaries such as Michael Stonebraker. Now, a couple of researchers at Yale University claim that NoSQL is no longer necessary now that they have scaled traditional ACID compliant database systems."

Comment Re:Is this any surprise? (Score 1, Interesting) 206

maybe if linux users were not just all anti-copyright thieves and pirates, [...]

Hi, I am a Linux user and I am anti-copyright and anti-"Intellectual Property" in general. But I have never stolen anything nor raided any ships. Oh, you mean illegal copying of software... Well, since I use Linux I do not need to make illegal copies, nor do I have the time for that because free software is released at such a fast rate that I have no hope to learn to use all of it in my lifetime. (Apologies for feeding the troll.)

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