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Comment This isn't about new hardware (Score 4, Insightful) 378

The problem is not newly-bought consumer electronics or legacy software. The problem is legacy hardware. I'm still using the Thinkpad I bought in 2006 (4:3 aspect ratio display). Luckily it's a 64-bit processor, but others have older 32-bit machines.

It's also not about the kernel -- Linux itself will support 32-bit architecture for a long while more, and most software will compile correctly on both 32-bit and 64-bit, though it will be less and less true as distributions stop their QA and you are left with only the upstream development team.

Of course, these old machines are pretty few, so it probably does make sense for Ubuntu to drop 32-bit packages. Other more enthusiast-targeted distributions will probably keep 32-bit support. In particular Gentoo compiles everything locally.

Comment "No surveillance or other purposes" -- really? (Score 5, Informative) 368

If the only goal was simply to provide low-power functionality, the coprocessor would be fully controlled by the operating system (ultimately, by the owner of the machine).

In fact, the main goal is to provide remote administration capabilities (what they call Intel Active Management Technology). In other words, the idea is to allow a remote administrator to take over the machine in a way that is independent of and invisible to the main operating system and processor. This serves a legitimate purpose in an "enterprise" environment (one person administers a large number of diverse machines) -- for example it allows taking back control of a cracked machine, or recovering critical data from memory after OS crashes. However, this feature is not useful for a privately administered single-user machine.

Finally, by definition a remote administration feature is a back door. This one is incredibly dangerous: a rootkit running on the coprocessor is entirely invisible to the operating system, has its own independent network access, and can monitor the disk, the memory and all other peripherals. In principle the remote management features must be activated via the System BIOS and you can set a password there, but really your only measure of safety against this back door is your trust that there are no bugs in Intel's code.

Why isn't Intel allowing you to replace the firmware? Because it's hard to ensure that the owner of the machine is the one initiating the firmware replacement. The real troubling point is that Intel isn't allowing you to disable this feature with a hardware switch. Hardware switches (jumpers on the motherboard) are a way of controlling the system available only to the physical owner of the machine. Having a hardware switch would satisfy both the enterprise and security-concious customers.

Comment Congress should fix it (Score 2) 63

Both the Patent law and Copyright law are in desperate need of fixing, and letting courts bumble their way around is not the way to go.

Current Patent law is drafted with the idea that you patent whole devices, at which point if you build something covered by patent without getting a license you should be liable for your "total profits". But today patents cover small bits in the device, and each device embodies thousands of patents. Courts (especially the Supreme Court) can say "Congress didn't think about that when it drafted the law, so we'll 'interpret' the language Congress actually wrote [total profits] to mean something that makes sense [the part of the profits which is attributable just to the infringed patent]. But this is a bad solution -- much better would be for Congress to change the law. At that time other urgent fixes (like the term of patents, the windfall rules for making out-of-patent and out-of-production rare drugs etc) can also be made.

Copyright law is similar: rather than hope courts will restrain themselves (lowering absurd damage verdicts like the Jammie Thomas case) or restrain Congress (how did Eldred v Aschroft do?) we need to get Congress to fix the copyright term at something reasonable (say 20 years, renewable with registration once).

Comment How can they correct this bias? (Score 4, Insightful) 304

And now that Google is aware of this, it should take some steps to correct this bias. As a significant source of information to the great masses, washed and unwashed, this will just perpetuate sterotypes and lies.

So you think that instead of reporting on the world as it is Google should, in their infinite wisdom, decide what the world should look like and then return search results with that in mind?

Moreover, how do you envision Google actually implementing your regime of censorship? Currently the lifetime risk of going to prison for a black US male is about 30%. By age 18, 30% of black men have been arrested. The typical white and black teenager do not have the same life experiences. So how are Google's algorithms supposed to decide when displaying the inequalities of our society is the right thing to do, and when doing so would be too upsetting to the user?

Comment Non-linearity at smaller scales (Score 3, Interesting) 146

I wish slashdot headlines weren't so definite. This is a single paper adding incrementally to our knowledge; it is not a survey article describing the joint understanding of all cosmologists.

For example, reading the paper, the galaxies hosting the supernovae in the sample had Cepheid--calibrated distances, in other words these are reasonably close objects (hence the reference to the local Hubble constant). While the paper discusses the possible effect of local motions of these 19 (!) galaxies, I don't think this discussion is sufficient. These proper motions are a more likely effect than issues with the CMB.

Comment Re:Contents of the 200TB proof (Score 5, Insightful) 143

Sorry, the system ate my "less than" signs. Here's a corrected version.
  1. Consider the integers between 1 and 7285. To each integer i assign a boolean variable P_i. These variables encode the partition of these integers into two classes (think of P_i as encoding the statement ""the integer i belongs to the first class").
  2. Now let $a,b,c$ be a Pythagorean triple (a^2+b^2=c^2 and each is between 1 and 7285). Construct the boolean expression Q_{a,b,c} = (P_a & P_b & !P_c) || (P_a & !P_b & P_c) .." (disjunction of 6 clauses each being a conjunction of three terms) describing the 6 ways in which a triple can be non-monochromatic). So Q_{a,b,c} encodes the assertion "the integers a,b,c are not in the same class" by writing out the 6 ways in which a,b,c can belong to two classes without all belonging to the same class).
  3. Finally, the claim "every triple is not monochromatic" is obtained by taking the conjuction of the Q_{a,b,c} over all triples (a,b,c) as above. It's a huge boolean expression and the goal is to show that it always evaluates to FALSE (in other words, that for any boolean assignment to all the P_i), the huge conjugation always takes the values.
  4. The proof works by manipulating this boolean expression: it has 200TB of instructions on how to manipulate this huge boolean expressions step-by-step in ways that obviously don't change its truth value, so that at the end one of the clauses in the conjunction simply reads "FALSE", making the whole expression indeed universally false. A computer program discovered this list of manipulations, and a separate (much simpler) program can easily verify that the manipulations are of the right kind (they don't change the truth value) and that at the end of the manipulation you get a clause saying FALSE.

Comment Contents of the 200TB proof (Score 2) 143

On topic, what is the content of this 200tb proof? Is that just a text file where each character is a bit? How many libraries of congress is this proof?

Consider the integers between 1 and 7285. To each integer i assign a boolean variable P_i. These variables encode the partition of these integers into two classes (think of P_i as encoding the statement ""the integer i belongs to the first class").

Now let $a,b,c$ be a Pythagorean triple (a^2+b^2=c^2 and 1

Finally, the claim "every triple is not monochromatic" is obtained by taking the conjuction of the Q_{a,b,c} over all triples (a,b,c) as above. It's a huge boolean expression and the goal is to show that it always evaluates to FALSE (in other words, that for any boolean assignment to all the P_i), the huge conjugation always takes the values.

The proof works by manipulating this boolean expression: it has 200TB of instructions on how to manipulate this huge boolean expressions step-by-step in ways that obviously don't change its truth value, so that at the end one of the clauses in the conjunction simply reads "FALSE", making the whole expression indeed universally false. A computer program discovered this list of manipulations, and a separate (much simpler) program can easily verify that the manipulations are of the right kind (they don't change the truth value) and that at the end of the manipulation you get a clause saying FALSE.

Comment Re:Proof? (Score 5, Informative) 143

They proved that in every partition of the positive integers into two classes, one class contains a solution to the equation $a^2+b^2 = c^2$. The method of proof is by showing this is already two for any partition of the interval {1,2,...,7,825} into two classes.

This is not entirely surprising; probably there will eventually be quantitative bounds showing that if you colour the integers in {1,2,...,N} in two colours then there are at least f(N) monochromatic Pythagorean triples for some increasing function f(N). Then 7,825 is the first N where f(N)>0, that's all.

I do agree with you that Graham probably expected a proof of the quantitative type rather than a computer search, because many other Ramsey theory problems have quantitative solutions, but there's nothing wrong with starting with a computer search.

Comment Computer-assisted proofs are proofs (Score 2) 143

Well, part of the argument is proving that (if implemented correctly) the algorithm actually solves the problem. But in fact this part is redundant -- because what the computer does is actually write out a proof of the theorem.

The point is that while coming up with a proof takes work or ingenuity, verifying the correctness of an proposed proof (written in sufficient detail) is purely mechanical. In other words, you don't need to believe or check anything the researchers have done. You simply need to take the output of their program and use a proof-checker to verify that this output is a valid proof.

For many combinatorial theorems this is the way of the future, and while the submitted may be unsatisfied by a proof which doesn't provide intuition, isn't that better than no proof at all?

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