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Comment Re:Remember when (Score 1) 36

You missed "it's faster than C!! Well, it will be faster than C in the future! Well, it will be faster than C once we have JIT. Well, it will be faster than C once JIT actually optimizes things as promised... Any day now..."

"The year is 2017, and Oracle launches the last of America's deep database probes. After his systems are unexpectedly frozen by garbage collection, Solaris 12 and its pilot Captain Larry 'Buck' Ellison are blown out of their trajectory into an orbit which freezes his life support systems, and returns Larry Ellison to Earth five-hundred years later."

Comment Re:One obvious improvement (Score 1) 144

That old story again. You know what the + operator does? It adds two things together. How it does that is really none of your business.

You probably think that you know what happens when you write x + y. Well, you don't. It all depends on the type: if x and y are integer, an integer addition instruction is used. If they are floating point a floating point addition instruction is used. And if one is integer and the other floating point there is first a conversion, and then a floating point addition. If one is a pointer and the other an integer, there is a multiplication, an integer addition, and perhaps pointer normalisation (only on obscure architectures). So that simple '+' already means a lot of different things. Given you already have to deal with all that, I really don't see the problem for allowing addition for user-defined types as well, like BCD, or bignum, or complex, or matrix, or whatever.

Comment Re:Whitespace takes the most space (Score 3, Informative) 144

There's nothing to discuss since any algorithm can be written in any turing complete language.

There's plenty to discuss, since the ease with which you can express yourself matters greatly in any practical sense. However, the progress we have actually made in this area is not nearly as impressive as one might hope - new languages mostly bring us the same thing, but with slightly different syntax. Real breakthroughs are very, very rare. Remember the 4GL initiative from Japan in the nineties? Still waiting for that killer language... The closest I've seen is the Wolfram language. Maybe that's the way forward: a massive support library and huge, online databases.

As for Turing machines... On a machine with finite memory, all states the machine can be in can be enumerated, and each state always leads deterministically to a single next state. Since the total number of states is finite (very large, but finite), this means that at some point it must either return to a previous state, or halt. If it returns to a previous state, it will then continue to loop forever (since each state deterministically leads to a single next state). Thus, if you have the capacity to track state changes for long enough, you will be able to determine if a program will halt or not.

And yet, there's Turing's proof. Why the discrepancy? Well, simple: a Turing machine has an infinite tape, and can therefore produce not a finite, but an infinite number of states. Any computer we have in the real world does not have infinite memory, and is therefore not a Turing machine. To be considered Turing-complete, a language must be able to simulate a Turing machine - and that's actually impossible, since it can never meet the "infinite tape" requirement. You might claim that "any algorithm can be expressed in any Turing complete language", but since we don't have any, that's really a moot point, and we would perhaps be wiser to focus on other aspects of the language rather than a theoretically impossible, and perhaps even undesirable feature.

Your move, AC ;-)

Comment Beer? (Score 1) 157

BSD is free like the Grimm fairytales.

Sometimes you're shared the stories and you're allowed to reshare them, e.g. from Gutenberg. Sometimes you're not. E.g. from Disney.

BSD gives you the freedom to take it, modify it, distribute it and not allow the recipient the same benefit.

"Free as in beer" doesn't imply the knowledge nor right to start a brewery and produce your own. It's ridiculous to say Linux is free as in beer.

Comment Re:Catastrophic man-made global warming (Score 2) 273

Perhaps, perhaps not. Venus is still very poorly understood. In its high temperature environment its conditions are largely self-sustaining (preventing the sequestration of CO2 in rock), although it's also unstable, prone to broad temperature and pressure swings. It also appears to have undergone a global resurfacing event about 300-500mya, if that gives a clue as to how unstable the planet as a whole is. ;) We don't know what caused it, or really anything about it. Part of the planet's properties are now a result of it having lost its water rather than being a cause, such as its hard crust. Obviously its lack of a magnetic field is responsible for its loss of water, but we don't know exactly when or why it disappeared (there are of course theories... I had always just assumed it was the slow rotation rate, but the last research I read suggested that not enough to account for it). Other issues as to how Venus ended up as it did may be related to size - although it's only a bit smaller than Earth, that may be the initial factor that set its fate in motion - for example, its lithosphere in general appears to be thicker and higher viscosity on Earth, which could have hindered or prevented plate tectonics, and thus subduction of carbonates.

Either way, it's a mess now at the surface (though rather comfy ~55km up ;) ). And I'm not so sure I buy into some of the proposed ways to fix it (terraforming). For example, some have suggest mass drivers ejecting the atmosphere. Let's just say you can pull it off, and then you start building oxygen in the atmosphere - what happens next? The crust is something like 7-9% FEO; it's going to rust away whatever oxygen you make in short order.

Interestingly, I'd argue that this is possibly the salvation to Sagan's airborne-microbe concept for terraforming Venus. The main criticism is that if you engineered some sort of carbon-sequestering microbe on Venus (or artificial equivalent), you'd end up with a deep surface layer of graphite surrounded by some hugely hot, dense oxygen layer, and the atmosphere would explode. But that would never happen; at Venus surface temperatures and pressures, the surface rocks would rust away the oxygen as fast as it was created, even in tiny quantities, with the wind blowing the dust around to collect at low/eddy areas. So you're laying down bands of carbon and iron oxide as you burn through the planet's iron buffer. Where have we seen this before? Right, Earth, ~2,3 billion years ago, banded iron formations. Just like on Earth, you'd eventually burn through the iron and start to accumulate oxygen. But by then the graphite is already underground, buried in iron dust.

It's not a fast process. But it has precedent. Microbes already rusted at least one planet, and that planet's surface conditions weren't nearly as favorable for rusting as Venus's.

Comment Re:Catastrophic man-made global warming (Score 1, Troll) 273

I don't know how China managed to melt so much arctic ice, leading to the absurd situation that just a couple days before the winter solstice this year I went on a hike through the snowless mountains in Iceland among chirping songbirds digging for worms. All I have to say to China about this is: Best. Conspiracy. Ever. Well played, China. Well played.

Comment Re: Bradley Manning needs a HOSTS file (Score 2) 382

Yes there is. It's not a right-left test, but there's a near-perfect match between gender and specific neurological features. In a higher than expected number by chance, people who think they are mentally female are female in structural and functional studies. Likewise, people who believe themselves male have a male brain.

I try not to get too annoyed at dogmatic statements, but unless I specifically defer, I have a comprehensive archive of published literature from high-standing sources. Don't rip on me unless you know either my interpretation is wrong (it happens) or you plan on publishing a peer-reviewed rebuttal on each particular of relevance.

The first of those has happened a few times. Let's see if you can bring it up into double digits. Feel free, but remember that you're dealing solely with article facts and my interpretation. Where I used other sources, pick any peer-reviewed paper that covers the same basic aspect of brain development concerned (i.e. neuron type is indicated by chemical transmitter, it is not hardwired into the genome. Doesn't matter if it is the one I used or not. Falsify it. Better yet, falsify it and get the scientist or magazine to retract it for further work.

Ok, you should now be at the point where you accept the data sets I used. That just leaves two options. If the seat of the mind is in the brain, then a female brain must have a female mind, regardless of Y chromosomes, appendages and birty certificate.

The only other option is to falsify that, to argue that the mind is independent of brain. If you choose this, please choose to announce it at a medical school outside the brain surgery department after a very taxing practical, shortly before exams. Contrary views are nothing to worry about.

Finally,You can just let the basis be, the chain of reasoning be, but then you have to accept the conclusion.

Let me know your preference.

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