Mapou

I don't think you get it. A block universe in which nothing happens cannot possibly exist since it is clearly falsified. We observe change, do we not? So speaking of loops within a block universe is like arguing about how many angels can dance on the head of a pin. Is it me, or do other people go out of their way to be illogical?

I am not sure exactly what you explained. First off, relativity, like Newtonian mechanics, is a classical physics theory. I am not aware of any such thing as non-classical relativity. So why even say classical relativity? At the very least, it is redundant.

Second, of course the universe is probabilistic, a fact that falsifies both relativity and Newtonian physics.

Third, the universe is probabilistic precisely because time cannot change. Why? Because, since time is not a variable and is thus non-existent, the universe cannot calculate precise temporal durations. Thus, in order to properly conserve energy, it is forced to use the next best thing: probability.

Fourth, this has everything to do with article since entropy, as explained in the text books, assumes the passage of time and thus a time direction or arrow. Since time is abstract, it follows that an arrow of time is imaginary. As a result, it makes perfect sense that one cannot reverse entropy. Or anything else, for that matter.

The purpose of my comment was to get people to think and to stop accepting everything they hear on face value. If time cannot change, which is trivially shown to be true (changing time is an oxymoron because it is circular), then all the so-called time-travel conjectures by famous physicists like Kip Thorne, Stephen Hawking, David Deutsch, and many others, are pure crackpottery.

Time cannot change by definition. Nothing can move in spacetime for the same reason. This is why the late Sir Karl Popper (of falsifiability fame) once compared spacetime to Parmenides' block universe and called it "Eintein's block universe in which nothing ever happens". (Source: Conjectures and Refutations).

In his textbook, "Relativity From A to B", renown relativity expert Robert Geroch wrote, "There is no dynamics within space-time itself: nothing ever moves therein; nothing happens; nothing changes." Very few physicists know this but it's the truth, a nasty little truth for some, but the truth nonetheless.

In conclusion, any talk of time travel in any direction (forward or backward) is pure crackpottery. There is only the NOW, the ever changing present. Don't mod me down because you have a different opinion. Incessant propaganda and sci-fi movies like Star-Trek have duped a lot of people. Just think about it and figure it out on your own.

Nothing can move in spacetime.

I think the voting problem is a serious one. Apparently, only a minority of readers and posters vote and they seem to have a gang mentality that works like this: "If I don't like you, I'll vote you down regardless of what you write." This sucks the big one.

The same problem is happening on every site where voting is allowed. There is usually a loud, highly emotional and political minority with a lot of time on their hands that invariably takes over and impose a fascist dictatorship on the rest of the community. Digg, Slashdot and Wikipedia are cases in point. I wish there was a way to motivate a greater percentage of readers to take part in the voting process.

Another problem is that a lot of people receive updates via RSS news readers and I suspect that most go directly to the link and rarely check the comments or attempt to vote. YC needs a way to entice people to visit the site and incorporate the number of times a link is clicked to the formula that computes the popularity value of the story. Just one man's opinion.

In my opinion, that's exactly what they are doing. They have adopted a paralllel computing model (multithreading) that is known to be a pain in the ass to program. So far, they have no plans to change the model. They either don't know how or they are stuck in a rut because they need to maintain compatibility with legacy systems. They are in a state of panic right now, spending money left and right trying to find a solution that does not exist for their chosen model. This is a great opportunity for some other company (or a startup) to come on the scene and make a killing.

I disagree that a kick-ass multicore processor is not a product, especially if you can get $500 for every one that comes out of the fab.

Are you kidding me? Once cheap massive parallelism becomes the norm, you're going to see amazing applications for the average person, especially intelligent programs. For examples, intelligent answering systems, voice recognition, handwriting recognition, face recognition, dog walker, housekeeping robots, portable language translators, self-driving vehicles, sentries, etc... The possibilities are endless.

Which parallel programming startups are you referring to? Sure, the established companies are adapting their exisiting tools to address the new multicore processors but I am not aware of any new parallel programming tools startups that failed. Most of the multicore processor startups are still around. Tilera, Ambric, Pico, etc... are still hanging in there. Pico is doing great. Israel's Plurality is just now beginning to get recognition for its self-balancing 64 to 256-core hypercore chip.

My point is that there are very few new multicore startups and I think that the reason is not that too many of them failed in the past but that only a few have had anything really interesting or disruptive to offer. It remains that there is a big problem that needs to be solved right now and whoever solves it will grab a lion share of the CPU market in this century.

Yeah, but this is a different ball game. The big players have an Achilles' heel. They are clueless as to what the future holds for multicore processors and they don't seem close to a solution. Parallel programming is a pain in the ass. There is even panic in the air because the big vendors have no real idea how to proceed. The solution is out there though. Some unknown startup may sneak behind them and steal the pot of gold while they're busy fighting amongst themselves.

Not $100k, of course. But I think $5 or $6 million dollars could do it. For that, you'd get a scalable, self-balancing 16 or 32-core processor compatible with existing motherboards and chip sets, visual dev tools using multi-touch screens, and a fully built computer with an extensible parallel OS including a good set of device drivers.

The whole engineering/design phase would take about two years. After that, you enter the marketing and production phase which will require several busloads of dough but that's not my department.

I see what you're saying and I think you're probably right. But if you can design and build a kick-ass multicore processor that blows everyone else out of the water in terms of performance, energy efficiency and ease of programming, it makes sense to give all your dev tools away for free. Heck, you could even throw in an OS and a nice browser for good measure.

I realize that I'm biased since I happen to think that multicore design is the most exciting thing out there. In my opinion, whoever solves the multicore/parallel programming problem will dominate computing for the rest of the century. The rest of the industry, including Intel, IBM, AMD, APPLE, etc... would flock like migratory birds to come and worship at your feet.

Why does almost every startup have to be a social web site or some other web app? The web is surely not the only thing in the hacker universe, is it? The biggest opportunities in computing today are in parallel programming tools and multicore architecture and design. How come nobody seems to care about those things?

I note that your Phd dissertation was titled, "Prefetch mechanisms by application memory access pattern". Surely this qualifies you for all sorts of computing projects.

Bravo. You're the only commenter who had something interesting and intelligent to say about the article. The others are jumping up and down and foaming at the mouth. LOL. In the future, when parallel programming becomes easy and powerful parallel computers become the norm, we will find that most applications are significantly more parallel than sequential. The coming intelligent programs will have huge numbers of sensors (visual, auditory, tactile, etc...) and effectors. These naturally call for massive parallel processing.

You Turing worshippers are so full of hate. You sound like somebody just blasphemed against your two-bit god. LOL. Too bad for you that the parallel programming crisis is about to bring Turing down from his pedestal. Then you'll shut the hell up. I have a wide grin on my face just thinking about it.

Money always talks and no chicken-shit cult of propeller heads can stop that. LOL.

Crank or not, his stuff on parallel programming makes sense.

You're kidding me? The computing world is about to witness the most drastic paradigm shift in its history. After all is said and done, the threaded or sequential process programming model will not only be superseded, we will kick ourselves in the ass for having been so stupid for so long.

I am not sure why the drug dealers think that these delivery crafts have to have human pilots on board. With the kind of money that these guys have, it would be relatively easy to implement a self-piloting craft that can go anywhere.

Why put up this strawman? There is nothing in the article about either the limits of computation or a mathematical proof. Pretty much all it says is that the Turing sequential (or algorithmic) conmputing model is inadequate and I agree. We need a better model.