Want to read Slashdot from your mobile device? Point it at m.slashdot.org and keep reading!

 



Forgot your password?
typodupeerror
×

Submission + - Why David Deutsch's New Theory of Reality is Deeper Than Quantum Mechanics

KentuckyFC writes: In 1948, the Bell Labs mathematician and engineer Claude Shannon published The Mathematical Theory of Communication (pdf). In it, he laid out the basic process of communication and formally introduced ideas such as information, the role of transmitters and receivers as well as the idea of a channel and its capacity to carry information. This theory now forms the basis of all digital communication so it's no exaggeration to say that it has been hugely influential. By contrast, no equivalent theory exists for quantum information, despite decades of work by quantum theorists. That could all change now thanks to the work of David Deutsch, a theoretical physicist, who has developed a theory that links classical and quantum information using a deeper theoretical framework. Deutsch's new approach is called constructor theory and it turns the conventional approach to physics on its head. Physicists currently ply their trade by explaining the world in terms of initial conditions and laws of motion. This leads to a distinction between what happens and what does not happen. By contrast, Deutsch’s new fundamental principle is that all laws of physics are expressible entirely in terms of the physical transformations that are possible and those that are impossible. In other words, the laws of physics do not tell you what is possible and impossible, they are the result of what is possible and impossible. So reasoning about the physical transformations that are possible and impossible leads to the laws of physics. He uses this approach to develop a number of principles that all physical laws must follow, both those that are known and those that are unknown. Consequently, constructor theory must be deeper than all known physical theories such as quantum mechanics and relativity. He draws an analogy between this and conservation laws which are deeper than all other physical laws which must follow them. It's too early to say what impact Deutsch's new approach will have. But he has a spectacular record in physics having been a pioneer of quantum computation in the 1980s and one of the chief exponents of the multiverse, both of which have become mainstream ideas.

Submission + - Physicists Prove Surprising Rule of Threes (simonsfoundation.org)

An anonymous reader writes: More than 40 years after a Soviet nuclear physicist proposed an outlandish theory that trios of particles can arrange themselves in an infinite nesting-doll configuration, experimentalists have reported strong evidence that this bizarre state of matter is real.

Comment Re:Google is dropping XMPP and Talk/Chat anyway (Score 1) 121

Good point on latency, I forgot about that. What's worse is that streaming media can readily compensate for latency, as long as it's reasonably consistent. On the other hand, I work from home a fair amount, sometimes with vnc, sometimes with remote X. I'm a heck of a lot more sensitive to latency.

But even if you regulate Netflix like a content provider, it still leaves Comcast jealous, because none of the effects of that regulation wind up in Comcast's pockets. The reality is that Comcast doesn't want to be an ISP, they want to be a content provider, because that's where they're from. Being an ISP was just an "opportunity" they were well poised to take advantage of, with their infrastructure. Only problem is that in the real world, instead of Comcast's dream work, the "opportunity adder" is bigger than their core business. They're working really hard to impose their dream on reality, and since they own the pipes, they're getting away with it.

Once upon a time there was talk of Internet2 - I believe it hooks some universities, national labs, and businesses together. Part of me wonders if at some point corporate US really will manage to turn the internet into a series of walled gardens, and we'll be back to the days of modems, bang-paths, and line-of-sight hacks.

Comment Re:Google is dropping XMPP and Talk/Chat anyway (Score 1) 121

Go ahead and choose your walled garden, I won't stop you.

But from where I sit, it looks like everything that connects to the home is going to walled gardens, and open as an option is fading away.

Serious proposal: Allow a "fast lane" by any/all ISPs. They've got such a hard-on for a fast lane that they're going to keep buying legislators until they get one. Then place a limit on it. The fast lane can only be X times faster than the "neutral net lane", and NO traffic shaping or limits are allowed on that lane, other than being 1/X the speed of the fast lane. Plus X needs to be a legally asserted and testable value.

Comment Real world games (Score 1) 1

Balderdash, Apples to Apples, Pit all work for larger groups.

For slightly smaller groups, Dominion

For 3 or 4, Settlers or Dominos

And of course there is a whole range of games for all group sizes using regular playing cards.

Comment Re:Skipping mere "technical problems" (Score 1) 165

Issues like this are why Asimov sold a lot of books, and why the Three Laws come up whenever robots are discussed. He came up with a reasonable, minimal code of conduct, and then explored what could possibly go wrong.

I don't remember him writing about your type of situation, which is rather odd when you think about it, because that scenario is rather obvious. But his stories often lived in the cracks where it was really hard to apply the Three Laws. Two examples that come to mind, off the top of my head are:
1 - The Powell and Donovan story at hyper-base, where the act of going through hyperspace "temporarily" sort-of killed the passengers, causing the robot directing the ship all sorts of distress and neuroses.
2 - The robots who were taught the idea of preferentially applying the First Law in favor of the "best humans", and going on to logically decide that they were indeed the "best humans", and therefore to be favored above those organic beings that created them.

Comment Skipping mere "technical problems" (Score 1) 165

Since it's all conjecture, really fiction, let's drop back to Asimov for a moment.

1 - A robot may not harm a human being, or through inaction allow a human being to come to harm.

What is a "human being"? Is it a torso with 2 arms, 2 legs, and a head? How do you differentiate that from a manniquin, a crash-test dummy, or a "terrorist decoy"? What about an amputee missing one or more of those limbs? So maybe we're down to the torso and head?? What about one of those neck-injury patients with a halo supporting their skull? Does that still pass visual muster as a "head"? What about a dead body then, that has a head, 2 arms, and 2 legs? Or if you've included temperature sensing, the dead body of a sick person who had a fever and is, some time later, still passing through the normal human temperature range.

Silly, yes. Absurd, yes. But before you can consider any code of conduct with respect to a human being, you have to first identify that human being AS a human being.

Pretend we get past that, then we can start talking about "harm", and trying to algorithmically define that.

These are all things we take for granted, having been born as human beings, raised by human beings, and spent years doing so. In most parts of the world it takes something like 18 years of experience to quit being a "child", an apprentice human being, and be considered autonomous in your own right. In that time, we have all both harmed and been harmed by other human beings, though thankfully generally on a lesser scale.

Each of us represents a lot of training and experience, which we frequently neglect, often calling it "common sense", sometimes making the observation that common sense is in fact uncommon. At some point we set about contemplating matters of (at some level) philosophy, such as this one.

But it takes us something approaching 18 years to learn the technical aspects. I know we can program machines and give them some amount of information "at birth", but I think we are underestimating the difficulty and value of those 18 years and overestimating our technical prowess. We're a long way from teaching machines philosophy.

Perhaps the best thing about arming drones now is that in a way it's like arming young children, and they generally try to do what their parents tell them to do. If machines became moral, and could decide what to do for themselves, we might not like those decisions. Forget the nightmare scenarios, think of the benign scenario taken to the nightmare, like "With Folded Hands."

Final thought... At one point, Asimov suggested that the 3 Laws were actually pretty decent conduct suggestions, even for people. (I would certainly question the relative priority of #2 and #3 in general life for real people, of course.)

Comment Re:Chlorrophyll makes a big assumption (Score 3, Interesting) 46

ISTR that chlorophyll is essentially a "voltage doubler", basically for red light. (Leaves are green because they use the red, and discard/reflect the green.) If you consider red to be between 600nM and 700nM, then a little more UV than we get might deliver enough content between 300nM and 350nM to be used directly for photosynthesis. I wonder how much UV would be needed to bypass the doubler, and if that would be too much for life, in general. Of course that would mean a hotter sun than ours, and I've more recently heard more about searching around red dwarves, where the leaves would more likely look black.

Submission + - A Star Cluster Thrown Out Of Galaxy At Hypervelocity Discovered

William Robinson writes: According to these reports, A globular cluster of several thousand stars, compressed into a space just a few dozen light years apart, is thrown out of galaxy M87. The cluster, named as HVGC-1, is traveling at a rate of 2 million miles per hour. The discovery was made by Nelson Caldwell of the Harvard-Smithsonian Center for Astrophysics and his team while studying the space around the supergiant elliptical galaxy M87. Caldwell and colleagues think M87 might have two supermassive black holes at its center. The star cluster wandered too close to the pair, which picked off many of the cluster’s outer stars while the inner core remained intact. The black holes then acted like a slingshot, flinging the cluster away at a tremendous speed.

Comment Re:you mean vertically? (Score 2) 110

Absolutely not. There is still significant gravity in space - it falls by inverse-square law, after all. In LEO the force of gravity is practically undiminished. For a "long" structure you'll soon find out that vertical does exist, because that's the way the long axis of that structure will be oriented. Look up "gravity gradient stabilization".

Of course that discribes the axis toward/away from the Earth. I don't know if there is any preferred direction beyond that, but it would surprise me if extended objects don't feel some force related to the direction of their orbits. Basically I'm sure of up/down, and have a feeling that fore/aft can be differentiated from port/starboard. I'd have to agree that North/South/East/West are meaningless - at least for electrically neutral structures.

Submission + - SpaceX Posts Damaged Video Of Falcon 9 First Stage Splashdown (nbcnews.com)

rasmusbr writes: SpaceX has posted video from a camera mounted on the Falcon 9 rocket's first stage as the rocket stage attempted a soft splashdown on the ocean surface on April 18, after launching a resupply mission to the International Space Station. The powered splashdown was a test of the Falcon 9 first stage's ability to decelerate and land after launch, a crucial step toward a reusable first stage.

The video bitstream is damaged and SpaceX has spent a week trying to repair it. They now turn to the public for help.

Submission + - Wonder-Material Graphene Could Be Dangerous to Humans and the Environment (gizmag.com)

Zothecula writes: It’s easy to get carried away when you start talking about graphene. Its properties hold the promise of outright technological revolution in so many fields that it has been called a wonder material. Two recent studies, however, give us a less than rosy angle. In the first, a team of biologists, engineers and material scientists at Brown University examined graphene’s potential toxicity in human cells. Another study by a team from University of California, Riverside’s Bourns College of Engineering examined how graphene oxide nanoparticles might interact with the environment if they found their way into surface or ground water sources.

Comment Re:Am I reading this right (Score 0) 172

You could look at them as shills, or you could look at them as putting their money where their mouths are. The saw a threat and are doing what they can within our system to handle it.

So when government does it, it's either inefficient or a boondoggle, but when a company does it, attempting to inform about the threat they're trying to solve makes them a shill. As long as they're above-board about their position, and clear and honest with their science, I see no problem.

Slashdot Top Deals

He has not acquired a fortune; the fortune has acquired him. -- Bion

Working...