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Comment Re:Just another step closer... (Score 1) 205

You make good points. However, I think you're somewhat mischaracterizing the modern theories that include parallel universes.

So long as we use the real physicists definitions and not something out of Stargate SG1, those parallels will always remain undetectable. SF writers tell stories about interacting with other universes - physicists define them in ways that show they can't be interacted with to be verified.

(emphasis added) Your implication is that physicists have invented parallel universes, adding them to their theories. In actuality, parallel realities are predictions of certain modern theories. They are not axioms, they are results. Max Tegmark explains this nicely in a commentary (here or here). Briefly: if unitary quantum mechanics is right (and all available data suggests that it is), then this implies that the other branches of the wavefunction are just as real as the one we experience. Hence, quantum mechanics predicts that these other branches exist. Now, you can frame a philosophical question about whether entities in a theory 'exist' or whether they are just abstractions. But it's worth noting that there are plenty of theoretical entities that we now accept as being real (atoms, quarks, spacetime, etc.). Moreover, there are many times in physics where, once we accept a theory as being right, we accept its predictions about things we can't directly observe. Two examples would be: to the extent that we accept general relativity as correct, we make predictions about the insides of black holes, even though we can't ever observe those areas. To the extent that we accept astrophysics and big-bang models, we make predictions about parts of the universe we cannot ever observe (e.g. beyond the cosmic horizon).

An untestable idea isn't part of science.

Indeed. But while we can't directly observe other branches of the wavefunction, we can, through experiments, theory, and modeling, indirectly learn much about them. We can have a lively philosophical debate about to what extent we are justified in using predictions of theories to say indirect things are 'real' vs. 'abstract only'... but my point is that parallel realities are not alone here. Every measurement we make is an indirect inference based on limited data, extrapolated using a model we have some measure of confidence in.

Occam's Razor ...

Occam's Razor is frequently invoked but is not always as useful as people make it out to be. If you have a theory X and a theory X+Y that both describe the data equally well, then X is better via Occam's Razor. But if you're comparing theories X+Y and X+Z, it's not clear which is "simpler". You're begging the question if you say "Clearly X+Y is simpler than X+Z! Just look at how crazy Z is!" More specifically: unitary quantum mechanics is arguably simpler than quantum mechanics + collapse. The latter involves adding an ad-hoc, unmeasured, non-linear process that has never actually been observed. The former is simpler at least in description (it's just QM without the extra axiom), but as a consequence predicts many parallel branches (it's actually not an infinite number of branches: for a finite volume like our observable universe, the possible quantum states is large but finite). Whether an ad-hoc axiom or a parallal-branch-prediction is 'simpler' is debatable.

Just about any other idea looks preferrable to an idea that postulates an infinite number of unverifiable consequents.

Again, the parallel branches are not a postulate, but a prediction. They are a prediction that bother many people. Yet attempts to find inconsistencies in unitary quantum mechanics so far have failed. Attempts to observe the wavefunction collapse process have also failed (there appears to be no limit to the size of the quanum superposition that can be generated). So the scientific conclusion is to accept the predictions of quantum mechanics (including parallel branches), unless we get some data that contradicts it. Or, at the very least, not to dismiss entirely these predictions unless you have empirical evidence against either them or unitary quantum mechanics itself.

Comment Re:Can't have it both ways (Score 1) 330

I disagree. Yes, there are tensions between openness/hackability/configurability/variability and stability/manageability/simplicity. However, the existence of certain tradeoffs doesn't mean that Apple couldn't make a more open product in some ways without hampering their much-vaunted quality.

One way to think about this question to analyze whether a given open/non-open decision is motivated by quality or by money. A great many of the design decisions that are being made are not in the pursuit of a perfect product, but are part of a business strategy (lock-in, planned obsolescence, upselling of other products, DRM, etc.). I'm not just talking about Apple, this is true very generally. Examples:
- Having a single set of hardware to support does indeed make software less bloated and more reliable. That's fair. Preventing users from installing new hardware (at their own risk) would not be fair.
- Similarly, having a restricted set of software that will be officially supported is fine. Preventing any 'unauthorized' software from running on a device a user has purchased is not okay. The solution is to simply provide a checkbox that says "Allow 3rd party sources (I understand this comes with risks)" which is what Android does but iOS does not.
- Removing seldom-used and complex configuration options from a product is a good way to make it simpler and more user-friendly. But you can easily promote openness without making the product worse by leaving configuration options available but less obvious (e.g. accessed via commandline flags or a text config file).
- Building a product in a non-user-servicable way (no screws, only adhesives, etc.) might be necessary if you're trying to make a product extremely thin and slick.
- Conversely, using non-standard screws, or using adhesives/etc. where screws would have been just as good, is merely a way to extract money from customers (forcing them to pay for servicing or buy new devices rather than fix old hardware).
- Using bizarre, non-standard, and obfuscated file formats or directory/data-structures can in some cases be necessary in order to achieve a goal (e.g. performance). However in most cases it's actually used to lock-in the user (prevent user from directly accessing data, prevent third-party tools from working). E.g. the way that iPods appear to store the music files and metadata is extremely complex, at least last time I checked (all files are renamed, so you can't simply copy files to-and-from the device). The correct solution is to use open formats. In cases where you absolutely can't use an established standard, the right thing to do is to release all your internal docs so that others can easily build upon it or extend it.

To summarize: yes, there are cases where making a product more 'open' will decrease its quality in other ways. But, actually, there are many examples where you can leave the option for openness/interoperability without affecting the as-sold quality of the product. (Worries about 'users breaking their devices and thus harming our image' do not persuade; the user owns the device and ultimately we're talking about experience users and third-party developers.) So, we should at least demand that companies make their products open in all those 'low-hanging-fruit' cases. We can then argue in more detail about fringe cases where there is really a openness/quality tradeoff.

Comment Re:n = 1.000000001 (Score 3, Informative) 65

I'm somewhat more hopeful than you, based on advances in x-ray optics.

For typical x-ray photons (e.g. 10 keV), the refractive index is 0.99999 (delta = 1E-5). Even though this is very close to 1, we've figured out how to make practical lenses. For instance Compound Refractive Lenses use a sequence of refracting interfaces to accumulate the small refractive effect. Capillary optics can be used to confine x-ray beams. A Fresnel lens design can be used to decrease the thickness of the lens, giving you more refractive power per unit length of the total optic. In fact, you can use a Fresnel zone plate design, which focuses the beam due to diffraction (another variant is a Laue lens which focuses due to Bragg diffraction, e.g. multilayer Laue lenses are now being used for ultrahigh focusing of x-rays). Clever people have even designed lenses that simultaneously exploit refractive and diffractive focusing (kinoform lenses).

All this to say that with some ingenuity, the rather small refractive index differences available for x-rays have been turned into decent amounts of focusing in x-ray optics. We have x-rays optics now with focal lengths on the order of meters. It's not trivial to do, but it can be done. It sounds like this present work is suggesting that for gamma-rays the refractive index differences will be on the order of 1E-7, which is only two orders-of-magnitude worse than for x-rays. So, with some additional effort and ingenuity, I could see the development of workable gamma-ray optics. I'm not saying it will be easy (we're still talking about tens or hundreds of meters for the overall camera)... but for certain demanding applications it might be worth doing.
Image

Gubernatorial Candidate Wants to Sell Speeding Passes for $25 825

If Nevada gubernatorial candidate Eugene "Gino" DiSimone gets his way, $25 will buy you the right to drive up to 90mph for a day. DiSimone estimates his "free limit plan" will raise $1 billion a year for Nevada. From the article: "First, vehicles would have to pass a safety inspection. Then vehicle information would be loaded into a database, and motorists would purchase a transponder. After setting up an account, anyone in a hurry could dial in, and for $25 charged to a credit card, be free to speed for 24 hours."

Comment Geotagging isn't the problem (Score 1) 175

The real problem is that people are uploading their private photos to public places in the first place. It's already an invitation to crime, stalking, and government and business interference in private affairs. Why have people abandoned one of our most cherished rights so easily?

Sure, if you must upload pictures of you getting drunk or your new gadget at least strip the tags, but how about only sharing it with your friends using a more private method instead?

Social Networks

Best Alternatives To the Big Name Social Media? 451

rueger writes "Over a couple of years I have actually found Facebook pretty useful and/or entertaining. It has certainly allowed me to stay connected with a lot of people with whom I otherwise would have lost track, and for all its weaknesses it was handy for sharing links and such. This week, though, the privacy escapades have pushed me (and a lot of other people) over the edge. If Twitter's 140 characters aren't enough, LinkedIn is too business-oriented, MySpace too ugly, and Buzz — does anyone even use Buzz? What social media options are out there for all of those non-uber-techy folks?"
Wireless Networking

A Wireless Hotspot For Your Car — Why Not? 135

nk497 writes "UK mobile operator 3 has unveiled a wireless hotspot for cars. It's essentially a repackaged version of their MiFi wireless router, which lets users create their own wireless hotspot using the 3G network. While drivers will hopefully steer away from using the web at the wheel, 3 predicts the mobile hotspot will let passengers entertain themselves as well as offer a hookup to email, music and traffic data."
Security

What Free Antivirus Do You Install On Windows? 896

Techman83 writes "After years of changing between AVG Free + Avast, it's coming time to find a new free alternative for friends/relatives who run Windows. AVG and Avast have been quite good, but are starting to bloat out in size, and also becoming very misleading. Avast recently auto updated from 4.8 to 5 and now requires you to register (even for the free version) and both are making it harder to actually find the free version. Is this the end of reasonable free antivirus, or is there another product I can entrust to keep the 'my computer's doing weird things' calls to a minimum?"
Earth

The Arctic Is Leaking Methane 303

registerShift and other readers sent in news that the Arctic Ocean seabed is leaking methane. "...climate experts familiar with the new research reported in Friday's issue of the journal Science that even though it does not suggest imminent climate catastrophe, it is important because of methane's role as a greenhouse gas. Although carbon dioxide is far more abundant and persistent in the atmosphere, ton for ton atmospheric methane traps at least 25 times as much heat. ... [One scientist] estimated that annual methane emissions from the East Siberian Arctic Shelf total about seven teragrams. (A teragram is 1.1 million tons.) By some estimates, global methane emissions total about 500 teragrams a year. ...about 40 percent is natural, including the decomposition of organic materials in wetlands and frozen wetlands like permafrost."

Comment SCons (Score 1) 310

Come help work on SCons!

SCons is an Open Source software construction tool—that is, a next-generation build tool. Think of SCons as an improved, cross-platform substitute for the classic Make utility with integrated functionality similar to autoconf/automake and compiler caches such as ccache. In short, SCons is an easier, more reliable and faster way to build software.

It's under active development, and it's the best way to build C, C++, LaTeX, and lots of other types of projects. Build scripts are 100% python so you have the full power of a real language in your build. And... we need new developers to get to the next level! We have lots of ideas for ways to improve it. Come and take a few Easy-tagged tickets and implement them, you'll be amazed how easy it is to contribute. Plus we're friendly.

Communications

Dragging Telephone Numbers Into the Internet Age 239

azoblue writes with this teaser from Ars Technica, presenting a tempting suggestion for online consolidation: "E-mail, IM, Facebook, phones—what if all of these ways to reach you over a network could be condensed into a single, unique number? The ENUM proposal aims to do just that, by giving everyone a single phone number that maps to all of their identifiers. Here's how it works, and why it isn't already widely used."

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