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Comment Re:What countries? (Score 1) 159

Not "to enter", to immigrate.

I had to be fingerprinted (all 10 fingers) twice during my immigration process (once for the green card, and then again for naturalization application).

If you are lucky enough to have been born in U.S. (or born to U.S. parents), you don't have to get your fingerprint stored into a database, of course ...

Comment Re:Not even a fine? (Score 2) 92

Take British telecom (mentioned earlier in this thread) for example: A revenue of about 30 billion euro / year. A minor mistake should lead to 0.25% of 30 billion = 75 million euro.
And that's for small mistakes.

Revenue is the wrong number to use. Use the percentage of earnings (or, if not actual reported earnings, at a minimum, revenues minus expenses directly related to generating those revenues), which is more comparable to a person's salary. You should arrive at a figure in the millions or hundreds of thousands, and guess what—that *is* what corporations get fined rather routinely when they do something bad that they do get caught (this isn't to say they always get caught when they do something bad, but for that, I go back to my original point).

Comment Re:Not even a fine? (Score 1) 92

Companies are legal entities that can get away with far too much!

Really? Do you get caught and punished every time you do something bad? I've frankly sped (at 10, 20+ mph above posted limits) many times and done things that I'd be too embarrassed to admit on Slashdot. I've not been caught or punished for any of these transgressions. Yet.

All persons (both real and legal) get away with a lot of things they do; after scaling for size and influence of each person, I don't think there's a preferential treatment for either corporations or real persons.

If there's one entity that gets away with far too much, it's the government. Take their accounting rules for example; if any private corporation accountant used the same rules as the government (in counting liabilities, especially), that would land him in jail.

Comment Re:How does this happen? (Score 1) 295

Which is why GPL shouldn't be used for art; GPL is written with programs in mind. If you want more general application to all copyrightable works, Creative Commons does a better job.

By the way, in general, artwork and program are covered by different copyright, even when the artwork is distributed as part of some program (see: the spat between the Debian team and Firefox).

Comment Re:Interesting. (Score 2) 155

Yes, I can, because "constructing a 3D model" is what may or may not be done after processing the "full light field", which THEY define as all the rays passing through an object.

You might want to look up "light field"; apparently it's a well-defined term within the field (which has some connections to what I'm familiar with and hence was talking about but is formulated differently for different application). In particular, "full light field" is different from "all the light rays".

Measuring the full light field means measuring all the available information (in a different context you may be familiar with, if you work with light in any way, an analog would be a full Stokes polarimeter that measures all available polarization parameters of the light, not just one or two, as most cameras and filters do) in the light that the sensor receives, whereas measuring all the light rays would mean what you were talking about---capturing the light emitted into all solid angles.

I'll admit first that I myself wasn't familiar with the term "light field" and the term itself did sound a little sci-fi-y, but it is a valid, technical jargon, not just marketing speak or jibberish you see in sci-fi.

Comment Re:Interesting. (Score 1) 155

Um, if they were really claiming to capture "all the light rays", in addition to measuring information from the light ray that effectively allows you to calculate the distance to the object, then they would be claiming to build a 3D model from all visible information. You can't simultaneously not believe that they are claiming to construct a full 3D model and also believe that they are claiming to capture "all the light rays": you have to either think they are making both claims (which amounts to a single claim) or neither, at least logically speaking.

And "discarded" and "never measured" is the same thing, too. The measurement process destroys the photon (or, if you are classically inclined, the light ray); whatever information you neglected to measure from the photon is discarded.

Comment Re:Interesting. (Score 1) 155

And if you know anything about a camera lens, neither can this "light field camera". Any light ray that doesn't travel towards the camera lens cannot be recorded by that lens. Any lens. Of "all the light rays in a scene", very few travel exactly the correct direction. (You can calculate what percentage by choosing a point in the image and determining what percentage of the whole sphere the solid angle of your lens intercepts.)

I don't think they are claiming to build a full 3D model of the subject (that would indeed be sci-fi). I do think they are claiming to use additional information usually discarded by conventional light sensors (i.e. CCD), i.e. something that corresponds to the radius of curvature (I'm more familiar with the concept in the laser-beam setup, so I don't know exactly how that translates when you consider a diffuse light source that most objects present, but the paper abstract talks about light rays, like the rays in geometric optics).

I can see how that additional information can be used to re-focus, since with that additional information you can completely characterize the light source and know how far it is; the 3D thing (in the video, you can see some features that either hide behind the railing or come out), I'm not so sure.

Comment Selection bias, anyone? (Score 1) 136

We can't know for sure since they aren't divulging their source, but some of the services listed are too sophisticated (esp. Gmail, even if you don't believe in competency of those who run Hotmail) even to store passwords in cleartext anywhere.

If I had to guess at how they obtained these passwords, they did it by actual hacking of the accounts (or somehow got a hold of the password hashes to run faster attacks on), and in that case, the accounts with weak passwords are the low-hanging fruits; of course the list will contain many, many weak passwords subject to various dictionary attacks.

This doesn't explain everything, since looking through the password list, I do see a few that actually look randomly-generated, such as "Zt8bNOI655" (maybe they used keylogger trojans in addition to other methods), but unless use of dictionary attack of any form can be ruled out, statistically, this list is worse than worthless—it's downright misleading, unless the only claim made is that there still exist users who use weak passwords.

Comment Re:There was already an experiment that could do i (Score 1) 112

Hm. I'm not sure how that works, exactly. If two photons were entangled, measurement on one constitutes measurement on the other (this is the basis of EPR paradox, the seemingly superluminal signal-sending).

If the claim is that a measurement is made on one without disturbing the state of the other entangled photon (i.e. measuring its position, or, in the experiment you described, its polarization is supposed to collapse the polarization state of the entangled photon to that determined by condition of entanglement), then it's a different kind of measurement than what I learned.

Comment Experiment is about "Measurement" not UP (Score 4, Interesting) 112

Averaging over many measurements won't allow you to "defeat" uncertainty principle, as uncertainty principle tells you the width of the distribution (of measurements). If you wanted to get a precise measurement of the center of that distribution, yes, you can take many averages and reduce the error on that (see error of the mean), but the width of the distribution (given by uncertainty principle), remains unchanged.

Reading the paper abstract:

A consequence of the quantum mechanical uncertainty principle is that one may not discuss the path or “trajectory” that a quantum particle takes, because any measurement of position irrevocably disturbs the momentum, and vice versa. Using weak measurements, however, it is possible to operationally define a set of trajectories for an ensemble of quantum particles. We sent single photons emitted by a quantum dot through a double-slit interferometer and reconstructed these trajectories by performing a weak measurement of the photon momentum, postselected according to the result of a strong measurement of photon position in a series of planes. The results provide an observationally grounded description of the propagation of subensembles of quantum particles in a two-slit interferometer.

It looks like the goal of experiment is to nail down (or get further in nailing down) what constitutes "measurement". But I'm still trying to figure out how this experiment is different from the standard QND (which doesn't claim not to collapse the wavefunction as all measurements ought to).

Comment Re:Thanks for inappropriate ratings (Score 2) 180

Thanks for making the ratings less useful.

It depends on what you are trying to get out of the ratings. If the rating is meant to reflect the entire purchasing experience, it's entirely appropriate that the overall rating should include how pleasant it was to buy from a particular vendor.

Yes, if you want to use the rating to gauge to product and buy it elsewhere, rather than the site where you found the ratings, including the vendor performance would make the rating less reliable for you, but it's you who are using the rating in an unapproved manner, not the customers who are rating inappropriately.

This isn't to say that ratings break-down by category won't help, though.

Comment Re:Not so bad to have different systems. (Score 0) 2288

Well, now, tell me how long is a meter.

The problem with the metric system is there is nothing convenient that easily serves as an everyday reference.

On the other hand, for most adults, the length of their forearm easily serves as a reference to feet within 10 to 20% precision (of course, they can use their feet, too, if they wanted).

The only easy everyday reference to a meter I can think of is a gait—most people's two steps is about a meter—but that's far less concrete than length of body parts.

For precise, scientific measurements, by all means use the metric system; everyone already does (even in U.S.!). For everyday measurements and estimates, imperial system is superior to metric system.

Comment Re:I know he has a lot to be upset about (Score 1) 233

Same way it read to me. I'm imagining Bilbo climbing out of the well with a shotgun. "This! is my boomstick!"
A hobbit with a 'tude? You know that's unheard of.

This makes sense only if you ignore the italicization of The Hobbit.

In usual convention, italicization indicates a movie or book title (among others), so if you read it as the book The Hobbit started shooting ... you have an overactive imagination.

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