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Comment Re:Resources spent delaying the inevitable are was (Score 1) 363

By the way, I am old enough to remember scientists in the 1970's forecasting a coming ice age based on what they thought to be incontrovertible science.

No, what you are old enough to remember is a media scare based on amplifying the predictions of a few scientific papers, and one that didn't even make sense given that most of the scientific papers coming out at that time predicted warming . The moral of this story is not that climate science is untrustworthy but that that you should not rely on the media for news about science.

Comment Re:Bipartisan support (Score 1) 548

I do not want to pay income tax, therefore, it is involuntary.

Sure, but that's irrelevant to my point that it is an abuse of the term "rob" to say that someone is asking to be "robbed" merely because they are asking to pay more in taxes in exchange for (theoretically) better government services.

Comment Re:Bipartisan support (Score 1) 548

I can't believe the amount of sheep who scream "rob me rob me yes please rob me some more!" in the name of raising taxes however whenever a tax hike is proposed, though. I guess I'm too old and too cynical now.

Given that the word "rob" implies that something is being taken involuntarily, referring to people voluntarily calling for themselves to pay more in taxes as asking themselves to be "robbed" doesn't imply that you are old and cynical so much as senile.

Comment Re:Sound strategy (Score 1) 735

There's also a problem with Palestine entering the ICC (it can, because it will be a full-fledged state in the near-term). Then, the ICC would have jurisdiction to judge people in Israel and the US. And it doesn't bode well for America to openly support a country that will be accused soon enough of a few nasty crimes.

The ICC has no jurisdiction to judge people in Israel and the U.S. because they are not parties to the treaty founding it.

Comment Re:Winning at all costs? (Score 2) 374

Indeed, that single quote in the context of the situation has told me enough about Skype to prevent me from even thinking about ever working there in the future.

Making it clear that you will screw over employees who will not stay with you indefinitely since you are out to "win" is not only a horrible attitude towards life, it isn't even a good way to attract "the best and the brightest people to build great products" because most such people get bored working on the same products for a few years and will want to move on to new challenges, so if you make it clear that anyone who decides to move on will be screwed over then you are basically saying, "If you are the best and brightest then don't work here because we don't want the likes of you!"

Comment Re:President Obama (Score 1) 247

Just because Mr. Obama has become the President doesn't mean that he has stopped being an ordinary man, so it is not disrespectful in the slightest to call him by the same respectful title that one would use for any other ordinary man.

It's not like Mr. Obama has ascended to the realm of the gods (unlike a Gnomish Healer I once played, but that is a different story...); he is just another human being like the rest of us who unlike most of us happens to hold a particularly important position.

Comment Even if he *didn't* sign the bill it would be law. (Score 1) 247

In the end it really doesn't matter whether the autopen counts as a signature or not because the Constitution has the following to say:

"If any Bill shall not be returned by the President within ten Days (Sundays excepted) after it shall have been presented to him, the Same shall be a Law, in like Manner as if he had signed it, unless the Congress by their Adjournment prevent its Return, in which Case it shall not be a Law."

So even if the autopen didn't count as a formal signature, when ten days had passed and the bill was not returned to Congress with his objections it would have become law by default anyway, so in the worst case that would mean that the Patriot act was out of effect for ten days and then immediately resumed.

Comment Re:Questions answered in this thread... (Score 1) 173

Myself or others will try to answer questions

You misspelled "I". That's pretty good. I'd never before seen a one-letter word misspelled.

Presumably he figured that his time would be better spent battling the evil forces of spam then carefully proofreading his Slashdot comments, but I suppose that not all of us share the same priorities.

Comment Re:Many-worlds is the most practical interpretatio (Score 1) 387

That is completely wrong...This is not philosophy, this is mathematics.

That is not an argument. Why is it completely wrong? And why is Richard Feynman incorrect for espousing it? And why is it so obvious from perception?

Sure, I will grant you that if you cut my explanation from a quote then it does sound like I did not make an argument.

The point is that although it is true that we need to interact with the system in order to measure it, it is not obvious that this should specifically cause the wave function to collapse. Thus, the explanation you gave is not sufficient to understand why the wave function collapses. By contrast, the No-Cloning theorem does provide a sufficient explanation.

Feynman was most likely giving an approximation of what was going on for the ears of non-physicists and so one should be wary about reading into it too literally.

Finally, I have never claimed that the No-Cloning theorem was the obvious explanation for wave function collapse; in truth, there is little that is immediately obvious about quantum mechanics.

The reason why measurement affects reality is because of the No-Cloning Theorem which dictates that quantum information cannot be copied, so the most that you can do is entangle yourself with the particle which creates the perception of a collapsing wave function.

This is as backwards as saying that "the amount of impedence of the individual components of an AC circuit is caused by the imaginary exponential." No, the imaginary exponential was devised to easily calculate the impedence. To pretend that the math makes reality is to put the cart before the horse. Quantum mechanics and the no-cloning theorem are concepts used for predicting reality. They are concepts of method. They do not create reality.

Sure, but the model you outlined with particles bouncing is also just a model of reality rather than being reality itself, so you can't claim that the problem with my explanation is that unlike you I invoke a model to explain what is happening.

Comment Re:Many-worlds is the most practical interpretatio (Score 1) 387

I thought decoherence was the proposed resolution to the measurement->collapsing wave function approach of interpreting QM. Has this been derailed?

No, actually in retrospect I see now that quantum decoherance exactly corresponds to the model that I described, its just that it had never been explained clearly to me so I thought it was referring to something else. (Ironically the wikipedia article I just looked at now was in many ways clearer than the explanation I'd received in my classes, though in fairness it might just be that I have a few more years of experience under my belt so that it makes more sense to me now!)

Anyway, so in short you are absolutely right, and I appreciate you asking this question because it caused me to learn something. :-)

Alternatively, I've seen a proposal that QM is just a probability algorithm correlating various observables, as in

Hmm, interesting, I am not familiar with that result, but it might answer a question that is left-open by the many-world interpretation: why is it that the square of the amplitude of a component in the wave function corresponds to the probability of measuring it in that state?

Comment Re:Many-worlds is the most practical interpretatio (Score 1) 387

Nonetheless, the fact remains that *I* as a subjective human being can do experiments to determine whether I am the only one who can collapse wave functions or whether other human beings do so as well. That is, this distinction does not require the assumption that a objective reality exists, only that I be able to distinguish between two different kinds of patterns that I perceive.

Furthermore, while it is technically true that there is no reason not to believe that I am a privileged being in this universe and so the rules apply different to me than to other entities, models where I do not make this assumption have historically tended to be better descriptions of my perceptions than those where I do make this assumption.

Comment Re:Many-worlds is the most practical interpretatio (Score 1) 387

Every such experiment we have performed has shown that the wave function does in fact *not* collapse inside the box but rather splits.

You could also argue from this that the wave function of the apparatus inside the box is entangled with the particle it's measuring, and doesn't collapse until we open the box. That's what Schrodinger's thought experiment with the cat was about, right?

The key is that you can do experiments that tell you whether the state inside the box has collapsed or not without measuring the state itself, which is different from Schroedinger's thought experiment in which you do measure the state inside the box.

In fact, a variant of this principle is used in something called quantum error correction (which is one of the subfields in which I do research), where you can measure and correct error in an encoded quantum bit without ever measuring the bit itself.

Comment Re:Many-worlds is the most practical interpretatio (Score 1) 387

Although Physicists like the Many Worlds interpretation, philosophers hate it. They all much prefer the Bohm interpretation, usually called a statistical interpretation of QM. Da Cog correctly describes this as a deterministic interpretation. The wave function represents what we know of the state of the QM system. Naturally it collapses if we know something new. Naturally, in a closed unmeasured system, it doesn't collapse. For philosophers this is a compelling interpretation. However, for physicists it is not compelling because it complicates the maths. So the choice, unless an experiment can be done to decide between them, is between an interpretation that is ontologically extravagant but mathematically elegant on the one hand, and an interpretation that is ontologically elegant but mathematically complex on the other.

That is a very good summary of the situation. Personally as a physicist I don't see the assumption of many worlds as being ontologically extravagant --- especially since there aren't really many worlds, there is just one quantum world that contains what *we* as classical creatures would consider to be multiple parallel realities --- but it does drive philosophers crazy. :-)

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