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Comment Re:Say what? (Score 1) 199

The basic equations for fluid dynamics are the Navier-Stokes equation.

So, I fully grok your argument, but I am wondering about one thing.

Is the Navier-Stokes equation REALLY the basic equation for fluid dynamics? .

No, of course not, there is a lower level of particle interactions. You can't really usefully compute them either.

Comment Re:So. Let us imagine. (Score 1) 392

I am a man. I am a volunteer to go on such a mission, as part of the first generation. I will necessarily have to breed, in order to do my part for overall mission success. Does this mean I may have to fuck a woman I find ugly, dumb, boring, vulgar or otherwise unattractive ?

General "Buck" Turgidson: Doctor, you mentioned the ratio of ten women to each man. Now, wouldn't that necessitate the abandonment of the so-called monogamous sexual relationship, I mean, as far as men were concerned?

Dr. Strangelove: Regrettably, yes. But it is, you know, a sacrifice required for the future of the human race. I hasten to add that since each man will be required to do prodigious... service along these lines, the women will have to be selected for their sexual characteristics which will have to be of a highly stimulating nature.

Comment Re:NP vs. P doesn't exist in the real Universe (Score 2) 199

Well, if the universe can do it then a simulation must exists that can do it, it's just a question of efficiency.

Not true for chaotic systems, which are incredibly common in nature. The coffee and cream in your cup can be simulated, but not computed, and the situation is much, much, worse for (say) a Hurricane, or the Great Red Spot, or a Galaxy.

I do agree with you about the limitations of predictive models...

Comment Say what? (Score 5, Insightful) 199

I have not had time to read the article, but the summary is either incoherent or wrong.

Here is an analog to illustrate why :

The basic equations for fluid dynamics are the Navier-Stokes equation. But the new idea is that this requires an additional assumption — that an efficient algorithm exists to solve the equation for complex macroscopic systems. But is this true?

In the case of the Navier-Stokes equation, almost certainly not. In fact, it is generally not even clear if solutions even exist, or if they are non-singular.

If this is right, then complex fluid motions cannot exist, which explains why we do not (and cannot) observe them in the real world. Voila!"

So, I guess we can cancel this years hurricane season.

In other words, there are many things in nature that are computationally hard, and yet happen any way. Using computational hardness as a reason why a physical theory cannot be right does not, to put it mildly, agree with past experience.

Comment There is a downside (Score 1) 144

This might work fine, but if it didn't work you would probably get arrested, get put on a blacklist and, if it was really your day, get close attention from the likes of the French DGI. There is nothing like a week of interrogation to spice up your vacation.

Comment Re:No expectation of privacy (Score 3, Insightful) 405

Sorry, but this is BS. I have such an expectation of privacy. That you would deny it to me means that this is a political, not a legal, matter, and merely stating that an officer does not need a warrant does not cut it in political discourse. I would also note that there is nothing, not one syllable, in the 4th Amendment about expectations of privacy in limiting the search of your "effects" (i.e., your personal property, such as, e.g., your car). All of this is a later invention by the courts; being invented, it can be changed as conditions change, and they have indeed changed.

In the internet jargon, surveillance in a free society does not scale. It is one thing if a policeman walks down my street and happens to smell or see something. It is quite another if, say, I woke up to find that there are 20 policemen stationed just outside my curtilage, each trying to peer in my windows with binoculars, and they stayed in position all day, every day. To be blunt, one is reasonable, the other, tyranny. SImilarly, if every time I drove away from my house I was followed by a convoy of police cars tracking my every move, I would conclude that I was the victim of official harassment (or worse), and react accordingly (say, by going to a Judge and / or the newspapers with my complaints).

Now that is possible to obtain this level of surveillance without actually delegating 20 policemen to peer through my windows, or to follow me about, and without it being obvious to the victim, the legal system will simply have to expand the legal expectations of privacy, or we will find ourselves living in a Stasi-like tyranny.

Comment The shades of Chief Gates (Score 2) 405

This is a police force where the Chief of Police in the 1990's, Daryl F. Gates, said that casual drug users "ought to be taken out and shot," which prescription being specifically aimed at those "who blast some pot on a casual basis."

Mr. Gates is no long with us, but not because of any repudiation by the LAPD.

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