This is true of any parent who has ever emigrated anywhere (i.e., basically everyone's ancestors).

SInce the same is also true of any parent who didn't emigrate but stayed put (everyone else's ancestors), I myself don't see this as a real moral Dilemma

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.

Yes, it does. The presence or absence of a vacuum has nothing to do with inertia.

I think terraforming is different, or at least terraforming of something close by. If we terraform Venus (say) and it needs more nematodes, well, Earth is not far away. If you are 30 light years away and your ecosystem crashes, you better have a plan B that doesn't involve getting stuff from Earth.

To me, the question is not really how many people, but how many earthworms, and in general plants, bugs, birds, animals, etc.? At present, we really have no idea what is needed, nor in how much variation within each species, but I suspect the real answer will always be "more that we think."

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...

And that is basically my response to the AI proponents who say "a computer can calculate anything a brain can think."

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.

The Third Rule that you do not talk about the Second Rule.

Wrong.

The first rule of FLIGHT CLUB is...

You do not talk about how you got your tickets

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.

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.

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.

Actually, scratch the above. Reading their paper and the Dyson paper, the frequency limit is set by the seismometers, not by the normal modes of the Earth.

The crucial thing is that they improved the limits in the narrow frequency band where the Earth is a resonant detector :

in the frequency range 0.05 Hz – 1 Hz

This is very cool, but note that it is at a frequency where there are not a lot of expected sources (stellar-mass binary black hole coalescence is up in the kHz range).

The announcement on Monday about inflationary gravitational waves is likely to get a good deal more scientific attention.