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David Gillies
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All government-run organisations fall prey to producer capture. All organisations that interact with the government become rent-seekers. From a sociological/economic standpoint those rules are set in stone. It's the distilled essence of Public Choice Theory. And David Duff: read what you wrote. 1) there is to be a direct link between doctors and patients with no third party involvement 2) wealthy societies should provide healthcare for impoverished citizens. Which is it to be? The two aims are mutually exclusive. The very existence of healthcare provision for those that cannot afford it compels a third party to be. If someone pays, whether it be an insurance company, government, Lady Bountiful's Fund for Sick Peasants or the mythical and evanescent 'society', then that is a third party by definition. Seems to me that the best solution is to split the difference: those that can pay for their healthcare do, and those that can't are supported via a general societal levy. Of course the prudent among the first group will wish to amortise any future costs via some sort of fund, and those in the latter will need to be subsidised out of the societal fund. So, private insurance and Medicaid, basically. Whoops! Think on, lad.
An anisotropy is simply a deviation from uniformity in a given direction (and an inhomogeneity is likewise a deviation from uniformity in a given region). The deviation is all that is needed to seed the coalescence of proto-galaxies etc.. If a region of space has a locally-enhanced density of matter compared to its surroundings (for that is what an anisotropy or inhomogeneity means in practice), then provided the enhancement extends over a sufficiently large radius, the excess gravity produced by the extra mass will overcome the repulsive effects of the pressure inside the region and will lead to a contraction that will proceed until equilibrium is re-established. From a somewhat technical standpoint, the scale of a local density enhancement sufficient to cause a gravitational collapse into a galaxy or star-forming region is closely related to the speed of sound in the medium. It was only when the universe cooled sufficiently to allow electrons to bind to nuclei (the recombination epoch) that the radius of perturbations capable of undergoing gravitational collapse became small enough to be contained in the observable universe. The radius is known as the Jeans length, after Sir James Jeans who first derived it. This is all beautifully and lucidly explained in Novikov's book. A naive treatment of density anomalies in the proto-universe points to their being much greater than observed, hence driving the explanation of their having been smeared out to a tremendous degree during the brief inflationary era. If you imagine blowing up a balloon from the size of a grapefruit to several billion light years across, you will see that any surface imperfections will become imperceptibly tiny. It's a testament to our engineers and scientists that we can detect the echoes of these tiny imperfections in the cosmic microwave background, a feat which got George Smoot a well-deserved Nobel Prize. From the standpoint of one-off events, we at present have exactly one datum concerning the existence of life in the universe: us. We have no means (at present) of determining whether a universe such as the one we see (with, as you note, a myriad of physical parameters, such as the fine structure constant or Planck's constant, that have to be very close to their measured values for us to exist) is the only one compatible with physics, or whether it was a matter of luck. But our existence is a second-order contingency. It is perfectly possible to conceive of a universe in which life could exist, but does not. Further, the discovery of life outside our solar system would change things utterly. If you find two raffle tickets on the ground, then you are able to make a (weak) determination of the probability of having a winner (technically, the probability space becomes sigma-additive at this point). If we are alone in the universe, then it is impossible a priori to assign a probability to our existence. If we are not, then it is possible. Even if the universe is teeming with life, though, it does not prove any teleological effect. It simply lowers the threshold of likelihood for life emerging given the universe we observe. To summarise: at the present time, we know that if the universe were constituted slightly differently, then our existence would be impossible, but we do not have enough knowledge to determine if such a universe is possible. We know that life can exist, but in the absence of the discovery of life elsewhere in the cosmos, we have no means, even in principle, of deciding how likely it is. It's kind of fun re-visiting these ideas. I've been out of academia for a long time, but studying astrophysics and cosmology definitely equips one with a powerful lens through which to view the world.
Toggle Commented Jul 6, 2009 on Mummy, mummy, my brain hurts! at DUFF & NONSENSE!
Another thing that wine purists get sniffy about is screw tops. If you're not planning on cellaring a bottle of wine, there is absolutely no reason why it needs a cork. I buy a rather nice Errazuriz Chardonnay (Chilean) for about $13 a bottle and it's got a screw top. It's very drinkable.
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