Everything posted by sethoflagos
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Airlines And Other Private Companies Going Into The Space Industry
Have you considered investing in this bold new venture?
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Humans' and baboons' common ancestor
Dawkins has used hypothetical cases such as this as a reductio ad absurdum criticism of the Linnaean classification system. In particular, that intermediate evolutionary forms must be shoehorned into either a parent or daughter species at some arbitrary single point mutation event. The reality is of course, that genetic isolation etc allow the transition to occur over many generations of intermediates. The OP is simply an attention seeking gross misrepresentation of Dawkins' argument.
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Funding Dinosaur Research
I responded to your question about the funding of palaeontological studies in good faith only to discover that your OP was more of a vehicle to peddle conservative fiscal propaganda. Or at least take its dogmatic assumptions at face value. Okay then: In general, private commercial enterprise requires a supply of well-educated young recruits (including palaeontologists and rocket scientists) but is too short-sighted and avaricious to fund public education themselves. Relying on the population to fund their own individual education creates fundamentally unstable, self-perpetuating tiered societies where the majority are denied access to good education and the better-paid jobs that follow on from that due to lack of means. Most of the more successful economies fund universal education programmes through progressive taxation policies leveraging preferentially on commercial profits and the wealthier sections of society to maximise the opportunities for all to realise their full potential. This latter option carries the additional benefit that a better-educated majority is more likely to appreciate the fairness and political stability of such a system, and less likely to indulge in armed insurrection for example. Of course, there are those who prefer the privileges they gain from less fair systems of wealth distribution. Funding for palaeontological studies for example is under constant pressure from religious fundamentalists for example as its findings tend to belie their underlying mythologies.
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Funding Dinosaur Research
A good dinosaur fossil can be a very valuable commercial property. Plus palaeostratigraphy (the dating of rock samples by eg their fossil assemblage) is big business in mineral extraction etc. Maybe it's graptolites and conodonts rather than dinosaurs in that case, but the economy still needs a good reserve of trained paleontologists to identify them.
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Residual Energy after Photon Adsorption
That's actually quite mindblowing. Thanks!
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Residual Energy after Photon Adsorption
You really have to look at these interactions holistically don't you. The photon momentum is relatively tiny, but it still must result in a small but quantifiable shift in the kinetic energy of the absorbing molecule which may be +ve or -ve depending on frame of reference. This in turn also impacts the relative values of initial photon energy and electron orbital shift energy. If this effect can be accounted for in doppler broadening, then at least my degrees of freedom issue may go away. I don't think you can use the word 'generally' when your justification is based on the specific case of a boolean relationship. Applying this reasoning to a continuous variable like photon frequency seems too big a jump for me.
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Residual Energy after Photon Adsorption
Good point, however that doesn't appear to challenge the 1st Law in and of itself. Simple absorption is a little different. Okay, an atom can absorb an incoming photon of say 1MHz above or below its standard excitation frequency, but it I can't see it 'remembering' that it has done so. When the excited electron drops down to ground state, I'm assuming that it too could be say +/- 1MHz away from standard with the same probability as the absorption case and for the same reason - Heisenberg. But this leaves us with small accounting errors in both the energy and momentum budgets which even if they average out to zero in the long run introduce the same sort of fuzziness as raised in my 'How Sacrosanct is Conservation of Momentum in QM' thread. I wondered if the discrepancies could be dissipated thermally, but that runs into a degrees of freedom issue. One discrepancy can only balance one conserved quantity I think.
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Residual Energy after Photon Adsorption
Of course. Blasted autocorrect. Aha! So it's bounded by the uncertainty principle. That makes sense. Thank you!
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Residual Energy after Photon Adsorption
QM calculations these days are so precise, at least for the simpler species, that electron orbital transition energy levels can be calculated with great precision. This in turn defines the (minimum?) frequency of the energising photon with similar precision. The probability of receiving an energising photon of exactly the required minimum energy seems to me to approximate to zero, and yet the excitation definitely happens. What happens to the mismatch between orbital energy change and photon energy?
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Biology of genius
And not just any old doctor - a paediatrician no less: a professional specialising in child development.
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How Sacrosanct is Conservation of Momentum in QM?
Those addressed subsequently by @MigL.
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How Sacrosanct is Conservation of Momentum in QM?
Am I right in reading 'off shelf' as 'off shell' ie not a solution of the mass/energy equivalence eqn?
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Biology of genius
Reasoning in the absence of supporting evidence is just wishful thinking.
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How Sacrosanct is Conservation of Momentum in QM?
Not explicitly.
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How Sacrosanct is Conservation of Momentum in QM?
Exactly. Can we now develop @exchemist's point and address whether the random quantum fluctuations of the vacuum state can perturb the momentum of a gas molecule?
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Has anyone tried this at home?
I guess I can take a couple of negs here and there, but it would be nice to know the reason.
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How Sacrosanct is Conservation of Momentum in QM?
That's actually quite a big deal.
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Has anyone tried this at home?
And thus the language of our noble ancestors lies dying in the no man's land of post-modernist chutzpah
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How Sacrosanct is Conservation of Momentum in QM?
Presumably this is consistent with a classical picture of momentum exchange in the interaction of a gas molecule and a photon. How about interaction with a random quantum fluctuation? Can the gas molecule 'leak' momentum into displacement of such 'virtual' particles? I'm really asking about phenomena distinct from the measurement problem. I can buy some fundamental uncertainty in the actual path taken. More, I'm trying to narrow it down from some kind of random walk to a spectrum of possible paths all of which are straight lines.
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How Sacrosanct is Conservation of Momentum in QM?
I've seen statements such as this kicking around for decades and always been troubled by a niggling doubt. I imagine that the phenomenon can be explained by normal electron scattering and tunnelling without invoking any deviation to conservation of momentum. But is that all there is to it? Is the momentum vector of a particle subject to variability due to, say, random quantum fluctuation in local field strength? This idea seems somewhat belied by the near point image my eyes can make of a distant star, but even so... My primary contextual interest is in the absolute deterministic nature of gas molecule trajectories between collisions - ie how 'straight' are their paths through free space.
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Has anyone tried this at home?
Not here. Within the circles I move in, beer is the social brew of choice. Only to geordies who ask daft questions. More the chutzpah of those who believe their taste in tea is somehow superior to anybody else's. There is no universal 'perfect cuppa'. Just an individual's preference. The similarity of sugar cellars to salt cellars in many establishments has caused most of us to have conducted unplanned experiments with salty tea.
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Has anyone tried this at home?
It does. Been recycling tepid tea that way for years.
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Has anyone tried this at home?
It'd need a minute in the microwave otherwise you may as well be drinking bathwater.
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Has anyone tried this at home?
Bless their little cotton socks! What do they miss out? The preheating the teapot bit, or the tea cosy to keep the heat in?
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Has anyone tried this at home?
There's likely as much arsenic in the water you stew it in. See https://pubmed.ncbi.nlm.nih.gov/25526572/