exchemist
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But it is not true that all new theories are mere extensions of older ones. There is no way to reconcile the plum pudding model of the atom with the Rutherford-Bohr one. And it is a stretch, to say the least, to reconcile the Ptolemaic astronomical system with the heliocentric one. Sometimes the previous theory is thrown out completely. Another example would be the phlogiston theory of combustion. Or the cooling earth theory of mountain building. I agree that, quite often, new theories can be seen to be related to earlier ones, as with Newtonian mechanics and relativity or QM, but there is no necessity for this to be so.
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Item 3 looks to me not only unnecessary but actively wrong. There is no reason why a new theory cannot contradict an existing one, so long as it (a) successfully accounts for all the observations that the old one deals with and either ( b ) accounts for something the old one cannot account for, or ( c) accounts for the same observations but in a simpler and more insightful way. An example of (b) would be the Rutherford-Bohr model of the atom contradicting the plum pudding model. An example of ( c) would be the heliocentric astronomical system contradicting the Ptolemaic one. Item 2 seems to be key: it is the ability to account for observations and predict new ones that is the test of validity.
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A Quantum Model having a Mechanism for Wavepacket Reduction (Revised)
exchemist replied to SEKI's topic in Speculations
What I am trying to understand is why you think your "cohesive force" is necessary, that's all. What problem in physics does it purport to solve? It seemed, from your description, to be something to do with preventing dispersion, I had thought. If it is not that, perhaps you could explain to me what the problem is that it addresses. Can you do that? -
A Quantum Model having a Mechanism for Wavepacket Reduction (Revised)
exchemist replied to SEKI's topic in Speculations
I have, and I'm struggling to understand what you are on about. You make what looks like a silly assertion, viz. that a photon cannot but diffuse and thereby ends up "disappearing". That is obviously rubbish, so I am paying you the compliment of not jumping to the conclusion that you don't know what you are talking about. I am trying to see if I can make what you have written align with my own understanding. This is that a wave packet indeed tends to disperse, so that the wave function becomes spread out in space. But that does not mean it eventually "disappears", merely that its position becomes less and less well defined. However, If your response is going to be merely: "Please read", that is rude and unhelpful and I won't waste any more time on your ideas. -
A Quantum Model having a Mechanism for Wavepacket Reduction (Revised)
exchemist replied to SEKI's topic in Speculations
Sorry I mean dispersion. Is this all about wave packet dispersion? https://en.wikipedia.org/wiki/Wave_packet#Dispersive -
A Quantum Model having a Mechanism for Wavepacket Reduction (Revised)
exchemist replied to SEKI's topic in Speculations
I'm wondering if this could be a rather garbled reference to wave packet dissipation. That could be described as a wave form that changes with time, couldn't it? -
Mutation (split from The Selfish Gene Theory)
exchemist replied to Evomumbojumbo's topic in Speculations
So what is your argument now? When you arrived, you were maintaining the whole notion of natural, beneficial genetic change was nonsense, because nature could not "code": garbage in garbage out, etc. But now we have established that argument is hogwash. Nature does do this, in viruses, prokaryotes and eukaryotes. I must presume your argument has now changed to be one of not seeing how major changes in organisms can be brought about by this process. Regarding how easy it is to "test" the degree of change it can bring about, what makes you think this is "easy"? It requires many generations. That is easy to do with bacteria, since new generations occur every few minutes. With a more complex organism a new generation may only occur every few months, or years even. So any "test" will have to be over very long periods of time. Have you worked out how long, for any given organism? What tests are you referring to? Can you provide links? -
Evaporation and condensation as a source of energy
exchemist replied to BestChance's topic in Classical Physics
No. You have 2 tanks at different temperatures. Only one of these can be at the" ambient" temperature of the environment. The other must be at a different temperature, either higher or lower, in order for the engine to work. How is that different temperature created? -
Mutation (split from The Selfish Gene Theory)
exchemist replied to Evomumbojumbo's topic in Speculations
But look at what we've now established. 1) Nature can create new genetic "code" that benefits the organism. So we can forget "garbage in garbage out". 2) The mechanism works by natural selection of variations. This is exactly what Darwin came up with 150 years ago, before the science of genetic sequencing even existed. So we have an independent confirmation that his theory does work, for real, in nature. As to viruses being a special case for some reason, well, no, not really. I only chose SARS-CoV-2 as a topical example that you could not avoid knowing about. There are DNA viruses too, including smallpox, herpes and papilloma viruses. Secondly and more importantly, we also see evolution at work in the same way in bacterial resistance to antibiotics, and in the way cancer cells develop resistance to chemotherapy drugs. So we know this mechanism operates in viruses, prokaryotes (bacteria) and eukaryotes (cancer cells). That is important, since it follows that we can expect it to operate in all organisms - throughout the living world. It only remains to argue (if you insist) about what this mechanism is capable of, i.e. the degree of change it can bring about over time. -
Mutation (split from The Selfish Gene Theory)
exchemist replied to Evomumbojumbo's topic in Speculations
Proteins. @Arthur Smith has explained this in more detail. Also that when we say a code we do not imply there is an intention in it, merely that it is a biochemical template, in the form of sequences of a small number of base pairs, from which proteins are constructed. But to continue my point, now that we agree nature can create new code by variation and natural selection, and that this new code affects the structure and function of the resulting organism, as the virus case shows, you have accepted that this mechanism of evolution has real explanatory and predictive power, i.e. it is a sound scientific theory. Not mumbo jumbo. And clearly "garbage in garbage out"is inapplicable, or it would not work the way that we can see it does. What, then, is your objection to applying it to other cases? -
Mutation (split from The Selfish Gene Theory)
exchemist replied to Evomumbojumbo's topic in Speculations
OK, so that means that nature can create new genetic code, does it not? -
Mutation (split from The Selfish Gene Theory)
exchemist replied to Evomumbojumbo's topic in Speculations
In the light of @Arthur Smith's contribution, it is mutations. So the new variants of SARS-CoV-2 arise via variation by mutation and then natural selection of those variations best able to reproduce. Agreed? -
Mutation (split from The Selfish Gene Theory)
exchemist replied to Evomumbojumbo's topic in Speculations
No, let's deal with my point before you raise a new one. There have been many new variants of this virus. What do you think accounts for them, if not mutations in their genetic material? -
Mutation (split from The Selfish Gene Theory)
exchemist replied to Evomumbojumbo's topic in Speculations
Well that's good. (As you can tell, I am pretty jaded when it comes to internet creationists🙄. But if you are prepared for a serious discussion I'll try not to let it show.) To your point, then, yes natural selection operates on the gene pool in the population. But that gene pool is not static, because of mutations. The current waves of variants of the SARS-CoV-2 virus are a testament to that. -
frequency of EM wave in classical and quantum physics
exchemist replied to donniedarko's topic in Quantum Theory
The two cases are not quite as different as you may think. In QM the emission of a photon is driven by something called a "transition dipole moment": https://en.wikipedia.org/wiki/Transition_dipole_moment. You can think of this as somewhat analogous to the oscillating dipole created by an oscillating electric charge. A transition dipole moment can arise due to an electron moving between orbitals in an atom or molecule, or it can be something more obviously "physical", like the change in vibration state of a molecule with a dipole moment (molecules with no dipole moment do not emit or absorb in the infra red) or a change in the rotational state of a molecule (again, molecules with no dipole moment do not emit or absorb microwaves). So you still need some kind of oscillating or rotating dipole moment in order to emit or absorb EM radiation, even when modelling it by QM. The fact that the frequency of the radiation is determined by the energy difference between the two states is however not something the classical picture can account for. This goes right back to what Einstein got his Nobel prize for (the photo-electric effect and Planck's E=hν). -
I presume you mean rate of precipitation. Rates of reaction in solution depend on various factors in addition to the reactants involved, notably concentration and temperature. So I don't think it is possible to answer your question. But @John Cuthber may be able to provide some examples of reactions in which a product precipitates rapidly. My inorganic chemistry is too rusty for me to able to do that without looking things up. Though, as I recall, BaSO4 precipitates quickly from mixing suitable solutions e.g. BaCL2 and Na2SO4.
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Mutation (split from The Selfish Gene Theory)
exchemist replied to Evomumbojumbo's topic in Speculations
Not sure. He seems to have fizzled out. He does seem to have a special knack of quarrelling with just about everyone, eventually. But now that Philip E Johnson, the lawyer who founded the ID movement in the USA, has died, I think all those guys will soon be looking for other things to do. -
Mutation (split from The Selfish Gene Theory)
exchemist replied to Evomumbojumbo's topic in Speculations
Haha, yes could be. But I suspect it may be one of these creationist "seagulls" that I've encountered before. At one time William Dembski ran a course, at some Baptist university in the Southern USA, in which he awarded points to students on one module of the course for signing up to science sites and attacking evolution. Normally there would be a flurry of posts for 24-48hrs - and then radio silence. The posts varied in inanity. But the idea of it not being possible for order to emerge spontaneously cropped up quit a bit. Dembski is history now (he got sacked), but maybe someone else is doing something similar. -
Mutation (split from The Selfish Gene Theory)
exchemist replied to Evomumbojumbo's topic in Speculations
Not if you understand the principle of natural selection. But from your short posting history here (not to mention your choice of user name), my guess is you will sidestep what natural selection says and come up with non-analogies like "tornadoes in junkyards". If you continue to post at all, that is. I will content myself with pointing out that the order in an open system can increase by purely natural processes, so long as entropy (or disorder) is increased elsewhere. This happens all the time in nature. So "garbage in garbage out" is not applicable. -
I found this on Wiki: Another size and format was that of radio transcription discs beginning in the 1940s. These records were usually vinyl, 33 rpm, and 16 inches in diameter. No home record player could accommodate such large records, and they were used mainly by radio stations. They were on average 15 minutes per side and contained several songs or radio program material. These records became less common in the United States when tape recorders began being used for radio transcriptions around 1949. In the UK, analog discs continued to be the preferred medium for the licence of BBC transcriptions to overseas broadcasters until the use of CDs became a practical alternative. From: https://en.wikipedia.org/wiki/Phonograph_record#78_rpm_disc_sizes
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You've already done this, haven't you, 8 years ago? What do you hope to gain by repeating it?
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I think that will be because of where volcanism occurs. Volcanism arises in three types of location: - spreading centres, such as mid-ocean ridges, - subduction zones, such as island arcs - mid-plate hot spots Whereas for hydrocarbon deposits one needs a sedimentary location that has not been subject to subduction or intense heating for several tens of millions of years. Subduction zones and spreading centre, where crust is turning over or being newly formed, thus seem very unlikely to be places where hydrocarbons can accumulate. In principle one could get a new hot spot, from time to time, in the middle of a plate carrying continental crust, which might contain hydrocarbons. But the chance of that is pretty small, I'd have thought. Other way round surely? Magma originates in zone of partial melting in the upper mantle or lower crust, whereas hydrocarbons form from living organisms on the surface that have become buried, in sedimentary formations.
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If you were to confine yourself to discussing the historical evidence, as I am trying to do, there would be no problem. Personal opinions on Christianity as a whole, however, have no bearing on historical evidence. That distinction does not seem confusing to me.
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The historian, however, will consider the evidence of the sources. As in science, proof is not to be expected, but evidence that is consistent can suggest what may have occurred. So far as I am aware, there is no evidence that Saul of Tarsus was an invention, whereas there seems to be evidence from more than one source for his historical existence. Enough to persuade non-Christian (ex-Christian) historians like MacCulloch, at any rate. In a thread about Jesus, this about St. Paul is a bit of a side-issue, admittedly, but perhaps for him too, one needs to distinguish evidence from personal prejudices. Where Jesus is concerned, MacCulloch seems to think the main evidence for Jesus as a historical person comes from his preaching style as reported in the gospels, which he seems to find highly idiosyncratic: the use of parables, the repeated use of the enigmatic phrase "Son of Man" and so on. He feels like a real person. But MacCulloch seems more non-committal about Jesus than about Paul, whom he confidently describes as a businessman (in fact a tent-maker) from Tarsus.
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Agreed. A fascinating book. I'd also nominate Martin Brasier's "Darwin's Lost World". This is a readable, first hand account of palaeontological research into the development of preCambrian life, i.e. the mysterious stage before things had hard parts that fossilise well. It introduced me to the enigmatic Ediacaran fauna and insights such as as the impact on life of the coming of the mouth.