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exchemist

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Everything posted by exchemist

  1. Do you mean this sort of thing?: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6174548/
  2. I think the IR spectrum of CO2 is well characterised, isn’t it? So from that one can presumably model things from what radiation a given concentration of CO2 over a given path length would be expected to absorb. Or are you after how the model was constructed?
  3. My understanding is they envisage a stream of fuel pellets, each "ignited" in turn by a laser. As in our previous discussion about tokamaks, there's some way to go before the energy output exceeds the input enough to run the laser. Also I don't know how they extract the energy. I presume it would be by some kind of intercepting shield that gets hot and raises steam.
  4. "Without intellectual honesty", my arse. Several of us have tried really hard to understand what you are trying to do. You, on the other hand, have been almost entirely unhelpful in your responses.
  5. Several people have done so. You claim current theory says a photon spreads and out and "disappears". But current theory does not say it disappears. So your "cohesive force" seems to address a non-existent problem. But in case I have misunderstood, I've asked you about this, and you have failed to respond. The dispersion of wave packets is not a problem, so far as I am aware, but in any case you have denied that dispersion of wave packets is what you have in mind. So if it is not that, I ask again: what problem in physics are you addressing with this idea? If it addresses no problem, it can be dismissed as a scientific hypothesis, by Ockham's Razor.
  6. ....and, ahem, not relevant either, for the reasons just expounded by @String Junky 😉 A good historian should be able to review evidence dispassionately, whatever his personal sympathies. Your point about the rules for capital punishment is presumably why the gospel story includes that interrogation of Jesus by Pilate as to whether or not he considers himself a king and why Pilate (in the story) fudges it by inscribing "The King of the Jews" on the cross, to make the execution look legitimate, even though he doesn't believe it.
  7. What are your ideas so far, then?
  8. I have read it and tried to engage you to find out why you say what you are saying. Let me repeat my earlier question to you:- 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?
  9. Agreed, except that I would say an "observation" rather than an "experiment", as it is more general: doing "experiments" in astrophysics is not easy. However I think it is instructive to keep in mind that, even in physics, one can only apply mathematics once one has developed conceptions of the quantities to be included in the modelling: energy, momentum, electric charge, velocity, or what have you . To do that, words are required.
  10. 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.
  11. 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.
  12. 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?
  13. 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.
  14. Sorry I mean dispersion. Is this all about wave packet dispersion? https://en.wikipedia.org/wiki/Wave_packet#Dispersive
  15. 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?
  16. 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?
  17. 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?
  18. 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.
  19. 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?
  20. OK, so that means that nature can create new genetic code, does it not?
  21. 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?
  22. 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?
  23. 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.
  24. 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).
  25. 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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