exchemist

No, it’s catenation chauvinism, if it’s anything. If you can’t make long chain molecules, you have to be looking at such a radically different biochemistry that really you would be just guessing as to whether it might work or not.

The problem, though, is it has only 3 valence electrons but needs to share 8 ( i.e. form 4 bonds) to form a closed n=2 shell through covalent bonding. Hence it has a tendency for multicentre bonding, which tends not to lead to chains, i.e. catenation does not seem to be a feature of boron chemistry.

It seems to me we have learnt enough to realise the futility of interstellar travel. So I think advanced aliens would not be so thick as to try to visit physically at all. Either they would rely on robots, sent on multi-millennium missions, or else on remote sensing methods. If the latter, we might never know of their interest.

Yes I think the problem with Freud is that his theories didn’t really make testable predictions. He could theorise about the reasons for something after the event, but he couldn’t find a child that not been hugged, say, and correctly predict it’s behaviour without knowing it beforehand. It all seems to be ex post facto explanation. Mind you, I sometimes get a bit queasy about certain rationalisations of behaviour in chemistry, for similar reasons. For instance, One can read qualitative explanations of why Hg is a liquid at r.t.p., but I’m not sure any theory is capable of predicting that outcome exactly. With very complex systems in science, one can get a fair amount of rationalisation after the event.

I’m with @Ken Fabian on this. Einstein et al weren’t trying to disprove the theory. They wanted to test it to see if it gave correct predictions or not. Falsifiability does not mean you have to try to falsify a theory, just that for a theory to be science it must be testable in a way that is capable of showing it false if its predictions are not borne out by observation.

No. What’s the link? It looks spammy. Set my mind at rest on that and maybe we can discuss why boron is not a great candidate for biochemistry.

My degree, my career, at least in part, and a lifelong interest.

Quite. The book is old news and was discredited years ago, as the Wiki article on it explains: https://en.m.wikipedia.org/wiki/Darwin's_Black_Box Behe* has had no credibility since his appearance at the Kitzmiller / Dover School trial, back in 2005. Basically, the pseudoscience of “Intelligent Design” is dead, but the corpse still twitches from time to time when people surface from the creationist community. * though he still seems to have tenure at Yee-Haa university or somewhere..............

Your ignorance is showing. Nobody uses carbon dating for objects more than a few thousand years old. I won’t bother with your other statements. Posting this level of junk on a science forum is pointless.

Yes I think that’s about right. Let’s see if our poster is willing to argue some specific points of contention here on the forum. My guess is he won’t want to try.

It seems vanishingly unlikely. As, by your own admission, you can’t be bothered to read what Darwin wrote, why would anyone take seriously a book recommended by you criticising his ideas? in any case, criticising Darwin is of little interest to scientists. Science has moved on quite a bit in the 150 years since Origin of Species came out. You seem to be flogging a dead horse.

It must have been some sort of trial of behaviour in which it was important that the feeding intervals were truly randomised, to exclude the possibility that the pigeon could be acting in response to some other, time-related, factor, or something.

Excited I don’t know, as I don’t follow abiogenesis research enough to know how radical this finding is. But if mafic glasses available on the surface of the Hadean earth can catalyse RNA polymerisation, that has to be an important piece of the jigsaw. Are there models for where the nucleoside phosphate monomers could have come from?

Suggest you try the test I recommended, by changing the angle of illumination and watching what happens to the colours as you do so. Rotating the specimen slowly may do the trick. If the colours are due to diffraction, as both @sethoflagos and I are proposing, you should see them changing. I think it unlikely that Iridium is responsible. The colours after which it was named were not those of minerals, but colours of the halides in various oxidation states when the element was dissolved in "marine acid" (HCl). The explanation of oxidation of the surface to goethite seems far more likely.

Energy does not have a direction. That should be obvious to you, if you think about it clearly.

Bingo! Well done. Prompted by your response to look up goethite, I found this: https://www.rockngem.com/iridescence-understanding-the-rainbow-in-the-mineral-world/ , which also explains the iridescence is indeed due to interference from microscopic surface irregularities. So now it seems we have a fairly complete explanation.

Yes. This poster has been posting blogs like this for at least five years now, in various places. It has never made any sense and it still doesn't. He makes no effort to interact with readers who ask questions or make observations, just carries on blogging regardless.

Suggest you look it up on the web first, and then revert here with any more specific issues you want to discuss.

But since that would be silly, that can't be what science is saying. I'm not a cosmologist but as I understand it, the age can be estimated, in the Big Bang model, from the temperature of the observed cosmic background radiation and the observed cosmological red shift. The temperature tells you how much space has expanded since the "surface of last scattering", which was the point at which it would have been effectively emitted, while the cosmological red shift gives you an expansion rate. Put the two together and you have an age estimate, back to the surface of last scattering. Extrapolating back from that on the basis of general relativity, you end up with a singularity about 300,000years earlier. So the model is based on observations of features of the universe that we have reason to think would be general, rather than specific to what we can observe with current technology. It is quite good at accounting for other observed features of the observable universe as well. There is more about it here: https://en.wikipedia.org/wiki/Lambda-CDM_model

These look like high magnification pictures of the same pyrite specimens you showed us earlier. The iridescent colours look to me as if they could be due to interference fringes, caused by diffraction arising from surface irregularities. You might be able to test this by seeing if the colours change as you move the source of illumination, so that the angle of incidence of the the light changes.

What has this to do with power? ?

Bye.

As I recall, when a non-fluorophore is excited by absorption of radiation, it can lose energy in a number of ways that are non-radiative. These will include collisional deactivation and also in some cases bond-breaking (e.g. if excitation is to a state involving a suitable antibonding orbital). I'm not sure I've seen the word "phosphorophore", but some molecules lose energy radiatively, not by fluorescence but via intersystem crossing to a triplet state, emission from which is known as phosphorescence rather than fluorescence. Conjugated organic molecules are far from the only compounds that can fluoresce*, but their extensively delocalised π-orbitals have fairly low lying excited states that often emit in the visible region of the spectrum without bond-breaking (the σ-bond will hold the molecule together when various π* modes are excited). Since the Stokes shift is something observed when a compound fluoresces, I'm not sure how it can be used to predict whether or not something will fluoresce. I'm afraid I don't know anything about the use of fluorescent molecules in biochemistry (I'm sure others here may), but it is to be expected that some organic molecules may be able to bind to nucleic acids, so synthesising one containing a fluorophore is not hard to envisage in principle. *The word fluorescence comes from the visible glow from fluorite (CaF₂) when it contains certain impurities, under UV illumination. Many minerals fluoresce.

Are they especially colourful? I think Ir compounds are mostly oxidation state +3 or +4 and quite a few of them are black or dark brown. But frankly Ir is not an element I know much about. Which salts do you have in mind?

Hmm, good as far as it goes, but my understanding was that the acidification of the oceans caused by higher atmospheric CO2 tends to make survival harder for all corals. Presumably this effect is global and not confined to warm waters.