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Full Version: Copernicium is a strange element indeed
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https://blogs.sciencemag.org/pipeline/ar...ent-indeed

EXCERPT: . . . let’s talk about ... the element copernicium. That’s #112, just below mercury in the periodic table, and its longest-lived isotope has a half-life of 29 seconds ... it’s long enough that if you look smart you can actually study its properties and its chemistry a bit. Why would anyone want to do that (“Because I have a grant” is not the answer we’re looking for here)? Well, it’s because of how strange mercury is. Like the properties of water, the properties of mercury actually have come to seem weirder and weirder to me as I learn more chemistry and physics.

[...] it wasn’t until 2013 that Peter Schwerdtfeger ... and colleagues at other centers were able to nail down that the exact contribution to mercury’s melting point. (I may have mentioned this before, but I’ve long thought that a book titled “Quantum Mechanics: A Hand-Waving Approach” would sell quite well in the textbook market). Without relativistic corrections, mercury’s melting point is predicted to be 82C, rather than -39...

And now Schwerdtfeger and colleagues have turned to copernicium. Those effects that make mercury’s outer electrons less attentive to the outside world would be predicted to be even stronger in copernicium, leading to predictions in the 1970s that it would be practically inert. But in 2008, experimental evidence came in that the element (which at the time was unnamed!) had more metallic character than expected, via interaction with a gold surface. The new calculations, though ... strongly suggest that this result was due to dispersion forces. Copernicium, the authors believe, almost certainly has noble-gas characteristics and indeed may only barely be a liquid at room temperature (!) The new paper refers to it as a “relativistic noble liquid”, which is quite a weird category – it’s even more like mercury than mercury is.

Relativistic quantum effects are also the reason for gold being yellow and for lead-acid batteries being able to work at all ... No one makes batteries out of tin, and that’s what lead would be like, electrochemically, if it weren’t for the relativistic changes. I find the whole intersection of the two fields very interesting – not least because this is special relativity crossing with quantum mechanics as opposed to general relativity (both of which get referred to commonly as just “relativity”).

And there’s an interesting point: quantum mechanics predicts extremely counterintuitive and unusual phenomena, which have been observed exactly as predicted and to extraordinary levels of accuracy. Special relativity, likewise: it predicts wild things which have been experimentally verified from a great many different angles and in extreme detail. So it’s perhaps no surprise that the two get along fine. General relativity as well makes crazy-sounding predictions which also have stood up perfectly to every single experimental test, starting with the bending of light in the 1919 eclipse and going on to this day with the observation of gravitational waves. But general relativity and quantum mechanics. . .oh, boy.

When it comes to gravity, the two theories are completely incompatible, and there is no way to escape the conclusion that one or both of them must be seriously incomplete or even flat-out wrong about something important. There is no quantum theory of gravity as yet, despite huge amounts of brainpower being expended on the problem. A new understanding is out there somewhere, one that encompasses both of these hugely successful and powerful current theories and then shows something even larger and more powerful behind them both. And we don’t know what it is. The disputes about what the next physics will look like have attained near-religious intensity (and money has changed hands more than once), and who knows when it will ever be resolved? (MORE - details)