I've seen this blow up in several places now, but there seriously is nothing to this paper.<p>Essentially all they're pointing out is that the set of atomic transition energies (1) is positive, (2) has a smooth distribution, (3) goes to zero at zero and infinity, (4) has a maximum somewhere in between, (5) is skewed right. All of these things are completely mundane and well-understood, and not at all unique to the "Planck distribution". Statisticians probably know of tens of other distributions with these properties, which would fit their curve about as well.<p>Their claim is like saying that <i>any</i> function that goes from -1 to 1 smoothly must be a logistic function, or <i>any</i> function that goes to 0 at infinity but slowly must be a power law. That's not a paper, that's a hunch. If the researchers wanted to be serious, they could have run a statistical test to quantify how well the data fit the Planck distribution (just like tests of normality are routinely done in statistics). But they didn't, and the reason probably is because the test would fail.
The correlation between global distribution of all experimentally known atomic spectral lines to the Planckian spectral distribution associated with black body radiation at a temperature of 𝑇≈9000K is indeed "funny". The match seems close enough to be worth investigation.<p>On the other hand the observation that "This value coincides with the critical temperature of equilibrium between the respective densities of radiation and matter in the early universe" seems spurious and is unsupported by anything in the paper.<p>I would expect rather there is some quirky statistics that happen with the quantum mechanics of orbitals that gives a similar shaped distribution of frequency of occurrence of spectral lines to the Boltzman distribution.<p>There is probably an interesting statistical story to tell, but I don't see the connection to the early universe as a supported thing here.
Thinking out loud:<p>When the universe was at 9000K, the vast majority of these elements did not exist or only existed at negligible concentration. Look up “Big Bang nucleosynthesis”. It would be interesting to see if the result is reproduced at all when looking at only light elements.<p>Of course the bin width makes little difference. Bigger bins would just smooth the curve.<p>There is probably a huge bias in that this looks at transitions that are interesting to the NIST database. As the authors allude, there are huge numbers of transitions that almost, but don’t quite, ionize at atom. Similarly, there are huge numbers of X-ray transitions in which inner electrons are kicked to very high levels or removed entirely. I don’t know to what extent the latter is well represented in the database.<p>For that matter, there are transitions between bound states and unbound states. Imagine that you light up Hydrogen at 13.6 eV plus a little bit. I think you can still eject elections — the excess energy can be carried away as kinetic energy. (There can be issues with simultaneously conserving energy and momentum.). The unbound states are genuinely continuous.<p>I didn’t look for real, but the NIST data has too many entries to represent just the spectra of cold atoms. I have a sneaking suspicion that researchers are measuring emissions from hot gasses or plasmas, perhaps heated near 9000K.
The authors have a look at the spectral line database of the NIST and make the surprising finding, that all atomic spectral lines together approximate very well a black body spectrum at a temperature of 9000K.<p>The authors not yet have an explanation for this conundrum, but also note, that this temperature plays a role in the formation theory of the universe.
From the same paper, I'm not sure this passage helps its case. It seems off-topic, and rather breathless in it's speculation, although I respect their positive imagination:<p><i>An entirely different yet equally fascinating possibility would be that, in an abstract sense, the scientific community itself can be interpreted as a thermodynamic ensemble. In this line of thinking, the individual members would be subject to a Boltzmann distribution in “curiosity” associated with a “temperature” determining how likely each researcher is to carry out research more or less closely tethered to a specific area of interest. In turn, a type of entropy could be associated with the amount of information contained in this ensemble, or exchanged between sufficiently large subsets of it. If correct, the implications would be truly profound, and could reshape the future direction of science in ways never before imagined. Understanding the mechanisms with which to influence the “curiosity temperature” would allow wise policy makers to implement suitable conditions that foster scientific progress, and usher in a new era of discovery...[goes on at length]</i>
+1 Full text of the article is available for free.<p>Challenge to HN community: Let's make a serious effort to understand exactly what the paper says before either throwing rocks or talking about how awesome it is.
Years ago, i read a paper that looked at a database of all known organic molecules, and found that a disproportionate number of them had an even number of carbon atoms. I can't find it now, of course.<p>The paper was a similar "that's funny, i wonder why" sort of piece. The tentative explanation i remember is that a lot of those organic molecules are natural products, and the nature of biosynthetic pathways is that they tend to add carbons two by two. Which i don't think is even true - terpenoids are built five carbons at a time.
The authors describe an observation of similarity between two plots of completely different things. That could be an interesting paper, if they investigated this similarity with some skepticism and the similarity was shown to be robust, independent of the particular choices they made (bin width, choice of the subset of all spectral lines).<p>But they apparently did not do their job. Instead, they indulge in speculations about even crazier connections with a past state of the universe or with behaviour and biases of scientific community.<p>This kind of half-baked observation and speculation is an interesting discussion topic for a lunchtime that can potentially lead to something substantial, but really should not be published as scientific paper.<p>Also this paper is a good example of what is wrong with physics academia (and perhaps other academic workers as well). 4 authors, 18 references to other people work, and a statement of conflict of interest.<p>Sad state of physics, year 2020.
A couple of days ago, there also has been a disussion on reddit on this topic.<p><a href="https://www.reddit.com/r/Physics/comments/gf1kbd/if_you_overlay_all_atomic_spectra_you_get_a/?sort=new" rel="nofollow">https://www.reddit.com/r/Physics/comments/gf1kbd/if_you_over...</a>
Very cool finding that IMHO goes beyond coincidence. Some are saying the authors compared "two completely different plots" - this is a strange thing to say. Both plots have an X axis of wavelength, that's obviously the same. There's some ambiguity of the units on the Y axis, since the BB is in W/m^3 while histogram is unitless.<p>However it's really not a stretch to consider the BB as some relative intensity. So it's totally reasonable to overlay these plots.<p>A possible way to reconcile this would be to model some gas mixture composition and determine the aggregate spectra of that, and that would be in W/m^3.<p>E: downvote(s), do you have a rebuttal, or just think I'm wrong?
Worth keeping in mind that the blackbody emission curve is generated by some pretty simple equations, multiplying the higher density of states at higher energies with the lower probability of states being occupied at higher energies. Not surprising that something similar (exponential suppression of X via the pontryagin dual of X) would show up in other contexts, so I think “coincidence” is actually pretty likely.
Jesus, physics has gotten REALLY BAD indeed. This is clown car tier.<p>If you overlay all atomic spectra, you expect the result to be something like Gaussian Unitary Ensemble (aka eigenvalues of a random matrix), which looks much like the Planck distribution. Nothing to do with matter in the early universe; most atoms didn't exist in the early universe. TLDR; contemporary physicists fail at elementary statistical distributions, and, like, common sense.