How chaos theory mediates between quantum theory and thermodynamics
Dec 2022, phys.org
Sounds important, not sure I understand:
When a large number of quantum particles are in play at the same time, the equations of quantum theory become so complicated that even the best supercomputers in the world have no chance of solving them [and therefore we can't get temperature from quantum particles, only classical ones].
Only where chaos prevails do the well-known rules of thermodynamics follow from quantum physics [according to their super-simulations].
[They describe a system as behaving "quantum chaotically".]
This is one of the first cases in which the interplay between three important theories has been rigorously demonstrated by many-particle computer simulations: quantum theory, thermodynamics and chaos theory.
via Institute of Theoretical Physics at Vienna University of Technology: Mahdi Kourehpaz et al, Canonical Density Matrices from Eigenstates of Mixed Systems, Entropy (2022). DOI: 10.3390/e24121740
Researchers discover superconductive images are actually 3D and disorder-driven fractals
May 2023, phys.org
"Electronic fractals" it's being called. And I guess we already know this: "Advancements with superconductivity hinge on advances in quantum materials. When electrons inside of quantum materials undergo a phase transition, the electrons can form intricate patterns, such as fractals."
But now, with better, higher resolution imaging, they see that the fractals are not just on the surface, but indeed 3-dimensional, so the entire crystal is made of them.
Sudden implication: "Correlation length -- the distance over which the nematic order maintains coherence -- is larger than the field of view of the experiment" (because you know fractals are fractional dimensions that seem to "steal" space from the higher dimension).
In case you were wondering: Superconductor Bi2-xPbzSr2-yLayCuO6+x (BSCO), that's it's name.
via Purdue, Harvard, University of Illinois at Urbana-Champaign, and Penn State: Can-Li Song et al, Critical nematic correlations throughout the superconducting doping range in Bi2-xPbzSr2-yLayCuO6+x, Nature Communications (2023). DOI: 10.1038/s41467-023-38249-3
The brain's ability to perceive space expands like the universe
Jan 2023, phys.org
Salk scientists have discovered that time spent exploring an environment causes neural representations to grow in surprising ways.
Neurons in the hippocampus essential for spatial navigation, memory, and planning represent space in a manner that conforms to a nonlinear hyperbolic geometry—a three-dimensional expanse that grows outward exponentially.
The size of that space grows with time spent in a place, increasing in a logarithmic fashion that matches the maximal possible increase in information being processed by the brain.
via the Salk Institute: Huanqiu Zhang et al, Hippocampal spatial representations exhibit a hyperbolic geometry that expands with experience, Nature Neuroscience (2022). DOI: 10.1038/s41593-022-01212-4
See also: New research finds that collective neural activity is shaped like the surface of a doughnut via Norwegian University of Science and Technology's Kavli Institute for Systems Neuroscience: Richard J. Gardner et al, Toroidal topology of population activity in grid cells, Nature (2022). DOI: 10.1038/s41586-021-04268-7
And: New method to determine the dimensionality of complex networks through hyperbolic geometry via University of Barcelona: Pedro Almagro et al, Detecting the ultra low dimensionality of real networks, Nature Communications (2022). DOI: 10.1038/s41467-022-33685-z
Fractons as information storage: Not yet tangible, but close
May 2023, phys.org
Fuck is a fracton come on man (we're copying most of the article here, dense stuff)
Fractons are fractions of spin excitations and are not allowed to possess kinetic energy. As a consequence, they are completely stationary and immobile. This makes fractons new candidates for perfectly secure information storage. Especially since they can be moved under special conditions, namely piggyback on another quasiparticle.
"Fractons have emerged from a mathematical extension of quantum electrodynamics, in which electric fields are treated not as vectors but as tensors -- completely detached from real materials"
In order to be able to observe fractons experimentally in the future, it is necessary to find model systems that are as simple as possible: Therefore, octahedral crystal structures with antiferromagnetically interacting corner atoms were modeled first.
(Obviously)
...included quantum fluctuations in the calculation of this octahedral solid-state system for the first time, and see they do not enhance the visibility of fractons, but on the contrary, completely blur them, even at absolute zero temperature
via Helmholtz Association of German Research Centres, Indian Institute of Technology in Chennai: Nils Niggemann et al, Quantum Effects on Unconventional Pinch Point Singularities, Physical Review Letters (2023). DOI: 10.1103/PhysRevLett.130.196601
Punctuation in literature of major languages is intriguingly mathematical
Apr 2023, phys.org
First, can someone just tell me how an institute of nuclear physics started doing research on punctuation usage?
Punctuation turns out to be a universal and indispensable complement to the mathematical perfection of every language studied.
Thanks.
And this isn't their first study on the topic:
"The present analyses are an extension of our earlier results on the multifractal features of sentence length variation in works of world literature. After all, what is sentence length? It is nothing more than the distance to the next specific punctuation mark— the full stop. So now we have taken all punctuation marks under a statistical magnifying glass, and we have also looked at what happens to punctuation during translation,"
The attention of the Cracow researchers was primarily drawn to the statistical distribution of the distance between consecutive punctuation marks. It soon became evident that in all the languages studied, it was best described by one of the precisely defined variants of the Weibull distribution.
The Weibull distribution is usually used to describe survival phenomena (e.g. population as a function of age), but also various physical processes, such as increasing fatigue of materials.
Further findings:
The language characterized by the lowest propensity to use punctuation is English, with Spanish not far behind; Slavic languages proved to be the most punctuation-dependent. German proved to be the exception. Its hazard function is the only one that intersects most of the curves constructed for the other languages. German punctuation thus seems to combine the punctuation features of many languages, making it a kind of Esperanto punctuation. Also, the language most faithfully transforming punctuation from the original language to the target language turned out to be German.
And here is just a great explanation of the mathematical constraints on language:
"Creating a sentence by adding one word after another while ensuring that the message is clear and unambiguous is a bit like tightening the string of a bow: it is easy at first, but becomes more demanding with each passing moment. If there are no ordering elements in the text (and this is the role of punctuation), the difficulty of interpretation increases as the string of words lengthens. A bow that is too tight can break, and a sentence that is too long can become unintelligible. Therefore, the author is faced with the necessity of 'freeing the arrow', i.e. closing a passage of text with some sort of punctuation mark. This observation applies to all the languages analyzed, so we are dealing with what could be called a linguistic law," states Dr. Tomasz Stanisz (IFJ PAN), first author of the article in question.
Also: The Journal of Chaos, Solitons and Fractals
via The Henryk Niewodniczanski Institute of Nuclear Physics Polish Academy of Sciences: Tomasz Stanisz et al, Universal versus system-specific features of punctuation usage patterns in major Western languages, Chaos, Solitons & Fractals (2023). DOI: 10.1016/j.chaos.2023.113183
Harnessing chaos - Simulation experiment demonstrates way to mitigate extreme weather events
Jun 2023, phys.org
Is this even real? This is the most sci fi shit I've ever heard. Diabolical, and if it wasn't from RIKEN, I wouldn't even post it; it was also part of a national competition in Japan:
RIKEN scientists have demonstrated a way to make small tweaks in weather systems as a means to prevent, or at least reduce, the severity of extreme weather events such as torrential rain. They did this by taking advantage of the chaos that is inherent to such systems. Through this work they hope to develop ways to prevent extreme weather events, which have become more common in recent years.
His group took on this challenge as part of the Japanese government's moonshot-millennia program, and in previously published work, they described the possibility of controlling weather by initiating small changes in it as it forms. At that time, they used the simple Lorenz 63 weather model, which only has a few variables, and showed that it would be possible to induce small perturbations in the system to keep it on one side of a so-called "butterfly pattern." (I don't know why they're not calling it the butterfly effect)
Their new study published in Nonlinear Processes in Geophysics goes beyond the simple model. In it, the team adopted the Lorenz 96 model. Essentially, it sets a weather variable for 40 points along a line of latitude around the Earth, and looks at how each of these points changes as it interacts with neighboring points throughout the year. Approximately once or twice a year, the points show large variations, which correspond to extreme weather events. As part of a control simulation experiment, the members of the team were able to eliminate the extreme events by making small tweaks in a 100-year run of the model.
The control simulation experiment essentially took advantage of the chaotic nature of the system; small perturbations—which might for example involve making centimeter/second changes in wind speed to prevent a typhoon with winds that are many times more powerful—done strategically ahead of time could prevent the system from entering an undesired area, meaning that they could stop extreme events from happening.
via RIKEN: Qiwen Sun et al, Control simulation experiments of extreme events with the Lorenz-96 model, Nonlinear Processes in Geophysics (2023). DOI: 10.5194/npg-30-117-2023
