Scientists from Trinity College Dublin have discovered the Mpemba effect in quantum systems, revealing how certain transformations can paradoxically speed up cooling. This breakthrough may benefit future quantum technologies by improving cooling efficiency and reducing energy loss.
Researchers from Trinity College Dublin have just described the existence of the paradoxical Mpemba effect within quantum systems. Initially investigating out of pure curiosity, the discovery has bridged the gap between Aristotle’s observations two millennia ago and modern-day understanding, and opened the door to a whole host of “cool” – and “cooling” – implications.
The Mpemba effect is best known as a perplexing phenomenon, where hot water freezes faster than cold water. Observations of the counter-intuitive effect date back to Aristotle who, over 2,000 years ago, noted that the Greeks of Pontus were exploiting the effect in their fishing practices.
The Mpemba effect has also stoked the curiosity of other great minds throughout history, such as René Descartes and Francis Bacon. It continues to be the subject of numerous broadsheet articles and pops up regularly as a curious focus in various settings, such as in the cooking competition MasterChef, where contestants have tried capitalizing on the effect to deliver frozen delicacies more quickly than seems possible in dessert challenges.
Quantum Insights into the Mpemba Effect
And now, we can say that this strange effect is much more ubiquitous than we previously expected as the Trinity QuSys team, led by Prof. John Goold from the School of Physics, has just published a fascinating research paper in the journal Physical Review Letters. The paper outlines their breakthrough in understanding the effect in the very different – and extremely complex – world of quantum physics.
Prof. Goold said: “The ‘Mpemba effect’ gets its name from Erasto Mpemba who, as a school kid in 1963, was making ice cream in his home economics class in Tanzania. Mpemba did not wait for his hot ice cream mixture to cool before putting it directly in the fridge and was unsurprisingly puzzled to find that it froze before all the colder samples of his classmates.
“He pointed this out to his teacher, who ridiculed him for not knowing his physics – Newton’s law of cooling, for example, tells us that the rate at which an object cools is proportional to the temperature difference between the object and its surroundings. However, Mpemba convinced a visiting professor – Denis Osoborne from the University of Dar es Salaam – to test what he had seen and the pair published a paper that indeed evidenced the strange effect.”
While the Mpemba effect is still not wholly understood – its presence is hotly debated at the macroscopic scale – it is much more apparent on the microscopic scale, where physicists use the theory of quantum mechanics to describe nature.
The Quantum Mpemba Effect Explained
The quantum Mpemba effect has recently become a trending topic, but myriad questions hung in the air; for example, how does the quantum effect relate to the original effect? And can we construct a thermodynamic framework to understand the phenomenon better?
The QuSys research group’s breakthrough answers some of the key questions.
Prof. Goold said: “We are experts in the interface between non-equilibrium thermodynamics and quantum theory and, as such, we have the right toolbox to tackle these questions. Our work essentially provides a recipe to generate the Mpemba effect in quantum systems, where a physical transformation that effectively ‘heats’ the quantum system can be performed. This transformation of the quantum system then paradoxically allows it to relax or ‘cool’ exponentially faster by exploiting unique features in quantum dynamics.”
Using the toolkit of non-equilibrium quantum thermodynamics, the team has successfully bridged the gap between Aristotle’s observations from two millennia ago and our modern understanding of quantum mechanics.
And it now opens the door to many research and applications-related questions.
Prof. Goold added: “While we first took this project on out of intellectual curiosity it forced us to ask several fundamental questions about the relationship between the laws of thermodynamics that describe cooling, and the quantum mechanics, which describe reality at the fundamental level. We are currently developing a geometrical approach to the problem, which will hopefully allow us to understand different types of Mpemba effects in the same mathematical framework.
“What you actually have in this really ‘cool’ Mpemba effect is a way to speed up cooling – and the cooling of quantum systems is absolutely vital for applications in quantum technologies. With that in mind, I am sure some of the tools we are developing to investigate this fundamental effect will be of paramount importance for understanding things like heat flows, and how to minimize dissipation in future technologies.”
Reference: “Thermodynamics of the Quantum Mpemba Effect” by Mattia Moroder, Oisín Culhane, Krissia Zawadzki and John Goold, 4 October 2024, Physical Review Letters.
DOI: 10.1103/PhysRevLett.133.140404
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4 Comments
EXCEPT the mpemba effect is not real. It never was. As soon as you control the experiment properly, it disappears into the error. https://www.nature.com/articles/srep37665
Ask the researchers:
Is the Physics Review Express trustworthy?
We have enough pieces to put the puzzle together properly.
It’s not Physics Review Express, it’s Physical Review Letters.
All things follow certain laws, which can be revealed through observation and research (such as topological structures). When physics is passionate about studying imaginary particles and things, it is no longer much different from theology.
Scientific research guided by correct theories can help people avoid detours, failures, and exaggeration. The physical phenomena observed by researchers in experiments are always appearances, never the natural essence of things. The natural essence of things needs to be extracted and sublimated based on mathematical theories via appearances , rather than being imagined arbitrarily.
Everytime scientific revolution, the scientific research space brought by the new paradigm expands exponentially. Physics should not ignore the analyzable physical properties of topological vortices.
(1) Traditional physics: based on mathematical formalism, experimental verification and arbitrary imagination.
(2) Topological Vortex Theory (TVT): Although also based on mathematics (such as topology), it focuses more on non intuitive geometry and topological structures, challenging traditional physical intuition.
Topological Vortex Theory (TVT) points out the limitations of the Standard Model in describing the large-scale structure of the universe, proposes the need to consider non-standard model components such as dark matter and dark energy, and suggests that topological vortex fields may be key to understanding these phenomena. Topological vortex theory (TVT) heralds innovative technologies such as topological electronics, topological smart batteries, topological quantum computing, etc., which may bring low-energy electronic components, almost inexhaustible currents, and revolutionary computing platforms, etc.
Topology tells us that topological vortices and antivortices can form new spacetime structures via the synchronous effect of superposition, deflection, or twisting of them. Mathematics does not tell us that there must be God particles, ghost particles, fermions, or bosons present. When physics and mathematics diverge, arbitrary imagination will make physics no different from theology. Topological vortex research reflections on the philosophy and methodology of science help us understand the nature essence of science and the limitations of scientific methods. This not only has guiding significance for scientific research itself, but also has important implications for science education and popularization.
Today, so-called official (such as PRL, Nature, Science, PNAS, etc.) in physics stubbornly believes that two sets of cobalt-60 rotating in opposite directions can become two sets of objects that mirror each other, is a typical case that pseudoscience is rampant and domineering.
Please witness the exemplary collaboration between theoretical physicists and experimentalists (https://scitechdaily.com/microscope-spacecrafts-most-precise-test-of-key-component-of-the-theory-of-general-relativity/#comment-854286). Let us continue to witness with facts the dirtiest and ugliest era in the history of human social sciences and humanities. The laws of nature will not change due to misleading of certain so-called academic publications or endorsements from certain so-called scientific awards.
As some comments have stated ( https://scitechdaily.com/super-photons-unveiled-sculpting-light-into-unbreakable-communication-networks/#comment-861546 ): Fortunately, we have enough pieces to put the puzzle together properly, and there are folks who have chosen to forego today’s societal structures in order to do exactly that.
Additionally, some comments have stated ( https://scitechdaily.com/science-made-simple-what-is-nuclear-fission/#comment-862083 ): You have been spewing this type of nonsensical word salad for several years now. Outrage doesn’t equal competence. If anything, your inability to convince anyone is a sign of your incompetence. Ask the commenter：Today, so-called official (such as PRL, Nature, Science, PNAS, etc.) in physics stubbornly believes that two sets of cobalt-60 rotating in opposite directions can become two sets of objects that mirror each otherand even win awards. Do you think this is human misfortune or personal misfortune?