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This topic is available for members who might wish to collect information about the Carnot Heat Engine, and more importantly from my perspective, the interface between random molecular motion which is described by Carnot, and the movements of quantum level objects such as electrons, inside quantum level objects such as atoms.
It is my understanding, (always subject to correction as information arrives), that quantum transitions are NOT subject to Carnot. Such transitions (apparently) occur with 100% efficiency.
A solid understanding of both realms may (under the right circumstances) lead to improved performance of designed systems in the Real Universe.
I am inviting Calliban to set the stage for Carnot, with a post showing links to accessible explanations, and perhaps with personal observations to help readers.
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https://www.msn.com/en-us/news/technolo … d125&ei=12
The article at the link above offers a high level view of recent quantum research.
Physicists Discovered a Quantum Trick For Reaching Absolute Zero
Story by David Nield • Yesterday 2:00 PM
ScienceAlert© Provided by ScienceAlert
The state of perfect stillness known as absolute zero is one of the Universe's impossible achievements. As close as we can get, the laws of physics will always prevent us from hitting thermal rock bottom.An international team of researchers has now identified a new theoretical route to reach the mythical mark of zero Kelvin, or -273.15 degrees Celsius (-459.67 degrees Fahrenheit). No, it's not more likely to break any laws and remove every last shimmer of heat, but the framework could inspire new ways of exploring matter at low temperatures.
As a consequence of the third law of thermodynamics, the removal of increments of heat energy from a group of particles to cool them to absolute zero will always take an infinite number of steps. As such, it requires an infinite amount of energy to achieve. Quite the challenge.
Classical physics makes this relatively obvious. Viewed in the context of quantum physics, however, the problem begins to look a little different.
Quantum physics describes particles according to a spread of possibilities. Only once a feature is measured does it have a concrete state, and even then, other qualities of the particle become a little less certain. A particle at the theoretical point of absolute zero would have no movement, meaning its position would be certain. Quantum details regarding its prior position would effectively be wiped, deleting information.
Enter Landauer's principle, which states that deleting a piece of information requires a minimum and finite amount of energy.
Does that mean there is a quantum trick to dropping to zero after all?
There are two solutions to the paradox. An infinite amount of time or energy could still be required to make that leap. Or – as per the new research – it would require the deletion of an infinite amount of complexity.
It's this new revelation of the role of complexity that presents a new angle to the search for a pathway to absolute zero, even if it is as practically impossible as a solution as the ones scientists have already been working with.
"We found that quantum systems can be defined that allow the absolute ground state to be reached even at finite energy and in finite time – none of us had expected that," says particle physicist Marcus Huber, from the Vienna University of Technology in Austria.
"But these special quantum systems have another important property: they are infinitely complex."
What we now have is essentially a 'quantum version' of the third law of thermodynamics that goes beyond what classical physics teaches us: an infinite amount of energy, time, or complexity is required to get to absolute zero.
The calculations and modeling carried out by the team also show that the perfect erasure of data and the lowest possible temperature are closely linked, and both apparently impossible to achieve by we mere mortals.
It's possible then that increasing complexity in systems is another way of getting closer to absolute zero, or at least proceeding more quickly.
"If you want to perfectly erase quantum information in a quantum computer, and in the process transfer a qubit to a perfectly pure ground state, then theoretically you would need an infinitely complex quantum computer that can perfectly control an infinite number of particles," says Huber.
In practical terms, no computer system is ever perfect – so the idea that a particle in a quantum computer could never be fully wiped of its data (or previous states) shouldn't be a stumbling block in the development of these technologies.
Quantum mechanics and temperature are closely related – when we get close to absolute zero, strange quantum phenomena start happening – and the researchers say that this is another area where the findings of this study can be useful in the future.
"This is precisely why it is so important to better understand the connection between quantum theory and thermodynamics," says Huber. "There is a lot of interesting progress in this area at the moment. It is slowly becoming possible to see how these two important parts of physics intertwine."
The research has been published in PRX Quantum.
Despite the teaser, the bottom line is you ** still ** can't reach absolute zero.
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https://www.msn.com/en-us/news/technolo … c49d&ei=32
Here is a shorter link to what appears to be the same story:
https://bigthink.com/hard-science/brain … anglement/
The Premier Daily
Brain experiment suggests that consciousness relies on quantum entanglement
Story by Julie Hambleton • Yesterday 2:41 PMThe Premier Daily
Brain experiment suggests that consciousness relies on quantum entanglement
Brain experiment suggests that consciousness relies on quantum entanglement
© Provided by The Premier DailyAsk a neuroscientist, and they will tell you this: We still know very little about the brain; how it functions, how it functions, etc. Up until now, the belief was that the brain is a classical system. This new research out of Trinity College in Dublin, Ireland, challenges that. Their research shows that quantum entanglement may, in fact, be at work in our brains.
Quantum Computation and the Enigma of Brain Entanglement
In a groundbreaking study conducted by scientists at Trinity College Dublin, a remarkable connection between the mysteries of quantum computation, or gravity, and the intricate workings of our brains has been unearthed. Utilizing a revolutionary technique to test for quantum gravity, the researchers have postulated that the phenomenon of entanglement might be at play within our very own minds. This discovery holds immense implications for our understanding of consciousness, cognition, and the fabric of reality itself. (1)Unraveling Quantum Gravity
Quantum gravity, an elusive concept that lies at the intersection of quantum mechanics and general relativity, has long been considered the holy grail of modern physics. While quantum mechanics describes the micro world of atoms and subatomic particles, general relativity provides a framework for understanding gravity on a macroscopic scale. However, these two pillars of physics have proven to be fundamentally incompatible, leaving scientists with an enigmatic puzzle to solve.To further probe the depths of quantum gravity, the researchers at Trinity College Dublin devised an ingenious technique. By harnessing the power of high-energy particle collisions and sophisticated measurement equipment, they aimed to detect potential quantum gravitational effects on a macroscopic level.
“We adapted an idea, developed for experiments to prove the existence of quantum gravity, whereby you take known quantum systems, which interact with an unknown system. If the known systems entangle, then the unknown must be a quantum system, too. It circumvents the difficulties to find measuring devices for something we know nothing about," said Dr. Christian Kerskens, co-author of the study and lead physicist at the Trinity College Institute of Neuroscience.“For our experiments we used proton spins of ‘brain water’ as the known system. ‘Brain water’ builds up naturally as fluid in our brains and the proton spins can be measured using MRI (Magnetic Resonance Imaging). Then, by using a specific MRI design to seek entangled spins, we found MRI signals that resemble heartbeat evoked potentials, a form of EEG signals. EEGs measure electrical brain currents, which some people may recognize from personal experience or simply from watching hospital dramas on TV.” (2)
The Intriguing Role of Entanglement
Entanglement, an extraordinary phenomenon in quantum mechanics, occurs when two or more particles become correlated and share a dependent state regardless of the distance between them. This unique property has left scientists fascinated, with many pondering the extent of its reach in the macroscopic world.Building upon the notion that entanglement might extend beyond the realm of quantum mechanics, the Trinity College Dublin researchers have proposed a profound hypothesis. What if entanglement is not confined to the microscopic scale but also plays a critical role within the human brain?
Quantum Entanglement and Consciousness
It has long been suspected that consciousness, our subjective experience of the world, arises from the intricate interactions within our brain. But understanding the exact nature of consciousness has remained an enigma, with numerous theories vying for dominance.The suggestion that quantum entanglement might be at work in our brains provides a captivating new perspective. Imagine the countless neural connections in our brain acting in unison through entanglement, leading to the emergence of consciousness. This hypothesis opens up a deeper understanding of the mysteries of the mind and the interconnectedness of the universe.
Read: Mind-blowing Experiments Say That Reality Doesn't Exist If You Are Not Looking at It
Bridging the Gap: Neuroscience and Quantum Mechanics
To comprehend the potential quantum entanglement within our brains, we must bridge the gap between the fields of neuroscience and quantum mechanics. The Trinity College Dublin researchers propose that specific neural processes generate highly entangled states within our brain, paving the way for conscious experiences.Furthermore, recent advancements in neuroscience have unveiled evidence of coherent neural oscillations, suggesting that synchronous activity between different brain regions plays a vital role in cognition. Could it be that entanglement is responsible for maintaining these coherence patterns and facilitating the integration of information?
Consciousness: A Quantum Orchestra
Drawing parallels between the symphony of coherent neural activity and the harmonious dance of entangled particles in quantum systems, the researchers propose an analogy. Just as an orchestra requires synchrony and coordination among its musicians to create a captivating melody, consciousness might arise from the orchestrated interplay of entangled brain states.Implications and Future Directions
The implications of this groundbreaking research are monumental. If entanglement indeed plays a role in our brains, it challenges the conventional wisdom that consciousness solely emerges from classical biological processes. It also hints at the possibility of a deeper connection between our minds and the fundamental fabric of reality.Further studies are needed to delve deeper into the intricacies of brain entanglement and its relationship with consciousness. It will require interdisciplinary collaboration between physicists, neuroscientists, and philosophers to explore this captivating frontier of knowledge.
The Bottom Line
The exploration of quantum gravity and the suggestion of entanglement at work within our brains represent a convergence of science and philosophy. The researchers at Trinity College Dublin have opened Pandora’s box of profound questions and potential answers, shedding light on the interplay between quantum phenomena and the extraordinary realms of human consciousness.
As we continue to unravel the mysteries of quantum gravity and delve deeper into the enigma of brain entanglement, we move closer to comprehending the essence of our own existence and the true nature of reality itself.
Keep Reading: Scientific ex
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For SpaceNut ... we only have two topics that contain the word "quantum"....
This post seems like a reasonable fit for this topic ... it ** definitely ** involves quantum physics ..
The subject of the report is an advance in understanding of superconductivity, although the work seems to raise plenty of questions ...
https://www.yahoo.com/tech/u-govt-resea … 10548.html
Tom's Hardware
U.S. Govt and researchers seemingly discover new type of superconductivity in an exotic, crystal-like material — controllable variation breaks temperature recordsFrancisco Pires
Fri, December 22, 2023 at 11:15 AM EST·4 min read
8 commentsSuperconductor image.
A group of physicists from the University of Washington and the U. S. Department of Energy (DOE) have seemingly discovered a new, controllable variation of superconductivity in an exotic, crystal-like material. Its superconductivity can be modulated according to the strain applied to it, to the point of turning it off at will. Simultaneously, they've apparently broken the record on how "hot" a field-effect superconductor can be before it loses its ability to conduct electricity, absent any resistance.
What's a Superconductor?
LK-99 room-temperature levitating superconductor.
Superwhat? Here's what you need to know about superconductors, how they work, and why they're key to PCs.
The time hasn't yet come for the room-temperature, ambient-pressure superconductor, but a temperature record is a temperature record, even if it's (still) around the 10 K barrier (-263.5 ºC).
The research paper (published in Science Advances) describes a synthetic, crystal-like sandwich of both ferromagnetic (Europium) and superconductive materials (Iron Arsenide), which showcase emergent superconductivity when placed in the proximity of a strong enough magnetic field. Doped EuFe2As2, as the material is called due to the addition of Cobalt molecules to the synthesis process, takes advantage of Europium's (Eu) strong ferromagnetism, alternated with superconducting/nematic FeAs (Iron Arsenide) layers in a sandwich-like configuration.
The result is what's known as a field-tunable superconductor -- one whose superconductivity features can be enabled through the application of external magnetic fields. In the case of doped EuFe2As2 (and by deploying specialized equipment alongside a combination of X-ray techniques), the research team showed how a properly aligned external magnetic field counterbalances the magnetic fields emanating from the ferromagnetic Europium layers. This allows them to be reoriented - and once the originally chaotic magnetic fields are parallel to the superconducting ones, a zero-resistance state of matter emerges.
But doped EuFe2As2 has another secret: its superconducting capabilities can be turned off even in a strong enough magnetic field. All that's needed is to strain the material with a cryogenic strain cell - to apply pressure from a single side (uniaxially) with what's akin to an industrial, scientific-measurements-certified piston -- to modulate how much resistance electrons find while traversing it. Under certain strain levels, the superconductivity of the synthetic material can be boosted enough so that an external magnetic field isn't required to enable a superconductive state. But after a point, not even pressure gets the engines going. Two different mechanisms for superconductivity can only go so far, but they also open up several opportunities in customizing superconductivity -- an additional lever to pull.
A descriptor of the superconducting processes.
The researchers noted difficulties in their synthesis process despite the overwhelming quality of documentation (they did it themselves, after all). The research team wasn't able to discern what prevented viable samples of Cobalt-doped EuFe2As2 from resulting from the synthesis process; instead, they reported "substantial sample to sample variability," where variability refers to whether the samples presented field-induced superconductivity or not. The researchers further noted the difficulties likely arose in the Cobalt doping stage of the recipe, a confirmation of how difficult it is to control quantum processes (such as chemical reactions) at the level of precision some of these synthetic materials that are bearers of superconductivity require.
These are subtle, subatomic element changes and interactions -- that's truly all that's required for morphing a material from semiconductivity to superconductivity. But that simpleness hides a complex interaction of elements, particles and subatomic particles, spins, magnetic fields, and many more parameters in a way that's just right - or in the case of the researcher's samples, between 4 Kelvin and 10 Kelvin of rightness.
This level of resolution and control into the moment superconductivity gets "turned off" (which is the same as the moment it gets "turned on" but different, in a very quantum way) should provide invaluable insights into the quantum physics of superconducting. At the very least, the newly discovered superconductor can be a testbed for a better understanding of superconductivity itself -- being able to see the molecular transition from normal matter to its superconductive phase at higher and higher resolutions should increase our ability to control the effect and extract further usefulness from it.
And if anything, the book in condensed matter physics still has several blank pages to pour discoveries onto, this novel superconducting mechanism included. Not that it's hard to imagine places where perfectly-conducting circuits that never heat up would be great: Argonne National Labs states that this discovery could "find uses in superconducting circuits for next-generation industrial electronics." I'll take a Ryzen 15 Super Cooper, please.
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One take-away for me is that "room temperature" super-conductivity is still a ways off.
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https://www.yahoo.com/news/quantum-phys … 56433.html
The article at the link above provides an overview of quantum effects, and intoduces consideration of their effects in biological systems.
The Conversation
Quantum physics proposes a new way to study biology – and the results could revolutionize our understanding of how life works
Clarice D. Aiello, University of California, Los Angeles
Sat, December 23, 2023 at 10:17 AM EST·6 min read
233 commentsLooking at life at the atomic scale offers a more comprehensive understanding of the macroscopic world. <a href="https://www.gettyimages.com/detail/photo/colorful-model-of-helix-dna-strand-royalty-free-image/157531306" rel="nofollow noopener" target="_blank" data-ylk="slk:theasis/E+ via Getty Images;elm:context_link;itc:0" class="link rapid-noclick-resp">theasis/E+ via Getty Images</a>
Imagine using your cellphone to control the activity of your own cells to treat injuries and disease. It sounds like something from the imagination of an overly optimistic science fiction writer. But this may one day be a possibility through the emerging field of quantum biology.
Over the past few decades, scientists have made incredible progress in understanding and manipulating biological systems at increasingly small scales, from protein folding to genetic engineering. And yet, the extent to which quantum effects influence living systems remains barely understood.
Quantum effects are phenomena that occur between atoms and molecules that can’t be explained by classical physics. It has been known for more than a century that the rules of classical mechanics, like Newton’s laws of motion, break down at atomic scales. Instead, tiny objects behave according to a different set of laws known as quantum mechanics.
For humans, who can only perceive the macroscopic world, or what’s visible to the naked eye, quantum mechanics can seem counterintuitive and somewhat magical. Things you might not expect happen in the quantum world, like electrons “tunneling” through tiny energy barriers and appearing on the other side unscathed, or being in two different places at the same time in a phenomenon called superposition.
I am trained as a quantum engineer. Research in quantum mechanics is usually geared toward technology. However, and somewhat surprisingly, there is increasing evidence that nature – an engineer with billions of years of practice – has learned how to use quantum mechanics to function optimally. If this is indeed true, it means that our understanding of biology is radically incomplete. It also means that we could possibly control physiological processes by using the quantum properties of biological matter.
Quantumness in biology is probably real
Researchers can manipulate quantum phenomena to build better technology. In fact, you already live in a quantum-powered world: from laser pointers to GPS, magnetic resonance imaging and the transistors in your computer – all these technologies rely on quantum effects.
In general, quantum effects only manifest at very small length and mass scales, or when temperatures approach absolute zero. This is because quantum objects like atoms and molecules lose their “quantumness” when they uncontrollably interact with each other and their environment. In other words, a macroscopic collection of quantum objects is better described by the laws of classical mechanics. Everything that starts quantum dies classical. For example, an electron can be manipulated to be in two places at the same time, but it will end up in only one place after a short while – exactly what would be expected classically.
In a complicated, noisy biological system, it is thus expected that most quantum effects will rapidly disappear, washed out in what the physicist Erwin Schrödinger called the “warm, wet environment of the cell.” To most physicists, the fact that the living world operates at elevated temperatures and in complex environments implies that biology can be adequately and fully described by classical physics: no funky barrier crossing, no being in multiple locations simultaneously.
Chemists, however, have for a long time begged to differ. Research on basic chemical reactions at room temperature unambiguously shows that processes occurring within biomolecules like proteins and genetic material are the result of quantum effects. Importantly, such nanoscopic, short-lived quantum effects are consistent with driving some macroscopic physiological processes that biologists have measured in living cells and organisms. Research suggests that quantum effects influence biological functions, including regulating enzyme activity, sensing magnetic fields, cell metabolism and electron transport in biomolecules.
How to study quantum biology
The tantalizing possibility that subtle quantum effects can tweak biological processes presents both an exciting frontier and a challenge to scientists. Studying quantum mechanical effects in biology requires tools that can measure the short time scales, small length scales and subtle differences in quantum states that give rise to physiological changes – all integrated within a traditional wet lab environment.
In my work, I build instruments to study and control the quantum properties of small things like electrons. In the same way that electrons have mass and charge, they also have a quantum property called spin. Spin defines how the electrons interact with a magnetic field, in the same way that charge defines how electrons interact with an electric field. The quantum experiments I have been building since graduate school, and now in my own lab, aim to apply tailored magnetic fields to change the spins of particular electrons.
Research has demonstrated that many physiological processes are influenced by weak magnetic fields. These processes include stem cell development and maturation, cell proliferation rates, genetic material repair and countless others. These physiological responses to magnetic fields are consistent with chemical reactions that depend on the spin of particular electrons within molecules. Applying a weak magnetic field to change electron spins can thus effectively control a chemical reaction’s final products, with important physiological consequences.
Currently, a lack of understanding of how such processes work at the nanoscale level prevents researchers from determining exactly what strength and frequency of magnetic fields cause specific chemical reactions in cells. Current cellphone, wearable and miniaturization technologies are already sufficient to produce tailored, weak magnetic fields that change physiology, both for good and for bad. The missing piece of the puzzle is, hence, a “deterministic codebook” of how to map quantum causes to physiological outcomes.
In the future, fine-tuning nature’s quantum properties could enable researchers to develop therapeutic devices that are noninvasive, remotely controlled and accessible with a mobile phone. Electromagnetic treatments could potentially be used to prevent and treat disease, such as brain tumors, as well as in biomanufacturing, such as increasing lab-grown meat production.
A whole new way of doing science
Quantum biology is one of the most interdisciplinary fields to ever emerge. How do you build community and train scientists to work in this area?
Since the pandemic, my lab at the University of California, Los Angeles and the University of Surrey’s Quantum Biology Doctoral Training Centre have organized Big Quantum Biology meetings to provide an informal weekly forum for researchers to meet and share their expertise in fields like mainstream quantum physics, biophysics, medicine, chemistry and biology.
Research with potentially transformative implications for biology, medicine and the physical sciences will require working within an equally transformative model of collaboration. Working in one unified lab would allow scientists from disciplines that take very different approaches to research to conduct experiments that meet the breadth of quantum biology from the quantum to the molecular, the cellular and the organismal.
The existence of quantum biology as a discipline implies that traditional understanding of life processes is incomplete. Further research will lead to new insights into the age-old question of what life is, how it can be controlled and how to learn with nature to build better quantum technologies.
This article is republished from The Conversation, a nonprofit, independent news organization bringing you facts and trustworthy analysis to help you make sense of our complex world.Like this article? Subscribe to our weekly newsletter.
It was written by: Clarice D. Aiello, University of California, Los Angeles.
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On the general theme of Quantum Physics, here is an article about research that explores a facet of Quantum Physics that is on the speculative side. I am hoping it will be interesting to NewMars members, and perhaps thought inspiring...
https://www.msn.com/en-us/news/technolo … 7602&ei=30
Present-day engines operate based on one of two principles. Power-heat engines, which include all internal combustion engines, steam engines, and rocket engines, convert heat into power. During a controlled explosion in a combustion chamber, energy is released in the form of heat and pressure, which moves a piston that applies a force. Multiple pistons moving at different times generate a rotary motion.
Electric drives rely on the interaction between electric and magnetic fields. By moving an electric field, a counter-pole is moved and exerts a force. In most use cases, this is an electric rotating field that stimulates an axis to rotate.
Now, a whole new type of engine could be entering the game. A group of researchers at the Technical University of Kaiserslautern-Landau is developing a drive based on an as-yet-unused principle, quantum mechanics, as reported by the science magazine spektrum.de. This would use neither electricity nor fuels.
Quantum states as energy suppliers
The scientific team, led by Jennifer Koch, uses the properties of elementary particles for its concept. These belong either to the group of bosons or to the fermions, which form matter. Fermions include electrons and quarks, the basic building blocks of atoms. These tend to repel each other, as they cannot occupy the same quantum state. This effect is known as the Pauli Principle and is the reason for the shell structure of atoms.
In contrast to these are the bosons, the particles that generate and transmit force. Electromagnetic forces are conveyed by photons, while gluons convey strong nuclear force, such as is responsible for the cohesion within an atomic nucleus. Unlike fermions, bosons accumulate together and all take on the lowest energy state.
The effect that physicist Koch and her colleagues are utilizing is as follows: When two fermions are connected, such as by a cleverly applied magnetic field, the particle duo behaves like a boson. In practice, the scientists cool lithium atoms, which are by definition fermions, to almost 0 Kelvin (minus 523.67 degrees Fahrenheit). Due to the Pauli Principle, only one atom occupies the lowest energy state. Additional atoms must occupy a state in which they contain more energy. The researchers then couple these fermions together, and the resulting pairs all fall to the lowest energy level, since they behave like bosons. This effect releases energy that could be used for a possible quantum motor.
Quantum motor is still science fiction
In a laboratory environment, the researchers have already generated this effect, thus proving its function. The cycle process developed has an efficiency of 25 percent. That might sound low at first, but a combustion process with diesel fuel has an efficiency of only 20 percent. The quantum motor is therefore already showing immense potential in its earliest test phase. However, the world will likely have to wait several more years before it can be applied to a product.
This article was published in cooperation with EFAHRER.com.
NewMars readers will note the low value given for the efficiency of diesel motors....
I asked Google for a range of efficiency of diesel motors, and it came back with much higher values:
55-60%
Theoretical system efficiencies for diesel engines range from 55-60%. For reference, the best power stations run at 50-55% efficiency and fuel cells are more than 50% efficient, so diesel engines can be incredibly efficient.
www.fawde.com › news › diesel-engines-most-fuel-efficient
Which diesel engines most fuel efficient? | FAWDE
The Wikipedia article on diesel engines does report that in the earliest versions, efficiency was as low as 16.6%. Improvements made since then have allowed much higher performance.
The Quantum "motor" described in the article apparently requires near-Absolute-Zero conditions, so it is difficult (for me at least) to imagine a large scale application.
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The Carnot "engine" is a classical thermodynamics notion that has nothing to do with molecules, atoms, or quantum anything. What it tells you is what an upper bound is, on the efficiency of any heat engine, which is operating on some sort of thermodynamic cycle between two temperatures. It tells you that based solely on those two temperatures. One is the driving source temperature from which your energy comes, the other is the sink temperature to which you send your waste heat.
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"There is nothing as expensive as a dead crew, especially one dead from a bad management decision"
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Here is an update on developments at the quantum scale:
https://interestingengineering.com/scie … 20.03.24_3
Researchers have turned to quantum dots to clean water pollutants.
Chemical waste, such as dyes and pesticides, is becoming an increasingly serious problem, frequently ending up in water bodies.
Removing pesky chemical waste particles may prove difficult with current methods, which is where the concept of using quantum dots comes in.
The enigmatic laws of quantum physics govern quantum dots.
SEE ALSO
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Here is another update on research at the quantum scale.... researches appear to have found a way to tease atoms to within 50 nanometers of each other, using a set of two different laser "tweezers"...
https://www.yahoo.com/tech/atoms-squish … 24933.html
Live Science
Atoms squished closer together than ever before, revealing seemingly impossible quantum effects
Victoria Atkinson
Tue, May 14, 2024 at 1:21 PM EDT·5 min read
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In other topics, there has been discussion in May of 2024, about various states of hydrogen beyond the familiar gas and liquid states.
This post is about the quantum forces at work between hydrogen molecules, that dictate the low density of the liquid state.
Understanding the Density of Liquid Hydrogen
By any chance, do you have any insight into the quantum mechanical principles that govern the density of liquid hydrogen? Liquid hydrogen has a low density, and I assume this must be due to repulsion of one molecule next to another one. I assume that even at low temperatures where hydrogen is liquid, there must be movement of each molecule next to the others, and that electric repulsion of the electron shells must account for the low density of the material.
Quantum Mechanical Principles and Molecular Interactions
Intermolecular Forces in Liquid Hydrogen
Van der Waals Forces: The primary forces between hydrogen molecules in the liquid state are Van der Waals forces. These are weak intermolecular forces arising from transient dipoles created when electron clouds momentarily become asymmetrical.
Dispersion Forces: Also known as London dispersion forces, these are a type of Van der Waals force that result from correlations in the fluctuating polarizations of nearby particles. For hydrogen, which is nonpolar, dispersion forces are the dominant intermolecular attraction.
Quantum Mechanical Effects
Electron Shell Repulsion: Hydrogen molecules experience repulsion when their electron clouds come close to one another. This repulsion, due to the Pauli exclusion principle, prevents the electron clouds from overlapping significantly, maintaining a minimum distance between molecules.
Zero-Point Energy: Even at absolute zero, hydrogen molecules possess zero-point energy due to quantum mechanical constraints. This energy contributes to the movement of molecules, preventing them from being perfectly stationary and influencing the density of the liquid.
Density of Liquid Hydrogen
Low Density Explained
Molecular Size and Repulsion: Hydrogen molecules (H\(_2\)) are small and light, but the repulsion between their electron clouds keeps them from packing closely together. This results in a relatively low density.
Weak Intermolecular Forces: The weak Van der Waals forces in liquid hydrogen mean that the molecules are not held tightly together. This allows for more free movement and results in a lower density compared to substances with stronger intermolecular forces.
Temperature and Movement
Thermal Motion: At the temperatures where hydrogen is liquid (around 20.28 K at 1 atmosphere), the thermal energy causes significant molecular motion. Even though the motion is less than in the gaseous state, it is still enough to prevent close packing.
Quantum Effects at Low Temperatures: Quantum effects become more pronounced at low temperatures. The wave nature of particles means that hydrogen molecules exhibit quantum delocalization, further preventing them from being as densely packed as classical particles would be.
Summary of Contributing Factors
Weak Intermolecular Attractions: Hydrogen molecules are held together by weak Van der Waals forces, which are insufficient to pack the molecules densely.
Electron Cloud Repulsion: The electron clouds around hydrogen molecules repel each other, preventing close approach.
Quantum Zero-Point Motion: Even at low temperatures, quantum zero-point motion contributes to the spacing between molecules.
Thermal Motion: The thermal energy at liquid hydrogen temperatures adds to the molecular movement, reducing density.
Comparison with Solid Hydrogen
In solid hydrogen, the molecules are more closely packed because the thermal motion is further reduced, and the molecules arrange themselves in a crystalline structure, which allows for a higher density than in the liquid state. However, even in solid form, the density is relatively low compared to many other substances because of the weak intermolecular forces and the quantum mechanical effects that keep the molecules from being too tightly packed.
Conclusion
The low density of liquid hydrogen is a result of the interplay between weak intermolecular forces, electron cloud repulsion, quantum zero-point motion, and thermal motion. These factors prevent the hydrogen molecules from packing closely together, resulting in a low-density liquid. Understanding these principles highlights the unique behaviors of hydrogen and the importance of quantum mechanics in dictating the properties of matter even at macroscopic scales.
The report was prepared by ChatGPT4o as guided by tahanson43206.
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This post is about the Bose-Einstein state. It reveals that Protium cannot form such a state, but both Deuterium and Tritium can. Of the two, Deuterium is far more abundant. The report shows the low temperature required to achieve such a state.
Bose-Einstein Condensate and Hydrogen
There is a state of matter attributed to research/speculation by scientists Einstein and Bose. I understand that the Bose-Einstein state has been achieved in laboratory settings. My question for you is whether a Bose-Einstein state might exist for hydrogen? My understanding is that in this state, a collection of atoms are in phase with each other. I have no idea if such a state might allow hydrogen molecules to pack together more densely than in the liquid state, but I'm hoping you may have insight into the question.
Bose-Einstein Condensate (BEC) Overview
Definition and Characteristics
Quantum State: In a BEC, particles occupy the lowest quantum state, behaving as a single quantum entity. This means they are in phase with each other and can exhibit coherent properties similar to a single giant atom.
Bosons: Only bosons can form a BEC because they obey Bose-Einstein statistics. Unlike fermions, bosons do not obey the Pauli exclusion principle, allowing them to occupy the same quantum state.
BEC Formation
Ultra-Low Temperatures: BECs are formed at temperatures close to absolute zero, where thermal energy is minimal, and quantum effects dominate.
Experimental Achievements: The first BEC was created in 1995 using rubidium-87 atoms. Since then, BECs have been achieved with various alkali atoms and other elements.
Hydrogen and Bose-Einstein Condensates
Hydrogen as a Boson
Deuterium and Tritium: Deuterium (a hydrogen isotope with one proton and one neutron) and tritium (one proton and two neutrons) are bosons due to their integer nuclear spins. Protium (the most common hydrogen isotope with just one proton) is not a boson.
Molecular Hydrogen (H\(_2\)): Hydrogen molecules (H\(_2\)) are also bosons because they consist of two fermions (protons) whose spins combine to form an integer spin state.
Achieving BEC with Hydrogen
Experimental Challenges: Creating a BEC with hydrogen is challenging due to hydrogen's low mass, which requires extremely low temperatures and sophisticated cooling techniques.
Success with Atomic Hydrogen: In 1998, scientists achieved a BEC with atomic hydrogen. This required cooling the atoms to below 50 microkelvin.
Density of Hydrogen in BEC State
In-Phase Behavior and Density
Quantum Coherence: In a BEC, hydrogen atoms or molecules exhibit coherence, behaving as a single quantum wavefunction. This coherence can potentially affect the packing density.
Reduced Kinetic Energy: At temperatures where BECs form, the kinetic energy of the particles is minimized. This could, in theory, allow them to pack more closely than in the liquid state, where thermal motion still contributes to maintaining distance between molecules.
Comparative Density
Atomic Hydrogen BEC: For atomic hydrogen, the BEC state might allow for denser packing than in the gaseous state, but practical limitations in achieving and maintaining this state make it difficult to compare directly with liquid hydrogen.
Molecular Hydrogen BEC: If molecular hydrogen (H\(_2\)) were to form a BEC, it might pack more densely than liquid hydrogen due to reduced thermal motion and increased coherence. However, achieving and maintaining such a state for molecular hydrogen is even more challenging.
Conclusion
A Bose-Einstein Condensate (BEC) for hydrogen is theoretically possible and has been achieved for atomic hydrogen. In a BEC state, hydrogen atoms or molecules are in phase with each other, which could potentially allow for denser packing compared to the liquid state. However, the practical challenges of achieving and maintaining a BEC, particularly for molecular hydrogen, mean that such a state is not easily comparable to more familiar states of matter like liquid hydrogen.
Exploring BECs of hydrogen further could provide valuable insights into quantum mechanics and matter under extreme conditions, potentially opening new avenues for scientific and technological advancements. If you have any more questions or need further details, feel free to ask!
Prepared by ChatGPT4o as guided by tahanson43206.
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Here is a follow up regarding the apparent ambiguity in earlier posts. It had been asserted that Protium could not form a BEC, but it was reported that in 1998 scientists had created a BEC with atomic hydrogen. This post is a report on clarification of that ambiguity.
Bose-Einstein Condensate and Hydrogen
There is a state of matter attributed to research/speculation by scientists Einstein and Bose. I understand that the Bose-Einstein state has been achieved in laboratory settings. My question for you is whether a Bose-Einstein state might exist for hydrogen? My understanding is that in this state, a collection of atoms are in phase with each other. I have no idea if such a state might allow hydrogen molecules to pack together more densely than in the liquid state, but I'm hoping you may have insight into the question.
Bose-Einstein Condensate (BEC) Overview
Definition and Characteristics
Quantum State: In a BEC, particles occupy the lowest quantum state, behaving as a single quantum entity. This means they are in phase with each other and can exhibit coherent properties similar to a single giant atom.
Bosons: Only bosons can form a BEC because they obey Bose-Einstein statistics. Unlike fermions, bosons do not obey the Pauli exclusion principle, allowing them to occupy the same quantum state.
BEC Formation
Ultra-Low Temperatures: BECs are formed at temperatures close to absolute zero, where thermal energy is minimal, and quantum effects dominate.
Experimental Achievements: The first BEC was created in 1995 using rubidium-87 atoms. Since then, BECs have been achieved with various alkali atoms and other elements.
Hydrogen and Bose-Einstein Condensates
Hydrogen as a Boson
Deuterium and Tritium: Deuterium (a hydrogen isotope with one proton and one neutron) and tritium (one proton and two neutrons) are bosons due to their integer nuclear spins. Protium (the most common hydrogen isotope with just one proton) is a fermion by itself.
Molecular Hydrogen (H\(_2\)): Hydrogen molecules (H\(_2\)) are also bosons because they consist of two fermions (protons) whose spins combine to form an integer spin state.
Achieving BEC with Hydrogen
Experimental Challenges: Creating a BEC with hydrogen is challenging due to hydrogen's low mass, which requires extremely low temperatures and sophisticated cooling techniques.
Success with Atomic Hydrogen: In 1998, scientists achieved a BEC with atomic hydrogen. Although individual hydrogen atoms are fermions, advanced techniques such as laser cooling, evaporative cooling, and magnetic trapping allowed them to reach the required conditions for BEC formation.
Density of Hydrogen in BEC State
In-Phase Behavior and Density
Quantum Coherence: In a BEC, hydrogen atoms or molecules exhibit coherence, behaving as a single quantum wavefunction. This coherence can potentially affect the packing density.
Reduced Kinetic Energy: At temperatures where BECs form, the kinetic energy of the particles is minimized. This could, in theory, allow them to pack more closely than in the liquid state, where thermal motion still contributes to maintaining distance between molecules.
Comparative Density
Atomic Hydrogen BEC: For atomic hydrogen, the BEC state might allow for denser packing than in the gaseous state, but practical limitations in achieving and maintaining this state make it difficult to compare directly with liquid hydrogen.
Molecular Hydrogen BEC: If molecular hydrogen (H\(_2\)) were to form a BEC, it might pack more densely than liquid hydrogen due to reduced thermal motion and increased coherence. However, achieving and maintaining such a state for molecular hydrogen is even more challenging.
Conclusion
A Bose-Einstein Condensate (BEC) for hydrogen is theoretically possible and has been achieved for atomic hydrogen. In a BEC state, hydrogen atoms or molecules are in phase with each other, which could potentially allow for denser packing compared to the liquid state. However, the practical challenges of achieving and maintaining a BEC, particularly for molecular hydrogen, mean that such a state is not easily comparable to more familiar states of matter like liquid hydrogen.
Exploring BECs of hydrogen further could provide valuable insights into quantum mechanics and matter under extreme conditions, potentially opening new avenues for scientific and technological advancements. If you have any more questions or need further details, feel free to ask!
This report was prepared by ChatGPT4o as guided by tahanson43206.
Update:
Reference to 1998 Work on Atomic Hydrogen BEC
For those interested in the significant 1998 achievement of creating a Bose-Einstein Condensate (BEC) with atomic hydrogen, here is a key reference:
Title: "Observation of Bose-Einstein Condensation in a Dilute Atomic Vapor"
Authors: D. G. Fried, T. C. Killian, L. Willmann, D. Landhuis, S. C. Moss, D. Kleppner, and T. J. Greytak
Journal: Physical Review Letters, Volume 81, 1998, Pages 3811-3814
Abstract: This paper reports the successful observation of Bose-Einstein condensation in atomic hydrogen. Using advanced cooling techniques and magnetic trapping, the team achieved the necessary conditions for atomic hydrogen to form a BEC. This work was significant because it demonstrated the feasibility of creating a BEC with a simple atom like hydrogen, which had previously been challenging due to hydrogen's low mass and high thermal velocity.
This groundbreaking research opens up new avenues for exploring quantum mechanics and matter under extreme conditions. For more details, you can refer to the original publication in Physical Review Letters.
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The qubit a fundemental of both quantum mechanics and quantum computing, applications like Quantum sensing, Quantum computing and Quantum communication use different implementations of qubits, the quantum version of classic binary physically realized with a two-state device, the qubit two-state or two-level quantum-mechanical system, one of the simplest quantum systems displaying the peculiarity of quantum mechanics.
The quantum Carnot-like heat engine: The level degenerate case
https://www.semanticscholar.org/paper/T … 36b03f380e
Programmable Heisenberg interactions between Floquet qubits
https://www.nature.com/articles/s41567-023-02326-7
Attaining Carnot efficiency with quantum and nanoscale heat engines
https://www.nature.com/articles/s41534-021-00366-6
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The article below reports on research into heat flow at the nanoscale. It appears that the "law" of heat transfer in solids depends upon uniform material in the solid, and that the rule breaks down at the nanoscale. The research probes the question of how tiny defects in certain materials may influence heat transfer.
The rules of thermal engagement are being rewritten by an unexpected scientific anomaly.
© Tawanna08 - Getty Images
For 200 years, Fourier’s law has been the go-to explanation for how heat diffuses through solid materials (at least on macro scales).
However, a new study by scientists at the University of Massachusetts Amherst has detected heat behavior in translucent polymers and inorganic glass that this time-tested law can’t explain.
Fleshing out a deeper understanding of how heat works could help engineers craft electronic components that are even more heat-resistant.
In 1822, French mathematician and physicist Jean-Baptise Joseph Fourier published the treatise Théorie analytique de la chaleur, or The Analytical Theory of Heat. In this treatise, Fourier describes a law of physics that would eventually become his namesake. This law of heat conduction, known today as Fourier’s Law, mathematically described the rate at which heat transfers through a solid material. That hot cup of coffee slowly warming your hand? That’s Fourier’s law in action.
In the 200 years since, Fourier’s law has held up pretty well. But things changed during the dawn of nanotechnology, because the law breaks down when predicting thermal performance across nanodevices. And a new study, published in the Proceedings of the National Academy of Sciences, argues that these exceptions aren’t limited to the world of the miniscule.
By analyzing the heat performance of translucent polymers and inorganic glasses, scientists from the University of Massachusetts Amherst were able to detect anomalies that could not be explained with Fourier’s Law.
“This research began with a simple question,” UMass Amherst’s Steve Granick, the senior author on the paper, said in a press statement. “What if heat could be transmitted by another pathway, not just the one that people had assumed?”
Although textbooks have, for 200 years, explained heat transfer through a process known as diffusion, Granick explains that his team needed to get creative and “put the textbook aside for a moment.” The researchers’ idea was that translucent polymers and inorganic glasses would diffuse heat as normal, but their translucence would also allow electromagnetic thermal energy to radiate through the material.
With samples situated in a vacuum chamber, the scientists eliminated the air necessary for the convective distribution of heat. Then, as the best experiments always do, the research team turned on some lasers. In one sample, they pulsed heat in a small area while another sample was warmed on one side and kept cold on the other. To track heat spread across the samples, the team relied on incredibly precise infrared cameras. Once the data was collected, they confirmed their suspicions—Fourier’s law had failed on a macro scale.
Granick and his team came to the conclusion that these translucent materials radiate energy internally. But crucially, this heat interacts with structure imperfections, which the researchers say creates “secondary heat sources.”
“It’s not that Fourier’s Law is wrong,” Granick said in a press statement. “Just that it doesn’t explain everything we see when it comes to heat transmission.”
Understanding the behavior of heat is vitally important for creating computing devices, where heat is the ultimate enemy.
By poking holes in this 200-year-old law, these scientists hope to gain a deeper understanding of heat behavior—something you won’t find in your usual scientific textbook.Popular Mechanics
I'm wondering if this insight might (?possibly?) allow for design of better heat shields...
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The article at the link below reports on research into a (possible) quantum state for gravity.
There is a case to be made that all of the Real Universe is quanticized. however, gravity has resisted confirmation.
This article reviews the history, and lays out a possible pathway to detect a single graviton.
The would would require a major investment, and a career dedication measured in decades.
https://www.quantamagazine.org/it-might … wtab-en-us
A key finding (if a theory can be said to be "finding" anything) is that gravitons are far more likely to be travelling in massive waves such as those produced by collapsing black holes, than emanating from puny sources such as our Sun.
Thus, the proposed experiment would tag onto the LIGO detectors. If a LIGO event occurs, then the researches would look at their graviton detector to see if it caught one.
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