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#quantummechanics — Public Fediverse posts

Live and recent posts from across the Fediverse tagged #quantummechanics, aggregated by home.social.

  1. Physicists Find Useful Energy Hiding in Quantum “Waste Heat”

    An atom in a cavity between two mirrors (left) acts as a heat engine in a driven-dissipative quantum…
    #NewsBeep #News #Physics #AU #Australia #QuantumMechanics #QuantumPhysics #quantumtechnology #Science #Thermodynamics #UniversityofBasel
    newsbeep.com/au/885958/

  2. Meet Rachel Chen, the 18-year-old Los Angeles student who expanded a 1997 quantum-math idea to describe entire particle systems with simple diagrams; she won $100,000

    Rachel Chen, 18, won $100,000 for her inno…
    #NewsBeep #News #Physics #AU #Australia #LosAngelesstudent #quantummathematics #QuantumMechanics #quantumparticles #QuantumPhysics #RachelChen #RegeneronScienceTalentSearch2026 #Science #spinrepresentation #Temperley-Liebalgebra #Temperley-Liebdiagrams
    newsbeep.com/au/885772/

  3. Semiconductor Physics by P.S. Kireev

    This textbook originates from lectures delivered by the author to students of the Semiconductor Materials and Devices Faculty at the Moscow Institute of Steel and Alloys. It assumes prior knowledge of subjects like Crystallography and Quantum Mechanics, allowing the material to focus exclusively on semiconductor physics without revisiting crystal lattice structures or atomic bonding. Leveraging students’ understanding of quantum mechanics, the textbook employs rigorous methods to address topics such as energy band structures and charge carrier transitions, including their interactions with lattice defects, phonons, and photons. Detailed intermediate calculations and experimental data further enhance comprehension.

    While the material is presented at a high level, it remains accessible, supported by clear derivations and illustrations. Group theory methods are introduced to simplify problem-solving but are confined to an appendix, as this subject is typically not part of technical college curricula. The book deliberately avoids covering the operation of specific semiconductor devices, treating Semiconductor Physics as a distinct discipline with a focus on fundamental principles.

    Translated from the Russian by Mark Samokhvalov

    All credits to the original uploaders, this is an optimised pdf.

    You can get the book here and here

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    CONTENTS
    Preface 9

    Chapter I. Introduction. Electron Theory of Conductivity 11

    Electron Theory of Conductivity. Ohm’s Law 11
    Mean-Free Time and Free-Path Distribution Functions 16
    Electron Distribution Function. Mean Values of Physical Quantities 20
    Semiconductors. The Classification of Materials According to Their Conductivity 31
    Semiconductor Conductivity Models. The Concept of a Hole 35
    Intrinsic and Extrinsic Conductivities 39
    Chapter II. The Fundamentals of the Band Theory of Semiconductors 42
    7. The Schrödinger Equation for the Crystal 42
    8. The Adiabatic Approximation 45
    9. Single Electron Approximation 50
    10. Periodic Field of the Crystal Lattice. Translational Operator 54
    11. Quasimomentum 59
    12. The Effective Mass of the Electron 64
    13. Relation Between Velocity and Quasimomentum 70
    14. Acceleration Operator 73
    15. Brillouin Zones 80
    16. Normalising Inside a Potential Box and the Discrete Nature of Quasimomentum 85
    17. Theory of the Quasifree Electron 90
    18. Theory of the Quasibound Electron 105
    19. Effective Mass Method. Influence of External Fields on Energy Spectrum of a Crystal 119
    20. Localised States 125
    21. Elementary Theory of Impurity States 130
    22. Surface States 138
    23. Quantisation of Electron Energy in a Magnetic Field. Landau Levels 141
    24. Pauli Principle. Concept of Metal, Semiconductor, and Dielectric 146
    25. Main Features of the Hole 153
    26. Band Structure of Some Semiconductors. Calculation Methods 158
    27. Quasiparticle Concept 175

    Chapter III. Electron and Hole Statistics in Semiconductors 180
    28. Density of States 180
    29. Electron and Hole Concentrations 189
    30. Electric Neutrality Equation 197
    31. Intrinsic Semiconductor 200
    32. Extrinsic Semiconductor. Impurity of One Type 205
    33. Semiconductor Doped with Both Acceptor and Donor Impurities 215
    34. Degenerate Semiconductor 221
    35. Density of States in a Magnetic Field 225

    Chapter IV. Kinetic Phenomena in Semiconductors 234
    36. Boltzmann’s Kinetic Equation 234
    37. Relaxation Time 241
    38. Electric Current Density and Energy Flux Density 249
    39. Kinetic Coefficients 253
    40. Conductivity of Semiconductors 261
    41. Galvanomagnetic Effects 270
    42. Hall Effect in Extrinsic Conductivity Range 280
    43. Hall Effect in a Substance with Several Types of Charge Carriers 288
    44. Magnetic Field Dependence of Hall Coefficient 294
    45. Magnetoresistive Effect 302
    46. Heat Conductivity of Semiconductors 311
    47. Thermoelectric Phenomena 318
    48. Thermomagnetic Phenomena 334
    49. General Analysis of Kinetic Phenomena 338
    50. On Kinetic Phenomena in Semiconductors with Tensor Effective Masses 348
    51. Tensorsensitive Effect. Tensorsensitivity 352
    52. Piezoresistive Effect. Piezoresistance Coefficients 359

    Chapter V. The Theory of Charge Carrier Scattering 369
    53. Effective Scattering Cross Section 369
    54. Relationship Between Relaxation Time and Effective Cross Section 378
    55. Elements of Quantum Transition Theory 383
    56. Impurity Ion Scattering 390
    57. Scattering by Neutral Impurity Atoms 398
    58. Lattice Vibrations. Normal Coordinates, Phonons 401
    59. Acoustical and Optical Lattice Vibrations 409
    60. Lattice Specific Heat. Phonon Statistics 422
    61. Scattering by Thermal Lattice Vibrations. Method of Deformation Potential 432
    62. Temperature Dependence of Charge Carrier Mobility 441
    63. Dependence of Relaxation Time on External Fields. Deviations from Ohm’s Law 452

    Chapter VI. Charge Carrier Recombination 461
    64. Continuity Equation. Lifetime 461
    65. Recombination Mechanism. Linear Recombination 472
    66. Diffusion and Drift of Nonequilibrium Charge Carriers 484
    67. Surface Recombination 492

    Chapter VII. Contact Phenomena in Semiconductors 497
    68. Debye Length 497
    69. Work Function 510
    70. Contact Potential Difference. Metal-Metal Contact 515
    71. Metal-Semiconductor Contact 519
    72. Inhomogeneous Semiconductor, p-n Junction 525

    Chapter VIII. Optical and Photoelectrical Phenomena in Semiconductors 532
    73. Light-Absorption Spectrum 532
    74. Light Absorption by Free Charge Carriers 536
    75. Cyclotron Resonance 546
    76. Intrinsic Light Absorption 555
    77. Absorption of Light by the Lattice 573
    78. Light Absorption by Electrons in Localised States 579
    79. Influence of the Ambient on Absorption Spectrum 586
    80. Photoresistive Effect 590
    81. Dember Effect. Photovoltaic Effect 599
    82. Photomagnetoelectric Effect 608
    83. Faraday Effect 613
    84. Spin-Orbital Splitting of Energy Bands 623

    Appendix. Introduction to the Theory of Groups 633

    Space Transformations 633
    Group of Symmetry Transformations. Properties of Group Elements 639
    Relation Between Groups 643
    Representation of Groups 646
    The Properties of Irreducible Representations 649
    The Basis of a Representation 652
    Direct Product of Representations 655
    Point Groups 659
    Translational Groups. Brillouin Zones 665
    The Wave Vector Group 671
    Schrödinger Equation 680
    Twin Groups. Time Inversion 684
    Recommended Literature 694

     

    #physics #quantumMechanics #semiconductors #sovietLiterature
  4. Someone has solved the mystery of Sonoluminescence.

    He has also created the Quantum Gravity formalism, the unification of the General Relativity (GR) and the Quantum Mechanics (QM).

    More details on zenodo.org/records/21970203

    #Sonoluminescence #Physics #Mathematics #GeneralRelativity #QuantumMechanics #QuantumGravity

  5. Can #Science prove the absence of #God? 🧠🌌

    If #neuroscientists can use an #MRI to pinpoint the exact moment when we sense something “divine”—is #God then just a chemical reaction in the temporal lobe? Or have we simply discovered the physical antenna for the #immaterial?

    🎧 Listen now & join the discussion!

    open.spotify.com/episode/78cv2

    #Philosophy #Science #Physics #QuantumMechanics #Neurotheology #Epistemology #Podcast #ThoughtExperiment #philosophies_de

  6. How to image a #wavefunction?

    Fundamental particles, such as electrons, cannot be pinned down to one single location. Instead, a particle is described by its “wavefunction” – but imaging the wavefunction is a major challenge. Researchers @ our Uni managed to image the 3D wavefunction of a nanometer-sized organic molecule by combining state-of-the-art photoelectron spectroscopy with powerful mathematical algorithms: uni-goettingen.de/en/3240.html

    Research in #NatureCommunications: doi.org/10.1038/s41467-026-743

    #QuantumMechanics #MolecularOrbitals #UltrafastDynamics

  7. АНТРОПОЛОГИЯ, ANTHROPOLOGY, АНТРОПОЛОГІЯ
    #АНТРОПОЛОГИЯ, #ANTHROPOLOGY, #АНТРОПОЛОГІЯ
    t.me/scilib_yura15cbx/542

    Thermodynamics, statistical physics
    Термодинамика, статистическая физика
    Термодинаміка, статистична фізика
    #Thermodynamics, #statistical physics
    #Термодинамика, #статистическаяфизика
    #Термодинаміка, #статистична
    фізика
    t.me/scilib_yura15cbx/541

    PQm Quantum mechanics
    Квантовая механика
    Квантова механіка
    #Quantum mechanics
    #Квантоваямеханика
    #Квантова
    механіка
    t.me/scilib_yura15cbx/540

    PQft Quantum field theory
    Квантовая теория поля
    Квантова теорія поля
    #Quantum field theory
    t.me/scilib_yura15cbx/539

    Фазовые переходы
    Phase_transitions, Фазовіпереходи
    #Фазовые переходы
    #Phase transitions, #Фазові
    переходи
    t.me/scilib_yura15cbx/538

    Пиротехника, Піротехніка, Pyrotechnics
    #Пиротехника, #Піротехніка, #Pyrotechnics
    t.me/scilib_yura15cbx/537

    Астрономия, Астрономія, Astronomy
    #Астрономия, #Астрономія, #Astronomy
    t.me/scilib_yura15cbx/536

    PPop Popular-level
    Популярная физика
    Популярна Фізика
    t.me/scilib_yura15cbx/535

    PG General courses
    Общие курсы
    Загальні курси
    t.me/scilib_yura15cbx/534

    PPl Plasma Плазма
    Физика плазмы
    #Plasma #Плазма
    #Физика плазмы
    t.me/scilib_yura15cbx/533

    PPh Philosophy of Physics
    Философия физики,
    Філософія фізики
    t.me/scilib_yura15cbx/532

    POs Oscillations and waves
    Колебания и волны
    Коливання і хвилі
    t.me/scilib_yura15cbx/531

    PNu Nuclear Physics
    Ядерна фізика
    Ядерная физика
    #Nuclear Physics
    #Ядернафізика
    #Ядерная
    физика
    t.me/scilib_yura15cbx/530

    PNc Nonlinear chaos
    Нелинейный хаос
    Нелінійний хаос
    #Nonlinear chaos
    #Нелинейныйхаос
    #Нелінійний
    хаос
    t.me/scilib_yura15cbx/529

    PM Atomic Molecular and Optical Physics
    Атомна молекулярна та оптична Фізика
    Атомная молекулярная и оптическая физика
    t.me/scilib_yura15cbx/528

    PGrc Cosmology
    Космология
    Космологія
    #Cosmology
    #Космология
    #Космологія
    t.me/scilib_yura15cbx/527

    PGr Gravitation
    Гравитация
    Гравітація
    #Gravitation
    #Гравитация
    #Гравітація
    t.me/scilib_yura15cbx/526

    PGe Encyclopaediae physics
    Енциклопедія
    Энциклопедии
    t.me/scilib_yura15cbx/525

    PE Electromagnetism
    Електромагнетизм
    Электромагнетизм
    #Electromagnetism
    #Електромагнетизм
    #Электромагнетизм
    t.me/scilib_yura15cbx/523

    PD Dynamical systems
    Динамические системы
    Динамічна система
    t.me/scilib_yura15cbx/522

    PCh Chemical physics
    Хімічна фізика
    Химическая физика
    #Chemical physics
    #Хімічнафізика
    #Химическая
    физика
    t.me/scilib_yura15cbx/521

    PCtm Theoretical mechanics
    Теоретическая механика
    Теоретична механіка
    t.me/scilib_yura15cbx/520

    PCstr Special relativity
    Спеціальна теорія відносності
    Специальная теория относительности
    t.me/scilib_yura15cbx/519

    PCft Classical fields
    Классические поля, классическая теория поля, класична теорія поля
    t.me/scilib_yura15cbx/518

  8. Scientific Explanations For Deja Vu And The Paranormal

    Most of us at some point in our lives have experienced Deja vu, that is we feel as though an experience we’re having or seeing has happened before. Most of us have also had the experience of seeing something out of the corner of our eye, or the sensation of having chills for no known reason. Some people also report that they’ve seen ghosts, spirits or aliens. Some of these phenomena such as ghosts or spirits are quite often associated with people who have passed away, sometimes in […]

    johnbronze.wordpress.com/2026/

  9. Theory Of Stellar Spectra by V.V. Sobolev

    The only source of our information on stars is their radiation. From stellar spectra we judge the structure of stellar atmospheres, their chemical composition, and physical processes taking place there. Spectrograms are interpreted on the basis of the theory of stellar spectra, wherein lies its enormous value for astrophysics. Until recently astronomers could observe stellar radiation only in a very small range of frequencies making up the visible region of the spectrum. However, about 20 years ago radio astronomy came into being which permits investigating the radiation of celestial bodies in a completely different spectral region.

    Quite recently, in connection with the launching of satellites and rockets, there arose the theoretical possibility of obtaining stellar spectra in any frequency range. So far, highly useful spectrograms of stars and the sun have been obtained in the so-called rocket ultraviolet. It is obvious that this broadening of observational data will even further increase the significance of the theory of stellar spectra. At the same time it is necessary to improve and extend this theory.

    The surface layers of stars, out of which their spectra arise, represent
    strongly ionized gases, i.e., plasma. Plasma studies are also being carried out in physics laboratories, having increased in intensity of late. Methods used by physicists in studying plasmas are in many respects similar to methods used by astrophysicists in studying stellar atmospheres. Therefore, the theory of stellar spectra is of interest not only to astrophysicists but also to physicists.

    An excellent example of the broad interest in the theory of stellar spectra is the summer seminary on problems of this theory, organized by the
    Astronomical Council of the Academy of Sciences of the USSR and the Leningrad University and held in Leningrad in June 1964* About 150 young astrophysicists and physicists of the Soviet Union participated in the sessions. This book was written on the basis of the lectures given at that time.
    The first part of the book examines atomic processes associated with the
    formation of spectra, with special emphasis on calculation of the energy levels of the atom and the probability of transitions between these levels. The second part deals with the theory of radiation transfer, which forms an important aspect of the theory of stellar spectra. The next two parts discuss the most essential problems in the formation of spectra of different types of stars and nebulae. The last part, devoted to ultraviolet spectra of celestial bodies, mainly gives a review of observational data and their qualitative interpretation (since, as yet, no quantitative theory of these spectra has been established).
    The diversity of the problems of the modern theory of stellar spectra makes it impossible to present them with sufficient completeness in a single monograph.
    The authors of this book have endeavored to acquaint the reader with the most important of these problems.

     

    You can get the book here and here

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    Preface …………………………………………… iii
    PART I. PHYSICAL PROCESSES CONNECTED WITH THE FORMATION OF SPECTRA ………… 1
    Plasma Spectroscopy (S.E. Frish) …………………….. 1
    Calculations of Atomic Energy Levels (A.P. Yutsis and Ya.I. Vizbarayte) …………… 23
    Theory of Atomic Transitions (G.F. Drukarev) ……….. 35

    PART II. THEORY OF RADIATIVE TRANSFER ……………………… 64
    Certain Nonlinear Problems of the Theory of Radiative Transfer (V.A. Ambartsumyan) ……. 64
    Radiative Diffusion in Gases (V.V. Sobolev) …………. 75
    Determination of the Populations of Excited Levels in an Optically Thick Gas Layer (V.V. Ivanov) ……….. 92
    Nonstationary Radiation Field (I.N. Minin) …………. 116
    Randomized Problem of Diffuse Reflection (R.V. Ambartsumyan) ………… 135

    PART III. SPECTRA OF FIXED STARS ……………………….. 140
    Models of Stellar Atmospheres (V.V. Sobolev) ………. 140
    Continuous Spectra of Hot White Dwarfs (A.K. Kolesov) ……. 147
    Model Atmospheres of Main-Sequence Stars of Class M (V.G. Buslavskiy) …….. 152
    Determination of the Chemical Composition of Stellar Atmospheres (A.A. Boyarchuk) ……….. 160

    PART IV. SPECTRA OF NONSTATIONARY STARS AND INTERSTELLAR MATTER ………… 170
    Spectra of Nonstationary (Variable) Stars (V.G. Gorbatskiy) ……….. 170
    Analysis of the Emission Spectra of Nonstationary Stars (A.A. Boyarchuk) ………… 194
    Spectra of Interstellar Matter (S.A. Kaplan) ………… 203
    Radio Observations of Planetary Nebulae (Yu. N. Pariyskiy) ………. 216

    PART V. SPECTRA OF CELESTIAL BODIES IN THE FAR ULTRAVIOLET REGION ……….. 220
    Spectra of Celestial Bodies in the Far Ultraviolet Region (G.A. Gurzadyan) ………. 220

    #astronomy #astrophysics #physics #quantumMechanics #radiativeTransfer #sovietLiterature #stellarSpectra #stellarStructure
  10. [en] Moore’s Law? When #computer chips can't get smaller (can they?)

    "... in the last 15 years, transistors have gotten close to the point where #quantum mechanics starts to interfere with their function: just a few dozen nanometers in size. They can’t get smaller."

    "... approach familiar to urban planners: build up. On Thursday, #IBM announced it has created a #chip that uses this strategy. The new #architecture, known as a #nanostack, vertically stacks transistors in two layers on a #silicon chip."

    technologyreview.com/2026/06/2

    #transistor #moore #mooreslaw #quantummechanics

  11. 1/n Notes on #UAP Discussions : Many of us never expected UAP to enter into consideration in work on #QuantumGravity because you'd basically be run out of town. Things changed somewhat when weight of evidence came down in favor of there being physically real vehicles involved. It isn't #SciFi anymore.
    Still, many don't understand why
    #QuantumMechanics and #Relativistic #Physics are important here. The concepts are challenging, even for grad students.
    Einstein unified time and space and...

  12. Master Index

    A guided map across physics, biology, engineering, and AI—built around a simple idea

    Persistence is not generated, but permitted.

    Systems don’t fail because they “break.”

    They fail because their boundaries were misclassified.

    Core structure
    state → constraint → resolution → persistence

    From: - Titanic / Vasa / Challenger
    – biological regulation
    – AI hallucination & drift
    – institutional collapse

    Same pattern
    only admissible states persist

    This is the interface.
    Start anywhere. Follow the path that fits.

    #HybridMind42 #BoundaryDynamics #BoundaryArchitecture #BFPF #HQP
    #Admissibility #ConstraintResolution #StateTransition #Persistence
    #ComplexSystems #SystemsThinking #StructuralAnalysis #FailureAnalysis
    #Physics #QuantumMechanics #Relativity #Lindblad #CPTP #Decoherence
    #Biology #Physiology #Adaptation #Homeostasis
    #ArtificialIntelligence #AI #LLM #AIAlignment #AIGovernance
    #InstitutionalFailure #DecisionMaking
    #Emergence #ScientificClarity

    substack.com/@hybridmind42/not

  13. Bouncing on a Wave

    On a vibrating fluid, droplets can bounce and interact in complex ways. Here, researchers demonstrate some of the peculiar dynamics of these wave-guided droplets, showing how they can do things like pair up in waltzes. To keep the droplets from coalescing with one another, they perform their experiments in a pressurized chamber; the higher air pressure makes it harder for the air film between droplets to drain during a collision, making the droplets unable to coalesce. Under these conditions, the authors show that the droplet-wave system has quantum-like statistics. (Video and image credit: J. Clampett et al.)

    #2025gofm #bouncingDroplets #coalescence #droplets #flowVisualization #fluidDynamics #hydrodynamicQuantumAnalogs #physics #pilotWaveHydrodynamics #quantumMechanics #science #vibration
  14. ¨The first reaction to this work is that it is wrong.
    The second is that it is obvious.”
    — Victor Weisskopf

    The Aharonov-Bohm effect is a fascinating story.
    youtu.be/XKSjCOKDtpk

    #Science #Magnetism #QuantumMechanics #FieldTheory

  15. If usefulness isn’t a guide to what’s real, what is?

    Seems like I’ve been writing a lot about quantum mechanics lately. Apparently so have a lot of other people. One thing that keeps coming up is the reality or non-reality of the quantum wave function. Raoni Arroyo and Jonas R. Becker Arenhart argue for non-reality: Quantum mechanics works, but it doesn’t describe reality: Predictive power is not a guide to reality. (Warning: likely paywall.)

    Along similar lines, in an article about what he says are quantum myths, Ethan Siegel argues that superpositions are not fundamental to quantum physics:

    Superpositions are incredibly useful as intermediate calculational steps to determine what your possible outcomes (and their probabilities) will be, but we can never measure them directly.

    Arroyo and Arenhart take a similar line. They argue that it would be more intellectually honest for wave function realists to call their position wave function pragmatism. As they note in the title of their piece, they don’t see predictive success as a guide to reality.

    The question I want to ask these people is, if predictive power, if usefulness, isn’t your guide to what is real, then what is?

    It’s worth thinking about why we care whether something is real or not. Is the sound I’m hearing from outside rain? Is the rain real? To say it is is to say I need to take an umbrella with me when I go outside, or be prepared to get wet. To say it isn’t is to say I can walk outside without worry of getting wet. We get similar considerations when trying to decide if a stock rally is real or illusory, or, from an evolutionary perspective, whether the sound in the bushes is a real predator or just a figment of your imagination. Reality is that which makes a difference, something which there’s a possible cost to ignoring.

    Admittedly, this is a strange point to make when talking about quantum states. It might seem like whether they’re real has little to no bearing in our daily lives. But they do seem to make a difference for experimenters and quantum computing engineers. They have to take the dynamics implied in these mathematical tools seriously. In the case of quantum computing, it’s the very dynamics that seem to enable what they’re trying to do. Failure to treat them as real has consequences.

    Now, I’m a structural realist. I think what we can count on being real in successful scientific theories are the structures they describe, at least to some level of approximation. That doesn’t mean we can count on them being fundamental, or that we know what they may be structures of. This is particularly important to remember with quantum theory, where the structures are all we currently have.

    Does that mean that, rather than being structures of objective reality prior to a measurement, they could actually be structures of subjective expectations as the QBists argue? Or of the way the experimental equipment has been set up, as other antirealists argue? I suppose so. But that seems to imply the possibilities are completely set by these expectations or preparations, that if scientists really wanted to, they could get any result they wanted.

    In practice, something seems to constrain the possible results. Of course, if I put on the epistemic hat, I could argue that those constraints are the constraints on their thoughts (QBism) or practical equipment limitations (other epistemics), not anything in the quantum realm. But taking this literally, that seems to imply that quantum physics is a big illusion, a side effect of the way scientists think or construct experiments. If so, how could anyone be sure that any scientific measurements beyond human senses are to be trusted?

    All of that is before remembering that if we think anything objective at all is happening in the physics prior to a measurement, that there are mathematical theorems which kick in and demonstrate that quantum states must describe something real. Epistemic interpretations of quantum mechanics, such as Copenhagen, QBism, and RQM avoid this be saying there is no such objective physics prior to measurement (or interaction). Which, to me, makes calling them “epistemic” misleading. Qbists in particular argue for a “participatory reality,” a notion they inherited from John Wheeler’s “it from bit” idea.

    This selective application of antirealism has always felt like gerrymandering to me. Most of the proponents want to resist the idealism label, but they seem to want to take from metaphysical antirealism just what they need to avoid quantum state realism. It all feels forced.

    Interestingly enough, that doesn’t appear to have been Niels Bohr’s take. Historians often argue that he was more of a neo-Kantian than either an instrumentalist or idealist. His take seemed to be that the quantum realm was real, but inaccessible, the noumena always beyond the phenomena. Of course, this predates the theorems I mentioned above, which is what forces stronger stances from contemporary epistemic proponents.

    But my issue with the Kantian view is it pushes reality into something utterly and forever unknowable. Reportedly, Kant’s motivations for doing this were to preserve space for God, the soul, free will, and morality in response to the “Crisis of the Enlightenment,” which seemed to call all of those things into question. I suspect neo-Kantians are trying to preserve different things, but that kind of preservation likely remains part of their motivation.

    But the cost of doing so is to remove the practical aspects I noted above when deciding what’s real or not. In my view, it removes any utility from the concept of reality, except for talking in terms of theology or overall metaphysics.

    Which may be why Arroyo and Arenhart want to use the word “pragmatic” instead. I think a better strategy is to retain our grounded everyday meaning for “real,” but admit that we never know whether we’ve reached ultimate reality. But this is coming from someone who doesn’t share the Kantian or neo-Kantian concerns.

    Overall, my theory of reality is pragmatic. But I continue to wonder, for the people arguing against that take, what standard are they using?

    What do you think? Are there issues with a pragmatic take on reality I’m overlooking? If so, what would be a better standard?

    #antirealism #Philosophy #PhilosophyOfScience #Physics #QuantumMechanics #realism #Science #structuralRealism

  16. Why Even Physicists Still Don’t Understand Quantum Theory 100 Years On

    Wiktor Mazin. Credit: Wiktor Mazin, Quantum Fractal Artist Everyone has their favourite example of a trick that reliably gets a certain job done, even if they don’t really understand why. Back in the day, it might have been slapping the top of your television set when the picture went fuzzy. Today, it might be turning your computer off and on again. Quantum mechanics the most successful and important theory in modern physics is like that. It works wonderfully, explaining things from lasers […]

    onlinemarketingscoops.com/2025

  17. Macroscopic Theories Of Matter And Fields A Thermodynamic Approach ( Advances in Science and Technology in the USSR)

    Advances in Science and Technology in the USSR
    Mathematics and Mechanics Series

    This is a collection of articles by Soviet scientists on current issues of building macroscopic models of matter and fields. Based on thermodynamics concepts the papers develop general variational techniques of modeling material continuous media and fields allowing for their interactions in reversible and irreversible processes. The book is intended for researchers, engi­neers, graduate and postgraduate students interested in the mechanics of continuous media.

    Translated from the Russian by Eugene Yankovsky

    You can get the book here and here.

    Twitter: @MirTitles
    Mastodon: @[email protected]
    Mastodon: @[email protected]
    Bluesky: mirtitles.bsky.social

    Contents
    Preface, L. I. Sedov 7
    A Thermodynamic Approach to the Basic Variational Equation for Building Models of Continuous Media, L. I. Sedov 19
    Applying the Basic Variational Equation for Building Models of Matter and Fields, L. I. Sedov 43

    Introduction 43
    Definitions 43
    Variations of Tensors for Which Scalar Invariants Retain Their Form 46
    Special Types of Tensor Components Qlj 48
    Defining Variations and Their Interrelationship in the Comoving and the Observer’s Reference Frame 50
    Auxiliary Formulas for Variations 55
    Given Scalar and Tensor Parameters Characterizing Models of Material Media and Fields 56
    The Determining Parameters in the Characteristics of a Continuous Medium as a Whole and the Characteristics of Individual World Lines 60
    The Basic Variational Equation and Identities Following from the Scalar Nature of the Lagrangian Density 62
    The Euler Equations for the Basic Variational Equation (2.8.1) 66
    The Conditions at Strong Discontinuities 71
    On Models of Fluids 74
    An Elastic-Body Model 79
    Constructing Models of Fields 81
    A Model of Interacting Material Medium and Electromagnetic Field 83
    Examples 90
    Transition from Relativistic to Newtonian Mechanics in the Presence of Irreversible Processes, L. T. Chernyi 98
    The Basic Vibrational Equation 98
    The Euler Equations and Conditions on Discontinuities 102
    Transition to Newtonian Mechanics 106
    Irreversible Processes 108
    Conclusion 114
    Models of Ferromagnetic Continuous Media with Magnetic Hysteresis, L. T. Chernyi 116

    Introduction 116
    The Determining Parameters 118
    The Variational Principle and the Main Equations 121
    A Phenomenological Theory of Irreversible Processes 126
    Some Corollaries of the General Theory 130
    Examples of Models of Magnetizable Media 137
    Magnetizable and Polarizable Media with Microstructure, V. A. Zhelnorovich 141

    The Determining Parameters of Magnetizable and Polarizable Media with Microstructure 141
    Relaxation Models of Magnetizable and Polarizable Media Without Microstructure 150
    Models of Magnetizable Liquids with Intrinsic Moment of Momentum 156
    Couette Flow of an Incompressible Viscous Magnetizable Liquid 156
    Poiseuille Flow in Cylindrical Channel 157
    Magnetoacoustic Waves in Magnetizable Liquids 160
    On Exact Solutions for Interacting Gravitational and Electromagnetic Fields, G. A. Alekseev 168

    Introduction 168
    The Einstein-Maxwell Equations in Matrix Form 169
    Building the Associated Linear System and the Reduction Conditions 172
    Soliton Solutions of the Einstein-Maxwell Equations 176
    One-Soliton Solutions with Minkowski’s Space-Time as Background 180
    Interaction of Solitons with a Uniform Electromagnetic Field 184
    Neutrino Fields in General Relativity, N. R. Sibgatullin 187

    Introduction 187
    Canonical Equations of Neutrino Fields and Waves 188
    On the Infinite Dimensional Algebra and the Lie Group of Neutrino Vacuum Equations 199
    Exact Solutions of Neutrino Vacuum Equations 208
    Rotation of the Polarization Vector of Gravitational Waves in a Burst of Neutrino Radiation 220
    Tensor Representation of Spinor Fields, V. A. Zhelnorovich 224

    Introduction 224
    Dirac Matrices 224
    The Spinor Representation of the Lorentz Group 226
    Spinors in Four-Dimensional Pseudo-Euclidean Vector Space 231
    Conjugate Spinors 233
    The Relation Between Even-Rank Spinors and Tensors 234
    The Relation Between First-Rank Spinors and Systems of Complex Tensors 234
    Real-Valued Tensors Determined by a Spinor 238
    Rotations in Four-Dimensional Space and Spinors 240
    Invariant Spinor Subspaces 243
    Spinors in Three-Dimensional Euclidean Space 244
    Tensor Representation of Spinors in Three-Dimensional Euclidean Space 246
    Rotations in Three-Dimensional Space and Spinors 248
    Tensor Representation of Differential Spinor Equations in the Minkowski Space 250
    Some Solutions of Differential Equations for Relativistic Models of Magnetizable Fluids with Intrinsic Angular Momentum in an Electromagnetic Field 254
    Index 26

    #elementaryParticles #generalRelativity #mirPublishers #physics #quantumMechanics #sovietLiterature #variationalPrinciples

  18. Everything is an intersection of #Lagrangian #submanifolds, implying fundamental #locality. The apparent non-localities in #QuantumMechanics, arising from #measurement #incompatibility, suggest that at a deeper level, quantum mechanics is equivalent to classical #ergodic systems.