I finally saw #QuantumMechanics with my own eyes... (It's spookier than I expected) https://youtu.be/KfODG5REyss?si=TQ0TYznfzj4SQvyo
#quantummechanics — Public Fediverse posts
Live and recent posts from across the Fediverse tagged #quantummechanics, aggregated by home.social.
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“It is wrong to think that the task of physics is to find out how nature is. Physics concerns what we can say about nature.”*…
Einstein fought to save our everyday notion of reality from the strangeness of quantum mechanics. But, as Charlie Wood reports, those who set out to aid him keep poking holes in his argument…
One of a human’s earliest developmental milestones is an understanding of object permanence. It generally takes less than a year for a baby to realize that when an adult hides their face behind their hands in a game of peek-a-boo, they don’t cease to exist. There’s more to the world around us than what we perceive.
This suggests — or at least, it suggested to Albert Einstein — that the world is “real,” in the sense that things in the world have properties that are intrinsically true no matter what anyone thinks. A red billiard ball is red, even in the dark, and even if no one is checking its color. The redness is a property belonging to the ball, not to some device measuring the ball, and not to the mind of some person operating the measuring device.
Yet quantum mechanics, a thoroughly validated theory of how the world works, seems to suggest otherwise. The theory’s math assigns redness to the billiard ball at the moment you measure it. Before then, the theory gives you only a set of probabilities telling you what color the ball might be. Key founders of quantum mechanics suggested that this math reflects the nature of reality — that in some sense, a single, objective reality doesn’t really exist.
In 1935, Einstein rebelled against this surreal reading of quantum theory, proposing one of the 20th century’s most famous thought experiments. But his rebellion was doomed. In 1964, the physicist John Stewart Bell showed with a thought experiment of his own that reality had to be stranger than Einstein assumed. Subsequent work would put Bell’s thought experiment to the test — and prove him right.
Then, 50 years after Bell, Matthew Pusey, at the time a graduate student at Imperial College London, took on what remained of Einstein’s notion of reality and — without originally intending to — delivered the killing blow.
The paradigm-shifting theorem became known as PBR, for Pusey and his academic accomplices, Jonathan Barrett and Terry Rudolph. Since the publication of PBR in 2012, many theorists have come to accept that it rules out our most commonsense understanding of reality.
“From the moment [PBR] came out, people knew it would be a landmark,” said Jacques Pienaar, a physicist now at the Federal University of Rio de Janeiro in Brazil.
At the time, Pienaar, like Pusey, had been walking in Einstein’s footsteps, dabbling in theories designed to show that objective reality exists and that quantum mechanics merely describes our incomplete knowledge of it. But when the PBR theorem appeared, Pienaar remembers thinking, “That’s it. The program’s dead.”
This is the story of how Einstein, Bell, and finally Pusey and his collaborators killed reality as we know it. In three theorems, they proved that quantum mechanics is incompatible with the world we perceive. And since experiment after experiment — including a recent realization of PBR — has established that quantum mechanics is the law of the land, something about reality has to go.
The question that remains is: How much do we have to give up?…
[Wood recounts the fascinating history of attempts to grapple with the issue, which have, cumulatively, strengthened the conclusions (and thus implications) of PBR. As to those implications, he concludes…]
… Many physicists have taken PBR to mean that the quantum state must be real — an objective property living in particles, people, and planets. If so, impossible-seeming events like collapse must also have some physical correlate. This stance amounts to taking the extreme path of Bohmian mechanics and other “realist” interpretations. As Pusey pithily puts it, PBR guarantees that “if anything is real, the quantum state is real.”
But to conclude that the quantum state is definitely real is to misunderstand the PBR theorem, because PBR also leaves open the other extreme path: It could be, as the Copenhagenists have steadfastly maintained since the days of Bohr, that in some sense nothing is real, including the quantum state. It’s perfectly possible that the quantum state lives in our minds and has no direct connection to an objective reality. In this case, the redness of the billiard ball would be inextricably linked with the act of observing it — precisely the state of affairs that so deeply offended Einstein. “Do you really believe the moon is not there when you are not looking at it?” Einstein once famously pressed his colleague Abraham Pais.
PBR doesn’t give us the answer. What it does do is end a century of bargaining with quantum mechanics. By ruling out the possibility that reality is real while the wave function is not, PBR requires that physicists either fully embrace the notion of an objective but entirely surreal reality, or fully reject objective reality altogether. “Do you bite the bullet, or do you try and dodge the bullet?” Pusey said.
Pienaar was one of the few physicists who were still playing around with middle-of-the-road theories, though with waning interest. PBR contributed to his choice to give up on objective reality once and for all. He switched to a modern offshoot of Copenhagenism known as QBism.
QBism asserts that the world itself may exist, but quantum mechanics can’t describe it. All the theory can really do is capture our relationship to — and subjective experience of — the world. “You need two to tango,” Pienaar said. “Without two systems, there’s no relation. And reality is nothing but relations.”
And yet, some physicists remain unsatisfied with the two extreme options: a surreal reality or no reality. So they are beginning to pick at the fine print on the technical definition of reality. “Maybe the correct way of thinking about a state of reality is something a bit more woolly, that doesn’t quite fit into this straitjacket,” Pusey said.
In this spirit, Hardy questions whether reality needs to necessarily have a single, objective state at every given moment. Perhaps states could somehow spread out across multiple moments. He doesn’t yet have a fully fleshed-out proposal, but his goal is to come up with a deeper, more general notion of reality that is still recognizable.
If underdogs like Hardy succeed in saving some notion of reality, it won’t quite be the one Einstein wanted; Bell and PBR guarantee that. But it may yet turn out to be the sort of reality Einstein needed, one that makes enough intuitive sense to win the hearts and minds of physicists, especially those fatigued from a lifetime of labyrinthine debates about what is real. “It needs to have the ring of truth, so that when people see it, they can’t unsee it,” Schmid said.
Curiouser and curiouser: “A Strange Quantum Theorem Has Killed Einstein’s Reality,” from @walkingthedot.bsky.social in @quantamagazine.org.
* Niels Bohr, who also famously– and relevantly– observed: “Those who are not shocked when they first come across quantum theory cannot possibly have understood it.”
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As we get real, we might recall that it was on this date in 1974 that the discovery of the “charmed quark” subatomic particle was announced simultaneously by the two American experimental groups responsible: an MIT group at Brookhaven National Laboratory, and a SLAC-Berkeley group at the Stanford Linear accelerator center.
The existence of the charm quark was first predicted by James Bjorken and Sheldon Glashow in 1964. The new particle, made up of a charm quark and its antimatter opposite, anti-charm, was the fourth quark to be indentified; with a mass of 3095 MeV (or 1.27±0.02 GeV/c2), it had a lifetime about 1000 times longer than that of other particles of comparable mass. Its announcement set the world of high energy physics on fire and is now known in the physics community as “the November revolution.”
For their photo-finish discoveries, the scientists leading those groups, Samuel Ting and Burton Richter, were awarded the Nobel Prize in Physics in 1976.
#Charm #culture #Einstein #history #JohnStewartBell #MatthewPusey #objectiveReality #particlePhysics #PBR #Physics #quantumMechanics #quantumTheory #quark #reality #Science -
The quantum-geometric nonlinear Hall (QgNLH) state is an unconventional quantum transport phenomenon where the transverse Hall voltage response scales with the cube of the applied electric current rather than proportionally.
#CondensedMatterPhysics #QuantumMechanics #Spintronics #MaterialsScience #Electromagnetism #sflorg
https://www.sflorg.com/2026/11/phy11052601.html -
Researchers have discovered a method to control the atomic structure of quantum materials, specifically sliding ferroelectrics like tungsten ditelluride, using targeted sequences of time-delayed ultrashort laser pulses.
#CondensedMatterPhysics #FemtosecondPhysics #MaterialsScience #Optoelectronics #QuantumMechanics #sflorg
https://www.sflorg.com/2026/11/phy11042601.html -
I've started feeling interested in Quantum Mechanics again. This time I'm showing how two electrons cannot occupy the same valance shell when they have the same spin. They must be oriented at different spins to occupy the same valance band
#art #artist #illustrator #illustrated #quantummechanics #electromagnetism #maths #physics #mastoartist #mastoart
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`This quantity captures the spreading of a time-evolved operator in the space of all possible operators on the Hilbert space, which is doubly exponential in the number of degrees of freedom. It thus provides a finer notion of operator spreading than the well-understood phenomenon of operator growth in physical space.`
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100 years ago #OTD the #fermion was born, kind of: detailled story (in Spanish) in https://guillermoabramson.blogspot.com/2026/10/100-anos-de-fermiones-y-enanas-blancas.html #QuantumMechanics
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Quantum Computing by 2029? It's possible. Is this going to turn into another 'fusion is 20 years away' meme? We'll see.
#quantum #quantumphysics #physics #science #quantummechanics #astrophysics
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`Here, using nearly integrable ultracold Bose gases, we realize such intermixtures of Bethe strings out of equilibrium, by dynamically tuning interactions from repulsive to attractive. We measure the average binding energy of the strings, revealing the presence of bound states of more than six particles.`
https://doi.org/10.1038/s41467-026-76018-0
#physics #quantumMechanics #quantumPhysics #Bethe #BetheStrings
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**Fractal Time reveals consciousness as non‑local, suggesting space‑time emerges from a scale‑invariant reality.**
Dr. Brent Allen Jensen's essay explores how self‑similar patterns across brain scales—mirrored in EEG and neurophysiology—imply a profound ontological shift. Join the conversation on the frontiers of #Ontology #Philosophy #Consciousness #QuantumMechanics #EmergentMind #PhilosophyOfMind.
https://telegra.ph/The-Ontological-Frontier-Does-The-Self-Similar-Pattern-Of-Fractal-Time-Imply-That-Consciousness-Is-Fundamentally-Non-Local-And-T-10-11 -
". . . what we observe is not nature itself but nature exposed to our method of questioning." Werner Heisenberg
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“A physicist is just an atom’s way of looking at itself”*…
Encouraged by successes in understanding black holes, theoretical physicists are applying what they’ve learned to whole universes. As Matt von Hippel explains, what they’re finding has them questioning fundamental assumptions about how physics ought to be done…
Tinkering at their desks with the mathematics of quantum space and time, physicists have discovered a puzzling conundrum. The arcane rules of quantum theory and gravity let them imagine many different kinds of universes in precise detail, enabling powerful thought experiments that in recent years have addressed long-standing mysteries swirling around black holes.
But when a group of researchers examined a universe intriguingly like our own in 2019, they found a paradox: The theoretical universe seemed to admit only a single possible state. It appeared so simple that its contents could be described without conveying even a single bit of data, not even a choice of a zero or a one. This result clashed with the fact that this type of universe should be capable of hosting black holes, stars, planets — and people. Yet all those rich details were nowhere to be seen.
“We look around, and certainly the world seems more complex than that,” said Rob Myers, a theoretical physicist at the Perimeter Institute for Theoretical Physics in Waterloo, Canada, who has not been directly involved in this research.
Physicists have good reason to trust the calculation, which builds on fundamental physical ideas. The math implies a universe with only one state; our universe is clearly not like that. Now a team of theorists has floated a possible answer. The paradoxical result occurred when physicists sought an objective description of the state of an entire universe. But a description like that might not be possible, even in principle. It implicitly assumes a universe that exists without an observer to observe it. And perhaps without observers, the complexity of the universe loses its meaning…
[von Hippel unpacks the scientific thinking that led to this conundrum. He concludes with an account of recent work by Ying Zhao that hints at a resolution…]
… Quantum mechanics requires a distinction between an observer — such as the scientist carrying out an experiment — and the system they observe. The system tends to be something small and quantum, like an atom. The observer is big and far away, and thus well described by classical physics… Perhaps an observer could do the same to these closed, impossibly simple-seeming universes?
In 2024, Zhao moved to the Massachusetts Institute of Technology, where she began to work on the problem of how to put an observer into a closed universe. She and two colleagues —Daniel Harlow and Mykhaylo Usatyuk — thought of the observer as introducing a new kind of boundary: not the edge of the universe, but the boundary of the observer themself. When you consider a classical observer inside a closed universe, all the complexity of the world returns, Zhao and her collaborators showed.
The MIT team’s paper came out at the beginning of 2025, around the same time that another group came forward with a similar idea. Others chimed in to point out connections to earlier work.
At this stage, everyone involved emphasizes that they don’t know the full solution. The paradox itself may be a misunderstanding, one that evaporates with a new argument. But so far, adding an observer to the closed universe and trying to account for their presence may be the safest path.
“Am I really confident to say that it’s right, it’s the thing that solves the problem? I cannot say that. We try our best,” Zhao said…
“Cosmic Paradox Reveals the Awful Consequence of an Observer-Free Universe,” from @quantamagazine.org.
Apposite: “Biology Might Not Be Quantum, but Its Math Is Quantumlike“
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As we keep an eye out, we might send cosmological birthday greetings to Enrico Fermi; he was born on this date in 1901. A physicist and Nobel Laureate (1938) for his discovery of nuclear reactions brought about by slow neutrons, he is best remembered for (literally) presiding over the birth of the Atomic Age. Fermi was perhaps especially remarkable as the last “double-threat” in his field: a genius at creating both important theories and elegant experiments. As observed before (and illustrated above :), the division of labor between theorists and experimentalists has since been pretty complete.
The novelist and historian of science C. P. Snow wrote that “if Fermi had been born a few years earlier, one could well imagine him discovering Rutherford’s atomic nucleus, and then developing Bohr’s theory of the hydrogen atom. If this sounds like hyperbole, anything about Fermi is likely to sound like hyperbole.”
#AtomicAge #blackHoles #culture #EnricoFermi #Fermi #history #Mathematics #observer #philosophy #Physics #quantumMechanics #quantumTheory #reality #Science #Universe -
Theory: #Bigfoot is a macroscopic #quantum object in superposition coupled to camera autofocus. But the collapse isn't 50/50. Every camera resolves him to "doesn't exist." Observation doesn't just measure Bigfoot - it actively selects against him. #Cryptid #QuantumMechanics #Cryptid #cryptozoology
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Dark Side of the Moon just took on a whole new meaning ...
https://www.sciencedaily.com/releases/2026/09/260921081054.htm
#quantum #quantumphysics #physics #science #quantummechanics #astrophysics
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FINALLY: A Proof that Particles Take All Paths At Once? Via @sabinehossenfelder for @sciencewtg #Science #Physics #QuantumPhysics #QuantumMechanics #ParticlePhysics 🔭🔬🧪🥼🧑🔬 youtu.be/A2ImadKWaHA?...
FINALLY: A Proof that Particle... -
🎩✨ Oh, joy! Another paper proving the existence of quantum wizardry by stringing together "higher-order operator correlators" like it's a magic spell. Because, clearly, the cosmos and quantum mechanics were just begging for some crossover fan fiction. 🌀🔮
https://arxiv.org/abs/2609.05472 #quantumwizardry #quantummechanics #higherordercorrelators #fanfiction #sciencehumor #magicalthinking #HackerNews #ngated -
1/n Notes on #Physics and Frontiers: We should at least understand that, not having met some fundamental challenges that reside within the #StandardModel the assumption that we have exceeded its capacity to engender what we are seeing is mostly hubris. Instead we should pull back and note that physics off the shell can still be fairly encompassed by the SM. In this case it’s us, and not the model, that are failing.. #QuantumMechanics and #Relativity both reside within its purview and we…
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Einstein’s “spooky action” just survived one of physics’ most extreme tests. Via @sciencedaily_official #Science #Physics #QuantumPhysics #QuantumMechanics 🔭🔬🧪🥼🧑🔬
Einstein’s “spooky action” jus... -
Schrödinger’s muse: Cleverness as a strategy for popularizing physics
A few years before Erwin Schrödinger's cat fable-turned-meme of 1935, he delved into a style of science communication all his own. Writing for Koralle magazine, a popular science weekly in Berlin, Schrödinger took readers on a rhetorical jaunt through the peculiarities of natural science. Physics, his muse, was a terrible subject for leisure reading. Made popular by Einstein's relativity revolutions of 1905 & 1915, early attempts at explaining physics to the public defied comprehension. […] -
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 9Chapter 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 175Chapter 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 225Chapter 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 359Chapter 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 452Chapter 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 492Chapter 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 525Chapter 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 623Appendix. 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 -
RELATIVITY FASTER THAN LIGHT
FTL FROM REDUCING THE DOMAIN OF DEFINITION OF THE LORENTZ TRANSFORMATION
Abstract: Quantum Entanglement has been experimentally demonstrated with utmost certainty to go Faster Than Light. However, Special Relativity is conventionally said to exclude faster-than-light signaling because Lorentz transformations can reverse the temporal order of spacelike-separated events. We readjust Relativity to make it Entanglement compatible.
For an explicit FTL signal with (u=2c), a perfectly ordinary Lorentz transformation indeed assigns a negative reception time in a sufficiently rapidly moving inertial frame.
But this does not demonstrate that physical time travel occurs; it demonstrates that coordinate-time ordering is frame-dependent for spacelike intervals.The essay argues that the real assumption requiring examination is not the mathematics of the Lorentz transformation, but its unrestricted physical interpretation.
If FTL influences exist, they need not be required to possess the same relativistic transformation properties as ordinary subluminal processes (and they should not as they potentially come from completely different physics)..The proposed solution is to introduce a preferred Cosmic Manifest Frame (CMF), identified approximately by the Cosmological Microwave Background, CMB, in which FTL propagation and causal ordering are physically defined.
Other inertial frames may assign negative coordinate times to the same FTL process, but those coordinates do not represent reversed physical causality.
Lorentz symmetry is thereby retained as an effective symmetry for domains where it has been experimentally validated, and theoretically deduced, while it is denied fundamental universality.
SQPR adopts precisely such a preferred causal structure, with nonlocal quantum influences propagating at a finite superluminal speed such as TAU (>>>>> c).
The proposal thus attempts to separate the mathematical freedom of spacetime coordinates from the physical ordering of causes and effects.***
We consider first a concrete numerical example of a specific superluminal speed to make the conventional argument found in Special Relativity textbooks (which we think is erroneous) completely explicit.
The standard argument against Faster Than Light SIGNALING goes as follows:
“Given Special Relativity, SR, if you allow faster‑than‑light signaling, then the Lorentz transformation between inertial frames implies that some observers will see the signal arrive before it is sent. With two such FTL signals, you can construct a closed causal loop, i.e. a form of ‘time travel’ that violates causality.”
We will show that the “closed causal loop” construction is superfluous to make this (erroneous) argument work. The traditional argument can be made more compact, no need for a loop. This irony is significant, because the existence of a sharper (erroneous) argument against FTL from SR shows that the physicists who pretend to have demonstrated that FTL is impossible from SR have not bothered to find the sharpest argument, possibly indicating that they find the subject unappetizing… Or could it be that they were afraid to be cut by the sharpness of the argument, because, as it turns out, the argument doesn’t even need a causal loop? … It’s that basic…
First let’s give a concrete example. Let the Faster than Light (FTL) signal speed be u = 2c. And let the speed of S’ relative to S be .6c. And the separation L be two light second (twice Earth-Moon). Computation shows that, BLINDLY using the Lorentz transformation, the FTL signal is received in S’ at MINUS .25 second. In other words, time travel.
We argue that this is absurd, and caused by a misuse of the Lorentz transformation by overextending its domain of definition over the spacelike subset of Poincaré spacetime. (Poincaré discovered and used Poincaré spacetime and its metric months or years before those who plagiarized him. In particular Poincaré found the full Lorentz Transformation, LT, using the most general argument; this is important because, in spite of his success using it, clearly Poincaré took Poincaré spacetime with a grain of salt; the present essay explains a plausible reason why; there is another; later, following Poincaré once again, Einstein confessed he didn’t like Poincaré spacetime… Make no mistake: Poincaré’s argument about getting LT from Poincaré spacetime was entirely mathematically correct; what was not done is the physical restriction we undertake below).
Recapitulation in the general case:
We set the frame S and S’ such that their space and time origin coincide x = x’ = t = t’ = 0. That’s event A. Event B is at (L,T) in S, such that L/T = u, superluminal: u > c.
What is the time of B in S’? T’(B) is: (T – v L/cc)γ
If the signal is FTL, L> cTL. Then there exists some subluminal v high enough such that:
(T− vL/cc) < 0…. Thus t’(B) < 0.
In other words the FTL signal is received at a negative time in S’ … thus before it is sent.
This is my sharper version of the erroneous argument many physicists have made against FTL.
***
GRAND RETURN OF ABSOLUTE SPACE:
Solution to the riddle of the Lorentz Transformation creating events which have not happened yet: Reject the claim that all inertial frames are equivalent In other words, as observed in Physical Reality, I mean the cosmos out there, there is a preferred frame in the universe, the one in which the CMB is at rest. (Mach and Newton would opine that this absolute space gives us some hope of explaining inertia. Einstein developed General Relativity in the hope of explaining inertia… He completely failed in that hope, but then we got GPS from GR…)
So postulate a special frame in which FTL is defined and causality is enforced. This is the path of SQPR.
In other frames, you might get “backwards in time” coordinates, but you declare that only the preferred frame’s ordering is physically meaningful.
This does not even abandon standard Special Relativity formally, and certainly not in practice (all the usual formulas are still effective, say for GPS, but one cannot extend the domain of the Lorentz Transformation over the space-like domain). SR has no difficulty representing spacelike intervals.
What we reject formally is the additional assumption that an FTL physical influence must transform exactly like an ordinary subluminal signal, with every inertial observer’s time coordinate having equal causal status.
The Lorentz transformation is mathematically valid on spacetime, but its physical interpretation as a symmetry of every possible causal process need not be valid. Clearly when Poincaré published on June 5, 1905, the Lorentz Transformation as a rotation of Poincaré spacetime, he could not have guessed the EPR argument of 1935 of the demonstration of FTL by Aspect in 1982 (the latter proving that there are causal processes which are not confined by the speed of light; this outside of the domain of the Lorentz Transformation).
***
We can send (not yet controlled) information faster than light (Bell style experiments). Yes the orientation of the device at A has a real physical effect at B, even if the interval AB is spacelike. That has been amply proven theoretically and experimentally.
We do not reject Poincaré spacetime… After all, it’s the geometrodynamics of light in the first approximation! But it’s just a first approximation; by the way, that seems to have been the point of view of his creator Henri Poincaré, that’s why he talked about the “ether” so much… Similarly Einstein admitted that, in General Relativity, the speed of light varies… The “ether” was a placeholder concept for the sort of hyperspace in which Physical Reality is embedded and that yours truly advocates for…
There are very deep math reasons for this; the math was not yet developed at the time but Poincaré, the world’s greatest topologist then, may have guessed them..
Instead we posit a preferred frame, the CMF, Cosmic Manifest Frame, as given by the CMB, the Cosmic Microwave Background. Call CMF by the letter S (for Stationary).
- Causality is fundamentally defined.
- FTL influences propagate with some speed u>c. In the case of SQPR one cosmic quantum collapse/entanglement speed is hypothesized: TAU.
- The Lorentz transformation is an effective symmetry only for certain classes of phenomena (e.g. electromagnetism), not a fundamental symmetry of all physics…. Just like light is not all of physics, and sure has little to say about the QUANTUM ENTANGLEMENT machinery it is subjected to (see Aspect Nobel Prize winning FTL experiments).
This is exactly the loophole that avoids the “FTL ⇒ time travel” argument.
By the way, this restriction of the Lorentz Transformation proposed here will no doubt do wonders to help avoiding causal time like loops around Black Holes…
As we are into grandiose semi poetic evocations, let’s go all the way. I have an entanglement-clock argument: which questions the elevation of coordinate time to fundamental physical time. In the present essay, I similarly question the elevation of Lorentz-frame equivalence to a universal causal principle.
That gives the essay a much deeper unifying thesis: coordinate transformations need not dictate physical causality. (Ironically that idea is nothing new: it led to the creation of Special and General Relativity; what’s new is to push it beyond the old epistemological frontiers, taking FTL and Entanglement seriously…)
Patrice Ayme
#Causality #CMB #CMF #Consciousness #CosmicManifestFrame #Entanglement #EPR #FasterThanLight #HenriPoincaré #LocalTime #LorentzTransformation #Philosophy #PhysicalReality #Physics #PoincaréSpacetime #QuantumMechanics #Relativity #Science #Time -
Quantum physicist takes aim at the arrow of time
Scientists and philosophers have argued over the nature of time since ... well, since time immemorial.Does time flow unceasingly in one direction? Is our perception of time merely an illusion? Does each instant exist eternally, a
https://cosmiclog.com/2026/08/31/quantum-physicist-takes-aim-at-the-arrow-of-time/
#FictionScienceClub #Books #CLUBClub #FictionScience #JimAlKhalili #Multiverse #Physics #QuantumMechanics #Science #TimeTravel -
Researchers have discovered a mechanism to overcome the traditional energy limit (the energy cutoff) in X-ray production by using helium atoms irradiated with intense ultraviolet (UV) lasers. In this process, two quantum-mechanically correlated electrons recombine with an ion simultaneously, releasing their combined energy as a single, higher-energy X-ray photon.
#Physics #QuantumOptics #Photonics #AtomicPhysics #QuantumMechanics #sflorg
https://www.sflorg.com/2026/08/phy08272601.html -
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 https://zenodo.org/records/21970203
#Sonoluminescence #Physics #Mathematics #GeneralRelativity #QuantumMechanics #QuantumGravity
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Two Dimensions of Time Explain Quantum Physics, Physicist Argues. Via @sabinehossenfelder for @sciencewtg #Science #Physics #QuantumPhysics #QuantumMechanics 🔭🔬🧪🥼🧑🔬 youtu.be/8e_JSOxaEVQ?...
Two Dimensions of Time Explain...