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You (and he) need to distinguish between (e.g. Boltzmann) noise and (Heisenberg) fundamental indeterminacy.ΔpΔx = h determines the mechanical structure of a resistor. kT determines the random noise it generates.
From the copper spines of antennas to the invisible dance of light, our conversation with Dr. Hans Schantz traces the story of physics most students never hear about. Dr. Schantz, a theoretical physicist turned engineer who studied under John Wheeler, unpacks the forgotten role of physical mediators in electromagnetism and what modern antenna design can reveal about light itself. Along the way, we wander through the epic moments of the 20th century quest for understanding light, from aether theory to pilot waves, connecting lost ideas to cutting-edge engineering. This is a signal worth listening to.00:00 Go! Antenna Design and Light00:06:02 Historical Context: The Development of Fields in Physics00:11:30 The Evolution of Physics: From Newton to Abstract Principles00:17:05 Induction vs. Deduction in Scientific Methodology00:24:02 The Quest for Universal Understanding in Physics00:28:34 The Shift from Ether to Relativity00:34:05 The Conflict Between Theory and Observations00:39:38 Historical Oversights in Physics00:46:14 The Singular Nature of Electromagnetic Fields00:48:03 History of Electromagnetism and Influential Figures00:51:04 Einstein and the Concept of Ether00:56:06 Quantum Mechanics and Debate with Einstein01:00:45 The Impact of Positivism on Physics01:09:01 Misguided Applications of Quantum Mechanics01:11:44 Oppenheimer's Seminar and Pilot Wave Theory01:18:06 Fundamental Crisis in Physics01:21:21 Understanding Antennas and Light01:30:05 Journey to Antenna Design01:33:46 Near Field Electromagnetic Ranging01:34:13 Signal Propagation and RF Fingerprinting01:36:04 Electromagnetic Wave Properties01:39:17 Q Factor and Energy Decoupling in Antennas01:42:50 Effects of Medium on Transmission01:46:45 Aether and Early 20th Century Experiments01:50:33 Complexity of Electric and Magnetic Field Coupling01:53:01 Phase Dynamics in Antenna Systems01:56:54 Atomic Radiation as Antenna Behavior01:57:36 Discussion of Quantum Mechanics and Atomic Behavior01:59:12 Antenna Models and Radiation Mechanisms02:01:24 Speculative Theories on Signal Transmission02:04:47 Advancements in Understanding Electromagnetic Systems02:10:31 Energy Dynamics in Electromagnetic Interference02:14:38 Pilot Wave Theory and Its Connections02:19:23 The Nature of Waves and the Concept of Medium02:21:39 Discovery of Gamma Rays from the Earth02:22:47 Opposition to Pilot Wave Theory02:27:03 Understanding Radiation Reaction02:30:11 Antenna Behavior and Radiation02:32:03 Electromagnetic Fields and Energy Dynamics02:34:44 Exploration of Fundamental QuestionsABOUS US: Anastasia completed her PhD studying bioelectricity at Columbia University. When not talking to brilliant people or making movies, she spends her time painting, reading, and guiding backcountry excursions. Shilo also did his PhD at Columbia studying the elastic properties of molecular water. When he's not in the film studio, he's exploring sound in music. They are both freelance professors at various universities.
the invisible dance of light,
Quotethe invisible dance of light, ?
But surely light is not invisible, by definition?
In this journey towards Heisenberg's matrix formulation of quantum mechanics, here I present the origin of zero-point energy, one of the most bizarre predictions of quantum theory. Also known as vacuum energy, zero-point energy is a consequence of Heisenberg's uncertainty principle; however, its origin is a wrong theory and a wrong plot.Erratum: at 8:48 instead of "ln(1-p)^n" it should say "ln [p(1-p)^n]." This is just a typo, the rest of the calculation is correct. Thanks to @Miguel_Noether, @charlottedarroch and @martindimov3494 for reporting this.[References]∘ M. Planck, "Ueber eine Verbesserung der Wienschen Spectralgleichung," Verh. Dtsch. Phys. Ges. 2:202 (1900)∘ M. Planck, "Eine neue Strahlungshypothese," Verh. Dtsch. Phys. Ges. 13:138 (1911)∘ M. Planck, "?ber die Begr?ndung des Gesetzes der schwarzen Strahlung," Ann. Phys. 37 (4): 642 (1912)∘ M. Planck, "Loi du Rayonnement Noir," Proceedings of the First Solvay Conference in Physics, p.93 (1912)∘ H. S. Kragh and J. M. Overduin, "The Weight of the Vacuum," SpringerBriefs in Physics (2014)∘ A. Einstein and O. Stern, "Einige Argumente f?r die Annahme einer molekularen Agitation beim absoluten Nullpunkt," Ann. Phys. 40 551 (1913)∘ A. Eucken, "Die Molekularw?rme des Wasserstoffs bei tiefen Temperaturen," Verh. Dtsch. Phys. Ges., Nr. 4:141 (1912)∘ P. Ehrenfest, "Bemerkung betreffs der spezifischen W?rme zweiatoniger Gase," Verh. Dtsch. Phys. Ges. 15, 451 (1913)∘ D. M. Dennison, "The Rotation of Molecules," Phys. Rev. 28, 318 (1925)∘ C. A . Gearhart, "Astonishing Successes and Bitter Disappointment: The Specific Heat of Hydrogen in Quantum Theory," Arch. Hist. Exact Sci. 64:113 (2010)∘ R. S. Mulliken, "The Band Spectrum of Boron Monoxide," Nature 114, 349 (1924)∘ R. S. Mulliken, "The Isotope Effect in Band Spectra, II: The Spectrum of Boron Monoxide," Phys. Rev. 25, 259 (1925)∘ D. C. Cassidy, "Heisenberg's First Core Model of the Atom: The Formation of a Professional Style," Hist. Stud. Phys. Sci. 10:187 (1979)
This is a step-by-step guide into Heisenberg's famous "Umdeutung paper" in which he created quantum mechanics in 1925. I include the experimental reason for the need of matrices, a deep dive into the four key ideas of Heisenberg's paper, and a detailed worked-out example showing how zero-point energy naturally appears in Heisenberg's theory thanks to an early draft of what years later would become Heisenberg's uncertainty principle. This video is my entry for #SoME4.[References]∘ W. Heisenberg, "?ber quantentheoretische Umdeutung kinematischer und mechanischer Beziehungen," Z. Phys. 33, 879 (1925)∘ W. Ritz, "On a new law of series spectra," Astrophys. J. 28, 237 (1908)∘ R. S. Mulliken, "The Isotope Effect in Band Spectra, II: The Spectrum of Boron Monoxide," Phys. Rev. 25, 259 (1925)∘ M. Born and P. Jordan, "Zur Quantenmechanik,? Z. Phys. 34, 858 (1925)
Thanks Jorge, This is a gem. Over the 63 years of playing with QM I always went for Schroedinger because I never caught on to the wonderful deductions Heisenberg made in this paper. I've only found out about Ladenberg through your videos. You have done a wonderful job of making things clear and with pencil and paper one can figure this out.
I love these videos so much. Nothing illuminates the seemingly obscure ideas behind QM better than a proper deep dive with all the historical context.
One hundred years after its birth, quantum mechanics remains one of the most powerful and successful theories in all of science. From quantum computing to precision sensors, its technological impact is undeniable ? and one reason why 2025 is being celebrated as the International Year of Quantum Science and Technology.Yet as we celebrate these achievements, we should still reflect on what quantum mechanics reveals about the world itself. What, for example, does this formalism actually tell us about the nature of reality? Do quantum systems have definite properties before we measure them? Do our observations create reality, or merely reveal it?These are not just abstract, philosophical questions. Having a clear understanding of what quantum theory is all about is essential to its long-term coherence and its capacity to integrate with the rest of physics. Unfortunately, there is no scientific consensus on these issues, which continue to provoke debate in the research community.That uncertainty was underlined by a recent global survey of physicists about quantum foundational issues, conducted by Nature (643 1157). It revealed a persistent tension between ?realist? views, which seek an objective, visualizable account of quantum phenomena, and ?epistemic? views that regard the formalism as merely a tool for organizing our knowledge and predicting measurement outcomes.Only 5% of the 1100 people who responded to the Nature survey expressed full confidence in the Copenhagen interpretation, which is still prevalent in textbooks and laboratories. Further divisions were revealed over whether the wavefunction is a physical entity, a mere calculation device, or a subjective reflection of belief. The lack of agreement on such a central feature underscores the theoretical fragility underlying quantum mechanics.The willingness to explore alternatives reflects the intellectual vitality of the field but also underscores the inadequacy of current approachesMore broadly, 75% of respondents believe that quantum theory will eventually be replaced, at least partially, by a more complete framework. Encouragingly, 85% agree that attempts to interpret the theory in intuitive or physical terms are valuable. This willingness to explore alternatives reflects the intellectual vitality of the field but also underscores the inadequacy of current approaches.Beyond interpretationWe believe that this interpretative proliferation stems from a deeper problem, which is that quantum mechanics lacks a well-defined physical foundation. It describes the statistical outcomes of measurements, but it does not explain the mechanisms behind them. The concept of causality has been largely abandoned in favour of operational prescriptions such that quantum theory works impressively in practice but remains conceptually opaque.In our view, the way forward is not to multiply interpretations or continue debating them, but to pursue a deeper physical understanding of quantum phenomena. One promising path is stochastic electrodynamics (SED), a classical theory augmented by a random electromagnetic background field, the real vacuum or zero-point field discovered by Max Planck as early as 1911. This framework restores causality and locality by explaining quantum behaviour as the statistical response of particles to this omnipresent background field.Over the years, several researchers from different lines of thought have contributed to SED. Since our early days with Trevor Marshall, Timothy Boyer and others, we have refined the theory to the point that it can now account for the emergence of features that are considered building blocks of quantum formalism, such as the basic commutator and Heisenberg inequalities.Particles acquire wave-like properties not by intrinsic duality, but as a consequence of their interaction with the vacuum field. Quantum fluctuations, interference patterns and entanglement emerge from this interaction, without the need to resort to non-local influences or observer-dependent realities. The SED approach is not merely mechanical, but rather electrodynamic.Coherent thoughtsWe?re not claiming that SED is the final word. But it does offer a coherent picture of microphysical processes based on physical fields and forces. Importantly, it doesn?t abandon the quantum formalism but rather reframes it as an effective theory ? a statistical summary of deeper dynamics. Such a perspective enables us to maintain the successes of quantum mechanics while seeking to explain its origins.For us, SED highlights that quantum phenomena can be reconciled with concepts central to the rest of physics, such as realism, causality and locality. It also shows that alternative approaches can yield testable predictions and provide new insights into long-standing puzzles. One phenomenon lying beyond current quantum formalism that we could now test, thanks to progress in experimental physics, is the predicted violation of Heisenberg?s inequalities over very short time periods.As quantum science continues to advance, we must not lose sight of its conceptual foundations. Indeed, a coherent, causally grounded understanding of quantum mechanics is not a distraction from technological progress but a prerequisite for its full realization. By turning our attention once again to the foundations of the theory, we may finally complete the edifice that began to rise a century ago.The centenary of quantum mechanics should be a time not just for celebration but critical reflection too.Ana Mar?a Cetto and Luis de la Pe?a are at the Institute of Physics, National Autonomous University of Mexico, e-mail ana@fisica.unam.mx