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We present an intermediate-level course on sustainable physics, which combines lectures and student projects. Sustainable physics concepts are progressively introduced through both a global and a specialized perspective: climate change and building design. The lectures and hands-on activities on both topics show how they share common concepts and provide complementary points of view. Climate change mitigation and adaptation are touched on via student group projects, where they are asked to tackle a specific question of their choosing via reviews of the literature, modeling, or experiments. [ABSTRACT FROM AUTHOR]

The October 2024 issue of the American Journal of Physics features a variety of articles covering different topics in physics. These include a lecture on pursuing excellence in physics, a resource letter on the synthesis of elements in stars, a study on the physics of "everesting" on a bicycle, an exploration of degrees of freedom in complex systems, an investigation into the elongation of ferrofluid droplets near magnets, an analysis of heat engines with finite reservoirs, a discussion on Heisenberg's reactor theory and the development of the atomic bomb, a simplified relativity experiment, a vector theory of gravitational waves, an experiment on two-particle interference, a numerical simulation project in micromagnetics, a model on opinion dynamics and cognitive biases, a flipped electronics lab for learning upper division electronics at home, and a review of the book "A Standard Model Workbook." These articles cover a range of topics and can be useful for researchers and students interested in various areas of physics. [Extracted from the article]

The given document is a summary of the August 2024 issue of the American Journal of Physics. It includes letters to the editor discussing topics such as the discovery of angular momentum of the photon and the dynamics of a bouncing capsule. The issue also features award citations from the 2024 AAPT summer meeting, as well as articles on various physics topics including the transition from bouncing to rolling on a horizontal surface, tractor magnets, magnetostatic field lines, diffraction patterns, Rutherford scattering, entanglement, ultrafast timescales, Landau levels, and the rod and slit paradox. Additionally, there is a comment on the linearity of the generalized Lorentz transformation and a review of the book "Is Einstein Still Right? Black Holes, Gravitational Waves, and the Quest to Verify." [Extracted from the article]

Electronic properties of low dimensional superconductors are determined by many-body-effects. This physics has been studied traditionally with superconducting thin films and in recent times with two-dimensional electron gases (2DEGs) at oxide interfaces. In this work, we show that a superconducting 2DEG can be generated by simply evaporating a thin layer of metallic Al under ultrahigh vacuum on a SrTiO 3 crystal, whereby Al oxidizes into amorphous insulating alumina, doping the SrTiO 3 surface with oxygen vacancies. The superconducting critical temperature of the resulting 2DEG is found to be tunable with a gate voltage with a maximum value of 360 mK. A gate-induced switching between superconducting and resistive states is demonstrated. Compared to conventionally-used pulsed-laser deposition, our work simplifies to a large extent the process of fabricating oxide-based superconducting 2DEGs. It will make such systems accessible to a broad range of experimental techniques useful to understand low-dimensional phase transitions and complex many-body-phenomena in electronic systems. [ABSTRACT FROM AUTHOR]

The American Journal of Physics has published its July 2024 issue, which includes a variety of articles on different topics in physics. Some of the articles featured in this issue include a new derivation of the Earth's eccentricity using mathematical tools commonly used in electrostatics, an exploration of counterclockwise thermodynamic cycles and their practical applications, and a study on the gas-liquid transition using the Berthelot model. Other articles cover topics such as visualizing qubits in quantum information, investigating systematic uncertainty in the e/m experiment, and teaching students about spin coating in semiconductor processing. The issue also includes a note on using free software to calculate scattering cross sections. These articles provide valuable insights and information for students and researchers in various fields of physics. [Extracted from the article]

The American Journal of Physics has published its June 2024 issue, which includes a variety of articles on topics such as orbital mechanics with the Global Positioning System, Lagrange points, dynamics of a bouncing capsule, Bell's dynamical route to special relativity, determining the difference between local acceleration and local gravity, the state principle of classical thermodynamics, a new unit of measurement for introductory physics lab, linewidth measurement of external cavity laser, quantum versus classical quenches, mutual inductance between an infinite solenoid and a surrounding loop, and the "contact" hyperfine interaction. The articles cover a range of subjects and are suitable for different levels of study, from introductory to graduate-level courses. [Extracted from the article]

The May 2024 issue of the American Journal of Physics features a variety of articles covering topics in physics. These include letters to the editor, a tool for developing inclusive physics textbooks, labor-based grading practices, a modern interpretation of Newton's theorem of revolving orbits, the effects of general relativistic post-Newtonian approximations, seldom-used theorems of vector calculus, screening in solid state physics, the hyperfine interaction in hydrogen, the Born rule in quantum mechanics, statistical physics of frictional grains, an in-fiber Mach-Zehnder strain sensor, an Arduino cavity controller for LIGO analogy lab, a resolution of the trolley paradox, an unorthodox physical solution to a classic puzzle, and a book review on solar power finance. These articles cover a range of topics and can be useful for researchers and students in various physics disciplines. [Extracted from the article]

The April 2024 issue of the American Journal of Physics features a variety of articles covering topics in physics. One article provides an overview of dark matter, discussing its historical evidence, possible candidates, and detection techniques. Another article explores relativistic acceleration in noninertial frames, analyzing scenarios with differences in proper time elapsed and spacetime events. A third article discusses a method for calculating wavefunctions in quantum mechanics without differential equations. Other articles cover topics such as stochastic trajectories, Brownian motion, first passage time distribution, Young's double-slit interference, and using Minecraft for learning digital electronics. These articles offer valuable insights and experiments for students and researchers in the field of physics. [Extracted from the article]

The American Journal of Physics has published its February 2024 issue, which includes a variety of articles on different physics topics. These articles cover subjects such as the physics of firefighting devices, measuring dispersion relationships for capillary waves, studying Coriolis acceleration and critical slowing-down, analyzing mechanical analogies to photonic and phononic crystals, exploring the modes of fractal drums, simulating non-adiabatic quantum dynamics and photo-excitation processes, deriving Wien's complete displacement law of blackbody radiation, resolving the Ehrenfest paradox, constructing a low-cost spectrometer for student labs, observing the Tyndall effect using an Arduino, photographing a meter stick moving at relativistic speeds, and understanding surface charge and current densities at material boundaries. These articles provide valuable information for undergraduate physics students and instructors. [Extracted from the article]

The American Journal of Physics has published its December 2023 issue, which includes a variety of articles on physics topics. Some of the articles featured in this issue include a study on the effectiveness of daily physics quizzes in improving long-term knowledge retention, an exploration of the mathematical connections between pendulum waves and Thomae's function, a novel approach to teaching rotational physics using bivectors, and an examination of the applicability of the equipartition theorem in thermal physics. Other articles cover topics such as metastable states in quantum systems, mirages, pandemic modeling, molecular spectroscopy, and building a barcode scanner. The issue also includes a comment on Newton's shell-point equivalency theorem and a reprint of a paper from the previous month's issue on S-matrices in quantum systems. Additionally, the journal lists several books that have been received for review, including titles on the Einsteinian revolution, the Higgs boson, special relativity, and the history of experimental science. [Extracted from the article]

This paper describes an undergraduate-level experiment where the induced voltage created by dropping a disk magnet through a coil wrapped around a plastic pipe is recorded and compared to an analytic model based on treating the magnet as a dipole. This paper presents a new way to study this interaction in two dimensions by mounting dipole magnets inside plastic shells and floating them on a water surface to create a compelling demonstration or student laboratory. Infinite-fold energy degeneracy in 2D square lattices of magnetic spheres Kyongwan Kim B 91 b (8), p. 603 https://doi.org/10.1119/5.0121937 Anyone who has played with magnets knows that when they are grouped together, their dipole interactions fix their orientations relative to each other. [Extracted from the article]

Return to that time with the author, as he describes these instruments and fondly recalls the joys and challenges of using them as a student in the 1950s, and later as a young physics professor. These brief summaries are designed to help readers easily see which articles will be most valuable to them. The E&M lab may have disappeared long ago, replaced by courses in electronics and computing, but have we lost something valuable in the transition?. [Extracted from the article]

This setup is a useful tool for teaching advanced physics students about the phase-sensitive detection experimental technique, and it can be a viable low-cost alternative to commercial lock-in amplifiers for certain research situations. This paper shows how the more general Bohr-Sommerfeld planetary orbits can also be understood using de Broglie waves, providing a link between quantum and classical physics that may help students better understand both aspects of physics. The simplicity and cost-efficient design of the setup make it an excellent avenue for developing student understanding of confocal microscopy and the physics underlying this widely used experimental technique. [Extracted from the article]

Projectile motion with quadratic drag John L. Bradshaw B 91 b (4), p. 258 https://doi.org/10.1119/5.0095643 Projectile motion with air resistance is a staple topic of dynamics courses. An easier-to-align Hong-Ou-Mandel interference demonstration Nicholas S. DiBrita and Enrique J. Galvez B 91 b (4), p. 307 https://doi.org/10.1119/5.0119906 The Hong-Ou-Mandel experiment demonstrates fundamental quantum-mechanical concepts such as wavefunction symmetry and particle indistinguishability. The simple computational model can form the basis of student problems and projects and could also be used in a non-calculus-based course for students interested in biology and medicine. [Extracted from the article]

A wave packet approach to resonant scattering A. M. Michalik and F. Marsiglio B 91 b (2), p. 102 https://doi.org/10.1119/5.0106701 Most treatments of scattering theory in upper-level quantum mechanics classes use time-independent plane-wave formulations, but this limits qualitative understanding of the details of the scattering process, particularly in cases of resonant scattering where constructive interference leads to the complete passage of an incoming wave through an array of barriers. This article reviews some other common ways to introduce the Schrödinger equation and develops its own pedagogical approach (which has its roots in the foundations of quantum mechanics) based on classical Hamilton-Jacobi theory. "A call to action": Schrödinger's representation of quantum mechanics via Hamilton's principl... Michele Marrocco B 91 b (2), p. 110 https://doi.org/10.1119/5.0083015 Quantum mechanics courses often present the Schrödinger equation as a fundamental postulate. [Extracted from the article]

Letters to the editor Kirk T. McDonald, B 90 b (11), p. 807 https://doi.org/10.1119/5.0124266 Olivier Pujol, B 90 b (11), p. 807 https://doi.org/10.1119/5.0124948 Kirk T. McDonald, B 90 b (11), p. 808 https://doi.org/10.1119/50124271 Rod Cross, B 90 b (11), p. 808 https://doi.org/10.119/50127740 Please enjoy these letters-to-the-editor and consider writing one yourself. The authors describe an undergraduate modern physics distance lab course, implemented during the COVID-19 pandemic, where students grasp a better understanding of the ideal gas law and of the Drude model by simulating microscopic behaviors with macroscopic objects. The work described here offers an accessible project-the surface plasmon resonance phenomenon-for the undergraduate instructional laboratory. [Extracted from the article]

10.1119/1.5008862.1 Friction is a complex phenomenon that is of paramount importance in everyday life. We present an easy-to-build and inexpensive experiment illustrating Coulomb's law of kinetic friction. The so-called friction, or Timoshenko, oscillator consists of a plate set into periodic motion through the competition between gravity and friction on its rotating supports. The period of such an oscillator gives a measurement of the coefficient of kinetic friction μk between the plate and the supports. Our prototype is mainly composed of a motor, LEGO blocks, and a low-cost microcontroller, but despite its simplicity, the results obtained are in good agreement with values of μk found in the literature (enhanced online). [ABSTRACT FROM AUTHOR]

Waving arms around to teach quantum mechanics Kelby T. Hahn and Elizabeth Gire B 90 b (10), p. 778 https://doi.org/10.1119/5.0073946 Building a representation of quantum states is notoriously difficult for students starting quantum mechanics. Stereographic projection to and from the Bloch sphere: Visualizing solutions of the Bloch equ... David J. Siminovitch B 90 b (10), p. 755 https://doi.org/10.1119/5.0088987 Stereographic projection is an elegant analysis technique that receives little attention in undergraduate physics. It explains how students can impersonate quantum spin eigenstates with their arm, gaining a deeper physical understanding of relative phases, decomposition in an eigenstate basis, and the time-evolution of quantum states. [Extracted from the article]

This paper shows how to use a smartphone camera as an optics lab at a wide range of levels. This art technique can become a nice student project or can be inserted into an inexpensive undergraduate optics lab. These experiments could be implemented in an optics or acoustics lab or in a more general advanced laboratory course. [Extracted from the article]

Then, as an added bonus, the authors show how the same mathematics yields the demagnetization factor for a prolate spheroid, a result that is used widely in magnetization measurements but is seldom derived because - until now - the known mathematical approaches were extremely challenging. The authors here take the physics analysis a step further and consider the rigidity of the string to calculate the characteristic frequencies of plucked guitar strings. This material is appropriate for an undergraduate class on wave physics, building a connection with condensed matter physics. [Extracted from the article]

Gravitoelectromagnetism: Removing action-at-a-distance in teaching physics Friedrich Herrmann and Michael Pohlig B 90 b (6), p. 410 https://doi.org/10.1119/10.0009888 Unless one invokes general relativity, gravitation is still taught mostly in its Newtonian action-at-a-distance formulation. Heaviside's theory was analogous to Maxwell's equations and the Poynting flux theorem, but it was not widely adopted because many of the effects it describes are small and the later emergence of general relativity seemed to make such a theory of gravitation unnecessary. This paper shows how these goals can be extended into the university teaching laboratory, giving an example of their implementation in a life sciences laboratory course. [Extracted from the article]

Finally, the authors review a number of signal-processing techniques, employing their apparatus as an "optical microphone" to demonstrate each technique's effectiveness in recovering speech and music in noisy environments. The apparatus can be used as a demonstration of GW detection for non-specialists, or, with an added emphasis on signal processing, in physics, engineering, or cross-disciplinary classes. They then introduce the Viterbi algorithm, a signal processing technique used by GW observatories to detect signals that drift slowly in frequency, and demonstrate its effectiveness using their tabletop apparatus. [Extracted from the article]

A new microscopic look into pressure fields and local buoyancy S. Meneses João, J. P. Santos Pires, and J. M. Viana Parente Lopes B 90 b (3), p. 179 https://doi.org/10.1119/5.0060479 Local pressure fields are integral to understanding buoyancy, atmospheric phenomena, and other systems, but standard statistical mechanics approaches only derive the global thermodynamic pressure from the microscopic description of the system. The paper can be useful in undergraduate mechanics class or as an example of the use of Laplace transform for system control, but you'll also want to read it just to learn about this example of physics in action. Teachers of advanced undergraduate or graduate statistical mechanics may find this inspiring material for projects or problem sets. [Extracted from the article]

Velocity reciprocity and the relativity principle Patrick Moylan B 90 b (2), p. 126 https://doi.org/10.1119/10.0009219 Velocity reciprocity is the property that pairs of inertial reference frames will measure each other to have equal and opposite relative velocities. This paper analyses the group-theoretic foundations of relativity theory to explore what additional assumptions must be made for velocity reciprocity to hold, and also explores the misconception that velocity reciprocity follows from the relativity of motion principle. Exploring complex pattern formation with convolutional neural networks Christian Scholz and Sandy Scholz B 90 b (2), p. 141 https://doi.org/10.1119/5.0065458 Machine learning is becoming more and more important in the analysis of data in many fields including physics. [Extracted from the article]

On the ubiquity of classical harmonic oscillators and a universal equation for the natural fr... J. J. Bissell B 89 b (12), p. 1094 https://doi.org/10.1119/10.0005948 Simple harmonic motion re-appears throughout physics. Resource Letter BP-1: Biological physics Raghuveer Parthasarathy B 89 b (12), p. 1071 https://doi.org/10.1119/5.0060279 Biological physics includes a huge breadth of research: The annual meeting of the Biophysical Society typically attracts more than 6000 researchers. Using smartphone photographs of the Moon to acquaint students with non-Euclidean geometry Hugo Caerols, Rodrigo A. Carrasco, and Felipe A. Asenjo B 89 b (12), p. 1079 https://doi.org/10.1119/10.0006156 Concepts of non-Euclidean geometry can be challenging for beginning students. [Extracted from the article]

This paper works out an algorithm in a way that provides an interesting example for an intermediate-level mechanics or computational physics course. By invoking the reflection property of the ellipse, calculus is avoided entirely, making this approach ideal for use in introductory physics and astronomy courses. Based on retention in STEM programs, grades in the module and in subsequent STEM courses, and survey/interview data, the course achieved its goals admirably. [Extracted from the article]

Drone-drone collisions over New York City via the kinetic theory of gases I Edward W. Walbridge i B 89 b (10), p. 930 https://doi.org/10.1119/10.0005035 If the predictions made by companies, such as Amazon, hold true, more than 50% of parcel deliveries will be made by drone aircraft within the present decade. In this article, the author uses kinetic theory to estimate the surprisingly high collision rate between hypothetical "dumb" drones, which have no collision avoidance capability, and discusses the required reliability of such systems to ensure safe operation. These brief summaries are designed to help readers easily see which articles will be most valuable to them. [Extracted from the article]

Using a proper cooling procedure, a controllable amount of nonmagnetic structural disorder can be introduced at low temperature in (TMTSF)24. Here we performed simultaneous measurements of transport and magnetic properties of (TMTSF)24 in its normal and superconducting states, while finely covering three orders of magnitude of the cooling rate around the anion ordering temperature. Our result reveals, with increasing density of disorder, the existence of a crossover between homogeneous defect-controlled d-wave superconductivity and granular superconductivity. At slow cooling rates, with small amount of disorder, the evolution of superconducting properties is well described with the Abrikosov-Gorkov theory, providing further confirmation of non-s-wave pairing in this compound. In contrast, at fast cooling rates, zero resistance and diamagnetic shielding are achieved through a randomly distributed network of superconducting puddles embedded in a normal conducting background and interconnected by proximity effect coupling. The temperature dependence of the ac complex susceptibility reveals features typical for a network of granular superconductors. This makes (TMTSF)24 a model system for granular superconductivity where the grain size and their concentration are tunable within the same sample. [ABSTRACT FROM AUTHOR]

We report on the development of scintillating bolometers based on lithium molybdate crystals that contain molybdenum that has depleted into the double-β active isotope 100Mo (Li2100deplMoO4). We used two Li2100deplMoO4 cubic samples, each of which consisted of 45-millimeter sides and had a mass of 0.28 kg; these samples were produced following the purification and crystallization protocols developed for double-β search experiments with 100Mo-enriched Li2MoO4 crystals. Bolometric Ge detectors were utilized to register the scintillation photons that were emitted by the Li2100deplMoO4 crystal scintillators. The measurements were performed in the CROSS cryogenic set-up at the Canfranc Underground Laboratory (Spain). We observed that the Li2100deplMoO4 scintillating bolometers were characterized by an excellent spectrometric performance (∼3-6 keV of FWHM at 0.24-2.6 MeV γs), moderate scintillation signal (∼0.3-0.6 keV/MeV scintillation-to-heat energy ratio, depending on the light collection conditions), and high radiopurity (228Th and 226Ra activities are below a few µBq/kg), which is comparable with the best reported results of low-temperature detectors that are based on Li2MoO4 using natural or 100Mo-enriched molybdenum content. The prospects of Li2100deplMoO4 bolometers for use in rare-event search experiments are briefly discussed.