Session SS02: V: Physics Education: General

Understanding electromagnetism by reviewing the fundamental concepts.

The description of regional hybrid electromagnetics courses implemented during the pandemic are described. Exercises and books that are frequently not contextualized and produced for different audiences from the ones where they are used are prioritized in traditional curriculum.This provides a learning challenge for pupils, frustrating them and leading them to misunderstand the fundamental principles of Physics.

By returning to core concepts and original lectures from scientists like Coulomb, Faraday, and others, the basic curriculum are reviewed. Students are exposed to fundamental concepts, and in order to improve their comprehension and add new skills to the traditional curricula, they are asked to plan, design, and construct their own observational prototypes. 

At Universidad de San Carlos de Guatemala, the course has been offered in a hybrid and virtual format, while at Universidad de Guanajuato, it has been introduced in a virtual and face-to-face format. More than 400 youngsters took part in the courses's activities over the last 3 years. They demonstrate improved academic performance, a deeper comprehension of physical processes, and a variety of skill sets that help students succeed in college.

Also, as a result of this methodology, over 69 original prototypes were displayed in the Electroweek exhibit at Universidad de Guanajuato last year, led by Julián Félix. For the students to communicate and socialize their conclusions, this presentation also included a metaverse implementation.   

Single and double touch mode capacitive pressure/force sensing technique and approach

The cantilevers and diaphragms are extensively explored mechanical elements to design and fabricate normal mode capacitive pressure sensors. However, monitoring large pressure ranges and obtaining linearized capacitance change response w.r.t pressure is quite challenging. Therefore, in order to investigate and solve the problem, single-touch and double-touch mode capacitive sensing techniques are explored. The affordable materials such as aluminium-coated polyimide foil, double sided tape, polyimide tape and posted paper are utilised to fabricate the sensors. The experimental characterisation of sensors is performed using developed air-pressure set-up which is experimentally calibrated using commercially available (MS5803-14BA) micro-pressure sensors. The CO₂ Laser (Universal Laser Systems PLS6.75) is utilised to cut the diaphragms, double-sided and polyimide tape. The Keithley Semiconductor Characterization System (Model-4200 SCS) is used to perform capacitance measurements for characterizing the sensor. The fabricated single-touch mode capacitive pressure sensor shows linear response for 10-40 kPa pressure range, whereas double-touch mode capacitive pressure sensor shows linear response of 14.24-54.9 kPa.

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No Catch-22 for Fuzzy Dark Matter: testing substructure counts and core sizes via high resolution cosmological simulations

Fuzzy Dark Matter (FDM) has recently emerged as an interesting alternative model to the standard Cold Dark Matter (CDM). In this model, dark matter consists of very light bosonic particles with quantum mechanical effects on galactic scales. Since the small-scale behaviour of FDM is completely determined by the mass of the FDM particle, constraining the FDM axion mass remains a crucial test that would allow FDM to be verified or potentially excluded by existing observations. Using the N-body code AX-GADGET, we perform cosmological simulations of FDM that fully model the dynamical effects of the quantum potential throughout cosmic evolution. Through the analysis of FDM volume and high-resolution zoom-in simulations of different FDM particle masses (m_χ ∼ 10⁻²³ − 10⁻²¹ eV), we study how FDM impacts the abundance of substructure and the inner density profiles of dark matter subhalos, respectively. For the first time, using our FDM volume simulations, we provide a fitting formula for the FDM-to-CDM subhalo mass function ratio as a function of the FDM axion mass. Through comparison of our simulation results with observational inferences of the low-mass end of the subhalo mass function and the density profiles of dwarf galaxies surrounding the Milky Way, we will then place a constraint on the FDM axion mass.   

Study of properties of b-jets in the interactions of Pb + Pb at the energy √sNN = 5.02 TeV

Heavy-ion collisions at ultrarrelativistic speeds are performed due to their ability to form QGP. The creation of this primordial matter not tightly bound into hadrons, provides a useful insight on the properties of matter. The aim of this work is to present a software developed to study  the jet-quenching of b-jets in heavy-ion collisions utilising Monte Carlo simulations of the ATLAS detector. This software validates that the simulations generated using Pythia 8.2 with parton distribution functions (PDFs) NNPDF23LO and GEANT 4, has the correct data contents and prepares an event display visualising  the b-jets, c-jets and l-jets. Finally, comparisons between the behavior of b- and c-jets respective to l-jets are shown and discussed.

    

I-Love-Q in Einstein-aether theory

Although local Lorentz invariance is a staple of General Relativity (GR), there are several reasons to believe it may not hold in a more advanced theory of gravity, such as quantum gravity. A way to investigate and test Lorentz symmetry violation is to study it within modifications to GR. One such modified theory is Einstein-aether theory, which breaks Lorentz symmetry by introducing a dynamical vector field called the aether. The aether is timelike and points out a preferred time direction at each point in space. Einstein-aether theory has four coupling constants that characterize deviations from GR and which must be determined, or constrained, by experimental observations. Although three of the four parameters have been constrained by various empirical observations and stability requirements, one, called cω, remains unconstrained. The goal of this work is to see if it is feasible to use neutron star observables to constrain cω. Specifically, we aim to see if a constraint can be derived from the I-Love-Q universal relations, which are relations between the neutron star moment of inertia (I), tidal Love number (Love), and quadrupole moment (Q). These relations are useful for utilizing neutron star observables because they are insensitive to uncertainties in the neutron star equation-of-state. We find that the I-Love-Q relations in Einstein-aether theory are insensitive to cω and that they are close to the relations in GR. These results indicate that to constrain the theory with neutron stars, it is necessary to investigate other relations and observables, such as stellar oscillation frequencies.   

Analysis of Energies and Nodes through a First-Order Schrodinger Equation

For most potentials, the Schrödinger equation does not admit exact solutions. However, some exact bounds are possible. We transform the one-dimensional time-independent Schrodinger equation into a well-behaved first order differential equation. Many properties of energy eigenfunctions are seen geometrically through the direction field of the transformed Schrodinger equation. Using quasi-eigenfunctions, we prove a generalization of the node theorem which yields the number of nodes of the quasi-eigenfunction based on the position of the quasi-eigenfunction's energy in the system's energy spectrum. We use these results to prove bounds on the energies of perturbed potentials. Unlike standard perturbation theory results, this treatment remains valid even for large perturbations, allowing us to address problems where perturbation theory is not applicable. This work provides a novel method to analyze quantum mechanics problems that is complementary to well established perturbation theory, variational principle, and WKB techniques.   

Normalizing Flows for Multimodal and Extended-Mode Lattice Field Theories

Probability distributions are ubiquitous in physics and form the basis for our descriptions of quantum and statistical systems. For example, the field of lattice quantum field theory examines physical theories in the strong coupling regime where perturbative methods cannot be applied, conventionally requiring calculations that involve numerically intensive Monte Carlo sampling of field configurations. Normalizing flows have emerged as a promising class of generative machine learning models that learn and exactly sample from complicated target distributions. Here, we discuss the application of normalizing flows as samplers for lattice quantum field theories. In example applications to toy lattice field theories, we incorporate physical constraints such as symmetry into the flow architecture, overcoming the issue of partial mode structure undersampling often seen in normalizing flows applied to theories with spontaneous symmetry breaking. The resulting generative models are shown to capture the full mode structure of the target distribution.