arXiv subjects

David A. Miranda

Publications and source records attributed to David A. Miranda.

4 recordsLinked to original sources

arXiv2026

Three-Electrode TiO2 + rGO Cells: Classical Controls and Interpretation within a Quantum-Discord Framework

In three-electrode electrochemical impedance spectroscopy (EIS), the impedance/capacitance response of the working electrode (WE) is measured relative to the reference electrode (RE), whereas the current required by potentiostatic control flows between the WE and the counter electrode (CE). Under classical three-electrode operation, the measured WE-RE response should therefore be independent of the properties of the electrode used as the CE, provided that conventional electrochemical and instrumental artifacts are negligible. Here, we test this expectation in cells containing nanostructured electrodes TiO2 + rGO and examine the results within a framework motivated by quantum discord to describe effective interelectrode correlations. We used dummy-cell measurements, a two-electrode bar-bar control, comparisons between Pt and bar CEs, a dummy circuit introduced into the CE branch, and CE ensemble comparisons to distinguish additive circuit behavior from CE-dependent behavior specific to the three-electrode configuration. In these experiments, the measured three-electrode capacitance response depends on CE, an effect that is not reproduced by the dummy-circuit controls examined. These findings identify a macroscopic CE-dependent capacitance response that departs from the tested classical expectation and is compatible with an effective interelectrode-correlation framework motivated by quantum discord, although the capacitance evidence alone does not constitute a direct measurement of quantum discord.

physics.chem-ph↗

arXiv2024

Quantum Electrodynamics in an Electrolyte Medium Driving Entanglement Between Graphene Sheets

The quantum entanglement phenomenon was demonstrated to operate on a bipartite entangled system composed of two single layers of graphene embedded in an electrolytic medium (which did not permit the transport of electrons) and subjected to an external time-dependent electric perturbation driven by a potentiostat equipped with a frequency response analyser. Time-dependent perturbation-mediating entanglement was hypothesised because of the equivalent quantum resistive-capacitive circuit frequency of each single-layer graphene system that obeys quantum electrodynamics principles. \textit{De facto}, quantum electrodynamics, associated with the massless fermionic characteristics in graphene sheets, was observed at room temperature and electrolyte medium under a time-dependent modulation, and the entanglement between the two sheets is consistent with a Hilbertian subspace mathematical examination of the phenomenon. Remarkably, this experiment, among numerous other quantum electrochemical experiments conducted by this research group that follow quantum electrodynamics principles, highlights the generality of the methodology for studying entanglement phenomena, leading to alternative methods for investigating Weyl semi-metal structures and designing room-temperature quantum applications.

physics.gen-ph↗

arXiv2024

Frequency Domain Analysis of Dynamic Light Scattering in the Breast Cancer Risk Screening: A Proof of Concept

We present a proof of concept for screening breast cancer risk by detecting biochemical alterations in breast tissue using a noninvasive and low-cost technique that uses dynamic light scattering for field effect detection by spectral analysis (FEDSA). This technique consists of a light source that illuminates the tissue, and the backscattering light by the tissue is acquired by two detectors; next, the signal goes to the acquisition system, and then with the designed software the power spectra are calculated. The power spectra contain the frequency contribution related to the size of tissue compounds. These frequency contributions change with the biochemical alterations that are amplified by the field effect on tissue. This implies that the initial alterations in the breast are not local. To test FEDSA, two experiments were performed: the first was with Alumina particles grouped in average sizes of $60-300nm$, $100 - 400nm$ and polystyrene nanoparticles in suspension ($315nm$). The second was with 24 women, 17 of whom had normal tissue and 7 abnormal; abnormalities were previously detected by mammogram or ultrasound. Power spectra were obtained for all particles, in agreement with the particle size. In the case of normal and abnormal tissues, the power spectra of the tissues show differences in the shape of the spectra in the range of 1 to 160 kHz. ROC analysis suggests a possible good sensitivity (87.5\%) and specificity (68.1\%) in classifying breast tissue conditions. Statistical analysis with $p<0.05$ revealed significant differences in two quadrants of the breast, the upper inner right and the upper outer left, which were consistent with previous diagnoses by mammography and ultrasound. This proof of concept opens the possibility of implementing and improving FEDSA in the detection of early anomalies in the breast as a low-cost technique that does not use ionizing radiation.

physics.med-ph↗

arXiv2024

Física Estadística: teoría, ejemplos trabajados, modelos y simulaciones

In this book, we study Statistical Physics under conditions of thermodynamic equilibrium, starting from the definition of statistical ensembles. The book is divided into five chapters: First, a brief introduction to statistical methods. Second, the statistical description of isolated systems, corresponding to microcanonical ensembles. Third, the statistical description of systems in contact with a heat reservoir at a constant temperature T, known as the canonical ensemble. Fourth, the description of systems in contact with a heat reservoir at temperature T and with a constant chemical potential μ; the grand canonical ensemble. And finally, quantum statistics. In each chapter, a theoretical description, worked examples, links to simulations (see GitHub repository: https://github.com/davidalejandromiranda/StatisticalPhysics) and discussions on recent scientific reports will be presented so readers can complement their studies.

cond-mat.stat-mech↗