Physical Sciences and Mathematics Commons^™

The Effects Of Temperature, Humidity, And Barometric Pressure On Short-Sprint Race Times, Jonas R. Mureika

Jonas Mureika

A numerical model of 100 m and 200 m world class sprinting performances is modified using standard hydrodynamic principles to include effects of air temperature, pressure, and humidity levels on aerodynamic drag. The magnitude of the effects are found to be dependent on wind speed. This implies that differing atmospheric conditions can yield slightly different corrections for the same wind gauge reading. In the absence of wind, temperature is found to induce the largest variation in times (0.01 s per 10◦C increment in the 100 m), while relative humidity contributes the least (under 0.01 s for all realistic conditions for …

Multifractal Structure In Nonrepresentational Art, Jonas R. Mureika, C. C. Dyer, G. C. Cupchik

Jonas Mureika

Multifractal analysis techniques are applied to patterns in several abstract expressionist artworks, painted by various artists. The analysis is carried out on two distinct types of structures: the physical patterns formed by a specific color (“blobs”) and patterns formed by the luminance gradient between adjacent colors (“edges”). It is found that the multifractal analysis method applied to “blobs” cannot distinguish between artists of the same movement, yielding a multifractal spectrum of dimensions between about 1.5 and 1.8. The method can distinguish between different types of images, however, as demonstrated by studying a radically different type of art. The data suggest …

Does Entropic Gravity Bound The Masses Of The Photon And Graviton?, Jonas R. Mureika, R. B. Mann

Jonas Mureika

If the information transfer between test particle and holographic screen in entropic gravity respects both the uncertainty principle and causality, a lower limit on the number of bits in the universe relative to its mass may be derived. Furthermore, these limits indicate particles that putatively travel at the speed of light -- the photon and/or graviton -- have a non-zero mass m≥10−68 kg. This result is found to be in excellent agreement with current experimental mass bounds on the graviton and photon, suggesting that entropic gravity may be the result of a (recent) softly-broken local symmetry. Stronger bounds emerge from …

Self-Completeness And The Generalized Uncertainty Principle, Maximiliano Isi, Jonas Mureika, Piero Nicolini

Jonas Mureika

The generalized uncertainty principle discloses a self-complete characteristic of gravity, namely the possibility of masking any curvature singularity behind an event horizon as a result of matter compression at the Planck scale. In this paper we extend the above reasoning in order to overcome some current limitations to the framework, including the absence of a consistent metric describing such Planck-scale black holes. We implement a minimum-size black hole in terms of the extremal configuration of a neutral non-rotating metric, which we derived by mimicking the effects of the generalized uncertainty principle via a short scale modified version of Einstein gravity. …

Primordial Black Hole Evaporation And Spontaneous Dimensional Reduction, Jonas R. Mureika

Jonas Mureika

Several different approaches to quantum gravity suggest the effective dimension of spacetime reduces from four to two near the Planck scale. In light of such evidence, this Letter re-examines the thermodynamics of primordial black holes (PBHs) in specific lower-dimensional gravitational models. Unlike in four dimensions, (1 + 1)-D black holes radiate with power P ∼ M²_BH, while it is known no (2+1)-D (BTZ) black holes can exist in a non-anti-de Sitter universe. This has important relevance to the PBH population size and distribution, and consequently on cosmological evolution scenarios. The number of PBHs that have evaporated to …

Unparticle-Enhanced Black Holes At The Lhc, Jonas R. Mureika

Jonas Mureika

Based on the idea that tensor unparticles can enhance the gravitational interactions between standard model particles, potential black hole formation in high energy collisions is examined. Modifications to the horizon radius rH are derived, and the corresponding geometric cross-sections of such objects are calculated. It is shown that rH increases dramatically to the electroweak scale for masses MBH∼1–10 TeV, yielding a geometric cross-section σBH=πr2H on the order of ⩽50 pb. This suggests that unparticle physics provides a mechanism for black hole formation in future accelerators, without the requirement of extra spatial dimensions.

Gravitationally Induced Quantum Superposition Reduction With Large Extra Dimensions, Jonas R. Mureika

Jonas Mureika

A gravity-driven mechanism (``objective reduction'') proposed to explain quantum state reduction is analyzed in light of the possible existence of large extra dimensions in the ADD scenario. By calculating order-of-magnitude estimates for nucleon superpositions, it is shown that if the mechanism at question is correct, constraints may be placed on the number and size of extra dimensions. Hence, measurement of superposition collapse times ({\it e.g.} through diffraction or reflection experiments) could represent a new probe of extra dimensions. The influence of a time-dependent gravitational constant on the gravity-driven collapse scheme with and without the presence of extra dimensions is also …

Sub-Planckian Black Holes And The Generalized Uncertainty Principle, Bernard Carr, Jonas R. Mureika, Piero Nicolini

Jonas Mureika

The Black Hole Uncertainty Principle correspondence suggests that there could exist black holes with mass beneath the Planck scale but radius of order the Compton scale rather than Schwarzschild scale. We present a modified, self-dual Schwarzschild-like metric that reproduces desirable aspects of a variety of disparate models in the sub-Planckian limit, while remaining Schwarzschild in the large mass limit. The self-dual nature of this solution under M ↔ M−1 naturally implies a Generalized Uncertainty Principle with the linear form Δx∼1/Δp+Δp. We also demonstrate a natural dimensional reduction feature, in that the gravitational radius and thermodynamics of sub-Planckian objects resemble that …

Aspects Of Noncommutative (1+1)-Dimensional Black Holes, Jonas R. Mureika, Piero Nicolini

Jonas Mureika

We present a comprehensive analysis of the spacetime structure and thermodynamics of ( 1 + 1 )-dimensional black holes in a noncommutative framework. It is shown that a wider variety of solutions are possible than the commutative case considered previously in the literature. As expected, the introduction of a minimal length √ θ cures singularity pathologies that plague the standard two-dimensional general relativistic case, where the latter solution is recovered at large length scales. Depending on the choice of input parameters (black hole mass M, cosmological constant Λ , etc.), black hole solutions with zero, up to six, horizons are …

Fractal Dimensions In Perceptual Color Space: A Comparison Study Using Jackson Pollock’S Art, Jonas R. Mureika

Jonas Mureika

The fractal dimensions of color-specific paint patterns in various Jackson Pollock paintings are calculated using a filtering process that models perceptual response to color differences (L*a*b* color space). The advantage of the L*a*b* space filtering method over traditional red-green-blue (RGB) spaces is that the former is a perceptually uniform (metric) space, leading to a more consistent definition of “perceptually different” colors. It is determined that the RGB filtering method underestimates the perceived fractal dimension of lighter-colored patterns but not of darker ones, if the same selection criteria is applied to each. Implications of the findings to Fechner’s “principle of …

Constraints On Vector Unparticle Physics From Cosmic Censorship, Jonas R. Mureika

Jonas Mureika

Vector unparticle couplings to standard model fields produce repulsive corrections to gravity. From a general relativistic perspective, this leads to an effective Reissner-Nordstrom-like metric whose "charge" is a function of the unparticle coupling constant λ, and therefore can admit naked singularities. Requiring the system to respect cosmic censorship provides a new method of constraining the value of λ. These limits are extremely loose for stellar-mass black holes, but commensurate with existing bounds for primordial black holes. In the case of theoretical low-mass black holes, the bounds on λ are much stricter than those derived from astrophysical and accelerator phenomenology. Additional …

(1+1)-Dimensional Entropic Gravity, R. B. Mann, Jonas R. Mureika

Jonas Mureika

We consider the formulation of entropic gravity in two spacetime dimensions. The usual gravitational force law is derived even in the absence of area, as normally required by the holographic principle. A special feature of this perspective concerns the nature of temperature and entropy defined at a point. We argue that the constancy of the gravitational force in one spatial dimension implies the information contained at each point in space is an internal degree of freedom on the manifold, and furthermore is a universal constant, contrary to previous assertions that entropic gravity in one spatial dimension is ill-defined. We give …

Detecting Vanishing Dimensions Via Primordial Gravitational Wave Astronomy, Jonas R. Mureika, Dejan Stojkovic

Jonas Mureika

Lower dimensionality at higher energies has manifold theoretical advantages as recently pointed out by Anchordoqui et al. [arXiv:1003.5914]. Moreover, it appears that experimental evidence may already exist for it: A statistically significant planar alignment of events with energies higher than TeV has been observed in some earlier cosmic ray experiments. We propose a robust and independent test for this new paradigm. Since ( 2 + 1 )-dimensional spacetimes have no gravitational degrees of freedom, gravity waves cannot be produced in that epoch. This places a universal maximum frequency at which primordial waves can propagate, marked by the transition between dimensions. …

Could Any Black Holes Be Produced At The Lhc?, Jonas R. Mureika, Piero Nicolini, Euro Spallucci

Jonas Mureika

We introduce analytical quantum gravity modifications of the production cross section for terascale black holes by employing an effective ultraviolet cut off l. We find the new cross sections approach the usual "black disk" form at high energy, while they differ significantly near the fundamental scale from the standard increase with respect to s. We show that the heretofore discontinuous step function used to represent the cross section threshold can realistically be modeled by two functions representing the incoming and final parton states in a high energy collision. The growth of the cross section with collision energy is …

Changes In Severe Thunderstorm Environment Frequency During The 21st Century Caused By Anthropogenically Enhanced Global Radiative Forcing, Robert J. Trapp, Noah S. Diffenbaugh, Harold E. Brooks, Michael E. Baldwin, Eric D. Robinson, Jeremy S. Pal

Jeremy Pal

Severe thunderstorms comprise an extreme class of deep convective clouds and produce high-impact weather such as destructive surface winds, hail, and tornadoes. This study addresses the question of how severe thunderstorm frequency in the United States might change because of enhanced global radiative forcing associated with elevated greenhouse gas concentrations. We use global climate models and a high-resolution regional climate model to examine the larger-scale (or “environmental”) meteorological conditions that foster severe thunderstorm formation. Across this model suite, we find a net increase during the late 21st century in the number of days in which these severe thunderstorm environmental conditions …

Consistency Of Projected Drought Over The Sahel With Changes In The Monsoon Circulation And Extremes In A Regional Climate Model Projections, M. B. Sylla, A. T. Gaye, G. S. Jenkins, Jeremy S. Pal, F. Giorgi

Jeremy Pal

As a step toward an increased understanding of climate change over West Africa, in this paper we analyze the relationship between rainfall changes and monsoon dynamics in high-resolution regional climate model experiments performed using the Regional Climate Model (RegCM3). Multidecadal simulations are carried out for present-day and future climate conditions under increased greenhouse gas forcing driven by the global climate model European Center/Hamburg 5 (ECHAM5). Compared to the present day, the future scenario simulation produces drier conditions over the Sahel and wetter conditions over orographic areas. The Sahel drying is accompanied by a weaker monsoon flow, a southward migration and …

Regional Climate Modeling For The Developing World: The Ictp Regcm3 And Regcnet, Jeremy S. Pal, Filippo Giorgi, Xunqiang Bi, Nellie Elguindi, Fabien Solmon, Xuejie Gao, Sara A. Rauscher, Raquel Francisco, Ashraf Zakey, Jonathan Winter, Moetasim Ashfaq, Faisal S. Syed, Jason L. Bell, Noah S. Diffenbaugh, Jagadish Karmacharya, Abourahamane Konaré, Daniel Martinez, Rosmeri P. Da Rocha, Lisa C. Sloan, Allison L. Steiner

Jeremy Pal

Regional climate models are important research tools available to scientists around the world, including in economically developing nations (EDNs). The Earth Systems Physics (ESP) group of the Abdus Salam International Centre for Theoretical Physics (ICTP) maintains and distributes a state-of-the-science regional climate model called the ICTP Regional Climate Model version 3 (RegCM3), which is currently being used by a large research community for a diverse range of climate-related studies. The RegCM3 is the central, but not only, tool of the ICTP-maintained Regional Climate Research Network (RegCNET) aimed at creating south–south and north–south scientific interactions on the topic of climate and …

Photoelectrochemical Cell Including Ga(SbX)N1-X Semiconductor Electrode, Madhu Menon, Michael Sheetz, Mahendra Kumar Sunkara, Chandrashekhar Pendyala, Swathi Sunkara, Jacek B. Jasinksi

Physics and Astronomy Faculty Patents

The composition of matter comprising Ga(Sb_x)N_1−x where x=0.01 to 0.06 is characterized by a band gap between 2.4 and 1.7 eV. A semiconductor device includes a semiconductor layer of that composition. A photoelectric cell includes that semiconductor device.

Holographic Entanglement Entropy Of A 1 + 1 Dimensional P-Wave Superconductor, Sumit R. Das, Mitsutoshi Fujita, Bom Soo Kim

Physics and Astronomy Faculty Publications

We examine the behavior of entanglement entropy S _A ^EE of a subsystem A in a fully backreacted holographic model of a 1 + 1 dimensional p wave superconductor across the phase transition. For a given temperature, the system goes to a superconducting phase beyond a critical value of the charge density. The entanglement entropy, considered as a function of the charge density at a given temperature, has a cusp at the critical point. In addition, we find that there are three different behaviors in the condensed phase, depending on the subsystem size. For a subsystem size l smaller than …

Three Dimensional View Of The Syk/Ads Duality, Sumit R. Das, Antal Jevicki, Kenta Suzuki

Physics and Astronomy Faculty Publications

We show that the spectrum of the SYK model can be interpreted as that of a 3D scalar coupled to gravity. The scalar has a mass which is at the Breitenholer-Freedman bound of AdS₂, and subject to a delta function potential at the center of the interval along the third direction. This, through Kaluza-Klein procedure on AdS₂ × (S¹)/Z₂, generates the spectrum reproducing the bi-local propagator at strong coupling. Furthermore, the leading 1/J correction calculated in this picture reproduces the known correction to the poles of the SYK propagator, providing …

Automated Software Testing In The Dod: Current Practices And Opportunities For Improvement, Darryl K. Ahner, James Wisnowski, James R. Simpson

Faculty Publications

The concept of automating the testing of software-intensive systems has been around for decades, but the practice of automating testing is scarce in many industries, especially in the government defense sector. A one-year project initiated by the Office of the Secretary of Defense (OSD), Scientific Test and Analysis Techniques Center of Excellence (STAT COE) and sponsored by Navy OPNAV N94 set out to:

• study the degree to which the Department of Defense (DoD) has adopted automated software testing (AST);

• share the best software practices used by industry; and

• develop and distribute an AST implementation guide intended for program management and …

  ---

  Go to article

2017 Fall Engr333 Project Assignment, Matthew K. Heun

ENGR 333

The Fall 2017 ENGR333 project focused on campus energy cost savings.

I asked the students two questions:

• Section A: What would it take for Calvin to save $75k/year on natural gas costs?
• Section B: What would it take for Calvin to save $150k/year on energy costs (mostly electricity) using a new on-site co-gen plant?

Customer

The customer for this project was Phil Beezhold, Director of Calvin’s Physical Plant.

Preventing Neurodegenerative Memory Loss In Hopfield Neuronal Networks Using Cerebral Organoids Or External Microelectronics, M. Morrison, P. D. Maia, J. N. Kutz

Mathematics Faculty Publications

Developing technologies have made significant progress towards linking the brain with brain-machine interfaces (BMIs) which have the potential to aid damaged brains to perform their original motor and cognitive functions. We consider the viability of such devices for mitigating the deleterious effects of memory loss that is induced by neurodegenerative diseases and/or traumatic brain injury (TBI). Our computational study considers the widely used Hopfield network, an autoassociative memory model in which neurons converge to a stable state pattern after receiving an input resembling the given memory. In this study, we connect an auxiliary network of neurons, which models the BMI …

Southern Annular Mode Drives Multicentury Wildfire Activity In Southern South America, Andrés Holz, Juan Paritsis, Ignacio A. Mundo, Thomas T. Veblen, Thomas Kitzberger, Grant J. Williamson, Ezequiel Aráoz, Carlos Bustos-Schindler, Mauro E. González, H. Ricardo Grau, Juan M. Quezada

Geography Faculty Publications and Presentations

The Southern Annular Mode (SAM) is the main driver of climate variability at mid to high latitudes in the Southern Hemisphere, affecting wildfire activity, which in turn pollutes the air and contributes to human health problems and mortality, and potentially provides strong feedback to the climate system through emissions and land cover changes. Here we report the largest Southern Hemisphere network of annually resolved tree ring fire histories, consisting of 1,767 fire-scarred trees from 97 sites (from 22 °S to 54 °S) in southern South America (SAS), to quantify the coupling of SAM and regional wildfire variability using recently created …

Sequential Schemes For Frequentist Estimation Of Properties In Statistical Model Checking, Cyrille Jegourel, Jun Sun, Jin Song Dong

Research Collection School Of Computing and Information Systems

Statistical Model Checking (SMC) is an approximate verification method that overcomes the state space explosion problem for probabilistic systems by Monte Carlo simulations. Simulations might be however costly if many samples are required. It is thus necessary to implement efficient algorithms to reduce the sample size while preserving precision and accuracy. In the literature, some sequential schemes have been provided for the estimation of property occurrence based on predefined confidence and absolute or relative error. Nevertheless, these algorithms remain conservative and may result in huge sample sizes if the required precision standards are demanding. In this article, we compare some …

Sheaf Theoretic Formulation For Consciousness And Qualia And Relationship To The Idealism Of Non-Dual Philosophies, Menas Kafatos, Goro Kato

Mathematics, Physics, and Computer Science Faculty Articles and Research

Questions about the nature of reality, whether Consciousness is the fundamental reality in the universe, and what is Consciousness itself, have no answer in systems that assume an external reality independent of Consciousness. Ultimately, the ontological foundation of such systems is the absolute division of subject and object. We advocate instead what we consider to be an approach that is in agreement with the foundation of quantum reality, which is based on Rāmānuja’s version of Vedanta philosophy and non-dual Kashmir Śaivism. Quantum mechanics opened the door to consciousness, but it cannot account for consciousness. However, the quantum measurement problem implies …

Field Mapping Investigation And Geochemical Analysis Of Volcanic Units Within The Dinner Creek Tuff Eruptive Center, Malheur County, Eastern Oregon, Matthew Cruz

Dissertations and Theses

The Dinner Creek Tuff is a mid-Miocene rhyolitic to dacitic ignimbrite, consisting of four cooling units with ⁴⁰Ar/³⁹Ar ages 16--15 Ma. Previous geologists have suspected that the source of the tuff is located in northwestern Malheur County, eastern Oregon. This broad area is called the Dinner Creek Tuff Eruptive Center.

This thesis summarizes field work, XRF/ICP-MS geochemistry, thin section petrography, and SEM feldspar analysis from the summers of 2015 and 2016. The main purpose of this study is to identify sources for the Dinner Creek Tuff units within the Dinner Creek Tuff Eruptive Center. The secondary purpose …

Fatty Acid Concentration And Phase Transitions Modulate Aβ Aggregation Pathways, Pratip Rana, Dexter Dean, Edward Steen, Ashwin Vaidya, Vijayaraghavan Rangachari, Preetam Ghosh

Faculty Publications

Aggregation of amyloid β (Aβ) peptides is a significant event that underpins Alzheimer disease (AD) pathology. Aβ aggregates, especially the low-molecular weight oligomers, are the primary toxic agents in AD and hence, there is increasing interest in understanding their formation and behavior. Aggregation is a nucleation-dependent process in which the pre-nucleation events are dominated by Aβ homotypic interactions. Dynamic flux and stochasticity during pre-nucleation renders the reactions susceptible to perturbations by other molecules. In this context, we investigate the heterotypic interactions between Aβ and fatty acids (FAs) by two independent tool-sets such as …

Synthesis Of Non-Uniformly Correlated Partially Coherent Sources Using A Deformable Mirror, Milo W. Hyde Iv, Santasri Bose-Pillai, Ryan A. Wood

Faculty Publications

The near real-time synthesis of a non-uniformly correlated partially coherent source using a low-actuator-count deformable mirror is demonstrated. The statistical optics theory underpinning the synthesis method is reviewed. The experimental results of a non-uniformly correlated source are presented and compared to theoretical predictions. A discussion on how deformable mirror characteristics such as actuator count and pitch affect source generation is also included.

Lung Ct Radiomics: An Overview Of Using Images As Data, Samuel Hunt Hawkins

USF Tampa Graduate Theses and Dissertations

Lung cancer is the leading cause of cancer-related death in the United States and worldwide. Early detection of lung cancer can help improve patient outcomes, and survival prediction can inform plans of treatment. By extracting quantitative features from computed tomography scans of lung cancer, predictive models can be built that can achieve both early detection and survival prediction. To build these predictive models, first a detected lung nodule is segmented, then image features are extracted, and finally a model can be built utilizing image features to make predictions. These predictions can help radiologists improve cancer care.

Building predictive models based …