Physical Sciences and Mathematics Commons^™

Urban Foraging: A Ubiquitous Human Practice Overlooked By Urban Planners, Policy, And Research, Charlie M. Shackleton, Patrick T. Hurley, Annika C. Dahlberg, Marla R. Emery, Harini Nagendra

Environment and Sustainability Faculty Publications

Although hardly noticed or formally recognized, urban foraging by humans probably occurs in all urban settings around the world. We draw from research in India, South Africa, Sweden, and the United States to demonstrate the ubiquity and varied nature of urban foraging in different contexts. Across these different contexts, we distill seven themes that characterize and thereby advance thinking about research and the understanding of urban foraging. We show that it is widespread and occurs across a variety of urban spaces and places. The species used and the local practices vary between contexts, and are in constant flux as urban …

Gaussian Guesswork: Infinite Sequences And The Arithmetic-Geometric Mean, Janet Heine Barnett

Calculus

No abstract provided.

The Roots Of Early Group Theory In The Works Of Lagrange, Janet Heine Barnett

Abstract Algebra

No abstract provided.

The Pell Equation In India, Toke Knudsen, Keith Jones

Number Theory

No abstract provided.

Generating Pythagorean Triples: A Gnomonic Exploration, Janet Heine Barnett

Number Theory

No abstract provided.

Quantifying Certainty: The P-Value, Dominic Klyve

Statistics and Probability

No abstract provided.

Quantum Control Via A Genetic Algorithm Of The Field Ionization Pathway Of A Rydberg Electron, Vincent C. Gregoric, Xinyue Kang, Zhimin Cheryl Liu, Zoe A. Rowley, Thomas J. Carroll, Michael W. Noel

Physics and Astronomy Faculty Publications

Quantum control of the pathway along which a Rydberg electron field ionizes is experimentally and computationally demonstrated. Selective field ionization is typically done with a slowly rising electric field pulse. The (1/n^*)⁴ scaling of the classical ionization threshold leads to a rough mapping between arrival time of the electron signal and principal quantum number of the Rydberg electron. This is complicated by the many avoided level crossings that the electron must traverse on the way to ionization, which in general leads to broadening of the time-resolved field ionization signal. In order to control the ionization pathway, thus …

Assessing The Supply Of Provisioning And Cultural Ecosystem Services From Urban Forests: A Philadelphia Pilot Study, Jenna Q. Detweiler

Environment and Sustainability Summer Fellows

This study develops a methodology for assessing the urban provisioning and cultural ecosystem services created by woody species in urban forests. Drawing on this methodology, the research examines these dynamics through use of an urban forest inventory and survey data for the city of Philadelphia. Findings quantify the percentage of species and corresponding percent of the tree population that are likely to be harvested by urban foragers in the city.

Inverse-Kinematics Proton Scattering On 43p, Lisa M. Skiles

Physics and Astronomy Summer Fellows

Following an experiment at the National Superconducting Cyclotron Laboratory at Michigan State University in October 2016, we study the excited states of the neutron-rich isotope 43P via inverse-kinematic proton scattering with the GRETINA y-ray tracking array. We will discuss preliminary analysis and results, including measured cross sections for populating excited states of 43P.

Engineering Electron Superpositions Using A Magnetic Field, Zoe A. Rowley, Bianca R. Gualtieri

Physics and Astronomy Summer Fellows

A Rydberg atom has a highly excited valence electron which is weakly bound and far from the nucleus. These atoms have exaggerated properties that make them attractive candidates for quantum computation and studies of fundamental quantum mechanics. The discrete energy levels of Rydberg atoms are shifted in the presence of an electric field by the Stark effect and are similarly shifted due to a magnetic field by the Zeeman effect. These effects couple the energy levels together, creating avoiding crossings. At these avoided crossings, an electron in one energy level can jump to the other.

Our goal is to be …

Quantum Physics And Relativity In Lovecraft's Fiction, Garrison Mccammon

English Summer Fellows

The early twentieth century brought about some of the best and most influential horror or weird tales ever written in the English speaking world. The most impressive and most lauded author of the group composed of such figures as Algernon Blackwood, M. R. James, Arthur Machen, Clark A. Smith, and Robert E. Howard was H. P. Lovecraft. Posthumously declared the literary successor to Edgar Allan Poe, Lovecraft’s fiction and tales of terror have cast such a huge shadow that every significant author in weird writing since his passing has claimed him as a literary heir. Lovecraft’s works were a landmark …

Optimizing An Electron's Path To Ionization Using A Genetic Algorithm, Jason Bennett, Kevin Choice

Physics and Astronomy Summer Fellows

A Rydberg atom is an atom with a highly excited and weakly bound valence electron. A widespread method of studying quantum mechanics with Rydberg atoms is to ionize the electron and measure its arrival time. We use a Genetic Algorithm (GA) to control the electron's path to ionization. The Rydberg electron's energy levels are strongly shifted by the presence of an electric field. The energy levels shift and curve, but never cross. At an avoided crossing the electron can jump from one level to the next. By engineering the electric field's time dependence, we thereby control the path to ionization. …

Inverse Kinematics Proton Scattering Of P41, Benjamin R. Klybor

Physics and Astronomy Summer Fellows

We have measured the gamma-ray spectrum of P41 using proton scattering in inverse kinematics with the NSCL/Ursinus College liquid hydrogen target and the GRETINA gamma-ray tracking array. We present preliminary results, including gamma-ray intensities and branching ratios.

Returning Thermal Advantage Instrument’S Dsc 2920 And Sdt 2960 To Functioning Order, Ethan B. Haldeman

Physics and Astronomy Summer Fellows

Thermal Advantage (TA) Instruments DSC 2920 and SDT 2960 require a computer running Windows NT 2000 and an Industry Standard Architecture (ISA) expansion card to output and record data. Due to the lack of availability for this older software and hardware, a virtual machine running Windows NT 2000, using Oracle VM VirtualBox as the virtualization software, and a GPIB-USB-SH converter were used to allow a modern computer to interface with the DSC an SDT. The Windows NT virtual machine ran the necessary TA software to communicate with the DSC and SDT and USB pass-through was used to allow the virtual …

The Definite Integrals Of Cauchy And Riemann, Dave Ruch

Analysis

Rigorous attempts to define the definite integral began in earnest in the early 1800's. One of the pioneers in this development was A. L. Cauchy (1789-1857). In this project, students will read from his 1823 study of the definite integral for continuous functions . Then students will read from Bernard Riemann's 1854 paper, in which he developed a more general concept of the definite integral that could be applied to functions with infinite discontinuities.

Rigorous Debates Over Debatable Rigor: Monster Functions In Introductory Analysis, Janet Heine Barnett

Analysis

No abstract provided.

A Compact Introduction To A Generalized Extreme Value Theorem, Nicholas A. Scoville

Topology

In a short paper published just one year prior to his thesis, Maurice Frechet gives a simple generalization one what we might today call the Extreme value theorem. This generalization is a simple matter of coming up with ``the right" definitions in order to make this work. In this mini PSP, we work through Frechet's entire 1.5 page paper to give an extreme value theorem in more general topological spaces, ones which, to use Frechet's newly coined term, are compact.

The Closure Operation As The Foundation Of Topology, Nicholas A. Scoville

Topology

No abstract provided.

Construction Of The Figurate Numbers, Jerry Lodder

Number Theory

No abstract provided.

Generating Pythagorean Triples: The Methods Of Pythagoras And Of Plato Via Gnomons, Janet Heine Barnett

Number Theory

No abstract provided.

Pascal's Triangle And Mathematical Induction, Jerry Lodder

Number Theory

No abstract provided.

Babylonian Numeration, Dominic Klyve

Number Theory

No abstract provided.

Primes, Divisibility, And Factoring, Dominic Klyve

Number Theory

No abstract provided.

Gaussian Integers And Dedekind's Creation Of An Ideal: A Number Theory Project, Janet Heine Barnett

Number Theory

No abstract provided.

Solving A System Of Linear Equations Using Ancient Chinese Methods, Mary Flagg

Linear Algebra

No abstract provided.

Microwave Assisted Dipole-Dipole Transitions, Jacob T. Paul

Physics and Astronomy Honors Papers

We explore this two photon assisted transition through computational and numerical analysis of possible energy levels. We calculate the matrix elements of the energy transition in detail discussing constants and the quantum mechanical possibilities of energy exchanges in these systems.

The goal is to better understand the energy exchange, so that moving forward we can control it. This paper covers the theoretical ends to controlling the energy transition by the way of two photon assisted transitions. The energy transitions take place between a dipole-dipole interaction, and a microwave photon.

An Introduction To A Rigorous Definition Of Derivative, Dave Ruch

Analysis

No abstract provided.

Euler's Rediscovery Of E With Instructor Notes, Dave Ruch

Analysis

No abstract provided.

Bolzano On Continuity And The Intermediate Value Theorem, Dave Ruch

Analysis

No abstract provided.

The Mean Value Theorem, Dave Ruch

Analysis

No abstract provided.