Bulletin of the American Physical Society
Spring 2015 Meeting of the APS New England Section
Volume 60, Number 5
Friday–Saturday, April 24–25, 2015; Boston, Massachusetts
Session B5: Poster Session 
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Room: Hariri Institute for Computing 

B5.00001: Observance of Negative Photocurrent in amorphous thin films of Se$_{75}$ Te$_{20}$ Ag$_{5}$ Dipti Sharma, R.K. Shukla, Ashok Kumar This study explores the effect of Ag$+$ ions on transient photoconductivity of thin films of Se$_{75}$Te$_{20}$Ag$_{5}$. The thin films of Se$_{75}$Te$_{20}$Ag$_{5}$ chalcogenide alloys were made by evaporation method using a vacuum chamber at HBTI Kanpur, India. This amorphous system showed the presence of negative photocurrent when white light was stopped showing on the sample. The rise and decay of photoconductivity was observed. The photoconductivity increased initially, reached to a maximum value and then decreased with time. The decay of photocurrent showed a negative current and indicated the presence of negative photoconductivity. The photoconductivity was studied as a function of temperature, and exposure times. The results have been explained in terms of interaction between photoexcited holes and Ag$+$ ions present in the system [1,2]. \\[4pt] [1] \textbf{D. Sharma}, R.K. Shukla and A. Kumar, Thin Solid Films 357 (1999) 214217 \\[0pt] [2] \textbf{D. Sharma}, R.K. Shukla, A. Singh, A. K. Nagpal and A. Kumar, Adv. Mater. Opt. Electron. 10 (2000) 251259 [Preview Abstract] 

B5.00002: Tunneling conductance in graphene ferromagnet/ superconductor junctions at finite temperature Xiaowei Li Using the extended BlonderTinkhamKlapwijk formalism, we investigate the conductance spectra of graphene ferromagnet /p wave superconductor junctions at finite temperature. It is found that the conductance spectra at finite temperature are affected by the p wave pairing symmetry. The ferromagnetic exchange energy in the ferromagnet can suppress Andreev retroreflection but enhance the specular Andreev reflection in graphene ferromagnet / p wave superconductor junctions at finite temperature. [Preview Abstract] 

B5.00003: Ionic transport across porous graphene membranes Lauren Cantley, Scott Bunch Graphene is an attractive material for applications in single molecule sensing and molecular sieving, in part due to its atomic thinness, strength and barrier properties. In this study, we examine ionic transport across a suspended singlelayer graphene membrane separating two reservoirs of aqueous ionic solution. Molecularly sized, subnm pore(s) are introduced by chemical etching, which allow for only proton transport across the graphene membrane. The pore is further opened and ionic conductance measurements are carried out to further investigate and characterize ionic transport across subnm and nmscale pores. [Preview Abstract] 

B5.00004: Charge Density Waves in MetalIntercalated Topological Insulator Nanoribbons Jeffrey Commons Topological insulators are an exciting new form of matter in which the interior is insulating while the surface supports symmetryprotected conductive states. We report on charge density wave transitions in the twodimensional layered topological insulator bismuth selenide (Bi2Se3) following intercalation with zerovalent metals. Using a previously reported intercalation method, Bi2Se3 nanoribbons were intercalated with either one or a combination of two metals. Disorderorder polytypic phase transitions were subsequently observed with insitu transmission electron microcopy. In particular, nanoribbons intercalated with both copper and iron demonstrate a superlattice at room temperature indicative of a charge density wave stabilized by intercalant ordering; heating of these nanoribbons to $\sim$ 375 $^{\circ}$C introduces several disorderorder phase transitions, which demonstrate varying degrees of reversibility on subsequent cooling. [Preview Abstract] 

B5.00005: Connecting electron and phonon spectroscopies to consistently determine quasiparticlephonon coupling on the surface of topological insulators Colin Howard, Michael ElBatanouny Photoemission and phonon spectroscopies have yielded widely varying estimates of the electronphonon coupling parameter $\lambda$ on the surfaces of topological insulators, even for a particular material and technique. We connect the results of these experiments by determining the Dirac fermion quasiparticle spectral function using information from measured spectra of a stronglyinteracting, lowlying optical surface phonon band. The manifest spectral features resulting from the coupling are found to vary on energy scales $< 1$ meV, and are distinct from those traditionally observed in the case of acoustic phonons in metals. We explore different means of determining $\lambda$ from the electron perspective and identify definitions that yield values consistent with phonon spectroscopy. [Preview Abstract] 

B5.00006: Symmetry Breaking and Friction in Phosphorene Jason Christopher, Steven Koenig, Angelo Ziletti, Bo Wen, Han Zheng, Cory Dean, Ozyilmaz Barbaros, Anna Swan, Bennett Goldberg Strain in 2D crystals tunes material properties, controllably breaking crystal symmetry, and inducing pseudo magnetic fields. Friction plays a central role in these applications because of its effect on the strain field's orientation and magnitude. We have developed a simple experiment for generating known strain fields in 2D crystals to explore phonon response and friction. Our technique utilizes 2D crystals suspended over holes etched in a Si substrate to create sealed microchambers. We place these chambers into a pressure vessel with an optical window for Raman measurements while simultaneously applying external pressure. The pressure deforms and slides the 2D material into the hole, and we map out the strained Raman spectra. The Raman active phonons of phosphorene in the backscattering configuration are the A$^1_g$, B$_{2g}$ and A$^2_g$ modes. Group theory predicts that these modes are nondegenerate, however as we strain the material we observe peak splitting, which is what is expected only for degenerate modes. This apparent discrepancy can be explained by considering the effect of strain on the Raman selection rules. Under strain the crystal symmetry is broken causing previously Raman inactive modes to become active creating an effect that appears like peak splitting. [Preview Abstract] 

B5.00007: Sitedirected Fabrication of Highquality Transferfree Freestanding 2D Membranes Pradeep Waduge, Joseph Larkin, Ismail Bilgin, Adam Graham, Kenneth Goodfellow, chitraleema chakraborty, Nick Vamivakas, Moneesh Upmanyu, Swastik Kar, Meni Wanunu We present an approach for direct growth of freestanding graphene and molybdenum disulfide (MoS2) membranes across prefabricated solidstate apertures. The freestanding 2D membranes are directly grown over microscale apertures in SiN membranes using chemical vapor deposition apparatus under appropriate temperatures and pressures. The 2D membranes grow preferentially over apertures, resulting in sealed membranes that are one to a few layers thick. The mechanisms by which these growths occur are investigated, which favor aperturelimited growth. The membranes are shown to be of great quality by atomicresolution transmission electron microscopy, Raman spectroscopy, and photo luminescence spectroscopy. In addition, we demonstrate lownoise ioncurrent recordings through nanopores fabricated in such membranes. Finally, we highlight the functionality of these devices by measuring DNA translocations through nanopores in such membranes. [Preview Abstract] 

B5.00008: Online Tutorial Video Experiments Norma Chase During Spring 2015, online tutorial video experiments provided students with valuable experience with the motion of charged particles in uniform electric fields. Firstly, the visual aspect of ``movies'' helped to bring the physics to life for many students, as did other simulation videos used as lecture demonstrations and homework. Further, students were required to produce lab reports clearly and completely demonstrating the reasoning behind all of their predictions. Online postings of Sample Data Sheets and Sample Predictions pages provided significant guidance to this end, and students were required to submit their video ``lab reports'' for rigorous grading. Based on preliminary data, it appears that the experience produced learning gains beyond that typically achieved by solving ``standard'' text book homework problems. [Preview Abstract] 

B5.00009: Disciplinary engagement in an online learning environment Lama Jaber, Vesal Dini, David Hammer, Ethan Danehy This poster describes middle school science teachers' progress in scientific inquiry in a Tufts University blended online course (complemented by periodic inperson meetings). Here, we focus on the shift that took place in teachers' participation, moving from following instructions to animating their own inquiry. This shift, we argue, was supported by a responsive teaching approach that put their thinking at the center, and by a flexible digital platform called InterLACE (``Interactive Learning and Collaboration Environment'') that facilitated collaborative knowledgebuilding and evolution of the online learning spaces. More specifically, InterLACE enabled us to change the online course structure from what we implemented over the first four weeks, to one coconstructed with participants thereafter. We see this as a primary catalyst for their disciplinary engagement and ownership of learning. [Preview Abstract] 

B5.00010: The Effect of Person's Height on Projected Soccer Ball Throw Alice O'Connor, Kimberly Farah, Dipti Sharma In this project, undergraduate science minors applied the concept of projectile motion to soccer.\footnote{D. Sharma and K. Farah, ``Introducing the `RPPTM' Model of Teaching Physics to Health Science Majors,'' Bulletin of the American Physical Society, s2014, 59 (4) B1.00005)} They explored the effect of person's height on a soccer ball's projectile motion. Does the height of a person change the range of the soccer ball? In soccer the term ``follow through'' is applied to situations when the ball is kicked. Follow through refers to the distance the leg travels after the ball is kicked. The idea is that the more a person follows through, the less height and greater distance the ball will cover. Inversely, the less the player follows through, the higher the ball will go but will not cover as great of a distance. Based on the assumption that taller individuals have longer legs, they will then therefore tend to cover a greater distance after striking the ball. Logger pro is used for data analysis and shows significant differences based on the player's height. [Preview Abstract] 

B5.00011: Physics of a Lacrosse Shot Jorge Salazar, Kimberly Farah, Dipti Sharma This experiment focused on the application of Newton's second law for determining the force placed on a lacrosse ball as a function of player weight. If a lacrosse player shoots a ball using a stick into a goal, the force can be calculated. For this experiment we tested a lacrosse shot. The independent variable in this experiment was the weight of a lacrosse ball and the player, and the dependent variable is the measured force. The controlled variables were the length of the stick.\footnote{D. Sharma and K. Farah, ``Introducing the `RPPTM' Model of Teaching Physics to Health Science Majors,'' Bulletin of the American Physical Society, s2014, 59 (4) B1.00005)} Kinematic data was collected using a motion detector and the graphical analysis software logger pro. Then, force was calculated following Newton's second law for each shot. Also power and work produced were calculated. [Preview Abstract] 

B5.00012: Cheerleading and Dance Jumps Jazmine Johnson, Kimberly Farah, Dipti Sharma In this project, undergraduate science minors measured the amount of force applied when doing a pike jump and a leap. The problem of study was to determine if the force applied during a pike jump differed from the force applied during a leap jump [1]. How can Newton's second law be used and what physical parameters and quantities can be studied during this jump? The independent (manipulated) variable was jump type. The dependent (to be measured) variables were height and time. Velocity and acceleration were calculated for each jump type. The controlled variables were mass and gravity. Logger pro software was used for the project and data analysis.\\[4pt] [1] D. Sharma and K. Farah, ``Introducing the ``RPPTM'' Model of Teaching Physics to Health Science Majors,'' Bulletin of the American Physical Society, s2014, 59 (4) B1.00005) [Preview Abstract] 

B5.00013: What is the Effect of an Anaerobic versus Aerobic Cardiovascular Warm up on Power Generation? Michael Miranda, Kimberly Farah, Kenneth Altshuler, Dipti Sharma When writing strength training programs for a client or team is run, it is well known that resistance training should be done prior to cardiovascular workouts. In other words, lifts like the bench press, clean, squat, lunges, dumbbell curls, etc. should be done before any type of cardiovascular workout. The question arises as to whether or not an anaerobic or aerobic cardiovascular workout will have a great effect on power generation. In this experiment, the theory is tested by comparing how the power in a bench press varies from a bench press set performed first, and then performed after a cardio session [1]. For this experiment, both aerobic and anaerobic cardiovascular workouts were performed and compared to the baseline bench press. Logger pro software was used for the project and data analysis.\\[4pt] [1] D. Sharma and K. Farah, ``Introducing the ``RPPTM'' Model of Teaching Physics to Health Science Majors,'' Bulletin of the American Physical Society, s2014, 59 (4) B1.00005) [Preview Abstract] 

B5.00014: Force Production during Pressing Barbell Nick Woodward, Ken Altshuler, Kim Farah, Dipti Sharma This is an undergraduate project, done by science minors, which applies Newton's second law and the laws of mechanics in a real world application. In this project, the applied force produced when push pressing a 60 lb. barbell was determined. The experiment was done several times to get accurate data and analyzed using logger pro. The definition of independent, dependent and control variables were applied. Video analysis was done and results supported Newton's second law. The project provided students a means to understand Newton's Law in terms of a real life activity [1].\\[4pt] [1] D. Sharma and K. Farah, ``Introducing the ``RPPTM'' Model of Teaching Physics to Health Science Majors,'' Bulletin of the American Physical Society, s2014, 59 (4) B1.00005 [Preview Abstract] 

B5.00015: How a Runner's Velocity and Acceleration Affected by Types of Shoes Tyler Davis, Michael Miranda, Kim Farah, Dipti Sharma The problem that was studied for this undergraduate project was ``Do different types of footwear have an effect on the overall velocity and acceleration generated by someone sprinting?'' [1] The independent, dependent and control variables were considered as the types of footwear, time to cover a certain distance, and the distance required to sprint and the environment. A set distance (21.3m) was used for each trial. Velocity and acceleration were calculated using logger pro. The collected data were analyzed by logger pro and found significant differences in the types of shoes. \\[4pt] [1] D. Sharma and K. Farah, ``Introducing the ``RPPTM'' Model of Teaching Physics to Health Science Majors,'' Bulletin of the American Physical Society, s2014, 59 (4) B1.00005) [Preview Abstract] 

B5.00016: PressureEnergy Relation in Canonical 2D Dipolar Bosons: A Path Integral Monte Carlo Study Joshuah Heath, Adrian Del Maestro One of the simplest conceptual models in quantum statistical physics is a gas of noninteracting particles with bosonic symmetry. In the grand canonical ensemble, particle number and temperature are in equilibrium with an external reservoir and an exact analytical expression can be derived for the partition function at any density and chemical potential. In the canonical ensemble, the total number of particles, $N$, is fixed and an expression for the partition function can only be generated via a complicated recursion relation. In this work we apply the recursion formula to obtain the partition function, and thus all thermodynamic quantities, for up to 4 noninteracting bosons in three spatial dimensions at low temperature. Analytical results for the pressure and energy are confirmed using exact path integral quantum Monte Carlo simulations. From here, we turn on weak dipolar interactions between the particles in two spatial dimensions and illustrate how quantum Monte Carlo simulations can be used to explore the relationship between pressure and energy in a system that could be experimentally realized using ultracold atomic gases. [Preview Abstract] 

B5.00017: Inelastic xray scattering measurements to study lattice dynamics of negative thermal expansion material ScF$_{3}$ Sahan Handunkanda, Jason Hancock, Ayman Said, Vladimir Voronov Thermal expansion is one of the bestknown material properties. Although the positive thermal expansion (PTE), a tendency for a solid material to grow when heated, is the most common type, there are some materials which show negative thermal expansion (NTE). NTE is one of the new and exciting fields of materials physics. Strong, thermally persistent, isotropic NTE is unusual and has been observed in only a handful of materials. Here we present inelastic xray scattering (IXS) measurement results of single crystal ScF$_{3}$ which has strong, persistent NTE down to very low temperature. We observe softening of the phonons responsible for NTE as the temperature is lowered. The low temperature results data also show the appearance of an elastic peak which is especially strong at M and R points of reciprocal space. The results of the experiment may explain an unusual mechanical behavior of the material. [Preview Abstract] 

B5.00018: Does \textit{Helicobacter pylori} exhibit corkscrew motion while swimming? Maira Constantino, Joseph Hardcastle, Rama Bansil \textit{Helicobacter pylori} is a spiral shaped bacterium associated with ulcers, gastric cancer, gastritis among other diseases. In order to colonize the harsh acidic environment of the stomach \textit{H. pylori} has to go across the gastric mucus layer. Many studies have been conducted on the swimming of \textit{H. pylori} however none have studied the trajectory path. We present a single cell experimental study of the effects of body shape in the swimming trajectory of \textit{H. pylori} in pig gastric mucin and liquid media by a quantitative analysis of the bacterium rotation and translation using phase contrast microscopy and particle tracking techniques while simultaneously measuring the bacterium body parameters. Our measurements show very well defined helical trajectories, from which we measure the body rotation. [Preview Abstract] 

B5.00019: OSCILLATIONS from ARCTIC WARMING: Record Cold {\&} Hot, RISING SEAS Paul H. Carr Both weather extremes and global sea levels have been increasing. In New England, the winter of 2015 had record snowfall and cold temperatures. The West had temperatures of 100 deg. F. Polar vortices in the jet stream explain this (1). This stream used to be confined to the Arctic by the large temperature and pressure differences between the North Pole and the rest of the earth. In recent decades, the Arctic has warmed twice as fast as the rest of the earth. This lower temperature and pressure difference results in the jet stream's sinusoidal pattern. In some locations, cold polar air oscillates as far south as New Orleans. In other places, hot tropical air comes further north. Global sea levels are presently rising up to four times faster than in 1900. These rates extrapolate to sea level rises of 2 to 6 feet by 2100. Sea level rises of 2 to 4 feet will flood the Boston's Back Bay, including Boston University. I will show that the increasing sea level rise correlates with the increasing carbon dioxide levels. Thus, sea level rise is a better measure of global warming than temperature. REFERENCE (1) Jeff Masters. ``A Wacky Jet Stream is Making Our Weather Severe.'' ``Scientific American'' November 18, 2014. [Preview Abstract] 

B5.00020: Feynman diagrams interpreted by the Theory of Elementary Waves (TEW) Jeffrey Boyd Feynman diagrams are interpreted as pictures of elementary rays. The Theory of Elementary Waves (TEW) is unknown to most physicists. It is the only local realistic picture of the quantum world that is consistent with the Bell test experiments. Like quantum mechanics, TEW violates the Bell inequalities, but unlike QM, TEW is local and realistic. It is neither the Einstein hidden variable nor the WheelerFeynman absorber theory. Apparently we live in an ocean of zero energy elementary waves, about which we know almost nothing. We seek a picture of the world of elementary rays, using quantum mathematics as our guide. Feynman diagrams provide the pictures we seek. Such diagrams are not supposed to be pictures of reality. Rather the Feynman tradition says we should integrate across all Feynman diagrams to calculate the overall probability amplitude of a superposition. However we violate the rules and take them as pictures of reality. TEW sounds preposterous to many. Thomas Kuhn reminds us that the major paradigm shifts in science sounded preposterous to scientists of previous decades. TEW involves a MAJOR paradigm shift in both quantum and classical physics. [Preview Abstract] 

B5.00021: Viscosity of Polymer Nanocomposites with Athermal Hairy Nanoparticles Fei Chen, Dan Zhao, Sanat K. Kumar, Ophelia K.C. Tsui We studied the viscosity of polymer nanocomposites (PNC) containing silica nanoparticles (core radii, $r_{\mathrm{c}} = $ 4, 12 and 25 nm) grafted with polystyrene ligands blended with polystyrene homopolymer. Viscosity reduction, contrary to Einstein's prediction, was observed in the PNCs fulfilling the following conditions: (1) The radius of gyration of the matrix polymer ($R_{\mathrm{g}}$) is bigger than the $r_{\mathrm{c}}$ and (2) the ratio of the molecular weight of the homopolymer, P, to that of the ligands, N , is bigger than 1. Importantly, the phenomenon of viscosity reduction we found is unlike those observed previously. Specifically, previous observations had found the diameters of the particle inclusions to be smaller than the matrix $R_{\mathrm{g}}$ and also the Edwards tube diameter  fulfillment of which means that the particles may act as a plasticizer and allow for constraint release of the Edwards tube, respectively. Our result suggest that either an unaccounted mechanism exists in causing the viscosity reduction we observed or the criteria for the existing mechanisms need to be revised. [Preview Abstract] 
(Author Not Attending)

B5.00022: Stigmatic Imaging of Dielectric Nanoparticles in High Refractive Index Object Space Ryan Gelly, Steven Scherr, Derin Sevenler, Selim \"Unl\"u, Bennett Goldberg Dielectric nanoparticles do not lend themselves readily to popular superresolution and highcontrast techniques due to their nonresonant behavior, so more traditional optical approaches are necessary for their imaging. We explore some methods in classical optics to boost both the measured optical signal from these particles while simultaneously pushing the resolution limit past $\lambda/2.5$, even with modest objective lenses (NA=0.45). The two principal technologies that allow for such imaging are an interferometric reflectance imaging substrate (IRIS) and a solid immersion lens (SIL) with access to its aplanatic focal point. We have parameterized contrast and resolution using two parameters: the object space immersion medium refractive index and the relative index of the particle to the medium. At this conference, we will be presenting a simple physical model to describe how contrast and resolution should scale with these parameters, and then we will share imaging data for comparison. Additionally, we will discuss the methods and challenges of working with IRIS and SIL's in a research setting. [Preview Abstract] 

B5.00023: ABSTRACT WITHDRAWN 

B5.00024: Magnetic Resonance Imaging on Cardiovascular System for Scanned Image Quality Improvement Richard Kyung, Hwankyu Song, Jeong H. (Peter) Yoon Magnetic Resonance Image is one of the most widely used technologies to detect, diagnose, and study various diseases. However, there exist some drawbacks to the technology, such as ringing artifact and long scanning time. The purpose of the present research is to develop a more efficient low pass filter or filter function, in order to increase the resolution of the scanned image, decrease the Ringing Artifact, and decrease the time required to produce the image. In this paper, a nonconventional approach and a new filter function were proposed and tested on the cardiovascular system using the MATLAB. Using the proposed filter allowed scanned images of the cardiovascular system to be constructed faster than when square function or Gaussian function was used as filters. To improve the sharpness of the MRI image of the cardiovascular system from low contrast MRI films, high pass filter and specific filter in MATLAB was used. Also, noise removal of the magnetic resonance image using Fourier transform and mathematical morphology was presented, achieving a good tradeoff between resolution of the cardiovascular system image and computer running time. [Preview Abstract] 

B5.00025: Biophysical Analysis of Tibia Using Computational Simulations Wooyoung Choi, Jinpyo Hong, Seiyoon Oh High compressive forces can cause severe stresses on the tibial bone. Repetitive loads applied to the upper surface of the tibial bone can lead to dangerous bone damage. To reduce the undesirable effect, the tibial bone and its joint need to be analyzed using biomechanical simulation before its empirical experiment. Mathematical and physical model of a twodimensional bone model of the tibia is useful to study bone stress and fracture analysis. In this paper, MRI scanning of the tibia was studied using physical and mathematical methods. Computational approach to enhance the quality of the image was carried out for the analysis of various cases. Also, removal of ringing artifact in the magnetic resonance image using Fourier transform and mathematical morphology was presented. To improve the resolution of the tibia from low contrast MRI films, high pass filter and redesigned filter were used, achieving a good tradeoff between the code running time and resolution of the MRI image of the tibia. [Preview Abstract] 

B5.00026: The Vortex Electron and the Origin of the Bohr Radius and its Fine Structure Constant, and Pilot Waves Ernst Wall We relate the first Bohr radius to the radius of a finite sized vortex electron whose charge revolves at the speed of light speed in a Compton wavelength orbit and produces the Bohr magneton, identically. The revolving charge's impulses produce a spiraling electric field, or vortex, of Compton wavelets around the electron. A train of 43 Compton wavelets, n, emitted by the electron and reflected back from the nucleus, gives the Bohr radius $=$ (f*(0.75$+$n  re)/2 $+$ rp) $=$ 21.809394 Comptons. Here re $=$ 1/2$\pi $ and is the electron radius in Comptons and rp$=$ 0.001521 Comptons is the radius of the proton. This gives us 2$\pi $*a0 $=$ 137.0325 (26 ppm err). Here, f is a correction factor of 1.00057126 from the combined potential well and reduced mass correction. We also correct the distance for the distortion caused by the finite size of the electron, and then the resulting inverse fine structure constant is then 137.0306 ( a 39 ppm error). We also claim the Compton wavelets are equivalent to the pilot waves sought after by de Broglie and Bohm.  References: www.tachyonmodel.com, Ernst Wall, The Physics of Tachyons, Hadronic Press (1995), Ernst L. Wall, Bull of APS \textbf{59}, E2.00005~ (2014). [Preview Abstract] 

B5.00027: Combining Citizen Involvement and Government Bureaucracy to Illumination the Memorial Bridge between New Hampshire and Maine with LEDs Peter Somssich The innovative design and construction of the new Memorial Bridge connecting New Hampshire and Maine has made headlines in respective professional publications. The contributions of the Public Advisory Committee, required by federal law for such projects, has not. A subgroup, the Illumination Committee, decided that this bridge needs some enhancement to make it not only functional but as pleasing to the eye as possible. They proposed an illumination design for the bridge and raised {\$}250,000 to successfully install colorchangeable LED lighting on this bridge, making it the first ever illuminated bridge in New Hampshire. Using LED technology and the design work of John Powell (Boston), the bridge illumination can now be changed in both color scheme and switched to either static or dynamic mode, but the illumination can also be triggered by sensors, e.g. day or night. Even though this group raised all of the funding without public funds, federal and state bureaucracies were not equipped to have local citizens be willing to help beautify a federal infrastructure project. With the support of the New Hampshire Department of Transportation and the City of Portsmouth, NH, this group was able to navigate the obstacles which were even more difficult than the fundraising. [Preview Abstract] 

B5.00028: Incompleteness of General Relativity, Einstein's Errors, and Related Experiments C.Y. Lo General relativity is incomplete since it does not include the gravitational radiation reaction force and the interaction of gravitation with charged particles. General relativity is confusing because Einstein's covariance principle is invalid. There is no bounded dynamic solution for the Einstein equation. Gullstrand is right and the 1993 Nobel Prize for Physics press release is incorrect. Also, awards to Christodoulou reflect the blind faith toward Einstein and accumulated errors in mathematics. The Einstein equation with an electromagnetic wave source has no valid solution unless a photonic energystress tensor with an antigravitational coupling is added. Thus, the photonic energy includes gravitational energy. The existence of antigravity coupling implies that the energy conditions in spacetime singularity theorems of Hawking and Penrose cannot be satisfied, and are irrelevant. The positive mass theorem of Yau and Schoen is misleading, though considered as an achievement by the Fields Medal. E $=$ mc$^{2}$ is invalid for the electromagnetic energy alone. The discovery of the chargemass interaction establishes the need for unification of electromagnetism and gravitation and would explain puzzles. Experimental investigations for further results are important. [Preview Abstract] 

B5.00029: Quaternion Spacetimetime Invariance as Gravity Douglas Sweetser The square of any quaternion luckily has the Lorentz invariant interval of special relativity as its first term. \[ (dt,dx_1,dx_2,dx_3)^2=(dt^2dx_1^2dx_2^2dx_3^2,2dt\,dx_1,2dt\,dx_2,2dt\,dx_3). \] The other three spacetimestime terms are commonly ignored. Ways to vary a quaternion with a continuous function by leave the interval in the square invariant will be discussed. One method uses exponentials, leading to the hyperbolic functions found useful in special relativity. Using the same approach to keep the spacetimestime invariant leads to a dynamic interval term. By preserving the spacetimestime terms using an exponential function and the geometric source mass, an interval term is found that is similar but experimentally distinct from the Schwarzschild metric applied to spacetime 4vectors: \[ (e^{z}\,dt,e^z\,dR_i/c)^2 =(e^{2z}\,dt^2e^2z\,dR_i^2/c^2,2\,dt\,dR_i/c) \] \[ =\left(e^{\frac{2GM}{c^{2}R}}dt^{2}e^{\frac{2GM}{c^{2}R}}dR_{i}^{2}/c^{2},2\,dt\,dR_{i}/c\right) \] \[ \mathrm{if} \quad z=\frac{GM}{c^{2}R},\quad i=1,2,3. \] Spacetimestime invariance is not a field theory, so gravitons are not necessary and quantization is moot. [Preview Abstract] 

B5.00030: From competitive exclusion to neutrality: A simple model of ecological dynamics exhibits rich collective behaviors Ben Dickens We study the dynamics of a simple stochastic model of interspecies competition in a small spatial patch (such as an island), surrounded by a regional pool of immigrating species. The model, introduced by Fisher and Mehta (PNAS 2014), describes when a species will be present or absent in the local community. For weak immigration rates, we vary the mean and variance of interspecies competition coefficients to uncover a rich variety of collective behaviors. If all interspecies competition coefficients are less than some critical value, then all species will achieve stable coexistence. On the other hand, if all competition coefficients are greater than this value, then the ecosystem exhibits a noisedominated regime characterized by frequent invasions and extinctions by all species. In between, only some of the coefficients exceed this critical value and several dominant species emerge. These species remain in the local patch for almost all time, competitively excluding the other species that attempt, and fail, to invade. Remarkably, as the variance in competition approaches zero, these regimes meet a point in parameter space, a ``Hubbell Point,'' characterized by neutral dynamics. All of these claims are supported by analytic calculations and numerical simulation. [Preview Abstract] 

B5.00031: 3D Fluorescent Imaging of Fluid Flow in Rock William Shain, Hari Paudel, Thomas G. Bifano, Bennett Goldberg Imaging deep inside porous media is a classical problem that manifests in enhanced oil recovery, geological CO$_2$ storage, and many other fields. However, the strong optical scattering from the pore structure limits traditional microscopy techniques to a few pore lengths from the surface. Superpenetration MultiPhoton Microscopy (SMPM) is a technique to image through strongly scattering media by using coherent optimization of the phase front of incident light to compensate for the scattering in the material. We demonstrate that we can use SMPM to create highquality images of fluorescent beads through 40$\mu$m of calcite rock samples, and we plan to use our imaging capabilities to measure the flow characteristics of water and oil through porous rock. [Preview Abstract] 
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