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Articles 1  30 of 181
FullText Articles in Physics
Peculiar Optical Properties Of Bilayer Silicene Under The Influence Of External Electric And Magnetic Fields, ThiNga Do, Godfrey Gumbs, PoHsin Shih, Danhong Huang, ChihWei Chiu, ChiaYun Chen, MingFa Lin
Peculiar Optical Properties Of Bilayer Silicene Under The Influence Of External Electric And Magnetic Fields, ThiNga Do, Godfrey Gumbs, PoHsin Shih, Danhong Huang, ChihWei Chiu, ChiaYun Chen, MingFa Lin
Publications and Research
We conduct a comprehensive investigation of the effect of an applied electric field on the optical and magnetooptical absorption spectra for ABbt (bottomtop) bilayer silicene. The generalized tightbinding model in conjunction with the Kubo formula is efficiently employed in the numerical calculations. The electronic and optical properties are greatly diversified by the buckled lattice structure, stacking configuration, intralayer and interlayer hopping interactions, spinorbital couplings, as well as the electric and magnetic fields (Ez ˆz & Bz ˆz ). An electric field induces spinsplit electronic states, a semiconductormetal phase transitions and the Dirac cone formations in different valleys, leading to the special absorption ...
New Perspectives On The SchrödingerPauli Theory Of Electrons: Part I, Viraht Sahni
New Perspectives On The SchrödingerPauli Theory Of Electrons: Part I, Viraht Sahni
Publications and Research
SchrödingerPauli (SP) theory is a description of electrons in the presence of a static electromagnetic field in which the interaction of the magnetic field with both the orbital and spin moments is explicitly considered. The theory is described from the new perspective of the individual electron via its equation of motion or ‘Quantal Newtonian’ first law. The law is in terms of ‘classical’ fields whose sources are quantum mechanical expectation values of Hermitian operators taken with respect to the system wave function. The law states that each electron experiences an external and an internal field, the sum of which vanish ...
New Perspectives On The SchrödingerPauli Theory Of Electrons: Part Ii: Application To The Triplet State Of A Quantum Dot In A Magnetic Field, Marlina Slamet, Viraht Sahni
New Perspectives On The SchrödingerPauli Theory Of Electrons: Part Ii: Application To The Triplet State Of A Quantum Dot In A Magnetic Field, Marlina Slamet, Viraht Sahni
Publications and Research
The SchrödingerPauli (SP) theory of electrons in the presence of a static electromagnetic field can be described from the perspective of the individual electron via its equation of motion or 'Quantal Newtonian' first law. The law is in terms of 'classical' fields whose sources are quantummechanical expectation values of Hermitian operators taken with respect to the wave function. The law states that the sum of the external and internal fields experienced by each electron vanishes. The external field is the sum of the binding electrostatic and Lorentz fields. The internal field is the sum of fields representative of properties of ...
Computational Techniques For Scattering Amplitudes, Juliano A. Everett
Computational Techniques For Scattering Amplitudes, Juliano A. Everett
Publications and Research
Scattering amplitudes in quantum field theory can be described as the probability of a scattering process to happen within a high energy particle interaction, as well as a bridge between experimental measurements and the prediction of the theory.
In this research project, we explore the Standard Model of Particle Theory, it’s representation in terms of Feynman diagrams and the algebraic formulas associated with each combination.
Using the FeynArts program as a tool for generating Feynman diagrams, we evaluate the expressions of a set of physical processes, and explain why these techniques become necessary to achieve this goal.
Impact Of Fiber Parameters On Edfa And/Or Raman Amplified HighSpectralEfficiency Coherent Wdm Transmissions, Lufeng Leng
Impact Of Fiber Parameters On Edfa And/Or Raman Amplified HighSpectralEfficiency Coherent Wdm Transmissions, Lufeng Leng
Publications and Research
The impact of fiber properties is investigated for coherent systems employing polarizationdivision multiplexed highlevel quadrature amplitude modulation, wavelengthdivision multiplexing, and erbiumdoped fiber amplifier and/or distributed Raman amplification. This is done by comparing the performances of fiber links of various attenuation coefficients and effective areas via experimentally verified analytical methods. Results show that the excess noise, which originates at amplifiers compensating for the losses of filters and switches located between fiber spans, can weaken or even diminish the performance enhancement brought about by lowering the fiber attenuation coefficient, especially if distributed Raman amplification is employed. This leads to the difference ...
Study Of The Kinetic Energy Densities Of Electrons As Applied To Quantum Dots In A Magnetic Field, Marlina Slamet, Viraht Sahni
Study Of The Kinetic Energy Densities Of Electrons As Applied To Quantum Dots In A Magnetic Field, Marlina Slamet, Viraht Sahni
Publications and Research
There are three expressions for the kinetic energy density t(r) expressed in terms of its quantal source, the single‐particle density matrix: t_{A}(r), the integrand of the kinetic energy expectation value; t_{B}(r), the trace of the kinetic energy tensor; t_{C}(r), a virial form in terms of the 'classical' kinetic field. These kinetic energy densities are studied by application to 'artificial atoms' or quantum dots in a magnetic field in a ground and excited singlet state. A comparison with the densities for natural atoms and molecules in their ground state is made. The near ...
The Diverse MagnetoOptical Selection Rules In Bilayer Black Phosphorus, JhaoYing Wu, SzuChao Chen, ThiNga Do, WuPei Su, Godfrey Gumbs, MingFa Lin
The Diverse MagnetoOptical Selection Rules In Bilayer Black Phosphorus, JhaoYing Wu, SzuChao Chen, ThiNga Do, WuPei Su, Godfrey Gumbs, MingFa Lin
Publications and Research
The magnetooptical properties of bilayer phosphorene is investigated by the generalized tightbinding model and the gradient approximation. The vertical interLandaulevel transitions, being sensitive to the polarization directions, are mainly determined by the spatial symmetries of subenvelope functions on the distinct sublattices. The anisotropic excitations strongly depend on the electric and magnetic fields. A uniform perpendicular electric field could greatly diversify the selection rule, frequency, intensity, number and form of symmetric absorption peaks. Specifically, the unusual magnetooptical properties appear beyond the critical field as a result of two subgroups of Landau levels with the main and side modes. The rich and ...
Multi Institutional Quantitative Phantom Study Of Yttrium90 Pet In Pet/Mri: The MrQuest Study, Nicole M. Maughan, Mootaz Eldib, David Faul, Maurizio Conti, Mattijs Elschot, Karin Knešaurek, Francesca Leek, David Townsend, Frank P. Difilippo, Kimberly Jackson, Stephan G. Nekolla, Mathias Lukas, Michael Tapner, Parag J. Parikh, Richard Laforest
Multi Institutional Quantitative Phantom Study Of Yttrium90 Pet In Pet/Mri: The MrQuest Study, Nicole M. Maughan, Mootaz Eldib, David Faul, Maurizio Conti, Mattijs Elschot, Karin Knešaurek, Francesca Leek, David Townsend, Frank P. Difilippo, Kimberly Jackson, Stephan G. Nekolla, Mathias Lukas, Michael Tapner, Parag J. Parikh, Richard Laforest
Publications and Research
Background
Yttrium90 (^{90}Y) radioembolization involves the intraarterial delivery of radioactive microspheres to treat hepatic malignancies. Though this therapy involves careful pretreatment planning and imaging, little is known about the precise location of the microspheres once they are administered. Recently, there has been growing interest postradioembolization imaging using positronemission tomography (PET) for quantitative dosimetry and identifying lesions that may benefit from additional salvage therapy. In this study, we aim to measure the intercenter variability of ^{90}Y PET measurements as measured on PET/MRI in preparation for a multiinstitutional prospective phase I/II clinical trial.
Eight institutions participated in this ...
Diy Science Sims, James Hedberg
Dissipation Effects In Schrödinger And Quantal Density Functional Theories Of Electrons In An Electromagnetic Field, XiaoYin Pan, Viraht Sahni
Dissipation Effects In Schrödinger And Quantal Density Functional Theories Of Electrons In An Electromagnetic Field, XiaoYin Pan, Viraht Sahni
Publications and Research
Dissipative effects arise in an electronic system when it interacts with a timedependent environment. Here, the Schrödinger theory of electrons in an electromagnetic field including dissipative effects is described from a new perspective. Dissipation is accounted for via the effective Hamiltonian approach in which the electron mass is timedependent. The perspective is that of the individual electron: the corresponding equation of motion for the electron or timedependent differential virial theorem—the ‘Quantal Newtonian’ second law—is derived. According to the law, each electron experiences an external field comprised of a binding electric field, the Lorentz field, and the electromagnetic field ...
Demonstration Of UltraHigh Recyclable Energy Densities In DomainEngineered Ferroelectric Films, Hongbo Cheng, Jun Ouyang, YunXiang Zhang, David J. Ascienzo, Yao Li, YuYao Zhao, Yuhang Ren
Demonstration Of UltraHigh Recyclable Energy Densities In DomainEngineered Ferroelectric Films, Hongbo Cheng, Jun Ouyang, YunXiang Zhang, David J. Ascienzo, Yao Li, YuYao Zhao, Yuhang Ren
Publications and Research
Dielectric capacitors have the highest charge/discharge speed among all electrical energy devices, but lag behind in energy density. Here we report dielectric ultracapacitors based on ferroelectric films of Ba(Zr0.2,Ti0.8)O3 which display highenergy densities (up to 166 J cm–3) and efficiencies (up to 96%). Different from a typical ferroelectric whose electric polarization is easily saturated, these Ba(Zr0.2,Ti0.8)O3 films display a much delayed saturation of the electric polarization, which increases continuously from nearly zero at remnant in a multipolar state, to a large value under the maximum electric field, leading ...
Dynamic SelfAssembly And SelfOrganized Transport Of Magnetic MicroSwimmers, Gašper Kokot, German Kolmakov V, Igor S. Aranson, Alexey Snezhko
Dynamic SelfAssembly And SelfOrganized Transport Of Magnetic MicroSwimmers, Gašper Kokot, German Kolmakov V, Igor S. Aranson, Alexey Snezhko
Publications and Research
We demonstrate experimentally and in computer simulations that magnetic microfloaters can selforganize into various functional structures while energized by an external alternating (ac) magnetic field. The structures exhibit selfpropelled motion and an ability to carry a cargo along a predefined path. The morphology of the selfassembled swimmers is controlled by the frequency and amplitude of the magnetic field.
Experiential Learning Opportunity (Elo) And Utilization Of FieldAndData Based Information Obtained Through The Infusion Of Technology: Highlights On Nasa Stem And Earth Science Curricula, Nazrul I. Khandaker, Matthew Khargie, Shuayb Siddiqu, Sol De Leon, Katina Singh, Newrence Wills, Krishna Mahibar
Experiential Learning Opportunity (Elo) And Utilization Of FieldAndData Based Information Obtained Through The Infusion Of Technology: Highlights On Nasa Stem And Earth Science Curricula, Nazrul I. Khandaker, Matthew Khargie, Shuayb Siddiqu, Sol De Leon, Katina Singh, Newrence Wills, Krishna Mahibar
Publications and Research
There is a greater emphasis on handson involvement and critical thinking skills in the geosciences and other STEM fields to inspire and engage K 16 students to value scientific content and enable them to discover the welldocumented nature of the fundamental scientific principles needed to explain various earth science and other STEMrelated core phenomena. NASA MAA curricula are ideal for engaging K116 students in this context, since gradespecific lesson plans openup a plethora of pedagogically sound and relevant earth science activities. These include earth’s materials and properties, meteorites, robotics, hot air balloon, flight simulation, star gazing, material science, crystal ...
Stochastic Resonance In A Proton Pumping Complex I Of Mitochondria Membranes, Davneet Kaur, Ilan Filonenko, Lev Mourokh, Cornelius Fendler, Robert H. Blick
Stochastic Resonance In A Proton Pumping Complex I Of Mitochondria Membranes, Davneet Kaur, Ilan Filonenko, Lev Mourokh, Cornelius Fendler, Robert H. Blick
Publications and Research
We make use of the physical mechanism of proton pumping in the socalled Complex I within mitochondria membranes. Our model is based on sequential charge transfer assisted by conformational changes which facilitate the indirect electronproton coupling. The equations of motion for the proton operators are derived and solved numerically in combination with the phenomenological Langevin equation describing the periodic conformational changes. We show that with an appropriate set of parameters, protons can be transferred against an applied voltage. In addition, we demonstrate that only the joint action of the periodic energy modulation and thermal noise leads to efficient uphill proton ...
Holography For Field Theory Solitons, Sophia K. Domokos, Andrew B. Royston
Holography For Field Theory Solitons, Sophia K. Domokos, Andrew B. Royston
Publications and Research
We extend a wellknown Dbrane construction of the AdS/dCFT correspondence to nonabelian defects. We focus on the bulk side of the correspondence and show that there exists a regime of parameters in which the lowenergy description consists of two approximately decoupled sectors. The two sectors are gravity in the ambient spacetime, and a sixdimensional supersymmetric YangMills theory. The YangMills theory is defined on a rigid AdS4 S2 background and admits sixteen supersymmetries. We also consider a oneparameter deformation that gives rise to a family of YangMills theories on asymptotically AdS4 S2 spacetimes, which are invariant under eight supersymmetries. With ...
Quadrality For Supersymmetric Matrix Models, Sebastian Franco, Sangmin Lee, RakKyeong Seong, Cumrun Vafa
Quadrality For Supersymmetric Matrix Models, Sebastian Franco, Sangmin Lee, RakKyeong Seong, Cumrun Vafa
Publications and Research
We introduce a new duality for N = 1 supersymmetric gauged matrix models. This 0d duality is an order 4 symmetry, namely an equivalence between four different theories, hence we call it Quadrality. Our proposal is motivated by mirror symmetry, but is not restricted to theories with a Dbrane realization and holds for general N = 1 matrix models. We present various checks of the proposal, including the matching of: global symmetries, anomalies, deformations and the chiral ring. We also consider quivers and the corresponding quadrality networks. Finally, we initiate the study of matrix models that arise on the worldvolume of D ...
LightInduced Electrohydrodynamic Instability In Plasmonically Absorbing Gold Nanofluids, Sujan Shrestha, Luat T. Vuong, Jorge Luis DominguezJuarez
LightInduced Electrohydrodynamic Instability In Plasmonically Absorbing Gold Nanofluids, Sujan Shrestha, Luat T. Vuong, Jorge Luis DominguezJuarez
Publications and Research
Plasmonically absorbing nanofluids exhibit lightinduced electrokinetics. We measure an electrical response to the lightinduced RayleighBénardMarangoni convective instabilities in goldpolyvinylpyrrolidone (PVP) nanoparticles (NPs) suspended in isopropanol and water. Microampere current oscillations are measured and attributed to the presence of the AuPVP NPs with negative zeta potential, in correspondence with the accompanying thermal lens oscillations and a nanofluid thermoelectric effect. The measured electrical oscillations represent an electrohydrodynamic stability driven by light, one among many that should be observed with plasmonic nanoparticles in liquids.
Tunneling Of Hybridized Pairs Of Electrons Through A OneDimensional Channel, Godfrey Gumbs, Danghong Huang, Julie Hon, M. Pepper, Sanjeev Kumar
Tunneling Of Hybridized Pairs Of Electrons Through A OneDimensional Channel, Godfrey Gumbs, Danghong Huang, Julie Hon, M. Pepper, Sanjeev Kumar
Publications and Research
Recently, the electron transport through a quasione dimensional (quasi1D) electron gas was investigated experimentally as a function of the confining potential. We present a physical model for quantum ballistic transport of electrons through a short conduction channel, and investigate the role played by the Coulomb interaction in modifying the energy levels of twoelectron states at low temperatures as the width of the channel is increased. In this regime, the effect of the Coulomb interaction on the twoelectron states has been shown to lead to four split energy levels, including two anticrossings and two crossinglevel states. Due to the interplay between ...
General Astronomy 110 Syllabus (Zero Textbook Cost), Carlos Chaparro
General Astronomy 110 Syllabus (Zero Textbook Cost), Carlos Chaparro
Open Educational Resources
The spring 2017 syllabus for the General Astronomy Course (AST 110), developed as part of the textbook free courseware initiative at Borough of Manhattan Community College.
Glass Polymorphism In Glycerol–Water Mixtures: I. A Computer Simulation Study, David A. Jahn, Jessina Wong, Johannes Bachler, Thomas Loerting, Nicolas Giovambattista
Glass Polymorphism In Glycerol–Water Mixtures: I. A Computer Simulation Study, David A. Jahn, Jessina Wong, Johannes Bachler, Thomas Loerting, Nicolas Giovambattista
Publications and Research
We perform outofequilibrium molecular dynamics (MD) simulations of water–glycerol mixtures in the glass state. Specifically, we study the transformations between lowdensity (LDA) and highdensity amorphous (HDA) forms of these mixtures induced by compression/decompression at constant temperature. Our MD simulations reproduce qualitatively the density changes observed in experiments. Specifically, the LDA–HDA transformation becomes (i) smoother and (ii) the hysteresis in a compression/ decompression cycle decreases as T and/or glycerol content increase. This is surprising given the fast compression/decompression rates (relative to experiments) accessible in MD simulations. We study mixtures with glycerol molar concentration wg = 0–13 ...
Orbifold Reduction And 2d (0,2) Gauge Theories, Sebastian Franco, Sangmin Lee, RakKyeong Seong
Orbifold Reduction And 2d (0,2) Gauge Theories, Sebastian Franco, Sangmin Lee, RakKyeong Seong
Publications and Research
We introduce Orbifold Reduction, a new method for generating 2d (0; 2) gauge theories associated to D1branes probing singular toric CalabiYau 4folds starting from 4d N = 1 gauge theories on D3branes probing toric CalabiYau 3folds. The new procedure generalizes dimensional reduction and orbifolding. In terms of Tdual configurations, it generates brane brick models starting from brane tilings. Orbifold reduction provides an agile approach for generating 2d (0; 2) theories with a brane realization. We present three practical applications of the new algorithm: the connection between 4d Seiberg duality and 2d triality, a combinatorial method for generating theories related by triality ...
Nnll Resummation For The Associated Production Of A Top Pair And A Higgs Boson At The Lhc, Alessandro Broggio, Andrea Ferroglia, Ben D. Pecjak, Li Lin Yang
Nnll Resummation For The Associated Production Of A Top Pair And A Higgs Boson At The Lhc, Alessandro Broggio, Andrea Ferroglia, Ben D. Pecjak, Li Lin Yang
Publications and Research
We study the resummation of soft gluon emission corrections to the production of a topantitop pair in association with a Higgs boson at the Large Hadron Collider. Starting from a softgluon resummation formula derived in previous work, we develop a bespoke partonlevel Monte Carlo program which can be used to calculate the total cross section along with differential distributions. We use this tool to study the phenomenological impact of the resummation to nexttonexttoleading logarithmic (NNLL) accuracy, finding that these corrections increase the total cross section and the differential distributions with respect to NLO calculations of the same observables.
Brane Brick Models In The Mirror, Sebastian Franco, Sangmin Lee, RakKyeong Seong, Cumrun Vafa
Brane Brick Models In The Mirror, Sebastian Franco, Sangmin Lee, RakKyeong Seong, Cumrun Vafa
Publications and Research
Brane brick models are Type IIA brane configurations that encode the 2d N = (0; 2) gauge theories on the worldvolume of D1branes probing toric CalabiYau 4folds. We use mirror symmetry to improve our understanding of this correspondence and to provide a systematic approach for constructing brane brick models starting from geometry. The mirror configuration consists of D5branes wrapping 4spheres and the gauge theory is determined by how they intersect. We also explain how 2d (0; 2) triality is realized in terms of geometric transitions in the mirror geometry. Mirror symmetry leads to a geometric unification of dualities in different dimensions ...
Supergroups In Critical Dimensions And Division Algebras, Čestmir Burdik, Sultan Catto, Yasemin Gürcan, Amish Khalfan, Levent Kurt, V. Kato La
Supergroups In Critical Dimensions And Division Algebras, Čestmir Burdik, Sultan Catto, Yasemin Gürcan, Amish Khalfan, Levent Kurt, V. Kato La
Publications and Research
We establish a link between classical heterotic strings and the groups of the magic square associated with Jordan algebras, allowing for a uniform treatment of the bosonic and superstring sectors of the heterotic string.
Electron Correlations In An Excited State Of A Quantum Dot In A Uniform Magnetic Field, Marlina Slamet, Viraht Sahni
Electron Correlations In An Excited State Of A Quantum Dot In A Uniform Magnetic Field, Marlina Slamet, Viraht Sahni
Publications and Research
Electron correlations in a twoelectron twodimensional ‘artificial atom’ or quantum dot (with harmonic confining potential) in the presence of a uniform magnetic field in an excited singlet state are studied via quantal density functional theory (QDFT). QDFT allows for the separation of the electron correlations due to the Pauli exclusion principle and Coulomb repulsion, as well as the determination of the contribution of these correlations to the kinetic energy. The QDFT mapping is from the excited state of the quantum dot to one of noninteracting fermions in their ground state possessing the same basic variables of the density and physical ...
Generalization Of The Schrödinger Theory Of Electrons, Viraht Sahni
Generalization Of The Schrödinger Theory Of Electrons, Viraht Sahni
Publications and Research
The Schrödinger theory for a system of electrons in the presence of both a static and timedependent electromagnetic field is generalized so as to exhibit the intrinsic selfconsistent nature of the corresponding Schrödinger equations. This is accomplished by proving that the Hamiltonian in the stationarystate and timedependent cases {\hat{H}; \hat{H}(t)} are exactly known functionals of the corresponding wave functions {\Psi; \Psi(t)}, i.e. \hat{H} = \hat{H}[\Psi] and \hat{H}(t) = \hat{H}[\Psi(t)]. Thus, the Schrödinger equations may be written as \hat{H}[\Psi]\Psi = E[\Psi]\Psi and \hat{H}[\Psi(t ...
Schrödinger Theory Of Electrons In Electromagnetic Fields: New Perspectives, Viraht Sahni, XiaoYin Pan
Schrödinger Theory Of Electrons In Electromagnetic Fields: New Perspectives, Viraht Sahni, XiaoYin Pan
Publications and Research
The Schrödinger theory of electrons in an external electromagnetic field is described from the new perspective of the individual electron. The perspective is arrived at via the timedependent "Quantal Newtonian" law (or differential virial theorem). (The timeindependent law, a special case, provides a similar description of stationarystate theory). These laws are in terms of "classical" fields whose sources are quantal expectations of Hermitian operators taken with respect to the wave function. The laws reveal the following physics: (a) in addition to the external field, each electron experiences an internal field whose components are representative of a specific property of ...
Rules And Mechanisms For Efficient TwoStage Learning In Neural Circuits, Tiberiu Teşileanu, Bence Ölveczky, Vijay Balasubramanian
Rules And Mechanisms For Efficient TwoStage Learning In Neural Circuits, Tiberiu Teşileanu, Bence Ölveczky, Vijay Balasubramanian
Publications and Research
Trialanderror learning requires evaluating variable actions and reinforcing successful variants. In songbirds, vocal exploration is induced by LMAN, the output of a basal gangliarelated circuit that also contributes a corrective bias to the vocal output. This bias is gradually consolidated in RA, a motor cortex analogue downstream of LMAN. We develop a new model of such twostage learning. Using stochastic gradient descent, we derive how the activity in ‘tutor’ circuits (e.g., LMAN) should match plasticity mechanisms in ‘student’ circuits (e.g., RA) to achieve efficient learning. We further describe a reinforcement learning framework through which the tutor can build ...
Generation Of Flower HighOrder Poincaré Sphere Laser Beams From A Spatial Light Modulator, T. H. Lu, T. D. Huang, J. G. Wang, L. W. Wang, Robert R. Alfano
Generation Of Flower HighOrder Poincaré Sphere Laser Beams From A Spatial Light Modulator, T. H. Lu, T. D. Huang, J. G. Wang, L. W. Wang, Robert R. Alfano
Publications and Research
We propose and experimentally demonstrate a new complex laser beam with inhomogeneous polarization distributions mapping onto highorder Poincaré spheres (HOPSs). The complex laser mode is achieved by superposition of LaguerreGaussian modes and manifests exotic flowerlike localization on intensity and phase profiles. A simple optical system is used to generate a polarizationvariant distribution on the complex laser mode by superposition of orthogonal circular polarizations with opposite topological charges. Numerical analyses of the polarization distribution are consistent with the experimental results. The novel flower HOPS beams can act as a new light source for photonic applications.
Properties Of The Schrödinger Theory Of Electrons In Electromagnetic Fields, Viraht Sahni, XiaoYin Pan
Properties Of The Schrödinger Theory Of Electrons In Electromagnetic Fields, Viraht Sahni, XiaoYin Pan
Publications and Research
The Schrödinger theory of electrons in an external electromagnetic field can be described from the perspective of the individual electron via the ‘Quantal Newtonian’ laws (or differential virial theorems). These laws are in terms of ‘classical’ fields whose sources are quantal expectations of Hermitian operators taken with respect to the wave function. The laws reveal the following physics: (a) In addition to the external field, each electron experiences an internal field whose components are representative of a specific property of the system such as the correlations due to the Pauli exclusion principle and Coulomb repulsion, the electron density, kinetic effects ...