Quantum Concepts Research Articles

Priority based round robin (PBRR) CPU scheduling algorithm

<p>This paper introduce a new approach for scheduling algorithms which aim to improve real time operating system CPU performance. This new approach of CPU Scheduling algorithm is based on the combination of round-robin (RR) and Priority based (PB) scheduling algorithms. This solution maintains the advantage of simple round robin scheduling algorithm, which is reducing starvation and integrates the advantage of priority scheduling. The proposed algorithm implements the concept of time quantum and assigning as well priority index to the processes. Existing round robin CPU scheduling algorithm cannot be dedicated to real time operating system due to their large waiting time, large response time, large turnaround time and less throughput. This new algorithm improves all the drawbacks of round robin CPU scheduling algorithm. In addition, this paper presents analysis comparing proposed algorithm with existing round robin scheduling algorithm focusing on average waiting time and average turnaround time.</p>

Stern-Gerlach experiment with arbitrary spin: Temporal evolution and entanglement

Because it has disclosed basic quantum properties and concepts, the Stern-Gerlach experiment (SGE) has been fundamental for the development of quantum mechanics; for example, it was particularly used to model the measurement problem on the quantum world. Despite being almost one hundred years old, the SGE is still providing new valuable insights in the development and understanding of quantum mechanics. In this paper, by using the evolution operator method, we derive the equations that provide the time evolution of the quantum state of a particle with arbitrary spin s in the Stern-Gerlach apparatus. Such temporal evolution shows quantum entanglement between the degrees of freedom of the particle. We theoretically study, through the von Neumann entropy, the entanglement that arose between the degrees of freedom of the system for the case when the particle is polarized with an arbitrary angle $ \theta$ , analyzing how the entanglement depends on this angle $ \theta$ .

Poetry and Quantum Physics: Towards the Same Realism?

This chapter focuses on the concept of reality in Adonis’ poetry and the theoretical physics developed by Basarab Nicolescu. Do they conceive reality in the same way? In this brief comparison, I seek to show that, despite different languages, poetry and quantum physics tend towards the same realism, namely the deep conviction of a veiled Real manifesting itself under numerous faces. These two activities that aim to know and reflect reality are based on how we live our relationships with all forms and at all scales of life. Consequently, they depend on both the object as an absolute entity and the subject who lives it, that is, on the subject-object connection. Beyond this famous relativism which is not the only criterion for the quantum and poetic conception of reality, the main debate, which will be mine in this article, concerns the absolute existence of the objective reality and therefore the way to access and describe it.

Quantum well photoelastic comb for ultra-high frequency cavity optomechanics

Optomechanical devices operated at their quantum limit open novel perspectives for the ultrasensitive determination of mass and displacement, and also in the broader field of quantum technologies. The access to higher frequencies implies operation at higher temperatures and stronger immunity to environmental noise. We propose and demonstrate here a new concept of quantum well photoelastic comb for the efficient electrostrictive coupling of light to optomechanical resonances at hundreds of GHz in semiconductor hybrid resonators. A purposely designed ultra-high resolution Raman spectroscopy set-up is exploited to evidence the transfer of spectral weight from the mode at 60 GHz to modes at 190–230 GHz, corresponding to the 8th and 10th overtone of the fundamental breathing mode of the light-sound cavities. The coupling to mechanical frequencies two orders of magnitude larger than alternative approaches is attained without reduction of the optomechanical constant g0. The wavelength dependence of the optomechanical coupling further proves the role of resonant photoelastic interaction, highlighting the potentiality to access strong-coupling regimes. The experimental results show that electrostrictive forces allow for the design of devices optimized to selectively couple to specific mechanical modes. Our proposal opens up exciting opportunities towards the implementation of novel approaches applicable in quantum and ultra-high frequency information technologies.

Lasers, stability, and numbers

Can insight familiar from quantum physics be used to uncover unsuspected features of classical dynamical systems? Is it possible to discover signatures of familiar quantum concepts in the realm of classical dynamics? For the wide class of systems governed by polynomial equations of motion, this paper argues that the concept of entanglement has a purely classical analogon, illustrating the analogy analytically for two paradigmatic systems, in one and in two-dimensions. The analogy emerges from properties of simple equations of motion of lasers, by demonstrating that complete sets of periodic modes may be encoded into a single orbital equation, a mode carrier, which parameterizes the entire set. The open question of mode isomorphism is also briefly addressed in the context above. Carriers provide a fresh technique for tracking and controlling classical dynamical systems, putting the emphasis on the study of orbital equations instead of orbital points.

Quantum walks for the determination of commutativity of finite dimensional algebras

Quantum walks provide a framework for the construction of quantum algorithms. Based on this approach, we consider different walks for testing the commutativity of a finite dimensional algebra. In particular, we consider Szegedy’s and Santos’ quantum walks constructed from complete and torus graphs. Results of numerical experiments are presented, showing that for some choices of the quantum walks we can obtain better detections probabilities than with previous quantum algorithms addressing this problem that were based on Grover’s quantum search. Additionally, we introduce a general notion of quantum detection system that encompasses all the methods considered in this work, among others, and develop the concept of quantum hitting time for this kind of systems as an extension of Szegedy’s seminal ideas.

USING ANDROID-BASED EQUATION PLOTTERS AS SUPPORTING TOOLS FOR TEACHING AND LEARNING ATOMIC ORBITALS

Chemistry undergraduate students are required to master the theory of quantum mechanics as the basic requirement to study the properties of the submicroscopic particle. However, many studies showed the students’ difficulties to bring the quantum mechanical concept to the macroscopic world and vise-versa. The use of computer visualization tool will very useful for teaching and learning the quantum concept, especially electron and its related atomic orbitals. This technological report paper demonstrates some of the Android-based applications i.e FuncXY, TriPlot 3D Graphing, and Graphing calculator to effectively, quickly, and accurately convert wave functions into various hydrogen atomic orbital visualizations. By selecting spherical coordinate and entering wave equation, these smartphone graphical devices visualize three-dimensional atomic orbitals. Users are also easy to rotate, zoom and manipulate the object. Finally, these user-friendly plotters are very recommended to assist chemistry educators in teaching quantum mechanics.

A Holistic Picture of Physics Student Conceptions of Energy Quantization, the Photon Concept, and Light Quanta Interference

A detailed investigation of student conceptions of quantum phenomena is needed, both to characterize student understanding of quantum concepts and to inform how we might teach quantum mechanics (QM). In this vein, in-depth semi-structured interviews were conducted with 35 students who majored in physics and received university-level QM instructions. Interview protocols were used and based on three quantum contexts: the quantization of energy in explaining the blackbody radiation, the photon concept in explaining the photoelectric effect, and light quanta in explaining the gradual formation of an interference pattern in the cases of low-intensity light beam. By applying a developmental phenomenographic analysis of the interview responses, three description categories (i.e., general patterns behind the conceptual understandings used in explaining each quantum contexts) were identified. These categories of descriptions revealed that most students’ thinking regarding foundational concepts in QM ranged from naive and deficient descriptions based on classical ontologies to simple hybrid and/or mixed models of classical and quantum conceptions. Regarding learning QM, the study found that the perspective of naive and classical ontologies in explaining quantum phenomena influenced students’ responses; they made incorrect generalizations and/or inappropriate links to the concepts learned in classical physics; and patterns of incorrect notions of QM are analogous to those that were documented. Besides, the study confirmed that students’ conceptual difficulties with QM are real, stable over time, and cross-cultural. It seems that the challenge to make QM interesting, effective, and relevant for physics students is a universal concern that knows no boundaries.

Post-Ehrenfest many-body quantum interferences in ultracold atoms far out of equilibrium

Far out-of-equilibrium many-body quantum dynamics in isolated systems necessarily generate interferences beyond an Ehrenfest time scale, where quantum and classical expectation values diverge. Of great recent interest is the role these interferences play in the spreading of quantum information across the many degrees of freedom, i.e.~scrambling. Ultracold atomic gases provide a promising setting to explore these phenomena. Theoretically speaking, the heavily-relied-upon truncated Wigner approximation leaves out these interferences. We develop a semiclassical theory which bridges classical and quantum concepts in many-body bosonic systems and properly incorporates such missing quantum effects. For mesoscopically populated Bose-Hubbard systems, it is shown that this theory captures post-Ehrenfest quantum interference phenomena very accurately, and contains relevant phase information to perform many-body spectroscopy with high precision.

Little bits of diamond: Optically detected magnetic resonance of nitrogen-vacancy centers

We give instructions for the construction and operation of a simple apparatus for performing optically detected magnetic resonance measurements on diamond samples containing high concentrations of nitrogen-vacancy (NV) centers. Each NV center has a spin degree of freedom that can be manipulated and monitored by a combination of visible and microwave radiation. We observe Zeeman shifts in the presence of small external magnetic fields and describe a simple method to optically measure magnetic field strengths with a spatial resolution of several microns. The activities described are suitable for use in an advanced undergraduate lab course, powerfully connecting core quantum concepts to cutting edge applications. An even simpler setup, appropriate for use in more introductory settings, is also presented.

A Quantum based Evolutionary Algorithm for Stock Index and Bitcoin Price Forecasting

Quantum computing has emerged as a new dimension with various applications in different fields like robotic, cryptography, uncertainty modeling etc. On the other hand, nature inspired techniques are playing vital role in solving complex problems through evolutionary approach. While evolutionary approaches are good to solve stochastic problems in unbounded search space, predicting uncertain and ambiguous problems in real life is of immense importance. With improved forecasting accuracy many unforeseen events can be managed well. In this paper a novel algorithm for Fuzzy Time Series (FTS) prediction by using Quantum concepts is proposed in this paper. Quantum Evolutionary Algorithm (QEA) is used along with fuzzy logic for prediction of time series data. QEA is applied on interval lengths for finding out optimized lengths of intervals producing best forecasting accuracy. The algorithm is applied for forecasting Taiwan Futures Exchange (TIAFEX) index as well as for Bitcoin crypto currency time series data as a new approach. Model results were compared with many preceding algorithms.

Blood Will Tell: Native Americans and Assimilation Policy by Katherine Ellinghaus

Reviewed by: Blood Will Tell: Native Americans and Assimilation Policy by Katherine Ellinghaus Ryan W. Schmidt Blood Will Tell: Native Americans and Assimilation Policy. By Katherine Ellinghaus. Lincoln: University of Nebraska Press, 2017. ix + 180 pp. Notes, bibliography, index. $40.00 cloth. Since the nineteenth century, Native Americans have been forced to self-identify through various policies imposed by the United States government. The complex question of "Who is an Indian?" has been a struggle to define. In doing so, a major thread centers on blood quantum, a metaphorical and fluid concept easily amenable to quantification. The assimilation process was fraught with the use of blood to define "Indianness." However, few have given consideration to how blood quantum came to be infused with federal policies of who was and was not an "Indian." In Blood Will Tell, Ellinghaus does not attempt to answer "who is an Indian," but rather, she asks "what kinds of Indian identities were in production during a given historical moment?" Emphasis is placed on how "mixed bloods" were treated and how their status rationalized colonialist policy of land theft and redefinition of status. Ellinghaus focuses on the Assimilation Period (1887 to 1934) using diverse case studies pulled from archival sources. Blood, in this context, can be understood as a "trope," or a metaphorical guide to racist colonialist discourse. Three major tropes are discussed: (1) a greater degree of white blood made Indians smarter and more "competent," while full-blood Indians were helpless victims; (2) blood ensured authenticity—any non-Indian blood was seen as contaminating calling into question an individual's status and membership; and (3) the treatment of those with African American ancestry differed significantly from those with European ancestry. Stages are used in the book to convey how blood went from arbitrary to official. In Stage 1 (chapters 1 and 2), the author focuses on the enrollment process among the Anishinaabeg of Minnesota and the "Five Tribes" of the American Southeast, forcibly moved to Oklahoma. In both cases, mixed bloods had difficulties convincing officials of status and tribal membership, and therefore theft of land and tribal rights were commonplace. In Stage 2 (chapter 3), the unofficial policy of "competency" takes center stage, as individuals of mixed descent were targeted in order to release them from a government trust and enable them to sell land, often under duplicitous circumstances, to white settlers. The last stage (chapter 4) came in 1934, when official legislation partly defined Indian status based on their fraction of blood and cemented this folk biology concept in the public's mind and federal Indian policy. The final chapter explores how Virginia disenfranchised Indians due to their African American ancestry. In all cases, Native groups and individuals resisted these policies or attempted to renegotiate the process based on inclusive definitions of identity or sovereignty. Overall, this book makes a significant contribution to how we interpret assumptions about ethnicity, skin color, and cultural behavior—from low-level civil servants to official ideology to indigenous notions of identity. It is a welcome addition to furthering our understanding of blood quantum and Native American policy. [End Page 439] Ryan W. Schmidt School of Archaeology University College, Dublin Copyright © 2018 The Center for Great Plains Studies and The University of Nebraska Press

Building Transdisciplinary Urban Space (Part I): Theoretical Transurbanism

This paper is the first part of  a  set  of three papers that  utilizes  the  classification of  transdisciplinarity  into  theoretical,  phenomenological and experimental transdisciplinarity (Nicolescu 2010) to suggest some fundamental perspectives and concepts that would be required in order to start  building  a  transdisciplinary  vision for urban space in research. The work is divided into three papers. In this paper we deal with Theoretical transdisciplinarity in urbanism, which needs to take into account the dialectical process of scaling and the interrelationship among various spatial scales; it also needs to come to terms with the idea of relationality of urban space, a humanistic view of space and place, the “poetics of space,” and a clear understanding of the idea of space in contemporary physics theories such as quantum gravity, together with an understanding of visual thinking. In the second paper we deal with Phenomenological transdisciplinarity as applied to urbanism, or the experience of the built space, which needs to transcend both intellectualism and empiricism via Merleau Ponty’s and Lefebvre’s triad of spatial practices, representational  space and spaces of representation, differential space, and Soja’s thirdspace; it also makes use of the architectural concepts of schemata, diagram and type; further, phenomenological transurbanism uses the concept of palimpsest in order to account for the experience of time in space. The third paper deals with Experimental transdisciplinarity, which in urbanism takes into account basic quantum concepts such as non-locality, entanglement, discontinuity, non-separability, and aims at explaining processes of planetary urbanization in the so-called “Anthro- pocene,” characterized by glocalization, hybridization, complexity, sustainability, remembrance and the reality of digital spaces.

Investigation of the role of writing-to-learn in promoting student understanding of light–matter interactions

Fundamental quantum chemistry concepts—quantization of energy, electronic structure, and light–matter interaction—are essential for understanding chemistry and spectroscopy, an important tool for studying molecules. However, very few studies have investigated how students learn and understand these concepts or how their learning can be supported. Drawing on the capacity of writing to support learning of difficult concepts, we designed an intervention that targeted quantum concepts in the context of the use of spectroscopy for identifying chemical composition of the Orion Nebula. A quasi-experimental design with a pre-post assessment on a control and treatment group was used to identify the gains associated with completing the WTL activity. Results from a three-tiered assessment show that WTL students significantly improved in their explanations of the concept of spectroscopic transitions and their overall confidence in their understanding. Analysis of their writing, follow-up interviews, and feedback served to explain the changes observed on the pre-post assessment.

Building Transdisciplinary Urban Space (Part II): Phenomenological Transurbanism

This paper is the second of a set of three papers that utilizes the classification of transdisciplinarity  into  theoretical,  phenomenological and experimental transdisciplinarity (Nicolescu 2010) to suggest some fundamental perspectives and concepts that would be required in order to start building a transdisciplinary vision for urban space in research. The work is divided into three papers. In the first paper we dealt with Theoretical Transurbanism. Theoretical transdisciplinarity in urbanism (the first paper) needs to take into account the dialectical process of scaling and the interrelationship among various spatial scales; it also needs to come to terms with the idea of relationality of urban space, a humanistic view of space and place, the “poetics of space,” and a clear understanding of the idea of space in contemporary physics theories such as quantum gravity. In this second paper we deal with Phenomenological transdisciplinarity as applied to urbanism, or the experience of the built space, which needs to transcend both intellectualism and empiricism via Merleau Ponty’s and Lefebvre’s triad of spatial practices, representational  space and spaces of representation, differential  space, and Soja’s thirdspace; it also makes use of the architectural concepts of schemata, diagram and type; further, phenomenological transurbanism uses the concept of palimpsest in order to account for the experience of time in space. The third paper deals with Experimental transdisciplinarity, which in urbanism takes into account basic quantum concepts such as non-locality, entanglement, discon- tinuity, non-separability, and aims at explaining processes of planetary urbanization in the so-called “Anthropocene,” characterized by glocalization, hy- bridization, complexity, sustainability, remembrance and the reality of digital spaces.

Building Transdisciplinary Urban Space (Part III): Experimental Transurbanism

This paper is the third part of a set of three papers that utilizes the classification of transdisciplinarity into theoretical,     phenomenological and experimental transdisciplinarity (Nicolescu 2010) to suggest some fundamental perspectives and concepts that would be required in order to start building a   transdisciplinary vision for urban space in research. In the first and second parts, we dealt with Theoretical and Phenomenological transdisciplinarity in urbanism. Theoretical  transdisciplinarity  in  urbanism (the first paper) needs to take into account the dialectical process of scaling and the interrelationship among various spatial scales; it also needs to come to  terms  with  the  idea  of  relationality  of  urban space, a humanistic view of space and place, the “poetics of space,” and a clear understanding of the idea of space in contemporary physics theories such as quantum gravity. Phenomenological transdisciplinarity as applied to urbanism, or the experience of the built space (explored in the second paper), needs to transcend both intellectualism and empiricism via Merleau Ponty’s and Lefebvre’s triad of spatial practices, representational  space and spaces of representation, differential  space, and Sojas thirdspace; it also makes use of the architectural concepts of schemata, diagram and type; further, phenomenological transurbanism uses the concept of palimpsest in order to account for the experience of time in space. This third paper deals with Experimental transdisciplinarity, which in urbanism takes into account basic quantum concepts such as non-locality, entanglement, discon- tinuity, non-separability, and aims at explaining processes of planetary urbanization in the so-called “Anthropocene,” characterized by glocalization, hy- bridization, complexity, sustainability, remembrance and the reality of digital spaces.

Quantum-inspired evolutionary approach for selection of optimal parameters of fuzzy clustering

Recently, Fuzzy c-Means (FCM) algorithm is most widely used because of its efficiency and simplicity. However, FCM is sensitive to the initialization of fuzziness factor (m) and the number of clusters (c) due to which it easily trapped in local optima. A selection of these parameters is a critical issue because an adverse selection can blur the clusters in the data. In the available fuzzy clustering literature, cluster validity index is used to determine the optimal number of clusters for the dataset, but these indexes may trap into the local optima due to the random selection of m. From the perspective of handling local optima problem, we proposed a hybrid fuzzy clustering approach referred as quantum-inspired evolutionary fuzzy c-means algorithm. In the proposed approach, we integrate the concept of quantum computing with FCM to evolve the parameter m in several generations. The evolution of fuzziness factor (m) with the quantum concept aims to provide the better characteristic of population diversity and large search space to find the global optimal value of m and its corresponding value of c. Experiments using three real-world datasets are reported and discussed. The results of the proposed approach are compared to those obtained from validity indexes like $$V_{CWB}$$ and $$V_{OS}$$ and evolutionary fuzzy based clustering algorithms. The results show that proposed method achieves the global optimal value of m, c with a minimum value of fitness function and shows significant improvement in the convergence times (the number of iterations) as compared to the state-of-the-art methods.

A Linear Approximate Model of Creativity in Quantum and Chaos Theory

The appearance of creativity is one of the most attractive issues in neuroscience and psychology. Creativity has been investigated qualitatively by using concepts of quantum and chaos theory since the end of the 20th century. Here, we show an explicit mathematical model which tries to explain the dynamics on the development of creativity. The present model is constructed by a linear approximation of chaos theory in nonlinear dynamical system. Also, it is the classical approximation of quantum mechanics, in which Newtonian mechanics is derived. Significant feature of the creativity is an existence of discontinuity which may relate to sudden appearance of idea. Such discontinuous nature relates not only to nonlinear dynamics but also to quantum theory. In this study, we first investigate the characteristics of creative attitudes by means of factor analysis and abstract two chief factors of the creative attitudes; that are “efforts and durability” and “independence and originality”. Moreover, we find a significant positive relationship between the emotional experiences and the two creative attitudes. Scholastic ability judged by paper tests, on the other hand, also has a significant positive relationship with the factor of “effort and durability” but not with that of “independence and originality”. Secondly, we build a mathematical model on the change of the two chief factors of creative attitudes using the linear approximation in nonlinear dynamical systems. We use the Dirac delta function to express the discontinuity. The calculated results are expressed in a relation between the novelty and the workload. The present linear approximation model should be the first one to build mathematically a predictive model of creativity.

Quantum sensing

"Quantum sensing" describes the use of a quantum system, quantum properties or quantum phenomena to perform a measurement of a physical quantity. Historical examples of quantum sensors include magnetometers based on superconducting quantum interference devices and atomic vapors, or atomic clocks. More recently, quantum sensing has become a distinct and rapidly growing branch of research within the area of quantum science and technology, with the most common platforms being spin qubits, trapped ions and flux qubits. The field is expected to provide new opportunities - especially with regard to high sensitivity and precision - in applied physics and other areas of science. In this review, we provide an introduction to the basic principles, methods and concepts of quantum sensing from the viewpoint of the interested experimentalist.

Concepts and Criteria for Blind Quantum Source Separation and Blind Quantum Process Tomography

Blind Source Separation (BSS) is an active domain of Classical Information Processing, with well-identified methods and applications. The development of Quantum Information Processing has made possible the appearance of Blind Quantum Source Separation (BQSS), with a recent extension towards Blind Quantum Process Tomography (BQPT). This article investigates the use of several fundamental quantum concepts in the BQSS context and establishes properties already used without justification in that context. It mainly considers a pair of electron spins initially separately prepared in a pure state and then submitted to an undesired exchange coupling between these spins. Some consequences of the existence of the entanglement phenomenon, and of the probabilistic aspect of quantum measurements, upon BQSS solutions, are discussed. An unentanglement criterion is established for the state of an arbitrary qubit pair, expressed first with probability amplitudes and secondly with probabilities. The interest of using the concept of a random quantum state in the BQSS context is presented. It is stressed that the concept of statistical independence of the sources, widely used in classical BSS, should be used with care in BQSS, and possibly replaced by some disentanglement principle. It is shown that the coefficients of the development of any qubit pair pure state over the states of an orthonormal basis can be expressed with the probabilities of results in the measurements of well-chosen spin components.