MPC Seminar 2018

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Fall 2018

Seminar organizer: Mihaela Vajiac

The seminar talks are held in Keck Center for Science and Engineering, KC 171 (Center St. Orange, CA 92866, intersection of Center St. And Sycamore St.). Sometimes there will be a change of venue and the announcement will reflect this change.

See [http://www.chapman.edu/discover/maps-directions/index.aspx Maps and directions], Keck Center is Building 28 on the Campus Map [https://www.chapman.edu/about/_files/maps-and-directions/current-maps/campus-map.pdf Campus map]




Thursday, December 6th 2018 at 4:15pm, in Keck 171, tea and cookies at 3:45pm in Keck 370

Speaker: Dr. Bogdan Suceava, CSUF

Title: Strictly Convex Hypersurfaces Satisfying Weingarten-Type Inequalities

Abstract: Linear Weingarten surfaces in three-dimensional ambient space satisfy a relation between mean curvature and Gaussian curvature: aH^2+bK=c. We investigate whether for hypersurfaces invariant to inversions of dimensions 3, 4, and 5, there are curvature inequalities similar to the classical Weingarten condition. We also consider the globalization of these pointwise inequalities. This question is suggested by the investigations of Bang-Yen Chen’s fundamental inequalities, as we reflect on the geometric interpretations of these relations.Additionally, we plan to discuss other related inequalities, investigated in recent works written with Mihaela Vajiac, Nicholas Brubaker, and Leonard Giugiuc, respectively.




Friday, November 30th 2018 at 2:00pm, in Keck 171, tea and cookies at 1:30pm in Keck 370

Speaker: Dr. Apostolos Tzimoulis, Chapman University postdoc

Title: Proof theory and algebraic semantics for predicate logics

Abstract: I will start with recasting classical first-order logic in an algebraic and proof-theoretic framework based on Lawvere's theory of hyperdoctrines. Then I will discuss the problem of obtaining general semantics for predicate non-classical logics, provide some examples, and argue that algebraic and proof-theoretic insight can help us understand better and solve this problem.




Thursday, November 29th 2018 at 4:15pm, in Keck 171, tea and cookies at 3:45pm in Keck 370

Speaker: Dr. Sabine Hossenfelder (Frankfurt Institute for Advanced Studies)

Title: Do women get fewer citations than men?

Abstract: I will talk about the results of a citation analysis on publication data from the arXiv and inspire in which we explored gender differences. I will further explain how we can use bibliometric analysis to improve the efficiency of knowledge discovery.


There is also a public talk at 7pm, See Public Talk, Argyros Forum, 7pm




Conference: Monday to Friday, November 12th to November 16th in Sandhu Conference Center

Speaker: Advances in operator theory with applications to mathematical physics

CONFERENCE: Advances in operator theory with applications to mathematical physics

Abstract: For a complete schedule, and a list of abstracts, see: Conference Webpage.



Monday, November 5th 2018 at 4:15pm, in Keck 171, tea and cookies at 3:45pm in Keck 370

Speaker: Dr. Uwe Kahler, Universidade de Aveiro,

Title: Curvature detection using Taylorlets

Abstract: The problem in detection of nodules in medical images consists of two parts: the detection of edges and the detection of curvature. For the detection of edges as elements of the wavefront set of an image shearlets appeared in the last decade as the principal approach based on approximation. But elements of the wavefront set have a problem in the sense that they are singularities with prescribed direction, but not prescribed curvature. To overcome this problem higher order shearlets, so-called Taylorlets were introduced. While we will discuss them in this talk we will also point out and discuss a principal mathematical problem arising in their application: the problem of construction of a Schwartz function with infinitely many generalized vanishing moments. We will show that Meyer’s frequency-based approach does not fit this case and provide a space-based method for its generation.




Thursday, November 1st 2018 at 4:15pm, in Keck 171, tea and cookies at 3:45pm in Keck 370

Speaker: Dr. Roman Buniy, Chapman University

Title: Tripartite entanglement of qudits

Abstract: We provide an in-depth study of tripartite entanglement of qudits. We start with a short review of tripartite entanglement invariants, prove a theorem about the complete list of all allowed values of three (out of the total of four) such invariants, and give several bounds on the allowed values of the fourth invariant. After introducing several operations on entangled states (that allow us to build new states from old states) and deriving general properties pertaining to their invariants, we arrive at the decomposition theorem as one of our main results. The theorem relates the algebraic invariants of any entanglement class with the invariants of its corresponding components in each of its direct sum decompositions. This naturally leads to the definition of reducible and irreducible entanglement classes. We explicitly compute algebraic invariants for several families of irreducible classes and show how the decomposition theorem allows computations of invariants for compounded classes to be carried out efficiently. This theorem allows us to compute the invariants for the infinite number of entanglement classes constructed from irreducible components. We proceed with the complete list of the entanglement classes for three qutrits with decompositions of each class into irreducible components, and provide a visual guide to interrelations of these decompositions. We conclude with numerous examples of building classes for higher spin qudits.




Friday, October 26th at 3:00pm, in Keck 171, tea and cookies at 2:30pm in Keck 370

Speaker: Dr. Askery Canabarro, Federal University of Alagoas - BRAZIL

Title: Statistical and Machine Learning for physicists, but not just Physics (part 2)

Abstract: Machine Learning has become one of the most exciting areas of modern research and application. In these talks we provide an introduction to the core concepts and tools of machine learning in a way easily understood and intuitive to physicists. The review begins by covering fundamental concepts in ML and modern statistics such as overfitting, regularization, and generalization before moving on to more advanced topics in both supervised and unsupervised learning, for instance: ensemble deep learning, auto ML and so on. We illustrate the ideas with problems we are currently involved in.


Part 2 of a series of 2 talks.



Thursday, October 25th at 4:15pm, in Keck 171, tea and cookies at 3:45pm in Keck 370

Speaker: Dr. Askery Canabarro, Federal University of Alagoas - BRAZIL

Title: Statistical and Machine Learning for physicists (part 1)

Abstract: Machine Learning has become one of the most exciting areas of modern research and application. In these talks we provide an introduction to the core concepts and tools of machine learning in a way easily understood and intuitive to physicists. The review begins by covering fundamental concepts in ML and modern statistics such as overfitting, regularization, and generalization before moving on to more advanced topics in both supervised and unsupervised learning, for instance: ensemble deep learning, auto ML and so on. We illustrate the ideas with problems we are currently involved in.


Part 1 of a series of 2 talks.



Friday, October 19th at 1:00pm, in Keck 171, tea and cookies at 2:00pm in Keck 370

Speaker: Dr. Erik Linstead, Chapman University

Title: A Convoluted Talk

Abstract: Convolutional neural networks (CNNs) represent the current state-of-the-art in machine learning for computer vision. In this talk we will discuss some interesting applications of CNNs to non-traditional domains, as well as explore what happens to CNNs when we ignore computational efficiency to more closely align with neural physiology.




Thursday, October 18th at 4:15pm, in Keck 171, tea and cookies at 3:45pm in Keck 370

Speaker: Dr. Sandu Popescu, IQS, Chapman University

Title: Dynamical quantum non-locality

Abstract: During the 50 years since its discovery, the Aharonov–Bohm effect has had a significant impact on the development of physics. Its arguably deepest implication, however, has been virtually ignored.

Next year will be the 60th anniversary of the discovery of the Aharonov–Bohm (AB) effect, one of the most surprising and quintessential effects in quantum mechanics. Since its discovery in 1959, the AB effect has made a significant impact on the development of physics. It has been generalized in a variety of directions — from a rather straightforward dual effect such as the Aharonov–Casher effect, to the celebrated Berry phase, to non-Abelian gauge theories, to Wilson loops, to anyons. During these past 60 years the impact of the AB effect has been significant indeed.

And during all these past 60 years, what I believe to be by far the deepest implication of the AB effect (discovered by Yakir Aharonov and described in his Tel Aviv University lecture notes and elsewhere) has been virtually ignored. It is an implication that transcends the specific context from which it originates, and goes directly to the very core of quantum physics: the quantum equations of motion are non-local. Without appreciating this fact, it is safe to say that no real understanding of the nature of quantum mechanics is possible.




Thursday, October 4th at 4:15pm, in Keck 171, tea and cookies at 3:45pm in Keck 370

Speaker: Dr. Justin Dressel, Chapman University

Title: Strengthening weak measurements for qubit tomography and multitime correlators

Abstract: We re-examine the measurement strength needed to perform two recent quantum information tasks with qubits: state tomography using weak values, and determining multitime correlators. Traditionally these protocols have required weak measurements that are minimally disturbing, meaning that the coupling between an investigated quantum system and a measurement device has no appreciable influence on the evolution of the system. We show that the weakness of the interaction is not in fact necessary when measuring qubits. For the case of state tomography, we report an experiment performed with neutron matter-waves that extends the notion of generalized eigenvalues for the neutron's path system to allow the exact determination of weak values using both strong and weak interactions. Experimental evidence is given that strong interactions outperform weak ones both for precision and accuracy. For the case of obtaining multitime correlators, we show a method that uses sequential generalized measurements. Specifically, if a correlator can be expressed as an average of nested (anti)commutators of operators that square to the identity, then that correlator can be determined exactly from the average of a measurement sequence of arbitrary strength. We show that both two-point and four-point (out-of-time-ordered) correlators belong to this useful class of qubit correlators.




Thursday, September 27th at 4:15pm, in Keck 171, tea and cookies at 3:45pm in Keck 370

Speaker: Dr. Matthew Leifer, Chapman University

Title: Fine Tunings and the Nature of Quantum Reality

Abstract: Despite many years of research, there is still no universally agreed upon realist interpretation of quantum theory. In this talk, I argue that the main problem is to deal with the fine-tunings implied by no-go theorems about realist approaches to quantum theory, such as Bell’s theorem. We should seek to either eliminate these fine tunings or explain them as emergent. I will give an overview of the various fine-tunings that exist in quantum theory, due to nonlocality, contextuality, lack of time-symmetry, and results on the reality of the quantum state. I will explain how we can quantify each fine tuning, and exploit them in quantum information processing tasks. If time permits, I will outline two approaches to solve the fine-tuning problem based on block universe models with retrocausality and many-worlds.




Tuesday, September 18th at 4:15pm in Keck 171, tea and cookies at 3:45pm in Keck 370

Speaker: Professor H. Turgay Kaptanoglu, Department of Mathematics, Bilkent University, Ankara

Title: Singular Integral Operators With Bergman-Besov Kernels on the ball

Abstract: Although the boundedness of the Bergman-Besov projection operators from Lebesgue classes onto Bergman-Besov spaces has been studied for several decades, the study of the boundedness of the same operators as singular integral operators between different Lebesgue classes are rather new. Some initial work has recently been done by Cheng, Fang, Wang, Yu for the weighted Bergman operator on the unit disc and by Cheng, Hou, Liu for the Drury-Arveson operator. Also Zhao has investigated certain sub-cases of the same problem as Bergman projections. The methods they employ are sporadic and specific to the particular cases they are interested in.




The 4th SYSMICS Workshop: Friday-Monday, September 14-17, in Sandhu Conference Center D1

Speaker: The 4th SYSMICS Workshop

Title: Topic of the workshop: "Duality in Algebra and Logic”

Abstract: Workshop Webpage: http://math.chapman.edu/~jipsen/sysmics/




Friday, August 31st at 3:30pm, in Beckman 404

Speaker: Dr. Philip Mannheim, Professor of Physics, University of Connecticut

Title: The Crisis in Fundamental Physics

Abstract: Cosmology deals with the the astrophysical macroscopic universe on large scales while fundamental physics deals with the particle physics microscopic universe on small ones. Recently it has become apparent that large and small scale physics are actually intertwined leading to an astro-particle picture of the universe. At the present time this picture has achieved great success, but at the same time it has led to many open questions and challenges, challenges which threaten to potentially undermine the entire picture. These challenges include dark matter, dark energy, the cosmological constant problem, quantum gravity, the status of supersymmetry, the multiverse picture, extra space-time dimensions, and the nature of the Higgs boson. In this talk we review these issues and suggest that their resolution would require a paradigm shift in our view of the universe.




Friday, August 31st at 1:00pm, Keck 171, lunch with the speaker in the Faculty Club at noon

Speaker: Dr. Philip Mannheim, Professor of Physics, University of Connecticut

Title: Why physicists are interested in differential geometry

Abstract: Ever since Einstein's development of gravity theory, general relativity and differential geometry have been central components of physics research and of our understanding of the universe. Of special interest is how gravity can interface with the other fundamental forces, the nuclear force, the weak force, and especially the electromagnetic force. In this talk we describe some of the motivation and central achievements for general relativity, and discuss some proposed generalizations of it such as torsion and Weyl geometry that might lead to a purely geometric unification of the fundamental forces.




Thursday, August 30th at 4:00pm, Keck 171, tea and cookies at 3:30pm in Keck 370

Speaker: Dr. Philip Mannheim, Professor of Physics, University of Connecticut

Title: Quantum Conformal Gravity

Abstract: Conformal symmetry is a natural symmetry in physics since it is the full symmetry of the light cone. If all particles are to get their masses by symmetry breaking then conformal symmetry is the symmetry of the unbroken Lagrangian. Like Yang-Mills theories conformal symmetry has a local extension, namely conformal gravity, a pure metric-based candidate alternative to the non-conformal invariant standard Newton-Einstein theory of gravity. With its dimensionless coupling constant quantum conformal gravity is power counting renormalizable. Since its equations of motion are fourth-order derivative equations conformal gravity has long been thought to possess unacceptable ghost states of negative norm that would violate unitarity. However on constructing the quantum Hilbert space Bender and Mannheim found that this not to be the case. Conformal gravity is thus offered as a completely consistent and unitary quantum theory of gravity, one that requires neither the extra dimensions nor the supersymmetry of string theory. As formulated via local conformal invariance there is no intrinsic classical gravity, with gravity instead being intrinsically quantum-mechanical, with the observed classical gravity being output rather than input. The contribution of the graviton loops of conformal gravity enables conformal gravity to solve the cosmological constant problem. Like Yang-Mills the potential of conformal gravity contains both a Newtonian term and a linear potential. Together with a quadratic potential that the theory also contains conformal gravity is able to explain the systematics of galactic rotation curves without any need for galactic dark matter. Since all mass is to be dynamical there cannot be a fundamental double-well Higgs potential in the theory. Instead, the Higgs boson is generated dynamically, with the hierarchy problem then being solved.




Thursday, August 23rd at 4:00pm, Keck 171, tea and cookies at 3:30pm in Keck 370

Speaker: Dr. Gunduz Caginalp, Professor of Mathematics, University of Pittsburgh

Title: Volatility Maxima as a Forecaster of Trading Price Extrema

Abstract: This is joint work with Carey Caginalp. The relationship between price volatility and a market extremum is examined using a fundamental economics model of supply and demand. By examining randomness through a microeconomic setting, we obtain the implications of randomness in the supply and demand, rather than assuming that price has randomness on an empirical basis. Within a very general setting the volatility has a maximum that precedes the extremum of the price. A key issue is that randomness arises from the supply and demand, and the variance in the stochastic differential equation governing the logarithm of price must reflect this. Analogous results are obtained by further assuming that the supply and demand are dependent on the deviation from fundamental value of the asset.




Spring 2018


The seminar talks are in Von Neumann Hall VN 116 (545 W Palm Ave corner of W Palm Ave and railroad, Orange, CA 92866). Sometimes there will be a change of venue and the announcement will reflect this change.

See [http://www.chapman.edu/discover/maps-directions/index.aspx Maps and directions], Von Neumann Hall is Building 48 on the Campus Map [https://www.chapman.edu/about/_files/maps-and-directions/current-maps/campus-map.pdf Campus map]



Friday, May 11th at 3:00pm, Von Neumann Hall, tea and cookies at 2:30pm

Speaker: Dr. Nadia Ahmed, Saddleback

Title: Consumer-centric Residential Demand Side Management

Abstract: Energy Management Systems (EMS) are mainly price driven with minimal consumer interaction. To improve the effectiveness of EMS in the context of demand response, an alternative EMS control framework driven by resident behavior patterns is developed. Using hidden Markov modeling techniques, the EMS detects consumer behavior from real-time aggregate consumption and a pre-built dictionary of reference models. These models capture variations in consumer habits as a function of daily living activity sequence. Following a training period, the system identifies the best fit model which is used to estimate the current state of the resident. When a request to activate a time-shiftable appliance is made, the control agent compares grid signals, user convenience constraints, and the current consumer state estimate to predict the likelihood that the future aggregate load exceeds a consumption threshold during the operating cycle of the requested device. Based on the outcome, the control agent initiates or defers the activation request. In an extension of this work, a battery health conscious stochastic dynamic programming control framework is introduced as part of a greater cyber physical system which incorporates the harvesting unit, the storage unit, the residential load profile, the weather, the weather forecast, the utility, and consumer preferences into a unified Markov decision process.





IQS Live Podcast, Monday, April 16th at 6:00pm, 1888 Center, 115 North Orange Street

Speaker: Adam Becker

Title: What Is Real? The Unfinished Quest for the Meaning of Quantum Physics

Abstract: IQS Live podcast recording and book signing with Adam Becker, author of:

"What Is Real? The Unfinished Quest for the Meaning of Quantum Physics”

Monday April 16 6pm-8pm 1888 Center, 115 North Orange Street, Orange, CA 92866

Produced in partnership with the Institute for Quantum Studies, Chapman University


Organized by IQS. Free admission, but seating is limited so you have to RSVP at the following link: Event Registration




Friday, April 13th at 3:30pm, Von Neumann Hall, tea and cookies at 3:00pm

Speaker: Dr. Jose Raul Gonzalez Alonso, Chapman University

Title: Quantum Chaos, Information Scrambling, and Out-of-time-ordered Correlators

Abstract: Out-of-time-ordered-correlators (OTOCs) have emerged as a useful tool to study quantum chaos and the scrambling and delocalization of information in many-body systems. While challenging, their experimental measurement has been achieved in NMR, trapped ion, and superconducting systems. In this talk, I will review the different open problems at the intersection of quantum chaos, information scrambling, and OTOCs and the recent progress in solving them.




Friday, April 6th Sixth annual Computational and Data Sciences Graduate Conference

Speaker: Chapman University Graduate Students, 9:15am - 4:30pm, Argyros Forum 209ABC

Title: Sixth annual Computational and Data Sciences Graduate Conference

Abstract: Various




Friday, March 30th at 3:00pm, Von Neumann Hall

Speaker: Kai-Wen Tu, Chapman University

Title: Fourier Transform and Signal Processing Application with a SAR Imaging Example

Abstract: In solving heat-flow problems Fourier found that a periodic function can be represented by an infinite series of sinusoidal functions. Generalization from Fourier Series to Fourier Transform and its discrete form, the Discrete Fourier Transform (DFT) will be discussed briefly. Development of a computationally efficient algorithm FFT (Fast Fourier Transform) for computing DFT will be described with MATLAB illustration. The second part of the talk will focus on a specific signal processing application using FFT. An overview of imaging radar systems with conventional aperture as well as with synthetic aperture (SAR) will be given. Image resolution will be shown to be related to pulse compression and synthetic array processing as the antenna beam creates a footprint with the continuing illumination of a designated spot. Image formation of the Spotlight imaging mode encompassing signal data collection, motion compensation, data sampling, range dechirp, azimuth compression, polar interpolation, 2-D FFT, phase correction, and pixel magnitude encoding will be presented.




Tuesday, March 20th at 3:00pm, Von Neumann Hall

Speaker: Mic Detlefsen, University of Notre Dame

Title: Some Elements of Hilbert’s Formalism

Abstract: The aim of this talk is to describe and consider the significance of a certain element of Hilbert¹s formalist viewpoint that I call its descriptive or observational element. This element played an important role in shaping Hilbert¹s distinctive approach to the consistency problem for arithmetic (and to other consistency problems). It seems not to have been generally well recognized and appreciated.



Friday, March 16th at 3:00pm, Von Neumann Hall

Speaker: Lorenzo Catani, UCL

Title: Csirelson’s bounds as a refinement of Landauer’s principle

Abstract: I will present a simple single qudit protocol that computes a non-linear function. It consists of a system in a fixed state, two gates controlled by classical dits (d-level systems) and a fixed measurement. The goal is to choose gates to optimise the average probability over all input combinations of dits to obtain the target non-linear function as output.

I will show that any strategy in the single-qudit protocol can be mapped to a strategy in a two qudits CHSH game, thus obtaining the known classical Bell bounds for the strategies that only involve classical reversible computation or quantum stabiliser computation, and Csirelson’s bounds for general quantum strategies. Since the single qudit protocol restricts the degrees of freedom to gates only, we analyse the bounds obtained in light of Landauer’s principle, showing that there is a trade-off in entropic cost versus increased success probability. The single qubit computation can perform better than the reversible bit computation, but it cannot achieve the performance of the irreversible computation. In this sense the protocol acts as an irreversibility witness. In the case of systems of dimension two (bits and qubits) these results have a clear geometric interpretation in the corresponding state spaces.

I will briefly discuss how our scheme also acts as a dimensional witness and I will conclude with some comments on the sources of non-classicality present in the current protocol since non-locality and contextuality (in its standard notions) are not present.




Friday, March 9th at 3:00pm, Von Neumann Hall

Speaker: Dr. Carey Caginalp, University of Pittsburgh

Title: Supply, Demand, Volatility and Fat Tails

Abstract: The classical equations of mathematical finance involve basic assumptions that are convenient mathematically and are essentially a particular limit of the underlying market phenomena. The assumptions involve infinite capital for arbitrage and independent Gaussian increments in relative price change. Among the consequences are an exponential decay in large deviations of relative price and volatility that is essentially constant in time. We use a basic supply/demand model to explain the fat tails phenomena based on endogenous reasons. The bubble in cryptocurrencies can also be explained in terms of this approach in which the liquidity price, namely, cash available for investing in a particular asset divided by the number of units available. Current work is focused on demonstrating that the extrema in price are accompanied by extrema in volatility. (Research in collaboration with Dr. Carey Caginalp)



IQS Workshop: Saturday, March 3rd, Argyros Forum 212

Speaker: Quantum Simulation and Quantum Walks Workshop

Title: Quantum Simulation and Quantum Walks Workshop

Abstract: Organized by IQS. For registration to this event please follow the link: Event Registration.




IQS Workshop: Thursday-Friday, March 1st and 2nd, Beckman Hall 404

Speaker: AAV Anniversary Conference - Celebrating 30 Years of Weak Values

Title: AAV Anniversary Conference - Celebrating 30 Years of Weak Values

Abstract: Organized by IQS. For registration to this event please follow the link: Event Registration.




Friday, February 23rd at 3:00pm, Von Neumann Hall

Speaker: Dr. Ken Wharton, San Jose State

Title: Spacetime-Based Retrocausal Models

Abstract: Ordinary quantum states grow exponentially with particle number, and cannot exist as a function on ordinary spacetime. But when retrocausal models are considered, the reason for this exponential growth disappears, raising the exciting prospect of some ontic description of quantum phenomena that does exist in spacetime. (In such models the spacetime-based ontic parameters need only work for the actual future measurement setting, not all possible counterfactual settings.) I will give a detailed example of such a model, which can properly account for all maximally-entangled two-qubit states. The key is an "all at once" analysis of the histories, rather than a dynamical evolution of instantaneous states. Intriguingly, the model naturally supplies a novel alternate interpretation of Weak Values.




Thursday, February 22nd at 4:00pm, Von Neumann Hall

Speaker: Adam Becker, Science Writer

Title: Myths about the history of the de Broglie-Bohm interpretation: setting the record straight

Abstract: Misconceptions about the de Broglie-Bohm interpretation of quantum mechanics appeared immediately at its first public presentation by de Broglie at Solvay in 1927. It took many years for those misconceptions to fall away. Today, we finally have a good understanding of the theory (or at least a better understanding), but there are still many common misconceptions about its history. What were the nature of the objections to de Broglie's version of the interpretation at Solvay? Why did de Broglie abandon it? What prompted Bohm to look for a new interpretation 25 years later? How were Bohm's ideas received by his contemporaries? And why did Bohm himself ultimately abandon his own ideas for another quarter of a century? There are "standard" answers to these questions, most of which are simply myths. For example, Pauli did not stump de Broglie at Solvay, Oppenheimer was generally kind to Bohm during his time on the blacklist, and Bohm's ideas were not simply ignored or dismissed out of hand by his contemporaries. In my talk, I will discuss the origins of these myths, and the far more complicated and surprising historical truths that they obscure.




Friday, February 16th at 3:00pm, Von Neumann Hall

Speaker: Eli Levenson-Falk, USC

Title: Fleas on Schrödinger's Cat: Quasiparticles in Superconducting Quantum Circuits

Abstract: Superconducting electrical circuits can be used for quantum computing, quantum simulation, ultra-low-noise amplification, and precision sensing. However, quasiparticles--electron-like single-particle excitations of the superconducting condensate--can cause loss and noise, limiting the performance of these devices. The generation mechanisms, behavior, and annihilation channels of these quasiparticles are still poorly understood, hindering efforts to eliminate them from circuits. I will review the evidence for different quasiparticle models, show measurements using Andreev bound states as quasiparticle traps, and discuss future experiments that will determine the best ways to mitigate the harmful effects of quasiparticles.




Friday, February 9th at 4:00pm, Beckman Hall 105

Speaker: Dr. J.H. Eberly, Department of Physics and Astronomy, Center for Coherence and Quantum Optics, University of Rochester

Title: Hidden Coherences and Complementarity

Abstract: Interference, duality, polarization, coherence and entanglement are a partial list of notions that belong to both quantum physics and classical optics. It has been our recent goal to bring quantum-classical links into wider view and to indicate directions in which forthcoming and future work may be able to promote discussion and lead to a more unified understanding. A starting point has often been Niels Bohr's pronouncements and explanations of complementarity, as a way to come to grips with de Broglie's duality. Related debates have engaged and challenged philosophers as well as physicists for almost a century. Complemenn-classical world's mysterious quantum features. Disputed analyses and unresolved conflicts are still debated. It seems to have escaped notice that a key element in Bohr's own defining summary has never been captured in assessments to date. We will report what we believe to be the first description of complementarity that is quantitatively complete, along with experimental evidence of completeness.



Friday, February 9th, at 2:00pm in Hashinger 150 (Irvine Lecture Hall)

Speaker: Dr. Cumrun Vafa, Harvard University

Title: Fundamental Lessons From String Theory

Abstract: String theory has been developed for more than 40 years now but it seems that we are still far from its final formulation. Nevertheless, I explain some of the highlights of what we have learned from string theory and how it revolutionizes many of the fundamental principles of physics.



Thursday, February 8th, at 7:00pm in Beckman Hall 404

Speaker: Dr. Cumrun Vafa, Harvard University

Title: Physics and Geometry

Abstract: This talk reviews the deep historical connections between geometry and physics. In modern times, the extra dimensions of string theory has provided a new opportunity for enhancing this interplay which will be illustrated by concrete examples.



Monday, February 5th at 4:00pm, Von Neumann Hall

Speaker: Dr. Ales Pultr, Charles University, Prague

Title: Point-free topology and some of its merits

Abstract: Point-free thinking, example. Points vs. (realistic) places. A glimpse of history: Synthetic and analytic geometry; classical topology as a generalized geometry is the analytic version of such a generalization. De- velopment starting in late 30ties and 40ties, how the point-free ideas connect with the classical ones (Hausdorff, Kuratowski, Caratheodory, Freudenthal). The break in the late fifties. Definition of a locale (frame). Basic concepts and how one works with them. One obtains a broader range of spaces and every generalization calls for justification. This will be done by discussing the following legitimate ques- tions. (1) Is the broader range of spaces desirable? Do we get in some sense a better theory and when? (2) Is the algebraic technique appropriate, does it not obscure the geomet- ric content? (3) Do we not lose to much information when abolishing points? We will start by briefly answering question (3) and then go to (1) and (2) presenting examples of results that are nicer, or cannot hold in the classical context at all. In particular we will emphasize the constructive aspects (facts working without choice principles, such as compactification, completion, or Stone duality - the last is so simple that it can serve also as an example of the advantage of the algebraic techniques). Note of the role of point-free topology in logic and theoretical computer science.




Monday, January 29th at 3:00pm, Von Neumann Hall, third session of the OCIE-HPML seminar

Speaker: Dr. Jamie Tappenden (USC)

Title: Frege, Carl Snell and Romanticism; Fruitful Concepts and the 'Organic/Mechanical' Distinction

Abstract: A surprisingly neglected figure in Frege scholarship is the man Frege describes (with praise that is very rare for Frege) as his "revered teacher", the Jena physics and mathematics professor Carl Snell. It turns out that there is more of interest to say about Snell than can fit into one talk, so I'll restrict attention here to just this aspect of his thought: the role of the concept of "organic", and a contrast with "mechanical". Snell turns out to have been a philosophical Romantic, influenced by Schelling and Goethe, and Kant's Critique of Judgement. In Frege's environment, the "organic/mechanical" contrast, understood in a distinctively Romantic fashion, had reached the status of "accepted, recognized cliché". More generally, Frege's environment was more saturated with what we now call ``Continental philosophy" than we might expect. This context-setting has a payoff for our reading of Frege's texts: many expressions and turns of phrase in Frege that have been regarded as vague, throwaway metaphors turn out to be literal references to ideas that would have been salient among the people in Frege spent time with day-to-day. In particular, this is true of Frege's account of "extending knowledge" via "fruitful concepts" and his rejection of the idea that logic and mathematics can be done "mechanically" (as with Jevons' logic machines, or Fischer's "aggregative mechanical thought"). When Frege appealed to "organic connection" and speaks of fruitful concepts as containing conclusions "like a plant in its seeds", he would have expected his apparent metaphors to have been understood in a very specific way, as alluding to a recognized contrast between "organic" and "mechanical" connection that was applied by Snell and those close to him not only to distinctions between biological and physical reasoning but also to distinctions of types of reasoning in arithmetic and geometry.




Monday, January 29th at 4:00pm (Beckman Hall 404)

Speaker: Peter Coffee, Vice President for Strategic Research at salesforce.com

Title: The Future That's Already Happened: Fundamental Forces of Change

Abstract: There are two ways to talk about "the future." One involves making predictions of what might happen. The other, much less speculative, solves present-day equations for a future value of time. Today, the second approach can make use of observable facts about connection, collaboration, acceleration, and introduction of machine intelligence ("Ex Machination") into devices and processes -- to give us a crisp and compelling picture of what otherwise might seem wild-eyed visions.

For registration to this event please follow the link: Event Registration.



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