Wigner 111 - Colourful and Deep

11 Nov 2013, 06:00 → 14 Nov 2013, 22:00 Europe/Budapest

Ceremonial Hall (Díszterem) (Hungarian Academy of Sciences)

József Pálinkás (Hungarian Academy of Sciences), Peter Levai (MTA KFKI RMKI), Sándor Varró (Wigner RCP of the HAS)

Wigner 111 Scientific Symposium, Wigner 111 - Colourful & Deep

Monday, 11 November

08:00 → 09:00 Registration

09:00 → 09:20 Opening

Conveners: Prof. József Pálinkás, Dr Peter Levai (MTA KFKI RMKI)

slides Wigner_Pictures.pdf

09:20 → 10:00 Quantum Theory viewed from Wigner Phase Space

Eugene Paul Wigner’s formulation [1, 2] of quantum mechanics in phase space is completely equivalent to the ones by Werner Heisenberg, Erwin Schrödinger or Richard Feynman but offers many insights into the inner workings of quantum theory usually hidden behind the opaque curtain of the respective formalism. In the present talk we review some of them having led to the construction of focusing wave packets in free space [3], or the astonishing properties [4] of s-waves giving rise to measures of entanglement [5] based on the negative parts of the Wigner function, and tunneling [6] analyzed from phase space making contact with Unruh radiation. References [1] E.P. Wigner, On the quantum correction for thermodynamic equilibrium, Phys. Rev. 40, 749-759 (1932) [2] W.P. Schleich, Quantum Optics in Phase Space, (VCH-Wiley, Weinheim, 2001) [3] I. Bialynicki-Birula, M.A. Cirone, J.P. Dahl, M. Fedorov, and W.P. Schleich, In- and outbound spreading of a free-particle s-wave, Phys. Rev. Lett. 89, 060404 (2002) [4] J.P. Dahl, S. Varro, A. Wolf, and W.P. Schleich, Wigner functions of s waves, Phys. Rev. A 75, 052107 (2007) [5] J.P. Dahl, H. Mack, A. Wolf, and W.P. Schleich, Entanglement versus negative domains of Wigner functions, Phys. Rev. A 74, 042323 (2006) [6] D.M. Heim, W.P. Schleich, P.M. Alsing, J.P. Dahl, and S. Varro, Tunneling of an energy eigenstate through a parabolic barrier viewed from Wigner phase space, Phys. Lett. A 377, 1822-1825 (2013)

Speaker: Prof. Wolfgang P. Schleich (Institute für Quantenphysik, Universitat Ulm)

Slides Wolfgang_Schleich.pdf

10:00 → 10:40 Quantum RMS Deviation and Heisenbergs Error‐Disturbance Relation

It has been claimed in recent research publications that Heisenberg’s idea of an accuracy-disturbance trade-off in quantum measurements has been theoretically and experimentally falsified. Here we analyze this claim and show that it is based on a combination of two factors: (a) a restricted perspective on measurement uncertainty relations that focuses on state-dependent measures of error and disturbance rather than considering them figures of merit for measuring devices; (b) the use of a generalization of Gauss’ root-mean-square deviation that is based on the problematic concept of noise operator. We present an alternative operationally significant quantum generalization of root-mean- square deviation and using this we obtain a valid formulation of a Heisenberg-type error- disturbance relation for position and momentum.

Speaker: Prof. Paul Busch

Slides Busch.pdf

10:40 → 11:00 Coffee break

11:00 → 11:30 Effective Image Recognition using High-Order Symmetry of Correlated Orbital Angular Momentum (OAM) States

A major contribution of Wigner's work was the introduction of group theory to study both the dynamics and the classification of states in quantum mechanics. The use of rotational symmetry to study the properties of angular momentum eigenstates is particularly associated with him. Following along a similar path, it is shown here that advances in the study of entangled two-photon states allow the rapid detection of rotational symmetries in complex macroscopic objects, and that knowledge of this symmetry structure can allow identification, and in some circumstances reconstruction, of the object. This suggests some possible future applications.

Speaker: Prof. Alexander V. Sergienko

Slides Alexander_V._SERGIENKO.pdf

11:30 → 12:00 Wigner crystals - New realizations of an old idea

Speaker: Prof. Jenő Sólyom (Wigner RCP of the HAS)

Slides Jenő_Sólyom.pdf

12:15 → 13:45 Lunch

14:00 → 14:40 The role of Wigner's 1939 Representation Theory in ongoing Foundational Changes of Quantum Field Theory

Presently quantum field theory is undergoing significant changes which started with the solution of an old problem: the quantum field theory behind the third positive energy Wigner representation class ("infinite spin")in terms of of string-localized generating fields. This in turn led to foundational changes for the other two classes: the m>0 and the m=0 finite helicity class The stringlocal description of these two classes leads among other things to the extension of renormalizability for any spin and the "adiabatic equivalence principle" makes sure that the physical content is the same as in the nonrenormalizable pointlike description i.e. stringlocal fields play the role of a different "field coordinatization" of the same QFT. The special case m>0, s=1 amounts to a Hilbert space analog of the BRST operator gauge description in Krein space in which the subalgebra of pointlike fields coincides with the gauge invariant observables. The stringlike approach leads to new insights into the Higgs mechanism and confinement. Last but not least it reveals that the noncompact localization properties of the third Wigner class matter as those which astrophysicists ascribe to dark matter.

Speaker: Prof. Bert Schroer

Slides Schroer_Presentation-WIII-b.pdf

14:40 → 15:20 Relativistic Wigner functions

Owing to the processes of particle creation and annihilation relativistic quantum mechanics does not exist as a consistent theory and it must be replaced by quantum field theory. Nevertheless the original construction of Wigner (and Szilard) can be extended in a natural manner to quantum field theory just by replacing wave functions by the field operators [1]. The expectation value in a one-particle state of such an object reduces in the nonrelativistc approximation to the standard Wigner function. Of course, in full quantum field theory the evolution equation for the Wigner function involves higher order functions that are built from products of more than two field operators and the hierarchy of such equations does not close. However, when the coupling to the external field plays the dominant role and the mutual interaction can be neglected, one obtains the evolution equation similar to the transport equation for the standard Wigner function that in some cases can be solved analytically. One important application of this construction is the description of electron-positron pair creation by an applied electromagnetic field. Every quantum field theory allows for the construction of the Wigner function from field operators but for the electromagnetic field (and also for other bosonic fields) there is also an entirely different construction that leads to a Wigner functional. The arguments of this functional are not points in the phase space but the electric and magnetic fields. Still, this functional shares many properties with the good old Wigner function and it enables one to learn something new about the properties of the quantized electromagnetic field. In particular, this construction gives a new insight into the statistical properties of the electromagnetic field at finite temperature. References: [1] I. Bialynicki-Birula, P. Gornicki and J. Rafelski, Phys. Rev. D 44, 1825 (1991).

Speaker: Prof. Iwo Białynicki-Birula (Polish Academy of Sciences, Warsaw)

Slides Bialynicki-Birula.pdf

15:20 → 15:40 Coffee break

15:40 → 16:20 Bell's inequalities: "From Einstein, Bell, Wigner, to entangled quantum bits: a new quantum era"

Speaker: Prof. Alain Aspect (Institut d'Optique, Palaiseau)

16:20 → 17:00 Nuclear Physics at GSI and FAIR

The international Facility for Antiproton and Ion Research in Europe (FAIR) is the largest fundamental science facility under construction worldwide. FAIR has been founded by Finland, France, Germany, India, Poland, Romania, Russia, Slovenia and Sweden. From 2018 onwards, FAIR will provide unique opportunities for cutting-edge research in nuclear, hadron and particle physics, atomic and anti-matter science, high density plasmas and applications in condensed matter, biology and the bio-medical- and material sciences. A global community of 3000 scientists from 51 countries prepare for outstanding research in the APPA, CBM, NUSTAR and PANDA detector collaborations. A cutting edge accelerator complex with eight storage and superconducting synchrotron rings and several linacs is constructed with the GSI Helmholtz Centre for Heavy Ion Research in Darmstadt, Germany.

Speaker: Prof. Horst Stöcker

17:00 → 17:40 Neutron Stars, Black Holes, and Gamma Ray Bursts: three events with Eugen Wigner in Princeton

Speaker: Prof. Remo Ruffini

Slides Budapest_ultimo_tentativo.pdf

18:30 → 22:00 Welcome Cocktail and Symposium Concert at the Instituto Italiano di Cultura

Tuesday, 12 November

08:30 → 10:10 Astrophysics

08:30 The quest for gravitational waves: Status of the current ground-based projects I.

Speaker: Prof. Jean-Yves Vinet

Slides WIGNER.pdf

08:55 The quest for gravitational waves: Status of the current ground-based projects II.

With the aim to detect gravitational waves, in the last 15 years a few large interferometers have been constructed and were operating in various Continents. This first generation has demostrated the validity of the fundamental ideas and stimulated the study for the up-grade to higher sensitivity instruments, at present under construction. The purpose of the talk is to show which level of cooperation is existing in the World wide GW community, to achieve jointly the ambitous scientific result.

Speaker: Prof. Federico Ferrini

Slides Wigner_-_GW_FF.pdf

09:20 ET: the Einstein Telescope; designing the third Generation of Gravitational Wave

Speaker: Prof. Harald Lück

Slides Lueck_ET_Wigner.pptx

09:45 Gravitational Wave Detection from Space: The eLISA Mission

More than 90 years ago, Einstein predicted the existence of Gravitational Waves as a consequence of his theory of General Relativity. They are minute distortions of space and time, created by rapidly accelerating large masses, and propagating at the speed of light. Several kilometer-size laser-interferometric gravitational wave detectors are currently operating on the earth. They will soon be joined by space detectors with armlengths of millions of kilometers, looking at the signals from massive black holes in the whole universe. The European Space Agency has recently called for the submission of science themes for the L2 and L3 large mission launch opportunities. This talk will describe the science theme „The Gravitational Universe“ and eLISA as strawman mission concept for its realization.

Speaker: Prof. Karsten Danzmann

Slides Wigner_KD_2013.pdf

08:30 → 10:10 Energetics

08:30 Eugene P. Wigners Visionary Contributions to Generations I through IV Fission Reactors

Eugene P. Wigner made instrumental advances in reactor physics, reactor design and technology, and spent nuclear fuel processing for both purposes of developing atomic weapons during world-war II and nuclear power afterwards. Wigner really came to nuclear energy through the Manhattan Project, where he could really use his talents of theorist, experimentalist and engineer. Not only his varied contributions were instrumental to the success of the Manhattan Project but they laid the foundations for key technologies, processes and reactor designs that enabled the development of Generation-I through IV fission reactors. Natural uranium fuelled graphite moderated reactors (Gen-I) were directly derived from initial weapon-grade materials production reactors. Wigner’s preference for water cooling for the sake of efficient cooling happen to lay visionary foundations to light water compact reactors that were first used to power submarines and then converted into pressurized and boiling water reactors (Gen-II). These types of reactor that essentially use 235U constitute 85% of the nuclear fleet in the world today and advanced versions that are currently commercialized (Gen-III) will remain the dominant type of nuclear power plants over the 21st century. Gen-IV nuclear systems under development today encompass a wide span of reactors and fuel cycles that are anticipated to play a role over the 21st century. Fast neutron reactors that enable using efficiently 238U that represents 99.3% of uranium gave rise to demonstration sodium-cooled reactors in major nuclear countries. A significant effort is being made in the frame of the Generation-IV Internal Forum to share visions of needed improvements in safety and economics for new generations of fast neutron reactors, be they sodium-cooled, lead-cooled or gas-cooled. Wigner’s contribution to fast reactors lies in precursor solvent-extraction methods for recovering plutonium from spent nuclear fuels and closing the fuel cycle. These examples evidence the wide span of theoretical and technological contributions that Wigner brought to all generation of fission reactors so far, in both fields of chemistry and physics, and how his spirit of skilled theorist and engineer will survive in nuclear systems anticipated for the 21st century.

Speaker: Prof. Frank Carre

Slides F_Carre_-_Wigner_111_121113_VF.ppt

08:55 The reactor ALLEGRO and the sustainable nuclear energy in Central Europe

The Visegrad-4 countries (CZ, HU, PL and SK) would like to use nuclear energy on the long run. The construction of new Generation 3+ nuclear units seems to be probable in each country belonging to this region. These reactors will provide safe and cheap electric energy approximately until the end of the 21st century. In order to use nuclear energy in the 22nd century, sustainability of fuel supply shall be achieved by applying Generation 4 breeder reactors with fast spectrum. The corresponding research and development is organized now in the framework of the V4G4 Centre of Excellence establshed by the nuclear research institutes of the region with a strong technical support of the French CEA. The most important milestone of these efforts is the start-up of the ALLEGRO reactor that shall demonstrate the viability of the gas cooled fast reactor technology.

Speaker: Prof. János Gadó

Slides Allegro_presentation_Wigner_111.pptx

09:20 Overview of EU Demo Design and R&D Studies

Speaker: Prof. Jon Harman

Slides id60_Harman_-_Wigner111_final.pptx

09:45 Progress in Magnetic Fusion and ITER

Controlled thermonuclear fusion is considered as a promising source of energy for the second half of the century. It avoids the production of greenhouse gases and offers significant advantages in the nuclear safety area. However, its availability requires the success of an important programme of research before considering an industrial development. ITER, ‘the way” in latin, is a large experiment which is the keystone of the research programme on magnetically confined plasmas. It aims at the demonstration of fusion energy at the 500MW level. Its construction, directed by an international organisation involving 35 countries, is well under way in Cadarache in the south of France. The essential physics and technology points of this research will be discussed as well as the results of the supporting research which is actively being carried out around the world.

Speaker: Prof. Jean Jacquinot

Slides JJ_Budapest_nov_2013.ppt

08:30 → 10:10 Foundations of Physics

08:30 Branched Hamiltonians and Supersymmetry

Speaker: Prof. Thomas L. Curtright (University of Miami, USA)

Slides Curtright.pdf

08:55 Deformation quantization: Quantum mechanics lives and works in phase‐space

Wigner's 1932 quasi-probability Distribution Function in phase-space, his first paper in English, is a special (Weyl) representation of the density matrix. It has been useful in describing quantum flows in semiclassical limits; quantum optics; nuclear physics; decoherence (eg, quantum computing); quantum chaos; "Welcher Weg" puzzles. It is also of great importance in signal processing (time-frequency analysis). Nevertheless, a remarkable aspect of its internal logic, pioneered by H Groenewold and J Moyal, has only blossomed in the last quarter-century: It furnishes a third, alternate, formulation of Quantum Mechanics, independent of the conventional Hilbert Space, or Path Integral formulations, and perhaps more intuitive, since it shares language with classical mechanics and illuminates the classical limit. It is logically complete and self-standing, and accommodates the uncertainty principle in an unexpected manner. Simple illustrations of this fact will be detailed.

Speaker: Prof. Cosmas K. Zachos (Argonne National Laboratory, USA)

Picture WF2state.gif

Slides zachos5wigner111.pdf

09:20 A cellular automaton perspective on the linearity of quantum mechanics

The linearity of quantum mechanics leads to the superposition principle and interference, entailing entanglement, and the enigmatic phenomena of Schrődinger's Cat and Wigner's Friend. We introduce an action principle for a class of integer valued cellular automata and obtain Hamiltonian equations of motion. Employing sampling theory, these discrete deterministic equations are invertibly mapped on continuum equations for a set of bandwidth limited harmonic oscillators, which encode the Schrődinger equation. Thus, the linearity of quantum mechanics is related to the action principle of such cellular automata and its conservation laws to discrete ones. This could have implications for the foundations of quantum mechanics and may be useful for simulations of quantum systems.

Speaker: Prof. Hans Thomas Elze (Universitá di Pisa. Italy)

Slides Elze.pdf

09:45 Newton Force from Wave Function Collapse: a Testable Emergence Time

Wigner, to illustrate the inevitable influence of environmental noise on macroscopic quantum objects, estimated that even in intergalactic space a 1cm solid looses its wave function in about 1s due to cosmic background radiation. One of the hypothetic models of quantum-classical boundary is gravity-related spontaneous wave function collapse (Diosi-Penrose model). Recently I have extended the model and propose that collapses are responsible for the emergence of the Newton force between massive objects. I identify the collapse rate, possibly of the order of 1ms, with the rate of emergence of the Newton force. A simple heuristic emergence (delay) time is added to the Newton law of gravity. No available experimetal evidence exists against it. Confirmation or refutal can be done in feasible modern Cavendish experiments with the moving source and of better time-resolution w.r.t. to the old tests. References: [1] E. Wigner: in Quantum Optics, Experimental Gravitation, and Measurement, eds. P. Meystre and M.O. Scully, Plenum, New York, 1983, p. 43. [2] L. Diósi: Phys. Lett. A377, 1782 (2013

Speaker: Dr Lajos Diósi

Slides diosi.pdf

08:30 → 10:10 Quantum Optics

08:30 Wigner function in action: Classical description of measurement back-action

We consider a double-well trap containing a BEC, assuming that the numbers of the atoms on both sides of the trap are monitored continuously using light scattering. We develop both an exact quantum mechanical simulation, including back-action from detection of the scattered light, and a classical simulation by expanding the quantum theory as powers in the inverse of the total number of condensate atoms. If the photon counts on the detectors recording the scattered light are frequent enough that the expected oscillations of the atoms between the two traps could be detected, the quantum and classical descriptions give results so similar that in practice it would be difficult to tell them apart experimentally. This holds even for atom numbers so low that the classical approach, essentially a Gross-Pitaevskii type mean field theory, is not expected to apply, provided the quantum mechanical back-action of the measurements is properly included in the classical theory.

Speaker: Prof. Juha Javanainen (University of Connecticut, USA)

08:55 Sequential quantum measurements

Speaker: Prof. János A. Bergou

09:20 Nonlocal interferometry using Schrödinger cats

Schrodinger cat states, which are quantum-mechanical superpositions of macroscopic states, are of fundamental interest in studying the boundary between the quantum and classical worlds. I will discuss a method for generating phase-entangled macroscopic coherent states using weak optical nonlinear phase shifts. These states can produce nonlocal interference effects that violate Bell’s inequality. They are also relatively robust against photon loss and decoherence, which may have practical applications in quantum cryptography.

Speaker: Prof. James D. Franson (University of Maryland, USA)

Slides Franson_Wigner_conference_slides_v1.pdf

09:45 Wigner function and probability representation of quantum states

The relation of Wigner function with fair probability distribution called tomographic distribution or quantum tomogram associated with the quantum state is reviewed. The connection of the tomographic picture of quantum mechanics with the integral Radon transform of the Wigner quasidistribution is discussed. The Wigner-Moyal equation for the Wigner function is presented in the form of kinetic equation for the tomographic probability distribution both in quantum mechanics and in the classical limit of Liouville equation. The calculation of moments of physical observables in terms of integrals with the state tomographic probability disatributions is constructed having a standard form of averaging in the probability theory. New uncertainty relations for the position and momentum are written in terms of optical tomograms suitable for direct experimental check. Some recent experimnts on checking the uncertainty relations including entropic ones are discussed.

Speaker: Prof. Vladimir Man'ko

10:10 → 10:30 Coffee break

10:30 → 12:12 Astrophysics

10:30 The LUNA experiment at Gran Sasso Laboratory

Cross sections of nuclear reactions powering stars are essential ingredients for element nucleosynthesis, energy generation and neutrino fluxes in stellar environments. The low value of such cross sections at astrophysically relevant energies prevents their measurement in a laboratory at the Earth's surface due to the unfavorable signal-to-noise ratio. The LUNA collaboration installed two accelerators in the Underground Gran Sasso National Laboratory in Italy where the cosmic background is very much reduced and measured a few key reactions of the Hydrogen burning and Big Bang nucleosynthesis. The most relevant results achieved by LUNA will be reviewed. The next step in this research field consists in the installation of a MV machine underground: the "LUNA MV" project will be described.

Speaker: Prof. Alessandra Guglielmetti

Slides guglielmetti_Wigner111.ppt

10:55 The unreasonable effectiveness of experiments in constraining nova nucleosynthesis

Classical nova explosions arise from thermonuclear ignition in the envelopes of accreting white dwarfs in close binary star systems. Detailed observations of novae have stimulated numerous studies in theoretical astrophysics and experimental nuclear physics. These phenomena are unusual in nuclear astrophysics because most of the thermonuclear reaction rates thought to be involved are constrained by experimental measurements. This situation allows for rather precise statements to be made about which measurements are still necessary to improve the nuclear physics input to astrophysical models. We review desired measurements in these environments with an emphasis on recent experimental progress made to better determine key rates.

Speaker: Prof. Anjou Parikh

Slides Parikh_Wigner111_pdf.pdf Parikh_Wigner111.ppt

11:20 The Trojan Horse Method: Recent Applications to Nuclear Astrophysics

In the last decades, impressive improvements in astronomical observations and in computational models of stellar structure and evolution have made it possible for the first time to significantly improve our understanding of energy generation and nucleosynthesis processes that take place in a variety of astrophysical sites. Nuclear reactions in such environments remain a key ingredient for the detailed description of stellar evolution and for the explanation of the abundance of the elements in the Universe. Ideally, laboratory measurements of key astrophysical reactions should be carried out at the energy of astrophysical interest, referred to as the Gamow energy region, which depends on the temperature of the stellar plasma at which a given reaction takes place as well as on the charges of the interacting nuclei [1]. For charged-particle induced reactions the cross section E) drops exponentially with decreasing centre-of-mass energy due to the hindrance of the Coulomb barrier. As a consequence, experimental measurements become increasingly more challenging and extrapolations from data at higher energies are needed So far, only a few reactions have been studied at the relevant Gamow energy region. In all other cases, extrapolations of reaction cross sections are carried out from data taken at higher energies. Secondly, the measured cross sections must be corrected for the effect of electron screening [2,3] arising from the presence of electrons in the target atoms and, possibly, in the (partly)-ionised projectiles. Because of these intrinsic limitations in the direct experimental study of nuclear reactions for astrophysics, alternative methods for determining bare-nuclei cross sections are needed. In particular, the THM has proved to be an extremely useful and versatile approach to extract nuclear reactions of astrophysical relevance which turns out to be insensitive to the screening effect and allows to determine the energy dependence of the reaction cross section in the region of astrophysical interest. The key ideas on which the method is based and the the recepy to extract data are presented . [1] C.E.Rolfs and W.S.Rodney, Cauldrons in the Cosmos, University of Chicago Press, Chicago, 1988 [2] H.J.Assembaum, K.Langanke and C.Rolfs, Z. Phys. A327, 461 (1987) [3] F.Strieder, C.Rolfs, C.Spitaleri, and P.Corvisiero, Naturwissenschaften 88, 461 (2001)

Speaker: Prof. Claudio Spitaleri

11:45 Colored condensates deep inside compact stars

Since Eugene Wigner was awarded the Nobel prize for his discovery and application of fundamental symmetry principles, particularly in nuclear and elementary particle physics, our understanding of strong interactions within quantum chromodynamics is based more than ever on these concepts. I will demonstrate how in the absence of solutions for QCD under conditions deep inside compact stars an equation of state can be obtained within a model that is built on the basic symmetries of the QCD Lagrangian, in particularly chiral symmetry and color symmetry. While in the vacuum the chiral symmetries is spontaneously broken, it gets restored at high densities. Color symmetry, however gets broken simultaneously by the formation of colorful diquark condensates. I demonstrate that a strong diquark condensate in cold dense quark matter is essential for supporting the possibility that such states could exist in the recently observed pulsars with masses of 2 $M_sun$. Further consequences of such states for the rotational and cooling evolution of hybrid stars are discussed.

Speaker: Prof. David Blaschke

Slides blaschke_talk_wigner.pdf

10:30 → 12:01 Energetics

10:30 Possible Outcome of Fusion-fission Power Plant by 2050 and beyond

Speaker: Prof. Boris V. Kuteev

10:55 Hungarian contribution to the success of ITER

Speaker: Dr Sándor Zoletnik (Wigner RCP of the HAS)

Movie ITG_turbulence_movie.mov

Slides Wigner111_Zoletnik.ppt

11:20 Energy Flow Control

Speaker: Dr Örs Legeza (Wigner RCP of the HAS)

Slides energy_flow_v04.pdf

10:30 → 12:00 Foundations of Physics

10:30 Classical and Quantum Parts in Madelung Variables

We consider the special and general relativistic extensions of the action principle behind the Schrödinger equation distinguishing classical and quantum contributions via the use of Madelung variables for the wave function field. Postulating a particular quantum correction to the source term in the classical Einstein equation we identify the conformal content of the above action and obtain classical gravitation for massive particles, but with a cosmological term representing off-mass-shell contribution to the energy-momentum tensor. In this scenario the - on the Planck scale surprisingly small - cosmological constant stems from quantum bound states with a Bohr radius a as being =3/a2.

Speaker: Dr Péter Ván (Wigner RCP of the HAS)

Slides van.pdf

10:55 Operational Geometry on de Sitter Spacetime

Traditional geometry employs idealized concepts like that of a point or a curve, the operational definition of which relies on the availability of classical point particles as probes. Real, physical objects are quantum in nature though, leading us to consider the implications of using realistic probes in defining an effective spacetime geometry. As an example, we consider de Sitter spacetime and employ the centroid of various composite probes to obtain its effective sectional curvature, which is found to depend on the probe’s internal energy, spatial extension, and spin. Possible refinements of our approach are pointed out and remarks are made on the relevance of our results to the quest for a quantum theory of gravity.

Speaker: Prof. Chryssomalis Chryssomalakos

Slides chryssomalakos.pptx

11:20 The Unreasonable Effectiveness of Supersymmetry

Speaker: Prof. Volker Schomerus (DESY, Theory Group)

Slides schomerus.ppt

10:30 → 12:10 Quantum Optics

10:30 Spontaneous photon emission in finite-sized cavities

The dynamics of spontaneous photon emission and absorption by elementary two-level systems inside cavities of finite sizes is discussed. It is shown that the influence of boundaries of these cavities on spontaneous photon emission and absorption processes can be described in a convenient way with the help of semiclassical photon path representations over a wide range of wavelengths. Thereby, in the spirit of the Feynman path integral probability amplitudes of interest are represented as sums of contributions originating from all possible photon paths inside a cavity. Thereby also repeated reflections at the boundaries have to be taken into account. It is demonstrated that these semiclassical path representations are not only a convenient theoretical tool for describing these processes reliably but also for obtaining physical insight into the intricate interplay between the elementary quantum electrodynamical phenomena of photon emission and absorption and the photonic multimode dynamics in these cavities. As an example the spontaneous photon emission process of a two-level system located in the focus of a half-open cavity with a rotationally symmetric parabolic boundary is discussed in detail and the time evolutions of the two-level system and of the resulting photon wave packet are investigated [1]. In view of current activities aiming at the realization of qantum repeaters the quantum dynamics in such half-open cavities offers interesting perspectives for coupling an elementary material qubit to the electromagnetic radiation field efficiently. References: [1] G. Alber, J. Z. Bernad, M. Stobinska, L. L. Sanchez-Soto, G. Leuchs, ’QED with a parabolic mirror’, Phys. Rev. A 88, 023825 (2013).

Speaker: Prof. Gernot Alber (University of Darmstadt, Germany)

Slides Alber.pdf

10:55 Single dopants in diamond: quantum registers and nanoscale sensors

Speaker: Prof. Fedor Jelezko (University of Ulm, Germany)

Slides Jelezko.pptx

11:20 ELI-ALPS: A Challenge and Opportunity for European, Regional and National Science

ELI-ALPS is one of the three pillars of ELI, the first large scale European laser user facility, and one of the ESFRI roadmap Research Infrastructures. ELI-ALPS, to be fully implemented in Szeged by 2018, focuses mainly on attosecond radiation sources offering beyond the state of the art beam parameters to international users. The challenge of turning contemporary research findings to a unique tool serving science and technology will be further extended at ELI-ALPS to other radiation sources spanning the spectral region between THz and x-rays, as well as to novel laser driven electron and ion sources. In my presentation I will summarize the central features of the infrastructure and highlight opportunities opened to European and regional users in conducting forefront research of scientific, technological and social interest.

Speaker: Prof. Dimitris Charalambidis

11:45 The role of the Wigner function in charged particle beam dynamics

Speaker: Prof. Renato Fedele

Slides Wigner_Budapest_2013_Talk_Fedele.pdf

12:15 → 13:45 Lunch

14:00 → 15:40 Group Theory

14:00 Poisson Geometry of Difference Lax Operators and Difference Galois Theory

We discuss the lift of Poisson structures associated with auxiliary linear problems for the differential and difference Lax equations to the space of wave functions. Due to a peculiar symmetry breaking, the corresponding differential and difference Galois groups become Poisson Lie Groups. Relations with the q-deformation of the Virasoro algebra is also described.

Speaker: Prof. Michel Semenov-Tian-Shansky

Slides Wigner111_Semenov-Tian-Shansky.pdf

14:25 Group Theory Origin of Higher Spin Duality

Speaker: Prof. Antal Jevicki

Slides Wigner112-AJevicki.pdf

14:50 Hidden symmetries of scattering amplitudes in gauge theories

Speaker: Prof. Gregory Korchemsky

Slides Korchemsky.pdf

15:15 Geometry of the nuclear shell model

The shell model has become one of the standard tools for the interpretation of nuclear properties. It exists in a variety of guises ranging from the ab initio version where all nucleons interact with each other, to more phenomenological versions with schematic interactions between nucleons in the valence shell. Shell-model calculations frequently are computationally intensive, requiring the diagonalization of large matrices, the dimension of which nowadays can reach several billion. In such situations it is always desirable to obtain qualitative insight into numerical results by alternative means. In this talk a geometry of the shell model is derived by taking the limit of large angular momentum of shell-model matrix elements. The procedure relies on the classical expressions for 3nj symbols as proposed by Wigner [1] and is reminiscent of the interpretation of nuclear matrix elements in terms of the angle between the vectors of the single-particle angular momenta, as proposed by Schiffer [2] and developed in more detail by Molinari et al. [3]. An application is presented which consists of the derivation of the shears mechanism [4] from the nuclear shell model. References: [1] E. P. Wigner, Group Theory and Its Application to the Quantum Mechanics of Atomic Spectra (Academic, New York, 1959). [2] J. P. Schiffer, Ann. Phys. (NY) 66 (1971) 798. [3] A. Molinari, M. B. Johnson, H. A. Bethe and W. M. Alberico, Nucl. Phys. A 239 (1975) 45. [4] S. Frauendorf, Nucl. Phys. A 557 (1993) 259c.

Speaker: Prof. Pieter Van Isacker

Slides isacker.pdf

14:00 → 15:40 Nuclear Physics

14:00 Nuclear Structure Aspects from Gamma‐decay from Giant Resonances

Measurements of gamma-decay from giant resonances (including the their tail regions) are important to probe in detail the properties of these states and thus to test theoretical predictions based on mean fields. This presentation focuses mainly on two aspects concerning the electric dipole excitation in nuclei. The first is the study of the low energy tail of the Giant Dipole Resonance (Pygmy resonance) using different probes to understand the nature of these high lying excited states. Some recent results obtained using the gamma detector array AGATA will be presented. The second aspect is relatated to the study of the isospin symmetry by using as a probe the gamma-decay of the GDR in thermalized systems formed with neutron evaporation reactions. Perspectives related to new planned or possible experiments will be discussed.

Speaker: Prof. Angela Bracco

Slides 000_bracco_ANGELA_WIGNER_November_2013.pptx

14:25 Interplay between Spin and Isospin in Exotic Nuclei

Nuclear physics in the 20th century succeeded in finding regularities in stable nuclei and in establishing a reasonable picture of a “nucleus”. In 1937, Wigner presented a picture, referred as “supermultiplet theory”, on a basis of deep consideration on symmetry in a proton and neutron system. We must be surprised that Wigner captured an essence of nuclear structure with little knowledge on nucleonnucleon forces. In the 21st century, experiments with radioactive nuclear beams, that have drastically developed since the 1990’s, have revealed that the picture could be valid locally, namely only in the vicinity of the beta-stability line. Now study of “exotic nuclei” which locates far from the stability line is at the forefront of nuclear physics research and has been extensively performed at RI-beam facilities in the world, such as RI Beam factory in Japan, GSI in Germany, SPIRAL2 in France, and NSCL in USA. Why can the structures of exotic nuclei be so different from those of stable nuclei? The key to understanding is “interplay between spin and isospin”. The interplay can be naturally figured out in the spirit of the supermultiplet theory when it is combined with current knowledge of nuclear forces. In the symposium, I will show the overview of experimental research of exotic nuclei at RI Beam Factory, putting emphasis on “interplay between spin and isospin

Speaker: Prof. Tomohiro Uesaka

14:50 Towards experiments at the new ELI-NP facility

The Extreme Light Infrastructure (ELI) Pan-European facility initiative represents a major step forward in quest for extreme electromagnetic fields. Extreme Light Infrastructure – Nuclear Physics (ELI-NP) is one of the three pillars of the ELI facility, that aims to use extreme electromagnetic fields for nuclear physics and quantum electrodynamics research. At ELI-NP, high power laser systems together with a very brilliant gamma beam are the main research tools. Their targeted operational parameters will be described. The related experimental areas will be presented, together with the main directions of the research envisioned. The different experiments and the instrumentation, which is designed for nuclear structure, reactions and astrophysics research, will be presented, with an emphasis of the experiments related to photo-fission studies. * This work is supported by Extreme Light Infrastructure – Nuclear Physics (ELI-NP) – Phase I, a project co-financed by the European Union through the European Regional Development Fund.

Speaker: Prof. Dimiter Balabanski

Slides balabanski_Wigner111_1113.pptx

15:15 Symmetries and in-medium effects

Chiral symmetry is a fundamental symmetry of Quntum Chromodynamics (QCD) in the limit of vanishing quark masses. In the hadronic sector chiral symmetry is broken; otherwise chiral partners – hadronic states with the same spin but opposite parity - should be degenerate in mass which is not observed in nature. It has been suggested that chiral symmetry might at least partially be restored in a strongly interacting environment. As a consequence properties of hadrons, encoded in their mass and width, may be modified in the medium. These ideas have motivated widespread theoretical and experimental activities. (For recent reviews of the field see 1-3). The talk will summarize the status of recent experimental results on the search for in-medium modifcations of hadrons in photon and proton induced reactions using the CBELSA/TAPS detector at the electron accelerator ELSA (Bonn), the Crystal Ball at MAMI (Mainz), and the HADES detector at GSI (Darmstadt). Results on the light vector mesons ρ, ω and the pesudoscalar η’ meson will be presented. References: [1] S. Leupold, V. Metag, U. Mosel, Int. J. Mod. Phys. E 19 (2010) 147. [2] R. Hayano and T. Hatsuda, Rev. Mod. Phys. 82 (2010) 2949. [3] R. Rapp, J. Wambach, H. Van Hees, Landolt Börnstein, New Series I/23A (2010) 4-1.

Speaker: Prof. Volker Metag

Slides Metag_Wigner_111_s.pdf

14:00 → 15:40 Solid Sate Physics

14:00 A first-principles description of the anomalous and spin Hall effects in disordered alloys

A theoretical description of the anomalous Hall effect (AHE) [1] and spin Hall effect (SHE) [2] based on the Kubo linear response formalism is presented giving the corresponding conductivity tensors via an appropriate form of the Kubo-Streda and Kubo-Bastin equations. The underlying electronic structure is treated using the fully relativistic multiple scattering or Korringa-Kohn-Rostoker (KKR) band structure method set up in the framework of local spin-density functional theory (LSDA). To deal with the SHE a corresponding relativistic form for the spin current density operator is used [3]. Application to disordered alloys is achieved by making use of the Coherent Potential Approximation alloy theory that in particular allows to account for the vertex corrections. Using the connection of these and the extrinsic contributions to the Hall conductivities a decomposition into intrinsic and extrinsic contributions is performed for various alloy systems. In addition the extrinsic contributions are split into skew scattering and side jump contributions via their scaling behavior. For diluted transition metal alloys, this approach leads to results in very good agreement with those obtained on the basis of the Boltzmann formalism. Using standard relations between response functions with respect to an electrical field and a temperature gradient, the scheme to calculate the AHE and SHE has been extended to deal with the corresponding anomalous Nernst effect (ANE) and spin Nernst effect (SNE) [4]. First results will be presented. References [1] S. Lowitzer, D. Ködderitzsch, and H. Ebert, Phys. Rev. Letters 105, 266604 (2011) [2] S. Lowitzer, M. Gradhand, D. Ködderitzsch, D. V. Fedorov, I. Mertig, and H. Ebert, Phys. Rev. Letters 106, 056601 (2011) [3] S. Lowitzer, D. Ködderitzsch, and H. Ebert, Phys. Rev. B 82, 140402(R) (2010) [4] S. Wimmer, D. Ködderitzsch, K. Chadova and H. Ebert, arXiv:1306.0621v1, (2013)

Speaker: Prof. Hubert Ebert

Slides Ebert.pdf

14:25 The Fermi surface of PdCrO2

Geometrically frustrated magnetic materials exhibit complex magnetic order and the influence of this frustration (amongst localised spins) on the more delocalised electrons can lead to strongly correlated behaviour. The triangular antiferromagnet PdCrO$_{2}$ is an example of a frustrated metallic magnet. Having the delafossite structure (which consists of alternately stacked layers of Pd and Cr triangular lattices), the Cr spins are expected to order in a 120$^{\circ}$ spin structure with a $\sqrt{3} \times \sqrt{3}$ periodicity below the N\'eel temperature of 37.5 K. A study of the paramagnetic Fermi surface of PdrO$_{2}$ will be presented, based on experimental measurements using Compton scattering in conjunction with first-principles electronic structure calculations. These results will be discussed in the context of measurements made in the low temperature antiferromagnetic phase by angle-resolved photoemission and the de Haas-van Alphen effect.

Speaker: Prof. Stephen Dugdale (University of Bristol, UK)

Slides Dugdale.pdf

14:50 Chiral asymmetry in nanomagnetism

The asymmetric exchange interaction, discovered by Dzyaloshinsky and Moriya at mid of the last century, has long been known in bulk systems, e.g., in context to weak ferromagnetism. Only recently, the rapidly developing research of magnetic nanostructures revealed many novel and challenging consequences of the DM interactions, such as the homochirality of domain walls, the chiral asymmetry of spin-waves, the formation of long range magnetic patterns and skyrmion states in ultrathin films, as well as the exchange bias at spin-flop coupled antiferromagnet-ferromagnet interfaces. In particular, it will be demonstrated how first principles calculations help to explore this emerging field of nanomagnetism.

Speaker: Prof. Laszlo Szunyogh

Slides Szunyogh.pdf

15:15 Recent Advances in the Korringa‐Kohn‐Rostoker Green Function Method

Similar to the historical Wigner-Seitz (cellular) method for the solution of the Schroedinger equation in solids, the all-electron full-potential Korringa-Kohn-Rostoker (KKR) Green function (GF) method uses a partitioning of space into atomic (Wigner-Seitz) cells. However, instead of wave-function matching at the cell boundaries, the KKR-GF method is based on the direct solution of integral equations where the integral kernel is given as the product of the Green function of suitably chosen reference system and the electronic potential difference between the system of interest and the reference system. In my talk I will show how a repulsive reference system and the complex-energy charge-density integration method can be exploited to achieve density-functional calculations with a computational effort that increases only linearly with N, the number of atoms in the system, thus avoiding the computational bottleneck of standard density-functional calculations where the effort increases with the third power of N. I will demonstrate that our newly developed code can be applied to systems with thousands of atoms and that it achieves a high computational efficiency even if many thousand computing cores are used. I will also present two recent numerical advances concerning the accuracy of KKR-GF calculations. I will show how density-functional total energies can be obtained with computational errors smaller than tenths of millielectron-volts per atom and how accurate charge densities can be determined even in close vicinity to the nuclear sites by a novel numerical technique for the irregular coupled radial scattering solutions that are necessary to guarantee the correct analytical Green function behaviour in the complex energy plane.

Speaker: Prof. Rudolf ZELLER

14:15 → 14:30 Megnyitó/Opening: Wigner öröksége

14:30 → 15:40 Wigner Jenő: Sokoldalú tudós a viharos 20. században

Wigner Jenő Budapestről indult, Németországban vegyészmérnöki diplomat szerzett, majd kiváló elméleti fizikus lett. A náci hatalomátvétel után az Egyesült Államokban kötött ki, ahol elméleti fizikusként és a világ első nukleáris mérnökeként is működött. Segítette új hazáját és a szabad világot az első atomreaktorok megépítésében, a 2. világháború, majd a hidegháború megnyerésében. Alkalmazta a csoportelméletet és általában szimmetriameggondolásokat a kémiai reakciók leírásában és az atomfizikában. 1963-ban fizikai Nobel-díjjal tüntették ki. Az előadás bemutatja Wigner kontinenseken és diszciplínákon keresztülívelő munkásságát és emberközelségbe hozza ezt a különleges tudóst. Eugene P. Wigner Jenő moved from Budapest to Germany, graduated as chemical engineer, and became an internationally renowned theoretical physicist. After the Nazi takeover, he moved to the US where he worked as a professor of theoretical physics and the world’s first nuclear engineer. He assisted his new home country in developing the atomic bombs, winning World War II and the Cold War. He applied group theory and symmetry considerations in the description of chemical reactions and in atomic physics. In 1963, he received the Nobel Prize in Physics. This public lecture presents Wigner’s activities that spanned continents and scientific disciplines and bring this great scientist into human proximity. The presentation will be copiously illustrated with captions in English and will include a segment from a video conversation of Wigner with Clarence Larson in 1986 in English. Irodalom/Bibliography: Hargittai István, Az öt világformáló marslakó (Budapest: Vince Kiadó, 2006). Istvan Hargittai, The Martians of Science: Five Physicists Who Changed the Twentieth Century (New York: Oxford University Press, 2006 hardcover; 2008 softcover).

Speaker: Prof. István Hargittai (Budapesti Műszaki és Gazdaságtudományi Egyetem)

15:40 → 16:00 Coffee break

16:00 → 17:00 Group Theory

16:00 Wigner and the groups in classifying elementary particles and nuclear states

Wigner did a pioneer work in the application of group theory in physics [1]. He made especially great contributions to the particle and nuclear physics [2]. The essential role of the representations of the inhomogeneous Lorentz group in classifying the elementary particles [3] is well known: a particle (fundamental or composite) transforms according to an irreducible representation. His U{ST}(4) symmetry of the spin-isospin space [4] played a very important role in finding the classification of the nuclear states. A direct consequence is the supermultiplet scheme of the internal degrees of freedom. An indirect, but equally important one, is that it served as a prototype of the dynamical symmetries, invented later on for similar purposes. The nucleus is a many-nucleon system, which can be described only with simplifying models. From structural viewpoint the basic models are the shell, the collective and the cluster models. One has to understand, how they are related to each other, what is their common intersection, and what kind of nature the specific states have. In 1958 the answer was found in terms of the U(3) group [5]. This is the symmetry of a state in the real 3 dimensional space, and togeteher with the U{ST}(4) it characterizes the wavefunction completely. From the shell model basis this symmetry selects the collective states of rotation [5], as well as the clusterization [6,7]. Elliott's U(3) group refers to a single major shell problem. Later on several algebraic models (with well-defined symmetry properties) have been invented for the description of the nuclear structure. Based on their comparison [8] the U(3)xU(3) dynamical symmetry seems to be appropriate for revealing their interrelations and for classifying the nuclear states of multi-major-shell excitations. In this contribution we discuss the similarities and the differences of the two classification schemes: the particle and the nuclear ones. [1] E.P. Wigner, Grouppentheorie und Ihre Anwendung auf die Quantenmechanik der Atomspektren, Braunschweig, F. Vieweg und Sohn, 1931. [2] E.P. Wigner, Nobel Lecture, 1963. [3] E.P. Wigner, Ann. Math. 40, 149 (1934). [4] E.P. Wigner, Phys. Rev. 51, 106 (1937). [5] J.P. Elliot, Proc. Roy. Soc. A245, 128; 562 (1958). [6] K. Wildermuth, Th. Kanellopoulos, Nucl. Phys. 7, 150 (1958). [7] B.F. Bayman, A. Bohr, Nucl. Phys. 9, 596 (1958/59). [8] J. Cseh, in preparation.

Speaker: Prof. József Cseh

Slides csehj_wigner.pdf

16:25 Describing pair production in inhomogeneous external fields with the Dirac-Heisenberg-Wigner formalism

Speaker: Mr Dániel Berényi (MTA Wigner FK RMI, ELTE)

Slides berenyi.ppt

16:00 → 17:00 Nuclear Physics

16:00 Polyakov loop and charge fluctuations as probes of QCD phase transition

We discuss the properties of the Polyakov loop and baryon number fluctuations as probes for the deconfinement and the chiral phase transition in QCD. The arguments will be presented in the context of Lattice QCD and an effective chiral model calculations based on the functional renormalisation group. We connect theoretical findings with experimental data.

Speaker: Prof. Krzystof Redlich

Slides Redlich_Wigner.ppt

16:25 QGP Hadronization: Universal Conditions at SPS, RHIC and LHC

We study properties of the expanding quark-gluon plasma (QGP) fireball and the principles governing QGP hadronization, employing the statistical hadronization model (SHM) description of particle production in relativistic heavy-ion collisions. We show that the chemical non-equilibrium model gives a very good description of the hadron production in entire energy range including the LHC Pb-Pb collisions at 2.76 TeV. The SHM model parameters assume expected values, and the quark-gluon plasma fireball beaks-up at a universal hadronization condition. The fireball bulk properties to vary significantly are the reaction volume and degree of strangeness phase space saturation. There are small variations of energy density and pressure of the fireball at hadronization, compatible with the expected expansion dynamics of the fireball.

Speaker: Prof. Johann Rafelski

Slides Rafelski.pdf

16:00 → 17:00 Solid Sate Physics

16:00 Magnetic materials modelling ab-initio: fluctuating Wigner-Seitz cell magnetic moments, electron scattering resonances and strong electron correlations

Density functional theory (DFT) is extensively used in ab-initio materials modelling. This can be extended by identifying different time scales amongst the collective electronic degrees of freedom. For example, magnetic excitations, which trigger the loss of magnetic order in a magnet with rising temperature, are described by attaching to all Wigner-Seitz cells in a solid local spin-polarisation axes, whose orientations vary very slowly on the time-scale of cell-to-cell electronic propagation [1]. Averaging over these `local moment' degrees of freedom provides a quantitative description of the type and onset of magnetic order, high temperature paramagnetic phases and indeed magnetic phase diagrams. We illustrate this disordered local moment (DLM) theory of finite temperature magnetism with recent work on CoMnSi metallic metamagnets [2]. For many magnetic materials the standard DFT treatment of electron exchange and correlation is inadequate and better approximations are required. One such improvement, the local-self-interaction correction LSIC [3], captures strong electron correlation effects via its focus on the Breit-Wigner type resonant scattering of d- and f- electrons. Here a brief overview of how this theoretical approach has been incorporated into the DLM theory will be given [4] and results shown for the transition metal oxides Mn0, FeO, Co0 and NiO which have anti-ferromagnetic order at low T. We will show how the DLM-LSIC picture solves the puzzle of the large insulating gap persisting into the paramagnetic state [5]. [1] B.L. Gyorffy et al., J.Phys. F 15,1337, (1985). [2] J.B. Staunton et al., Phys. Rev. B 87, 060404(R), (2013). [3] M. Lueders et al.,Phys. Rev. B 71:205109, (2005). [4] I.D. Hughes et al., Nature, 446, 650-653, (2007). [5] I. D. Hughes et al., New J. Phys. 10, 063010, (2008).

Speaker: Prof. Julie Staunton

16:25 Identification and characterization of solid-state single photon emitters

Speaker: Dr Ádám Gali (Wigner RCP of the HAS, BME)

Slides Gali.pdf

16:00 → 16:40 Wigner Jenő a fasori diák - Eugene P. Wigner, Pupil of a Legendary School

“Naturally, we learned Physics from Sándor Mikola.” Wigner recalled. “I am proud to say that after two years of study (under his guidance at the Budapest Lutheran Gymnasium), the physics courses at the Budapest University of Technical Sciences (Műegyetem) and the Berlin Technische Hochschule seemed to be almost mere repetition.” “Never will I forget my former teachers, among them teacher of mathematics László Rátz , a genuine peadagogue and warmhearted man, who first awoke in me a love for his subject.” --­Wigner wrote. We introduce during the lecture Wigner’s school years, his dearest teachers and his secondary school itself –the Budapest Lutheran (“Fasori”) Gymnasium—which compares well with the achievements of the Bronx High School of Science in the United States, New York.

Speaker: Prof. László Kovács

Slides Wigner_Jenő,_a_fasori_diák_MTA.pptx

Video kovacs_l.avi wigner2.avi

17:00 → 19:00 Poster Session

Wednesday, 13 November

09:00 → 09:40 Multi-entanglement of a Single Particle

Speaker: Prof. Helmuth Rauch

Slides 13-Wigner.ppt

09:40 → 10:20 Poincaré Sphere and a Unified Picture of Wigners Little Groups

Speaker: Prof. Young Suh Kim

Slides kim.pdf

10:20 → 10:30 Information on the Wigner Memorial Tour (14th November)

10:30 → 11:00 Coffee break

11:00 → 11:40 E. P. Wigner and the Shaping of a National Laboratory: From the Manhattan Project to the Present

The modern Oak Ridge National Laboratory (ORNL), which is the largest of the US Department of Energy (DOE) research laboratories, had its origins in the Manhattan Project as a pilot-scale facility for the production and separation of plutonium. Although E. P. Wigner spent only a little more than a year as research director of what was then known as Clinton Laboratories, his influence on the development of ORNL extended far beyond that period. Indeed, it was Wigner who laid the foundations for many of the signature strengths that ORNL boasts today, including nuclear energy, materials and chemical sciences, neutron scattering, life sciences and arguably computational science. When discussing Wigner’s lasting impact on ORNL, it is useful to consider a series of somewhat distinct periods: Wigner pre-Clinton – the Manhattan Project and the Metallurgical Laboratory at the University of Chicago; Wigner at Clinton – his role in developing and implementing a vision for a post-war civilian nuclear research laboratory underpinned by fundamental science; Wigner after Clinton – his continuing engagement with ORNL as consultant to and friend of ORNL’s longest serving director, Alvin Weinberg; and Wigner as ORNL’s “patron saint” and the inspiration for the establishment of the prestigious Wigner Fellowships for outstanding early-career researchers and most recently for the establishment of the “Eugene P. Wigner Distinguished Lecture Series,” which brings Nobel Laureates and internationally known industrial and technical leaders to the laboratory. In dealing with these periods we will refer to much original material that will convey Wigner’s most enduring legacy: that not only is basic science a matter of joy to the individual scientist, but it can and should contribute to the well-being of humanity.

Speaker: Prof. Malcolm STOCKS

Slides Wigner-ORNL_1311_Final.pdf

11:40 → 12:20 The First and Best Reactor Engineer

Speakers: Prof. József Rónaky, Prof. László Koblinger

Slides Wigner_KL.ppt

12:30 → 13:45 Lunch

14:00 → 14:40 Fractional and Majorana Fermions (The physics of Dirac zero-energy modes)

Speaker: Prof. Roman Jackiw

Slides Budapest-Wigner_Roman_Jackiw.pdf

14:40 → 15:20 Carbon from Red Giants to White Dwarfs The Breit-Wigner Formula, the Wigner Limit, and the Wigner-Seitz Radius

This talk will discuss on to key reactions during post-main sequence stellar evolution. Both the radiative capture reactions 12C(α,)16O and the fusion reaction 12C+12C affect the nucleosynthesis of carbon in our universe. The role of these reactions will be discussed and recent results for the reaction cross sections will be analyzed in the context of nuclear structure and reaction models formulated by Eugene Wigner. The impact of the present prediction on quiescent late stellar evolution and cataclysmic explosions will be discussed.

Speaker: Prof. Michael Wiescher

Slides Wigner_111_Wiescher.pptx

15:20 → 15:40 Coffee break

15:40 → 16:20 Broken Symmetries and the Higgs Boson

The Standard Model, the theory of particle physics, based on global and local gauge symmetries, was established 40 years ago and it seems to describe all experimental data very well. All of its elementary particles were identified and studied long ago apart from the Higgs boson. The two main experiments of the Large Hadron Collider at CERN, CMS and ATLAS in 2012 observed a new boson with properties close to those predicted for the Standard Model Higgs boson. The latest LHC results imply that the new boson is indeed the Standard Model Higgs boson and thereby prove the validity of the Brout-Englert-Higgs mechanism of spontaneous symmetry breaking. François Englert and Peter Higgs received the 2013 Nobel Prize in physics. There are several questions yet concerning the possible theoretical significance of the mass of the new particle.

Speaker: Prof. Dezső Horváth (Wigner RCP of the HAS)

Slides wigner111_broken_symm.pdf

16:20 → 17:00 Eugene Wigner: A Gedanken Pioneer of the Second Quantum Revolution

Eugene Wigner pointed out very interesting consequences of Quantum Physics in elegant gedanken experiments. Due to technical progress these gedanken experiments have become real experiments and contribute to the development of novel concepts in quantum information science, often called the second quantum revolution.

Speaker: Prof. Anton Zeilinger (Universität Wien, Wien, Austria)

17:00 → 17:20 Closing

Convener: Dr Peter Levai (MTA KFKI RMKI)

18:00 → 21:00 Night Cruise on the River Danube

18:30 Eugene P. Wigner's Wisdom

Eugene P. Wigner had a decisive impact on my scientific career. We first exchanged letters in 1964; my first ever publication in 1964 was a response to one of his papers. In 1969, we met, and he gave me extensive tutorials about the utilization of the symmetry concept in physics and chemistry. Wigner was one of the five so-called „Martians,” a loosely defined group of world-renowned Jewish-Hungarian-American scientists who were willing to risk their scientific careers in order to address themselves to the defense of the United States and the Free World during World War II and the ensuing Cold War. Wigner was a chemical engineer by training, but became a theoretical physicist, first in Berlin, then at Princeton University. He applied the symmetry concept, and in particular group theory, in the description of chemical reactions and in nuclear physics. In 1963, he was awarded the Nobel Prize in Physics. Eugene P. Wigner and István Hargittai in 1969, in front of the old physics building at the University of Texas at Austin Wigner was active in mobilizing science and his fellow scientists for defense-related research even before World War II started and he played a role in initiating the Manhattan Project. He participated in building the atomic pile of the Metallurgical Laboratory at Chicago University. He became the world’s first nuclear engineer and played a pivotal role in developing the Hanford reactors for the production of plutonium. After World War II, for a couple of years, he was the scientific director of Oak Ridge National Laboratory, after which he returned to theoretical physics at Princeton University. Politically he was conservative and a dedicated advocate of civil defense. The above is a very sketchy outline of Wigner’s well-known path. My presentation will focus on less known aspects of Wigner’s life and oeuvre. Bibliography: Istvan Hargittai, The Martians of Science: Five Physicists Who Changed the Twentieth Century (New York: Oxford University Press, 2006 hardcover; 2008 softcover).

Speaker: Prof. István Hargittai

Thursday, 14 November

09:00 → 10:00 Wigner Memorial Tour to the 'Fasori' Lutheran Secondary School

10:00 → 11:30 Scientific Tour nearby the 'Fasori' Lutheran Secondary School

11:30 → 12:00 Transport to the Wigner RCP of the HAS and the Wigner Datacenter

12:00 → 12:30 Visit of the Wigner Datacenter

12:30 → 12:50 Welcome by the Chairs

12:50 → 14:00 Reception at the Panoramic Conference Room

14:00 → 14:15 Pre-Inauguration of the Wigner Square