COLLOQUIUM IN HONOR OF VALERIJ BOČVARSKI

Belgrade 13^th – 14^th October, 2017

Forbidden to all those who ignore Geometry

Prof Valerij BOČVARSKI died last year. His whole active life has been devoted to research and teaching both in Physics and Philosophy. The above Greek sentence, which was written at the entrance gate of Plato’s Academy, ideally symbolises this activity.

In honour of this outstanding researcher and teacher, whose interests covered a tremendously wide field, we plan to organize this year a two day colloquium, on 13^th October at the Institute of Physics- Belgrade (IPB) (http://www.ipb.ac.rs/index.php/en/) and Institut Français de Serbie (IFS) (http://www.institutfrancais.rs/sr/ ) and on 14^th October, at IPB. This colloquium is aimed at gathering researchers, teachers and students interested in a variety of physical and philosophical questions.

The topics can be summarized as follows:

Physics:

- Electron-atom (molecule) collisions

- Atom-atom (molecule) collisions at thermal energy

- Stern-Gerlach atomic interferometry: principle and applications

- Expert systems for the treatment of collisional spectra

Philosophy

- The concept of Morphology

- Morphology of Physics (extremum principles, discrete and continuous worlds, space and time)

- Morphology of Beauty (Art versus Science)

There is no registration fee, but the participants are kindly ask to cover their own accommodation and travel costs.

Forthcoming information will be found on links http://valerij-bocvarski.weebly.com/ and web page https://mail.ipb.ac.rs/~centar3/bocvarski.html

Secretaries: - In Belgrade: Dr. Bratislav Marinković <bratislav.marinkovic@ipb.ac.rs >

- In Paris; Prof Jacques Baudon <jacques.baudon@univ-paris13.fr >

P r o g r a m m e

13^th October, Friday

Venue : Institute of Physics (IPB), Pregrevica 118, Zemun,

lecture hall “Zvonko Maric”

10:30 – 10:45 Opening words from – Dr. Aleksandar Bogojević, Director of the Institute of Physics Belgrade and Dr. Bratislav Marinković

10:45 – 11:30 Prof. Jacques Baudon, Laboratoire de Physique des Lasers - Université Paris 13

LEGACY OF PROF. VALERIJ BOČVARSKI

The legacy that Valja Bočvarski leaves us covers a wide variety of domains, including teaching (at University of Kragujevac), research in experimental physics (collision physics) and, last but not least, philosophy (concept of morphology). We shall try to evidence the great originality - a bench mark of all Valja’s activities - appearing in these different fields.

11:30 – 11:45 Coffee break

11:45 – 12:15 Dr. Francisco Perales, Laboratoire de Physique des Lasers - Université Paris 13

LOW ENERGY COLLISIONS OF SPIN-POLARIZED METASTABLE ARGON ATOMS WITH GROUND STATE ARGON ATOMS

The collision between Ar* (3p⁵4s, ³P₂, M=+2) slightly decelerated by the Zeeman slower-laser technique and a co-propagating Ar (3p⁶, ¹S₀), both merged from the same supersonic beam, but coming through adjacent slots of a rotating disk, is investigated at center-of-mass energies ranging from 1 to 10 meV. At these sub-thermal energies, the "resonant metastability transfer" signal is too small to be evidenced by time of flight spectra. Nevertheless, excitation transfers are expected to increase significantly at much lower energies as suggested by previous theoretical predictions of potentials 2g (³P₂) and 2u (³P₂). Limits at ultra-low collisional energies will be also discussed. The experimental method is versatile and could be applied to Krypton where numerous isotopes are available.

12:15 – 12:45 Dr. Mirjana Božić, Institute of Physics Belgrade

QUANTON INTERFERENCE

In 1973 Bunge coined the term “quanton” to express the fact that objects in the quantum world, like electrons, neutrons, atoms, protons, molecules, photons, have properties which look strange and escape unanimous theoretical description. Interference, as a process of accumulation of arrivals of individual quantons to the screen/detectors in an interferometer, has been for decades in the center of studies aimed to understand how particle like and wave like properties of quantons are interrelated. In this talk we shall present how atomic interference experiments, realized by Valerij Bočvarski and physicists in the Laboratoire de Physique des Lasers in Paris, contributed to these studies. We shall present also the unified interpretation of interference of quantons which is based on the de Broglie-Bohm trajectories of massive particles and photon trajectories determined by the electromagnetic energy flow lines.

12:45 – 13:15 Dr. Iztok Čadež, Institute "Jože Štefan", Ljubljana, Slovenia

LABORATORY FOR ELECTRON–ATOM COLLISIONS, IOP BELGRADE AND INITIAL COLLABORATION WITH THE LPOC, UNIVERSITÉ PARIS VI IN EARLY SEVENTIES

Short overview will be presented of the atmosphere and activities in the laboratory for electron-atom collisions at the Institute of Physics in Belgrade at the time when Valja joined us. Also, initial collaboration with former Laboratoire de physique et optique corpusculaires at the Université Paris VI in early seventies will be described. There I first met prof. Jean Reinhardt with whom Valja collaborated later and eventually developed deep friendship.

13:15 – 15:00 Lunch for the speakers at the restaurant of IPB provided by IPB

15:00 – 16:00 Free time and commuting to downtown

Venue : Institut Français de Serbie (IFS) à Belgrade, Zmaj Jovina 11

16:00 – 16:15 Welcome – M. Bertrand Millet, Attaché de coopération

16:15 – 17:00 Prof. Jacques Baudon, Laboratoire de Physique des Lasers - Université Paris 13

MORPHOLOGIE DE LA PHYSIQUE (Editions Edilivre, 2015)

The basic idea of morphology is that, since the coming of Homo Sapiens, the thought and the logics govern the whole human intellectual activity, whatever the period under consideration. This will be illustrated by the historical development of the “natural science”, since the Ancient Greeks to nowadays. In particular the contradictory concepts of discrete (cf. Zeno) and continuous (cf. Descartes) worlds will be examined in some detail.

17:00 – 17:30 Prof. Byron Kaldis, Department of Humanities, Social Sciences and Law, The National Technical University of Athens, Greece

HISTORY LESSONS FOR THE EPISTEMOLOGY OF PHYSICS

The talk attempts to show on the basis of some historical cases of path-breaking advances in physics, mainly from the turn of the previous century, that physics has developed historically on the basis of clearly identifiable epistemological choices made on the part of the protagonists (along with some contingent factors of societal or economic nature).

17:30 – 17:45 Coffee break

17:45 – 18:15 Prof. Nigel Mason, Open University, Milton Keynes, U.K.

LITTLE THINGS MAKE BIG THINGS HAPPEN

Atoms and molecules are small, very small, surely they can’t affect our everyday life? Yet from when we awake in the morning until we turn off the light at night, the very small world of the atom and molecule influences all that we do. In this talk I will take you on a journey through your day revealing how atoms and molecules control the way we live. 'It's the little details that are vital. Little things make big things happen.' John Wooden.

18:15 – 18:45 Dr. Bratislav Marinković, Institute of Physics Belgrade

ELECTRON ATOM COLLISION EXPERIMENTS AND DATABASES

Experimental methods and set-ups developed in the Laboratory for Atomic Collision Processes (LACP), Institute of Physics Belgrade (IPB) are presented, together with the results for elastic and inelastic electron scattering by atomic targets. Determination of absolute values for differential cross sections (DCS) is discussed. Information System (IS) in the physics of atomic collision processes has been developed based on the data related to the existing measurements in our Laboratory.

18:45 Closing Day 1

Dinner in downtown (individual)

14^th October, Saturday

Venue Institute of Physics (IPB), Pregrevica 118, Zemun

Library reading room “Dr. Dragan Popovic”

10:30 – 11:00 Dr. Violeta Petrović, Institute of Physics, University of Kragujevac

EXPERT SYSTEMS FOR THE TREATMENT OF COLLISIONAL SPECTRA

We developed couple expert systems for discrete spectra analysis obtained in the electron method spectroscopy experiments which consist in detection of very low energy electrons formed in electron - atom (molecules) collisions: expert system for threshold spectra analysis of He atom, and N2 and SO2 molecules. Although both atomic and molecular spectra are discrete, important difference among them lies in the phenomenon of vibrational states, which are present in molecules.

11:00 – 11:30 Prof. Miroljub Dugić, Institute of Physics, University of Kragujevac

A MINIMALIST APPROACH TO QUANTUM TIME: TOWARDS “QUANTUM INDIVIDUATION”

A sketch of the arguments for non-fundamental character of the standard “universal” physical time and the notion of the novel concept of Local Time (LT) will be briefly presented. Then “quantum individuation” stemming from the LT Scheme will be crossed with the favorite subject of prof. Valerije (Valja) Bocvarski – of Morphology of Physics in the sense of ‘every instant of time a new universe’ – the latter being my understanding of Valja’s arguments presented in our numerous “quarrels” about the meaning of quantum theory.

11:30 – 11:50 Coffee break

11:50 – 12:20 Prof. Vladimir M. Ristić, Institute of Physics, University of Kragujevac

ZENO AND DESCARTES INFLUENCE ON THE EXPERIMENTAL METHOD IN PHYSICS

We are comparing Greek and modern methods of research, and finding that after giving identical answers to Ontological and Gnosio-Ontological postulates, the two thoughts are going apart in answering to Interaction-Existence postulate. Greeks gave priority to existence, while modern thought considers interaction to be primary. This results in two formulations of causality: Greek thought – Every object has its cause; Modern thought – Every change of the state of object has its cause. Using this analysis, we show that modern thought through Quantum Mechanics is going back to Greek approach. So, it seems that modern method of research closes the cycle. But examining differences of the two thoughts, concerning experimental approach we show also that in Quantum Mechanics two approaches are parallel, leaving the question open.

12:20 – 12:50 Dr. Ivan Petrović, Technical College of Applied Studies Kragujevac

EXPERT SYSTEMS: METHODOLOGY AND REALISATION

Expert system we define as a computer program that has expert level knowledge about a particular domain and knows how to use it in order to solve problems which cannot be solved (easily and enough fast) by using classical procedural programs. It consists of the following three main components: knowledge base, inference engine and user interface. For the methodology, the most important is inference engine which contains the production rules with characteristic if-then-else form. Here it can be found the link between Aristotle’s logic and computer science today.

12:50 – 13:20 Prof. Nigel Mason, Open University, Milton Keynes, U.K.

ATOMIC AND MOLECULAR SCIENCE AND THE NEED FOR DATA

Our need to understand the natural world from stars and planets to the origins of life and to be able to develop the technologies that control our lives (from medicine to lighting) requires a detailed knowledge of atomic and molecular science. How can we collate all the data necessary to study and explore all of the different scientific and technology challenges we face today? In this talk I will review how atomic and molecular science meets big data and how, in future, we will come to rely on computational infrastructures and artificial intelligence to determine how we develop our society.

QUANTUM CONTROL OF CHEMICAL REACTIONS ACHIEVED WITH ELECTRONS

13:20 – 13:30 CLOSING OF THE WORKSHOP

13:30 – 15:00 Lunch for the speakers at the restaurant of IPB provided by IPB

GALLERY IN MEMORIAM

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