Warsaw Colloquium for Theoretical Physics – CFT PAN – Centrum Fizyki Teoretycznej Polskiej Akademii Nauk

Simulating quantum many-body systems with classical and quantum computers

cft — Wed, 06 Aug 2025 20:50:25 +0000

Understanding and applications of quantum Hall effects

cft — Wed, 06 Aug 2025 20:40:30 +0000

In the talk I will present the role played by charges and magnetic impurities in the topological physics of quantum Hall effects. I will also mention the application of quantum macroscopic phenomena in solids to high-precision metrology. Finally, I will address the speculative question of whether the redundancy of quantum effects and host materials can reveal new physics, so far sought in expensive high-energy colliders.

Photon: A Very Peculiar Elementary Particle

dev — Fri, 27 Dec 2024 12:19:37 +0000

In my talk I will show that photons have properties which set them apart from all other elementary particles. These properties are quite intriguing but they are never mentioned in textbooks on quantum electrodynamics.

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This is a hybrid event:
Auditorium of the Institute of Physics PAS, Al. Lotników 32/46

Online: Zoom Link, (Passcode: 134595, Meeting ID: 823 8038 0442)

Attoscience, Nobel 2023 and Quantum Simulators

dev — Fri, 27 Dec 2024 12:19:37 +0000

I will start my talk with an introduction to „super-intense laser-matter physics”. I will then focus on the phenomenon of High Harmonics Generation (HHG) and its physical nature. I will explain how this phenomenon may lead to generations of attosecond pulse trains or isolated attosecond pulses in XUV range. In the second part, I will focus on recent developments in the field that allow to study QED aspects of attophysics. The third part will be devoted to the discussion of quantum simulators of atto-physics with ultracold atoms. I will end with my personal story of Nobel 2023.

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This is an onsite event:
Auditorium of the Institute of Physics PAS, Al. Lotników 32/46

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Beyond quantum Markovian semigroups

dev — Fri, 27 Dec 2024 12:19:37 +0000

In most realistic situations a quantum system is never perfectly isolated and has to be considered as an open quantum system: it is coupled to an environment that induces decoherence and dissipation. These phenomena can not be described within the standard Schroedinger unitary evolution. In my talk I provide a basic introduction to Markovian semigroups stressing the very concept of complete positivity which plays a key role in modern quantum information theory being a mathematical representation of a quantum channel. However, quantum systems cannot always be described within a Markovian semigroup, which requires a large separation of system and environment time scales. I discuss basic concepts of non-Markovian evolution which are illustrated with simple physical models. Finally, I discuss a natural connection to quantum stochastic processes and the property of Markovianity and classicality.

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This is a hybrid event:

Room D, the Institute of Physics PAS, Al. Lotników 32/46

Online: Zoom Link, (Passcode: 134595, Meeting ID: 823 8038 0442)

Coral Skeletons: the Interplay between Crystallographic Processes and Cellular, Physiological Mechanisms

dev — Fri, 27 Dec 2024 12:19:37 +0000

One of the fundamental questions regarding the functioning of living organisms pertains to the extent to which their functions, tissue organization, and the formation of skeletal structures are influenced by physicochemical factors from the external environment, versus the extent to which they are controlled by the organism’s internal environment, with a predominant influence of internal physiological regulation. This seminar will outline the aforementioned issues using corals as an example, given their role as builders of coral reefs and as inhabitants of the deepest oceanic depths. The macromorphology of coral skeletons is considered to be a highly sensitive recorder of environmental changes: corals forming colonies exhibit significant morphological plasticity in response to local variations in light availability, water flow dynamics affecting sedimentation, and the transport of food particles. Some of these aspects can be modeled in silico, and a few potentially interesting aspects will be presented as potential collaborative proposals. Until recently, the microscale organization of the skeleton was mainly viewed as an outcome of purely physicochemical crystallization of calcium carbonate. However, recent years have seen a complete shift in the paradigm of calcification mechanisms, which are now recognized as predominantly physiological processes.

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This is an onsite event:Auditorium of the Institute of Physics PAS, Al. Lotników 32/46

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Dimensions of Life

dev — Fri, 27 Dec 2024 12:19:37 +0000

Recent debate between two distinguished astrophysicists on the relation between the anthropic principle and origin of life held in the journal of general circulation Gazeta Wyborcza as well as in the just published book rings the bell of the XIX century debates on the relation between science and religion. 15 years ago I published an article on the same issue underlying the fact ignored in recent debates, namely the relation between the laws of evolution and the laws of physics.

In this lecture I shall address that issue again, choosing as example the universal law of evolution describing relation between the metabolic rate and organism growth rate and discuss the following conclusion on the origin of terrestrial life showing the drastic difference with the above mentioned debate on the interpretations of the anthropic principle.

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This is an onsite event only:

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Auditorium of the Institute of Physics PAS, Al. Lotników 32/46

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Entangled photons in a weak gravitational field

dev — Fri, 27 Dec 2024 12:19:37 +0000

I will present an ongoing effort to measure how entangled pairs of photons respond to the gravitational field of the Earth.

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This is an onsite event only:

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Auditorium of the Institute of Physics PAS, Al. Lotników 32/46

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Experimental tests of Bell’s inequalities at Institut d’Optique (1980-82): past achievements and future directions.

dev — Fri, 27 Dec 2024 12:19:37 +0000

We will review the motivations and history of the experiments that lead to the Nobel Prize in Physics 2022, attributed to Alain Aspect, John Clauser and Anton Zeilinger. We will then discuss some future perspectives, both on the side of quantum technologies, and on the side of the more philosophical issues that motivated initially these experiments.

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This is an onsite event:Auditorium of the Institute of Physics PAS, Al. Lotników 32/46

IM/DD OKD: Intensity modulation/direct detection optical key distribution

dev — Fri, 27 Dec 2024 12:19:37 +0000

Intensity modulation/direct detection optical key distribution (IM/DD OKD) is a technique to generate a cryptographic key over an optical communication link that is secure against passive eavesdropping. The key security is guaranteed by the shot noise inherent to the photodetection process and can be ensured even when the fraction of the signal captured by an eavesdropper is larger than that received by the legitimate recipient. This talk will review the physical principle of IM/DD OKD, present a proof-of-principle demonstration, and discuss estimates for attainable key rates in space-to-ground communication scenarios.

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This is a hybrid event:
Auditorium of the Institute of Physics PAS, Al. Lotników 32/46

Online: Zoom Link, (Passcode: 134595, Meeting ID: 823 8038 0442)

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