Monday, July 3, 2023

TWAS’s 40th Anniversary

The World Academy of Sciences for the advancement of science in developing countries (TWAS) is an organization that has been at the forefront of promoting scientific excellence in the developing world.

Founded in 1983, TWAS has been a driving force in supporting scientists from diverse backgrounds and fostering global collaborations. This year marks the 40th anniversary of TWAS, and its President, Quarraisha Abdool Karim, has launched the celebrations to honor this momentous occasion.

On 25 May 2023, as the Executive Director of TWAS, I had the pleasure to open the anniversary event – a public lecture by TWAS President. I was joined onstage Stefano Fantoni, president of the Trieste International Foundation for the Progress and Freedom of Sciences (FIT); and Minister Plenipotentiary Giuseppe Pastorelli, director for integrated promotion and innovation at the Directorate General for Country Promotion of the ministry of Foreign Affairs and International Cooperation of Italy, a key supporter of TWAS.

From bridging the scientific divide to promoting sustainable development goals and empowering young scientists, TWAS has demonstrated its unwavering commitment to promoting scientific excellence worldwide. As we celebrate this milestone, let us remember that together we can forge a brighter and more equitable future through the power of scientific knowledge.

On the TWAS website https://twas.org/article/twas-president-launches-celebrations-academys-40th-anniversary you can read an article about the event.

With TWAS President Abdool Karim

 

Integral Quantization for the Discrete Cylinder

by  1,* and 2

1
CNRS, Astroparticule et Cosmologie, Université Paris Cité, 75013 Paris, France
2

Abstract: Covariant integral quantizations are based on the resolution of the identity by continuous or discrete families of normalized positive operator valued measures (POVM), which have appealing probabilistic content and which transform in a covariant way. One of their advantages is their ability to circumvent problems due to the presence of singularities in the classical models. In this paper, we implement covariant integral quantizations for systems whose phase space is Z × S^1 , i.e., for systems moving on the circle. The symmetry group of this phase space is the discrete & compact version of the Weyl–Heisenberg group, namely the central extension of the abelian group Z × SO(2). In this regard, the phase space is viewed as the right coset of the group with its center. The non-trivial unitary irreducible representation of this group, as acting on L ^2 (S^1), is square integrable on the phase space. We show how to derive corresponding covariant integral quantizations from (weight) functions on the phase space and resulting resolution of the identity. As particular cases of the latter we recover quantizations with de Bièvre-del Olmo–Gonzales and Kowalski–Rembielevski–Papaloucas coherent states on the circle. Another straightforward outcome of our approach is the Mukunda Wigner transform. We also look at the specific cases of coherent states built from shifted gaussians, Von Mises, Poisson, and Fejér kernels. Applications to stellar representations are in progress.

Gazeau, J.-P.; Murenzi, R. Integral Quantization for the Discrete Cylinder. Quantum Rep. 2022, 4, 362–379. https://doi.org/10.3390/ quantum4040026.
https://www.mdpi.com/2624-960X/4/4/26.