Friday 13 December 2024 |
Events for day: Wednesday 27 November 2024 |
11:00 - 12:00 Wednesday Weekly Seminar - Hybrid Format Design of a high-current, low-emittance electrostatic electron gun for the Iranian Light Source Facility's electron preinjector, and investigation of its electron beam dynamics School PARTICLES AND ACCELERATORS Abstract: The pre-injector of the Iranian Light Source Facility consists of a radiofrequency electron gun, longitudinal and transverse focusing magnets, linear accelerators, and several other ancillary parts. Since the emittance of the ILSF electron beam at the end of the linear accelerators reaches about 8 mm-mrad, we intend to achieve a lower emittance by designing an electrostatic electron gun. Also, electrostatic electron gun pre-injectors do not require alpha magnets and instead have several beam bunchers, contributing to this type's lower emittance. Reducing the emittance in the electron pre-injector does n ... 14:00 - 15:00 Combinatorics and Computing Weekly Seminar Introduction to Blockchain Basics, the Scaling Challenge, and the Proof-of-Stake Scheme School MATHEMATICS Blockchains provide the opportunity for the first large permission-less trust-less distributed network. In this talk, we review the basic working principles of blockchains, which provide the infrastructure of cryptocurrencies, like Bitcoin. Although, the security features of such a system are promising, other performance metrics such as throughput and delay do not scale with the network size. We will discuss the basic scaling limitations and the proposed solutions. Finally, we review the Proof-of-Stake (PoS) method which is the main alternative for the traditional Proof-of-Work (PoW) scheme, and discuss its main benefits and challenges. ... 14:00 - 15:00 Weekly Seminar Designing self-assembling polymeric coatings by dissipative particle dynamics simulations School NANO SCIENCES Interfacial coatings by, e.g., polymers, are often used to modify surface interactions of materials, or to protect the underlying substrate. Self-assembling polymer coatings find use e.g., as protective layers in biomedical applications, as anti-corrosion coats protecting metallic surfaces, but also as preservative layers conserving stone materials in architectural monuments. Advanced uses require control of the assembling structure and coating spreading. Computational modelling provides an effective means to reveal guidelines for these, e.g., in terms of polymer component choices, their miscibilities, or degree of polymerization. ... 15:30 - 17:00 Geometry and Topology Weekly Seminar Generalizations of Rasmussen?s invariant School MATHEMATICS Over the last 20 years, the Rasmussen invariant of knots in S^3 has had a number of interesting applications to questions about surfaces in B^4. In this talk I will survey some recent extensions of the invariant to knots in other three-manifolds: in connected sums of S^1 x S^2 (joint work with Marengon, Sarkar, and Willis), in RP^3 (joint work with Willis, and also separate work of Chen), and in a general setting (work by Morrison, Walker and Wedrich; and independently by Ren-Willis). I will describe how these invariants give bounds on the genus of smooth surfaces in 4-manifolds, and can even detect exotic 4-manifolds with boundary. < ... 17:30 - 19:00 Algebraic Geometry Biweekly Webinar On Smooth Rational Complete Intersections School MATHEMATICS The known results about the rationality vs irrationality of smooth Fano complete intersections $X^nsubsetmathbb P^{n+c}$ of dimension $n=3,4,5$ and fixed type $(d_1,ldots, d_c)$ suggest an uniform approach to treat several open cases: index one; index two; quartic fourfolds and fivefolds; etc. From one hand one would like to decide the rationality/irrationality of every element in the numerous cases where the stable irrationality of the very general element is known (e.g. quartic fourfolds and fivefolds, quintic fivefolds, etc); from the other hand one hopes to put some further light on several longstanding conjectures (e.g. the ... |