سخنران:

12 بهمن 1401
11:00 تا 12:00

ارتقاء سیستم اتصال
RPC
در فاز دوم ارتقاء آشکارساز
CMS:
مروری بر سیستم و اعتبارسنجی

سخنران: امیر رضایی

12 بهمن 1401
14:00 تا 15:00

چکیده:

Inside living cells many essential processes involve deformation of charged helical molecules and interaction between them. Actin filaments and DNA molecules with linear charge distribution -1e/0.27nm and -2e/0.34nm respectively, are important examples of charged helical molecules. On the other hand, the existence of salt concentration inside the cell environment emphasizes on the crucial role of the electrostatic interactions in biological systems. Here we consider an impermeable dielectric molecule in the solvent with a different dielectric constant. The electrostatic free energy in the problem is studied in the Debye-Huckel regime using the analytical Green function method. Using this electrostatic free energy, we study the electrostatic contribution to the twist rigidity of a double stranded helical molecule such as DNA and actin filaments. The dependence of the electrostatic twist rigidity of the molecule to the dielectric inhomogeneity, structural parameters and the salt concentration is studied. It is shown that, depending on the parameters, the electrostatic twist rigidity could be positive or negative.


برای شرکت در این وبینار وارد لینک زیر شده و به صورت میهمان لاگین کنید


https://www.skyroom.online/ch/schoolofnanoscience/weeklyseminars

سخنران: M.M. Sheikh-Jabbari, School of Physics

11 بهمن 1401
14:00 تا 15:00

Date and time

Tuesday, 31th of January 2023 (11th of Bahman, 1401), 2:00 pm (Tehran zone)

Link

https://www.skyroom.online/ch/schoolofphysics/highenergyseminar



Abstract

We construct microstates of 3d black holes in the Hilbert space of tensionless null strings with non-zero winding along the bifurcation horizon. Counting these string states we recover the Bekenstein-Hawking entropy and its semiclassical logarithmic corrections.

سخنران: دکتر عادله مخلص گرامی - پژوهشگاه دانشهای بنیادی

10 بهمن 1401
11:00 تا 12:00

بررسی ماهیت رانش یون های فلزی در دستگاه های ممریستور از طریق کاشت یونهای رادیواکتیو

سخنران: دکتر بهزاد بقراطی (پژوهشگاه دانشهای بنیادی، دانشگاه دامغان)

5 بهمن 1401
11:00 تا 12:00

ارتقاء سیستم اتصال
RPC
در فاز دوم ارتقاء آشکارساز
:CMS
مروری بر سیستم و اعتبارسنجی

سخنران: واسلی گلیشف, IITP Moscow, Russia

5 بهمن 1401
16:30 تا 18:00

I will give a survey of some problems and recent results concerning the link between the monodromies of structure connections on certain Frobenius manifolds with the numerology of the derived categories of Fano varieties.





Zoom link:


https://zoom.us/j/92708332316?pwd=MGlBRWhTUy9wSzg5VGppTUNQVXN6dz09


Meeting ID: 927 0833 2316


Passcode: 692489








Subscribing the Mathematics Colloquium mailing list:


https://groups.google.com/g/ipm-math-colloquium

سخنران: س. فخری، دانشگاه خواجه نصیرالدین طوسی

4 بهمن 1401
14:00 تا 15:00

Date and time
Tuesday- 24th of January 2023 (4th of Bahman, 1401)- 2:00 pm (Tehran zone)

Link
https://www.skyroom.online/ch/schoolofphysics/highenergyseminar


Abstract
Cosmic voids are known as underdense substructures of the cosmic web that cover a large volume of the Universe. It is known that cosmic voids contain a small number of dark matter halos. Regarding this, the existence of primordial black holes (PBHs) in these secluded regions of the Universe is not unlikely. In this talk, I intend to speak about our recent analysis on the merger rate of PBHsin cosmic voids and their contribution to gravitational wave events resulting from black hole mergers recorded by the Advanced Laser Interferometer Gravitational-Wave Observatory (aLIGO)-Advanced Virgo (aVirgo) detectors.

سخنران: دکتر سیده صدیقه هاشمی - پژوهشگاه دانشهای بنیادی

3 بهمن 1401
11:00 تا 12:00

طراحی تفنگ فوتوکاتد فرکانس رادیویی برای پروژه چشمه نور

سخنران: خانم یاسمن حسینی (پژوهشگاه دانشهای بنیادی، پژوهشکده ذرات و شتابگرها)

28 دی 1401
11:00 تا 12:00

حدهای یکانی و جستجو برای فوتون تاریک در برخورددهنده ها

سخنران: محمدرضا شعبان نیا

28 دی 1401
14:00 تا 15:00

چکیده:

Separation of magnetic or magnetically labeled biological or synthetic particles in micro-fluidic setups has been recently achieved by subjecting them to an external magnetic field to produce controlled alterations in the flow-driven motion of target particles based on their size, shape and magnetic properties. We investigate Brownian noise effects on magnetic focusing of prolate and oblate spheroids carrying permanent magnetic dipoles in channel (Poiseuille) flow subject to a uniform magnetic field. The focusing is effected by the low-Reynolds-number wall-induced hydrodynamic lift which can be tuned via tilt angle of the field relative to the flow direction.

This mechanism is incorporated in a steady-state Smoluchowski equation that we solve numerically to analyze the noise effects through the joint position-orientation probability distribution function of spheroids within the channel. We complement this approach by analyzing stability of deterministic fixed points and a reduced onedimensional probabilistic theory which we introduce to semi-quantitatively explain noise-induced behavior of pinned spheroids under strong fields. The results reveal remarkable and even counterintuitive noise-induced phenomena that include fieldinduced defocusing upon strengthening the field. We map out focusing ‘phase’ diagrams based on the field strength and tilt angle to illustrate different regimes of behavior including centered focusing and defocusing in transverse/longitudinal fields and off-centered focusing in tilted fields. The latter encompasses two subregimes of optimal and shouldered focusing where spheroidal density profiles across the channel width display either an isolated off-centered peak or a skewed peak with a pronounced shoulder stretching toward the channel center. We also elucidate the implications of our results for efficient shape-based sorting of magnetic spheroids.


برای شرکت در این وبینار وارد لینک زیر شده و به صورت میهمان لاگین کنید


https://www.skyroom.online/ch/schoolofnanoscience/weeklyseminars

سخنران: M.H. Vahidinia, IASBS

27 دی 1401
14:00 تا 15:00

Date and time
Tuesday, 17th of January 2023 (27th of Dey, 1401), 2:00 pm (Tehran zone)


Link
https://us02web.zoom.us/j/89461255809?pwd=d3RhVjNlaVl5aURRMFVHYnlVajdzUT09



Meeting ID: 894 6125 5809
Passcode: 873704



Abstract

We consider the standard Maxwell's theory in 1+3 dimensions in the presence of a timelike boundary. In this context, we show that (generalized) Ampere-Maxwell's law appears as a Noether charge associated with the Maxwell U(1) gauge symmetry which satisfies a spatial conservation equation. Furthermore, we also introduce the notion of spatial memory field and its corresponding memory effect. Finally, similar to the temporal case through the lens of Strominger's triangle proposal, we show how spatial memory and conservation are related.

سخنران: دکتر سید محمدعلی طباطبائی مهر- پژوهشگاه دانشهای بنیادی

26 دی 1401
11:00 تا 12:00

شواهد تغییر شکل های چهار و هشت قطبی در برخورد فوق نسبیتی


Zr96+Zr96 and Ru96+Ru96

سخنران: M.J.Kazemi, Sharif University of Technology

20 دی 1401
14:00 تا 15:00

Date and time

Tuesday, 10th of January 2023 (20th of Dey, 1401), 2:00 pm (Tehran zone)



Link
https://us02web.zoom.us/j/89461255809?pwd=d3RhVjNlaVl5aURRMFVHYnlVajdzUT09



Meeting ID: 894 6125 5809
Passcode: 873704



Abstract

Double-slit experiment has always been one of the central experiments in quantum mechanics. Yet, if there is an experiment more mysterious, it is a double-double-slit experiment with entangled particle pairs. In this experiment, the two most important properties of quantum theory, i.e. superposition and entanglement, combine and lead to a non-local interference pattern. The full analysis of this experiment can be even more complex because of the third quantum effect, i.e. the collapse of the wave function when the first particle is detected in the middle of the experiment at random times. This, in principle, can change the detection statistics of the remaining particle. The analysis however is not completely straightforward in standard formalism. One of the reasons is that in the orthodox quantum mechanics we do not have a clear and agreed prediction of detection times distribution. This problem is actually very old, but it is still open. The mathematical origin of this problem is that the time is a parameter in the standard formalism, not a self-adjoint operator, hence, there is no unique and unambiguous way to compute the temporal probability distribution of detection events. Therefore, it is even not clear how one can determine the state of the system at a given time from initial two particle state; because the state and its equation of motion change at an undetermined time. In this talk, we investigate this experiment via Bohmian mechanics which can circumvent this problem and leads to a clear prediction in this situation.

سخنران: دکتر افسانه کیانفر - پژوهشگاه دانشهای بنیادی

19 دی 1401
11:00 تا 12:00

حد جفت‌شدگی ضعیف مدل شبکه
U(1)
در پایه فوریه