Wed 14 Feb 16:30: Statistics Clinic Lent 2024 III
This free event is open only to members of the University of Cambridge (and affiliated institutes). Please be aware that we are unable to offer consultations outside clinic hours.
If you would like to participate, please sign up as we will not be able to offer a consultation otherwise. Please sign up through the following link: https://forms.gle/Qmd2bef3cBHzMUwQ8. Sign-up is possible from Feb 8 midday until Feb 12 midday or until we reach full capacity, whichever is earlier. If you successfully signed up, we will confirm your appointment by Feb 14 midday.
- Speaker: MR5 at the CMS
- Wednesday 14 February 2024, 16:30-18:00
- Venue: MR5.
- Series: Cambridge Statistics Clinic; organiser: Manuel Müller.
Wed 31 Jan 16:30: Statistics Clinic Lent 2024 II
This free event is open only to members of the University of Cambridge (and affiliated institutes). Please be aware that we are unable to offer consultations outside clinic hours.
If you would like to participate, please sign up as we will not be able to offer a consultation otherwise. Please sign up through the following link: https://forms.gle/6rQZ2JSNQ6Ehtc7X9. Sign-up is possible from Jan 25 midday until Jan 29 midday or until we reach full capacity, whichever is earlier. If you successfully signed up, we will confirm your appointment by Jan 31 midday.
- Speaker: MR5 at CMS
- Wednesday 31 January 2024, 16:30-18:00
- Venue: MR5.
- Series: Cambridge Statistics Clinic; organiser: Manuel Müller.
Fri 09 Feb 13:00: Title to be confirmed
Abstract not available
- Speaker: Tereza Jarníková, University of East Anglia
- Friday 09 February 2024, 13:00-14:00
- Venue: BAS Seminar Room 1; zoom.
- Series: British Antarctic Survey - Polar Oceans seminar series; organiser: Dr Birgit Rogalla.
Fri 02 Feb 16:00: Turbulent-laminar patterns
Experiments and numerical simulations have shown that turbulence in transitional wall-bounded shear flows such as plane Couette and Poiseuille flow frequently takes the form of long oblique bands, if the domains are sufficiently large to accommodate them. At their upper Reynolds-number threshold, laminar regions carve out gaps in otherwise uniform turbulence, thereby forming regular oblique turbulent-laminar patterns with a large spatial wavelength. At the lower threshold, isolated turbulent bands sparsely populate otherwise laminar domains and complete laminarization takes place via their disappearance characterized by the 2D directed percolation scenario.
- Speaker: Laurette Tuckerman, ESPCI Paris
- Friday 02 February 2024, 16:00-17:00
- Venue: MR2.
- Series: Fluid Mechanics (DAMTP); organiser: Professor Grae Worster.
Mon 22 Jan 11:45: GKM-Theory for cyclic quiver Grassmannians EMGW02 - Applied and computational algebraic geometry
After recalling some background on Goresky-Kottwitz-MacPherson (GKM) version of the Localization Theorem for equivariant cohomology, and some of the applications of such a result, I will explain how it is possible and why it is desirable to extend such techniques to the quiver Grassmannian setting. This is joint work with Alex Puetz.
EMGW02 - Applied and computational algebraic geometry
- Speaker: Martina Lanini (Università degli Studi di Roma Tor Vergata)
- Monday 22 January 2024, 11:45-12:45
- Venue: Seminar Room 1, Newton Institute.
- Series: Isaac Newton Institute Seminar Series; organiser: nobody.
Wed 17 Jan 16:00: Lighting the Quantum Future
Light has a central role in emerging quantum technologies because of its ability to control matter and its unique capacity for displaying quantum features in ambient condition. Non-error corrected optical quantum machines performing specialised tasks have already demonstrated a quantum advantage over the best algorithms running on conventional computers, and practical applications for such machines are being explored. Meanwhile, designs for error-corrected fault-tolerant quantum computers based on light are reducing the performance requirements for individual components and systems, although the engineering challenges are severe. I will outline some recent progress toward scaling photonic quantum simulation and new modes of harnessing light in quantum computing. See also: Optica Quantum, Vol. 1, Issue 1, pp. 35-40, (2023)
- Speaker: Prof Ian Walmsley FRS, Imperial College London
- Wednesday 17 January 2024, 16:00-17:00
- Venue: Small Lecture Theatre, Cavendish Laboratory, J.J. Thomson Avenue.
- Series: Cavendish Quantum Colloquium; organiser: Dr Nur Unal.
Fri 09 Feb 16:00: Closing in on New Physics with the Flavor, Collider, and Electroweak Triad
Any new physics (NP) lying at the TeV scale must pass stringent flavor as well as collider bounds. Since the top Yukawa gives the largest quantum correction to the Higgs mass, one well-motivated expectation is TeV-scale NP dominantly coupled to the third family. This setup delivers U(2) flavor symmetries that allow one to start explaining flavor at the TeV scale, while simultaneously improving compatibility with the aforementioned bounds.
In all such models that also seek to address the hierarchy problem or the flavor puzzle, there are unavoidably new particles with sizable couplings to the Higgs. Integrating out these heavy particles generates contributions to SMEFT operators that modify EW precision observables, which are precisely measured on the Z- and W-poles. We therefore have a triad of bounds that all models of this type must pass: flavor, direct collider searches, and EW precision tests.
The SMEFT in the U(2)^5 symmetric limit contains only 124 independent operators. This makes an exhaustive phenomenological study tractable, where one can place bounds on all of these operators from each prong of the triad. I will show that while flavor bounds depend on how U(2) is broken, the U(2) symmetric limit is sufficient for EW and collider parts of the triad, which most strongly constrain the flavor conserving parts of the operators. Additionally, important effects come from resummed RGE , in particular from operators with third-family quarks running strongly into Higgs operators constrained on the Z-pole. Finally, I present projections showing how the FCC -ee Z-pole run will indirectly probe a plethora of operators via their unavoidable RG mixing into Higgs operators.
- Speaker: Benjamin Stefanek (King's Coll. London)
- Friday 09 February 2024, 16:00-17:00
- Venue: MR19 (Potter Room, Pavilion B), CMS.
- Series: HEP phenomenology joint Cavendish-DAMTP seminar; organiser: Nico Gubernari.
Wed 21 Feb 14:00: Information-theoretic techniques and context-tree methods for time series
Building on the context-tree weighting (CTW) circle of ideas, we introduce a collection of statistical ideas and algorithmic tools for modelling and performing exact inference with both discrete and real-valued time series. For discrete time series, we describe a novel Bayesian framework based on variable-memory Markov chains, called Bayesian Context Trees (BCT). A general prior structure is introduced, and a collection of methodological and algorithmic tools is developed, allowing for efficient, exact Bayesian inference. The proposed approach is then extended to real-valued time series, where it is employed to develop a general hierarchical Bayesian framework for building mixture models based on context trees. Again, effective computational tools are developed, allowing for efficient, exact Bayesian inference. The proposed methods are found to outperform several state-of-the-art techniques on both simulated and real-world data from a wide range of applications. This is joint work with Ioannis Kontoyiannis.
- Speaker: Ioannis Papageorgiou, University of Cambridge
- Wednesday 21 February 2024, 14:00-15:00
- Venue: MR5, CMS Pavilion A.
- Series: Information Theory Seminar; organiser: Prof. Ramji Venkataramanan.
Fri 23 Feb 16:00: On amplitudes and field redefinitions
All QFT Lagrangians are redundant, in the sense that you can locally and invertibly redefine its fields without changing its amplitudes. Much like gauge redundancy in gauge theory, field redefinitions mix physics between different Feynman graphs, and induce large cancellations between graphs, making amplitudes difficult to calculate.
I will describe a compact functional formulation to describe the effects of field redefinitions and show how it can generate new off-shell recursion relations for amplitudes, based on arXiv:2202.06965 and arXiv:2312.06748. I will speculate how an improved understanding of transformations under field redefinitions could help calculate phenomenologically useful amplitudes more efficiently.
- Speaker: David Sutherland (University of Glasgow)
- Friday 23 February 2024, 16:00-17:00
- Venue: MR19 (Potter Room, Pavilion B), CMS.
- Series: HEP phenomenology joint Cavendish-DAMTP seminar; organiser: Terry Generet.
Fri 02 Feb 16:00: Quantum entanglement of top quarks
The ATLAS Collaboration recently reported the observation of quantum entanglement between top quarks. This constitutes the first observation of entanglement in a pair of quarks, and the observation of entanglement at the highest energy to date. Prompted by these results, I will illustrate recent developments in the field of quantum information theory in collider experiments, as this measurement paves the way to use colliders as a laboratory to study quantum information and other foundational properties of quantum mechanics. Furthermore, other similar measurements such as measuring quantum discord, reconstructing the quantum steering ellipsoid, and even establishing a violation of Bell inequalities, may be achievable at the LHC in the near future. From a high-energy physics perspective, borrowing concepts from quantum information theory inspires new approaches and observables that can be used to search new phenomena that may have escaped detection so far.
- Speaker: Claudio Severi (U. Manchester)
- Friday 02 February 2024, 16:00-17:00
- Venue: MR19 (Potter Room, Pavilion B), CMS.
- Series: HEP phenomenology joint Cavendish-DAMTP seminar; organiser: Nico Gubernari.