OXFORD PLASMA THEORY GROUP

PLASMA SEMINARS AND GROUP MEETINGS

The style of the seminars will be informal/chaotic/interactive, following the established tradition. The format of the presentations can be a tutorial on a topic of interest, a report on just completed/ongoing/just starting/potentially interesting research projects, a literature review, a lecture by a passing visitor or anything else worthwhile that anyone cares to suggest. The speakers will be interrupted freely and asked to defend themselves. For background reading, only the most relevant or the most recent references are posted; please follow the paper trail from there. The schedule is subject to change on short notice, but what you see posted here is always up to date; the seminars are also announced via the department's seminar server (group meetings are not). Please email Alex Schekochihin if you would like to receive email updates on these seminars. "Plasma group meetings (or journal clubs)" will discuss current affairs (ongoing projects, new litearture etc.) as well as feature some presentations that are even more informal than seminars. They are open to all members of the Oxford Plasma Theory Group. While some expected contributions are pre-announced, everything is TBC and people wishing their work to be discussed can volunteer contributions without prior notice. Unlike for the seminars, there will not be full-spam-list email reminders of the group meetings. The seminars and group meetings are organised by Michael Barnes and Alex Schekochihin, please contact them with any queries or if you wish to present something.

Past seminar database: Autumn 2007; Winter-Spring 2008; Summer 2008; Autumn 2008; HT 2009; TT 2009; Summer 2009; MT 2009; HT 2009; TT 2010; Summer 2010; MT 2010; HT 2011; TT 2011; Summer 2011; MT 2011; HT 2012; TT 2012; Summer 2012; MT 2012; HT 2013; TT & Summer 2013; MT 2013; HT 2014; TT & Summer 2014; MT 2014; HT 2015; TT & Summer 2015; MT 2015; HT 2016; TT & Summer 2016; Autumn/MT 2016; HT 2017; TT & Summer 2017; Autumn/MT 2017; HT 2018; TT & Summer 2018; MT 2018; HT 2019; TT & Summer 2019; MT 2019; HT 2020; TT & Summer 2020; MT 2020; HT 2021; TT & Summer 2021; Autumn/MT 2021; HT 2021; TT & Summer 2022; Autumn/MT 2022; HT 2023; TT & Summer 2023; Autumn/MT 2023; HT 2024; TT & Summer 2024; Autumn/MT 2024; HT 2025;

Trinity Term & Summer of 2025

The seminars/group meetings will be on Tuesday at 14:00 in the Simpkins Lee Room, Beecroft Building, except where indicated otherwise below, in red.
It will be possible to join these meetings (when they are held in SL Room) on ZOOM --- details available from Alex on request.
Those who join these meetings on ZOOM are asked keep their video cameras on.
The ZOOM system in Simpkins Lee Room does not display a list of participants whose cameras are off. It is not germane to these informal meetings to have invisible listeners of whom those present in the room are unaware, so if you are unable or unwilling to turn on your camera, you cannot join the meeting. 
Here is a list of all Physics seminars.

If you know exactly what you are going to do, what is the point of doing it? Pablo Picasso He goeth furthest who knows not whither he is going. Oliver Cromwell Every line in your calculations ends with "=0". You are not making much progress! Kate Hammett We don't do the calculation because we don't know the answer, we do it because we have a conscience. Bryan Taylor Let's change the resolution on the Unknown. Gabe Plunk Working together takes more than one person. Bill Dorland We can't do ultraviolence to that square bracket. Ian Abel Field lines are forever. Bryan Taylor This is not really an ill-posed problem, this is not a problem at all. Paul Dellar I am just doing mathematics at the moment, but it is mathematics that has some point. Bryan Taylor The equivalent of God in MAST is MHD, which is global and all-powerful. Anthony Field We have crossed all the i's and dotted all the t's. Job's a good'un. Ian Abel Let us not jump in front of the bandwagon! Alex Schekochihin It's not the triviality, it's the emptiness of it that bothers me. Bryan Taylor Never take 0 for an answer. Alex Schekochihin This is a very inefficient way of achieving nothing. Francois Rincon For the sake of fairness, let me mention that some people have objections to this, none of which are particularly valid. Chris Chen This is more or less right. Perhaps less. Alfred Mallet Too simple? At the end of my talk, you will beg for simplicity! Andrey Beresnyak What is the point? The point is not the point! Anonymous This is why I am presenting this here and nowhere else: nothing is solved! Ian Abel Previous studies of this problem have been either unsatisfactory or limited in scope.---What  is the difference between these?---This means either wrong or irrelevant. Anatoly Spitkovsky, Michael Medvedev & Steve Cowley (in conversation) I don't give a damn about astrophysics, explain to me what is going on. Anatoly Spitkovsky Have you subtracted the baby with the bathwater? Steve Balbus This is not rigour, unless you mean rigor mortis. Ian Abel I wouldn't say these are theoretical arguments... Let's just call them arguments. Francois Rincon This qualitative explanation is not of sufficient quality. Eugene Churazov If you mean it seriously, this is actually a very good question. Minhyong Kim This paper is a tour de farce. Ian Abel What is modelling? You run a simulation, you compare. If it coincides, great! If it doesn't coincide, fuck! Felix Parra

It is better to be vaguely right than exactly wrong. Carveth Read (usually attributed to Maynard Keynes) I have seen papers where the student wasn't the problem. Michael Hardman There has been a lot of fascinating work on this subject, most of it kind of boring. Philipp Kempski So now you want us to drop everything we are doing and start worrying about what the big questions are?! Ian Abel Oh dear, I thought I had some conclusions. Nuno Loureiro I've got my little fingers inside this plasma. Steve Cowley Words will play a big role in this talk. Dmitri Uzdensky Everything that can be done should be done---and that's the astrophysical attitude. Michael Medvedev What I will talk about is not low-hanging fruit. A lot of people have looked at this. There is no fruit here at all.---What about sour grapes? Michael Medvedev & Nuno Loureiro In order to have a disappointment, you first have to have an appointment. Alex Schekochihin In our experiment, we observed strong absence of magnetic energy. Archie Bott Much as I somewhat hate this approach... Peter Davidson Your infinity is my zero. Mantas Abazorius If I had known the outcome of this calculation, I would never have done it. Michael Hardman Now that everyone knows this is the new Pandora's box, they are all going to jump into it. Francois Rincon We must think outside the axisymmetric box. Georgia Acton This is not real, it's a Platonic absolute.---The real thing is more Platonic and more absolute. Alex Schekochihin & Anthony Field All I've done here is sacrificed equality in favour of inequality. Per Helander Generally, it depends. Steve Majeski This numerical scheme works fine, but it is physically disgusting. Bruno Despres This research is not only not finished, it has not really been started. Anatoly Spitkovsky This is what really matters... given that "really matters" is a strong word in this context. Robbie Ewart This was discovered accidentally, but it was an informed accident. Plamen Ivanov Infinity is a long way away. Rafael Bailo To solve the kinetic equation on a mesh, you really need to know what you are doing. That's why, historically, people haven't. Rafael Bailo Just shout if you want to chat. Robbie Ewart They ran this simulation for a long time but not forever. Patrick Reichherzer No i's were dotted or t's crossed in the production of this paper. Anonymous

[these quotes are mostly from these seminars and the Vienna meetings]

Wk	Date	Time & place	Speaker & Topic	Background reading	Visitors in town
0	Tue 22 Apr	14:00 SL Room & ZOOM (ask Alex for link)	Plasma Group Meeting (organised by ALEX) 1) Megan Evans --- A minimal model of Floquet modes in a tokamak with flow and magnetic shear 2) Lucas McConnell --- Exposing the importance of kinetic effects in the edge	1) JPP 88, 905880504 (2022) JPP 86, 855860502 (2020)
	Plamen Ivanov returns to Oxford to join the research staff at UKAEA; he will be a permanent visitor at Oxford
I	Tue 29 Apr	14:00 SL Room & ZOOM (ask Alex for link)	Plasma Group Meeting (organised by ALEX) Plamen Ivanov (UKAEA) --- How I spent my time in Lausanne: Turbulence and runaway electrons	PFB 4, 176 (1992) PoP 16, 102308 (2009) NF 60, 126050 (2020) NF 64, 106027 (2024)
II	Mon 5 May	15:00 SL Room & ZOOM (ask Alex for link)	Plasma Group Meeting (organised by ALEX) Jon Hillesheim (CFS) --- ARC Design Update		Jon Hillesheim (CFS) Arnas Volcokas (EPFL)
	Tue 6 May	14:00 SL Room & ZOOM (ask Alex for link)	Plasma Seminar (organised by PLAMEN) Arnas Volcokas (EPFL) --- Gyrokinetic investigation of plasma turbulence self-organization at low magnetic shear in tokamaks	NF 63, 014003 (2023) arXiv:2502.04459 arXiv:2503.08793
III	Tue 13 May	14:00 SL Room & ZOOM (ask Alex for link)	Plasma Seminar (organised by DMITRI) John Mehlhaff (Grenoble) --- TBA		John Mehlhaff (Grenoble)
IV	Tue 20 May	14:00 SL Room & ZOOM (ask Alex for link)	Plasma Seminar (organised by DMITRI) Fabio Bacchini (KU Leuven) --- TBA		Fabio Bacchini (KU Leuven)
V	Mon 26 May	15:00 SL Room & ZOOM (ask Alex for link)	Plasma Seminar/Lamb Lectures (organised by ALEX & SHIVAJI SONDHI) Steve Cowley (Princeton) --- Explosive instability and metastability Magnetised plasmas---whether in nature or in the laboratory---often undergo sudden, dramatic eruptions that release large amounts of energy and disrupt confinement. Why some plasmas erupt while others remain limited by turbulence is still not fully understood. In this talk, I will examine the instability mechanisms that drive eruptive behavior and argue that many plasmas are metastable, stable to small perturbations but unstable to large perturbations. When triggered, this metastable state can lead to explosive events. I will highlight how this phenomenon manifests in both edge localized modes (ELMs) in fusion devices and in solar flares. Following such eruptions, the plasma must settle into a new equilibrium. I will present key examples where these relaxed equilibrium states can be calculated accurately.	JPP 91, E35 (2025) Proc Roy Soc A 471, 20140913 (2015) Phys Rep 283, 185 (1997)	Steve Cowley (Princeton)
	Tue 27 May	14:00 SL Room & ZOOM (ask Alex for link)	Plasma Seminar/Lamb Lectures (organised by ALEX & SHIVAJI SONDHI) Steve Cowley (Princeton) --- Topology change in 3D magnetic fields The topology of magnetic fields plays a central role in determining plasma behaviour. Topological changes typically occur through magnetic reconnection, which has been extensively studied in two dimensions. In three dimensions, however, reconnection is not well-defined---and the very notion of topological change becomes ambiguous. In this talk, I will explore these challenges and propose a useful framework for understanding reconnection in 3D magnetic fields. In this picture, the reconnection timescale is governed by the rate at which neighboring field lines diverge as one follows the field. I will derive the reconnection timescales for both linear and exponential field-line separation. Interestingly, the analysis reveals that faster separation leads to slower reconnection---contradicting some recent claims in the literature.	arXiv:2412.01736
	Thu 29 May	17:00 M. Wood LT	Willis Lamb Lecture (organised by SHIVAJI SONDHI) Steve Cowley (Princeton) --- Fusion energy: why, how and when In a remarkable public lecture in 1920, Arthur Eddington speculated that fusion might become the ultimate long-term energy source. More than a century later, we are approaching the milestone of generating electricity from fusion for the first time. The US National Academies have urged that "the Department of Energy and the private sector should produce net electricity in a fusion plant in the United States in the 2035-40 timeframe." This is an ambitious goal---but recent breakthroughs in both magnetic and inertial fusion, combined with a surge of private-sector investment, suggest that success may be within reach. In this talk, I will outline the progress made and the challenges that remain.
VI	Mon 2 June	15:00 SL Room & ZOOM (ask Alex for link)	Plasma Seminar (organised by ALEX) Jono Squire (Otago) --- TBA/TBC		Jono Squire (Otago) Daniel Verscharen (UCL/MSSL)
	Tue 3 June	14:00 SL Room & ZOOM (ask Alex for link)	Plasma Seminar (organised by MICHAEL NASTAC) Daniel Verscharen (UCL/MSSL) --- TBA
VII	Tue 10 June	14:00 SL Room & ZOOM (ask Alex for link)	Plasma Group Meeting (organised by DMITRI) TBA
VIII	Mon 16 June	TBA Culham	Special Seminar at UKAEA (organised by FULVIO MILITELLO) David Hosking (Cambridge) --- Catastrophic eruptions in magnetically confined plasmas		Tunde Fulop (Chalmers) David Hosking (Cambridge)
	Tue 17 June	14:00 SL Room & ZOOM (ask Alex for link)	Plasma Group Meeting (organised by ALEX) Barry Ginat --- Cosmological tensions [Cosmology for dummies: update on waning dark energy, clumping dark matter etc.]	A&A 641, A6 (2020) arXiv:2503.14454 arXiv:2503.14738
9	Tue 24 June	14:00 SL Room & ZOOM (ask Alex for link)	Plasma Group Meeting (organised by ALEX) Valerian Hall-Chen (A*STAR, Singapore) --- TBA		Valerian Hall-Chen (A*STAR, Singapore)
	Tue 1 July	14:00 SL Room & ZOOM (ask Alex for link)	Plasma Group Meeting (organised by ALEX) TBA		Valerian Hall-Chen (A*STAR, Singapore)
	Tue 8 July	14:00 SL Room & ZOOM (ask Alex for link)	Plasma Group Meeting (organised by ALEX) TBA		Valerian Hall-Chen (A*STAR, Singapore)
	Tue 15 July	14:00 SL Room & ZOOM (ask Alex for link)	Plasma Group Meeting (organised by ALEX) TBA		Robbie Ewart (Princeton) Luis Silva (IST Lisbon)
	Tue 22 July	14:00 SL Room & ZOOM (ask Alex for link)	Plasma Group Meeting (organised by ???) TBA		Luis Silva (IST Lisbon)
	Tue 29 July	14:00 SL Room & ZOOM (ask Alex for link)	Plasma Group Meeting (organised by ???) TBA
	Tue 5 Aug	14:00 SL Room & ZOOM (ask Alex for link)	Plasma Group Meeting (organised by ALEX) TBA

Michaelmas Term of 2025