Building quantum space-time with spin foams

Informal Discussion with interested students
Thursday, July 11, 11:00
KOSMA-Room (meeting in foyer)

Talk in Theory Colloquium
Friday, July 12, 16:30
Seminar room ETP

 

Spin foam quantum gravity is a non-perturbative, background independent approach to quantizing gravity. It formulates a path integral as a sum over quantum geometries encoded in group theoretic data as in loop quantum gravity; thus it is frequently seen as a way of defining a covariant dynamics for this theory. In this talk, Sebastian Steinhaus from Jena wants to motivate quantum gravity as a manifestly background independent theory and define the gravitational path integral à la spin foams. As a regularisation, he introduces a triangulation and discuss how gravity can be formulated in the discrete, via Regge calculus in a piece-wise flat way. Then he discusses how quantum geometry is encoded in a spin foam and how it connects to Regge calculus in a putative semi-classical limit. He will review outstanding research challenges, in particular for the Lorentzian theory, and discuss concretely the construction of a cosmological model coupled to a scalar field.

Student council shows solidarity with striking Nature workers

Natur workers on strikeNature, one of the most prestigious journals, thrives on letting university employees around the world work for it free of charge. As part of the conversion of the publication system to open access, which we very much welcome, there is an attempt to rip off the universities even more.

At the same time, Nature does not consider it necessary to pay its own employees appropriately. After months of negotiations, they are now on strike. We show solidarity with the colleagues at Nature:

„We, as a physics student council, stand in solidarity with the workers! It can only be in anyone’s interest that publicly funded research is openly accessible. Due to an overly competitive scientific system, many people rely on publishing in prestigious journals, such as Nature, to pursue their careers or apply for grants. In this position of power, nature openly abuses by charging enormously high amounts of money for publishing open access. Many institutions struggle to afford it or are even ruled out directly. Nevertheless, these large profit margins are by no means represented in the workers‘ salaries! We fully support the demands of the strike.“

Und was macht die Fachschaft eigentlich sonst so?

Im SchrankEinige unserer Aktivitäten seht ihr hier auf der Webseite und natürlich auf Insta, noch mehr einfach im Foyer.

Aber vieles läuft auch auf unseren Sitzungen, in Kommissionen usw. Einmal im Semester fahren wir zudem auf ZaPF, um uns mit anderen Physikfachschaften auszutauschen, gemeinsame Initiativen zu starten usw. Dafür schreiben wir auch immer einen Bericht und wir dachten uns: Wir teilen den auch einfach mal hier.

Interessiert einige andere hier sicher auch und ist ja vielleicht auch ne Anregung, mal zu unseren Treffen vorbei zu kommen und sich selbst einzumischen.

GPK: Unconventional magnetism in spintronics: the emergence of altermagnetism and beyond


Tuesday, 4th of June, 16.00
(16.00 Coffee & Cake in the foyer, 16.30 talk & discussion)
Lecture Hall III

Antiferromagnetic spintronics has been a very active research area of condensed matter in recent years. Magnetic order was then also discovered in momentum space, which in turn led to the discovery of completely new magnetic phases beyound ferromegnetism and anti-ferromegnetism: Atermagnets.

Jairo Sinova from Univerity Mainz will cover in his talk the basic introductory view to altermagnetism and its consequences to spintronics as well as new emerging exchange driven phenomena akin to spin-orbit coupling effects, such as p-wave magnetism, emerging from the basic concepts that gave rise to the discovery of altermagnetism.

Full announcement