FYI, ein CAL Vortrag -------- Weitergeleitete Nachricht -------- Betreff: Colloquium by Nathan Lundblad at LUH 22.May 2025; 16- 17:30 pm Datum: Mon, 12 May 2025 11:49:56 +0200 Von: Anke Schmidt <anke.schmidt@DQ-MAT.UNI-HANNOVER.DE> Antwort an: Anke Schmidt <anke.schmidt@DQ-MAT.UNI-HANNOVER.DE> An: MEMBERS-DQMAT@LISTSERV.UNI-HANNOVER.DE Dear DQ-mat members and interested scientists, We are are pleased to announce the next Colloquium which will take place on *_Thursday, 22.May 2025_*_- *16:00 - 17:30 pm* __LUH__, Building 1101, Room D326, Welfengarten 1, 30167 Hannover _ Colloquiumby *Nathan Lundblad - *Bates College, Maine, United States of America Title: Ultracold Bubbles in Space: Atomic Physics Aboard the International Space Station Abstract: Exploring the effects of geometry, topology, dimensionality, and interactions on ultracold atomic ensembles has been a continually fruitful line of inquiry in the decades since the first observation of Bose-Einstein condensation (BEC). One previously unexplored configuration for ultracold ensembles is that of a bubble or shell, where trapped atoms are confined in the vicinity of a spherical or ellipsoidal surface. Such a quantum system could offer new collective modes, topologically-sensitive behavior of quantized vortices, self-interference and shell collapse, as well as the exploration of trapped ultracold systems with mm-scale spatial extent. While techniques for the generation of bubble-shaped traps have been known since 2001, terrestrial gravity has thus far limited the convenient observation of ultracold bubbles. With the construction of the NASA Cold Atom Lab (CAL) facility and its subsequent delivery in 2018 to the International Space Station (ISS) and commissioning as an orbital BEC user facility, experimental atomic physics schemes that require a sustained microgravity environment are now possible.  I will review CAL observations of trapped bubbles of ultracold atoms, including a variety of bubble-trap configurations that are possible with this apparatus. I will also discuss the thermodynamics of ultracold bubbles and review open questions being explored in the ongoing second science run of CAL aboard ISS, which feature improved bubble aspect ratios and filling as well as improved imaging; I will also review upcoming changes to the CAL facility, recent progress made with shell structures in terrestrial laboratories, and the bubble-making potential of the Einstein Elevator. Access data for the transfer: Zoom Access:**https://us04web.zoom.us/j/932734874 This talk is part of the "Virtual Seminar on Precision Physics and Fundamental Symmetries" series and of the SFB DQ-mat colloquium series:https://indico.cern.ch/category/12183/ Best regard, Anke Schmidt -- Leibniz Universität Hannover DQ-Mat-Office, Room 308 Callinstraße 36 30167 Hannover Tel: +49 511 76214887 Fax: +49 511 76217243 Email:anke.schmidt@dq-mat.uni-hannover.de https://www.dq-mat.uni-hannover.de/ https://www.quest-lfs.uni-hannover.de/ https://www.hitec.uni-hannover.de/ https://www.quantumfrontiers.uni-hannover.de/ https://www.qvls.de