Departementsdag

28 maart 2019

Programma

De jaarlijkse natuurkunde departmentsdag is een leuke informele gelegenheid waarop iedereen die betrokken is bij het departement natuurkunde samenkomt. Er zijn lezingen van hoogleraren, acts van de studenten en een postersessie door de PhD studenten. Iedereen is van harte uitgenodigd om deze dag bij te wonen, aanmelden is niet nodig. Daarnaast zullen we de dag afsluiten met een gratis borrel en buffet. Hopelijk zien we je daar!

Tijd KBG Cosmos Minnaert Hal
13:15 Stefan Vandoren: Grand Challenges in Physics
14:15 Marjolein Dijkstra: Inverse Design and Machine Learning for Soft Materials: Crystals, Quasi Crystals, and Liquid Crystals Start science fair
15:00 Student act
15:45 Erik van Sebille: Lost at sea: how ocean currents transport My Little Ponies and other plastic pollution
16:30 Auke-Pieter Colijn: Experiments under a mountain End science fair
17:15 Poster session and drinks
18:15 Drinks and dinner

Abstracts

Stefan Vandoren: Grand Challenges in Physics

We look at some of the grand challenges in physics, mostly from a personal point of view. I will then attempt to describe how we attack some of them in Utrecht, both from the viewpoint of reductionism and emergence.

Marjolein Dijkstra: Inverse Design and Machine Learning for Soft Materials: Crystals, Quasi Crystals, and Liquid Crystals

In 1960, Feynman challenged us to think "from the bottom up" and to create new functional materials by directing and manipulating the arrangements of individual atoms ourselves. With recent advances in the synthesis of colloidal nanoparticles and the bottom-up fabrication of nanostructured materials using colloidal self-assembly, we are tantalizingly close to realizing this dream. In this talk, I will show using theory and simulations how one can structure matter over multiple length scales using self-assembly. The prediction and design of these structures remains an important challenge for nanomaterials science. I will present a method to predict which structures are stable assuming the shape and interactions between the constituent particles are known, and I will show that particle shape alone can already give rise to a wide variety of structures which can be classified using machine learning techniques. Subsequently, I will show how one can reverse-engineer the particle shape to stabilize highly exotic liquid crystal phases.

Erik van Sebille: Lost at sea: how ocean currents transport My Little Ponies and other plastic pollution

On New Year&aposs Day 2019, the MSC Zoe - one of the largest container ships in the world - lost more than 30 containers just north of the Wadden Islands. While a potential disaster for the fragile local ecosystems, the cargo in these containers also provides a unique natural experiment to investigate how ocean currents disperse plastic pollution. Most of our planet"s surface is ocean, and it"s in constant motion. Currents and waves move plastic pollution and other debris around the globe. But these currents are unpredictable, making it very difficult to accurately predict where plastic ends up. In this talk, I will show how oceanographers at IMAU go about simulating movement of ocean currents, and how they use those simulations to track the debris from the MSC Zoe and the other millions of tons of plastic pollution that enter our oceans every year. See also this NOS article (in Dutch)

Auke-Pieter Colijn: Experiments under a mountain

The detectors of the XENON collaboration are hidden deep inside the Gran Sasso mountain range near l"Aquila (Italy). I will talk about the unsuccessful hunt for dark matter with the XENON1T detector and about the next big thing we are building under our mountain: XENONnT. Once operational we will not just have a detector to hunt for dark matter, but the detector is so big that it will start to become sensitive to other interesting physics, like supernova neutrino"s and rare decays of xenon. I will finish with an outlook of the future of xenon filled dark matter detectors, and some other completely different projects that we could do under our mountain.