What happened at the LISA Cosmology Working Group workshop

The LISA Cosmology Working Group Workshop dinner at Särkänlinna restaurant.

Credit: Anna Kormu

Visiting graduate student Daniel Cutting has written a short summary of what happened at last week’s LISA Cosmology Working Group Workshop in Helsinki. Here is what he has to say:

During the last week, the Helsinki Institute of Physics hosted the 5th LISA Cosmology Working group meeting. This group has been formed to develop and inform on the cosmological science that can be conducted with the upcoming space-based gravitational wave detector called LISA.

The LISA mission will be formed of three satellites in an equilateral triangle separated by millions of kilometres following the Earth in an orbit around the Sun. The detector will be sensitive to a large range of sources, ranging from mergers of supermassive black holes in galactic centres to exotic objects such as cosmic strings formed in the early universe.

The meeting began with an update on the current status of the development of the LISA consortium. This is the organising body responsible for developing the technology and science for the LISA mission. In particular, we learnt more about the work packages that the Cosmology Working Group needs to carry out in order for the LISA mission to deliver the science it has promised.

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Group members talk in Tampere

View of Tammerkoski in Tampere

Particle cosmologists and astrophysicists from the Universities of Helsinki and Jyväskylä held a joint meeting in Tampere last week. The early spring weather was lovely and the standard of all the talks was very high.

Masters student Lauri Niemi told us about his work on simulating extensions of the Standard Model with non-perturbative methods. Sometimes existing results can be re-used, but in many cases new simulations are required. Part of his PhD studies will involve carrying out those simulations.

Daniel Cutting, visiting us from Sussex, gave a talk about his simulations of vacuum scalar bubbles and the resulting gravitational wave power spectrum. His movies and other visualisations went down very well with the audience.

Sara Tähtinen spoke about gravitational waves from a tachyonic transition, in scenarios where non-Abelian gauge fields play a role. Because non-Abelian gauge fields self-interact strongly, the results are rather different from previous studies of gravitational waves from tachyonic preheating.

Image credit: Jorge Franganillo (CC BY 3.0) [source].

Summer jobs in computational field theory and gravitational waves

Log-scaled kinetic energy for a simulation of a first-order phase transition in a field-fluid model.

We are looking for 1-2 summer trainees with a background in theoretical physics and preferably with good programming skills. The positions are for three months, with exact dates to be agreed upon.

We study theories of particle physics using large-scale numerical simulations, usually applied to cosmology. In particular, our research topics include gravitational wave production in the early Universe, phase transitions in beyond the Standard Model theories, and algorithmic development. The trainees’ research projects are chosen according to the experience and preference of the trainees. The research projects can form the basis for either a Bachelor or a Master thesis.

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