PhD student in Physics - Machine Learning the Universe’s Initial Conditions

The Department of Physics is located in the AlbaNova University Center and has approximately 240 employees, 250 students at undergraduate level and 70 graduate students. There are four research subjects within the postgraduate program: Physics, Theoretical Physics, Chemical Physics and Medical Radiation Physics. These subjects span over several research groups with different research activities. For information about the Department of Physics, see: www.fysik.su.se/english.

Project description

Subject: Physics

We are searching for an outstanding PhD candidate with a high intrinsic motivation to study the origin and evolution of cosmic structure using galaxy surveys and cutting-edge data science methods. The applicant should have experience or an interest in cosmology, programming and machine learning, and other relevant skills. The position requires fluency in spoken and written English to participate in international research collaborations and publish scientific articles.

The origin of cosmic structures and the cause of the Universe's accelerating expansion are significant open problems of modern cosmology, indicating the need for new physics to describe nature. According to the Standard Model of Cosmology, all observable structures in the Universe originated from tiny primordial quantum fluctuations, which grew gravitationally to form the presently observed distribution of galaxies. Understanding the origin and formation of these cosmic structures will provide new insights into the true nature of dark matter, dark energy, gravity, and the yet-unknown high-energy processes governing the beginning of the Universe.

The successful candidate will work with Dr Jens Jasche to develop and apply novel statistical and deep learning methods to reconstruct the 3D initial conditions of observed cosmic structures in galaxy surveys and trace their gravitational formation history across time. This project will use novel cosmological simulations and data from the Sloan Digital Sky Survey, the next-generation Rubin Observatory, and the Euclid satellite mission to explore the link between initial conditions and the nonlinear gravitational processes shaping the observed distribution of galaxies. Cosmic structure reconstructions will then be used to test physics models of dark matter, dynamic dark energy, and the theory of cosmic inflation.

The project is funded by the Simons Foundation through the 'Learning the Universe' Collaboration (www.learning-the-universe.org), which provides the successful candidate with ample opportunities to interact with our collaborators at participating institutions (Columbia University, Lawrence Berkeley National Lab, Harvard University, Flatiron Institute, Institut Astrophysique de Paris, Université de Montreal, Princeton University, Carnegie Mellon University, MPA Garching). The successful candidate will further be a member of our Aquila consortium (www.aquila-consortium.org), an international research collaboration developing novel data science techniques to study fundamental physics with cosmic structures.

Qualification requirements

In order to be admitted to postgraduate education, the applicant must have the general and specific entry requirements. The qualification requirements must be met by the deadline for applications.

You meet general entry requirements if you have completed a second-cycle degree, or completed courses equivalent to at least 240 higher education credits, of which 60 credits must be in the second cycle, or have otherwise acquired equivalent knowledge in Sweden or elsewhere.

Specific entry requirements. In order to be accepted as a PhD student in Physics or Theoretical Physics a BSc in Physics (or equivalent) is required. The studies must include 60 credits of second-cycle courses in physics out of which at least 15 credits correspond to a second-cycle degree project. The degree project does not have to have been examined at the application deadline, but work corresponding to half a semester of full-time studies should have been devoted to it. For the subject Chemical Physics courses in chemistry may replace the required physics courses. The subject Medical Radiation Physics requires a second-cycle degree project of 30 credits in the subject area, or with 60 credits of physics, a second-cycle degree project of 30 credits in another subject area.

In addition, proficiency in English language, equivalent to English B in Swedish high school, is required, or

• Previously completed University degree taught in English
• IELTS score (Academic) of 6.0 or more (with none of the sections scoring less than 5.0)
• TOEFL score of 550 or more (computer based test 213, internet based 79)
• Cambridge/Oxford - Advanced or Proficiency level.

Selection

The selection among the eligible candidates will be based on their capacity to benefit from the training. The following criteria will be used to assess this capacity:

• documented knowledge in a relevant field of research
• capacity for analytical and creative thinking
• initiative
• independence
• ability to collaborate
• written and oral proficiency in both Swedish and English.

Admission Regulations for Doctoral Studies at Stockholm University.

About the employment

We offer a fixed-term employment as a doctoral student according to Chapter 5 of the Higher Education Ordinance (1993:100). The period of employment may not be longer than what corresponds to full-time doctoral education for four years. As a doctoral student, you should primarily devote yourself to your own doctoral education, but the employment may include work with education, research and administration to a limited extent (maximum 20 %).

A new employment as a doctoral student is for a maximum of one year, the employment is then renewed for a maximum of two years at a time.

Stockholm University strives to be a workplace free from discrimination and with equal opportunities for all.

Contact

For more information about the project, please contact Prof. Jens Jasche, jens.jasche@fysik.su.se.

For information about the employment Prof. Michael Odelius, odelius@fysik.su.se, who can also forward questions to the PhD student council at Fysikum.

Application

Apply for the PhD student position at Stockholm University's recruitment system. Attach a personal letter and CV as well as the attachments requested in the application form. It is the responsibility of the applicant to ensure that the application is complete in accordance with the instructions in the job advertisement, and that it is submitted before the deadline.

The instructions for applicants are available at: How to apply for a position.