What is your name, affiliation, academic position, and job title?
My name is Oleksii Sokoliuk, I am a research scholar at the Main Astronomical Observatory, National Academy of Sciences of Ukraine, and undergraduate student at the University of Aberdeen, UK.

What is your journey?
I was living in Ukraine for most of my life, but had to move several years ago to Scotland due to the war with the Russian Federation.

What is your field of research and/or what project are you involved in?
I am working in the field of theoretical cosmology – trying to find new probes of modified gravitation (MOG theories in turn sometimes can alleviate some tensions in cosmology, which is a goal of current COST Action) within higher-order statistics (N-point correlation function, polyspectra, etc.) and perform simulations of the universe from it’s very beginning to the present times. Currently, I have several projects, namely the LANCELOT project – a large set of N-body simulations within cosmologies beyond LCDM, Condor project – an emulator of non-linear features in matter power spectrum within Jordan-Brans-Dicke gravitation. Also, I am running lattice simulations of preheating to reduce inflationary landscape.

Briefly describe your career trajectory to date. What positions have you held, when and where?
Since I can be considered a very young researcher, up to date I only worked as an observer of comets, NEOs, and variable stars in Taras Shevchenko National University of Kyiv from 2019 and as a member of the lab for the Large Scale Structure of the Universe in the MAO NASU from 2021 to the present time. Now I am also working in a Quantum Gravity and Gauge Theory Group at the University of Aberdeen with Prof. Charles Wang starting in September this year.

What are your research plans?
In the near future, I am planning to finish both LANCELOT and Condor projects and begin a new project that will incorporate complex N-body+SPH simulations with EAGLE subgrid physics (stellar, SN I/II, AGN feedback, primordial abundances of 12 elements, UV cooling, etc.). This project would require a large amount of preparations, and modifications to the various codes and will involve many collaborators (some of which are participating in the CosmoVerse COST Action).

How does CosmoVerse fit within those plans?
Most of my projects are tightly connected to the cosmological tensions and therefore they are performed under the CosmoVerse COST Action. This Action already helped me to gain visibility by sponsoring my visit to the CCP2023 conference in Japan as well as CosmoVerse@Lisbon in Portugal. I am planning to contribute to the action regularly until its completion.

Which of your skills are you most proud of, or find most useful?
Out of the soft skills, I consider myself to be a very adaptable person and I think that my teamwork is on a good level as well. Among the hard skills, the one that I am most proud of is the ability to run the N-body simulations and to modify the code that runs them – modifications of background cosmology may lead to many interesting and unexpected results!

What new skills would you like to learn in the next year?
Various Machine Learning algorithms that nowadays become very popular within the astrophysics/cosmology community.

What are the most exciting open questions in your research area?
Among the numerous problems and open questions that modern cosmology has, I find that the cosmological tension problem and BBN abundance problems are the most exciting since both problems propose that some kind of modifications should be made to fiducial cosmology and that maybe there are some new physics present.

What advances or new results are you excited about or looking forward to?
I am waiting for the first data release of Euclid/DESI surveys and for the launch of LSST since joint data from all three missions would be able to provide a graph of galaxy correlation function with unprecedented precisions and it would be possible to apply strict constraints on cosmologies beyond Lambda CDM using this calibration function and N-body simulations.

What is your view on cosmic tensions? How does your work connect with this open question in the community?
It is believed that cosmological tensions could be resolved in several ways – firstly by improving the systematics of the SH0ES Pantheon dataset and secondly by modifying the theory of cosmology itself. Generally, I think that tensions arise because of the incompleteness of the Lambda CDM model and that a new, more rigid model should be proposed. I do not believe that such a simple model as LCDM can describe our universe the best (see the complexity of a Lagrangian of a Standard Model of particle physics). Some of my papers are directly related to the study of cosmological tensions in modified theories of gravitation with the use of Markov Chain Monte Carlo codes, while other ones are indirectly addressing the issue of cosmological tensions (for example, my upcoming emulator project).

In your career so far, at what point were you the most excited, and what were you excited about?
Without a doubt, the most exciting moment of my academic life was when my first paper was accepted to EPJ C. I was only 16 years old at that time and could not believe that it really happened.

What is the biggest obstacle that is slowing down your research field right now?
Age. Because of my age and that I am an undergraduate student, most of the opportunities for me are not available, such as internships. I also cannot apply for funding, and therefore it is hard to attend conferences (but I was able with the help of an ITC Grant from CosmoVerse).

What role do you think a community network like CosmoVerse can play in developing theoretical astroparticle physics and cosmology?
A very significant one, that is for sure. Such a community network as CosmoVerse helps bring numerous scientists from different countries and social backgrounds, and we are all working on the same question – how to alleviate the cosmological tensions and what are we doing wrong? Such strong collaboration is practically not possible without actions like CosmoVerse, since inter-university collaborations usually cannot provide such strong grounds for discussion, while CosmoVerse annually organizes conferences, where action members can discuss the advances that have been made in a year and plan future projects together.

What do you like and dislike about being a scientist?
I really enjoy how international academia really is – you get to travel a lot sometimes on a long-term basis (internships, postdoctoral fellowships, etc.) and in practically every university in the world you will encounter many foreign professors, which is great!
I don’t like that the further you progress with your academic career, the fewer opportunities you have to do the actual research and the more paperwork you have to do, as well as the teaching. Also, now you can’t work on some very complicated subject for years as it was centuries ago – it is expected that you will publish papers regularly in international journals so it is more beneficial to choose easier topics to do research on.

What’s your favourite food? Why?
Ramen/Miso, Kimbap, and Deruni (a Ukrainian simple dish). I love Asian food, due to the range of flavours and spiciness but also I adore Ukrainian cuisine.

Your favourite scientist and/or science fiction film?
Kip Thorne is my role model – Interstellar, a film that was produced under his supervision gave me the inspiration to become a physicist and his work on Morris-Thorne wormholes was the foundation of my first-ever published paper.

How do you relax after a hard day of work?
Usually, I would have a walk in a park that I live close by or play some games on my Xbox.

What non-physics interests do you have and want to share?
I love travelling, hiking, and swimming. Also, as a hobby, I am doing astrophotography at night.

If you were not a scientist, what do you think you would be doing?
Data Science was my first choice before I discovered my love of astronomy

What do you hope to see accomplished scientifically in the next 50 years?
Development of a theory that supersedes fiducial Lambda CDM one. Such a theory should relieve all of the tensions present (H0, sigma8, Ly-a, etc.) and offer better fits to the observational data at high redshifts (it is actually very important due to the soon-to-be-launched missions, such as Euclid, DESI and LSST that will map the universe up to very high redshifts and will provide much tighter constraints on cosmological parameters). Also, I hope to see how humanity will colonize Mars and Moon, and construct the first continental map of an Earth-like exoplanet.

In your view, what’s the most important challenge that humanity faces currently?
Global Warming, numerous wars that can lead to the irreversible destruction of the Earth’s atmosphere, flora and fauna.

What question would you have liked us to ask you, and what would you have answered?
Q: Would we be able to discover the Theory of Everything?
A: I hope not, I won’t have any job to do then!