Modelling galaxies and black holes may reveal new aspects of the universe. Astrophysics stretches the limits of science and engineering, says Doctoral Researcher Alexander Rawlings.
The mechanisms of the universe work in varying scales over tens, thousands and billions of years. Even microscopic events can have great effects.
"What makes this difficult is that things take place over such long periods of time. Looking at the universe now, we catch only the blink of an eye in the many stages of a continuum," says Alexander Rawlings.
Rawlings is in the second year of writing a doctoral thesis in theoretical extragalactic astrophysics at the University of Helsinki. In other words, he studies the universe outside the Milky Way by means of mathematics and physics.
Stars, exoplanets and galaxies as research topics
Rawlings completed a bachelor's degree in physics in Australia. At the University of Sydney, he was admitted to a traineeship where he contributed to extragalactic observational research focused, with the help of telescope data, on the special features of galaxies.
Rawlings applied to several master's programmes and ended up moving to a country on the other side of the globe. In the Master's Programme in Particle Physics and Astrophysical Sciences, at the University of Helsinki, he specialised in astrophysics.
Like Rawlings, many graduates of the master's programme continue their studies and research. He believes the programme deepened his capacity for critical thinking and provided practical skills, such as programming and statistics. Outside academia, they enable employment in government administration, the financial sector and the world of consulting.
"I learned about black holes and supernovae, but above all I learned about the process I went through to understand them, that is, methodology."
The complex relationship between galaxies and black holes
According to Rawlings, the handprint of astrophysicists is not tangibly evident in everyday life, as are bridges designed by engineers. However, it helps us perceive our place in the universe.
"Our research helps us understand why we are here and what our future in the galaxy looks like."
Rawlings investigates galaxies and black holes, which have a close but complex connection between their origin and development.
A supermassive black hole is believed to lie in the centre of most galaxies, including our Milky Way. Their mass can be millions or billions of times that of the Sun.
"We see that the two have a relationship, but we don't understand the nature of that relationship well enough. Our research group uses a code we have designed to model the interaction of the black hole with its surroundings."
On the boundaries of knowledge, science and engineering
Rawlings believes the results of research must be available to all. A recent example is the James Webb Space Telescope, launched in December 2021. Its first publicly shared images depicted the furthest objects in space, which Webb's predecessor Hubble is unable to observe.
"You don't have to understand the formation of stars or the evolution of galaxies to be able to look at the images and get excited about them. Decades of effort by physicists and engineers underlie the images."
In fact, research requires complex mathematical systems and computational devices. Researchers are stretching the boundaries of knowledge, science and engineering, as they need increasingly complex computers to model the relevant processes.
On Earth, we are also struggling with the climate crisis and other serious trends. By studying the surrounding universe and planets, we will learn what will happen if global warming is not slowed.
On Earth-like Venus, the greenhouse effect was able to progress unbridled. That is what Earth could look like in four million years if nothing is done.
Understanding galactic dynamics is part of a whole where the structure of the galaxy affects the number and types of stars, which in turn affects the formation of planets and, indirectly, planets similar to Earth.
"While the link is indirect and perhaps difficult to perceive, understanding the whole can help make informed decisions when navigating the current situation."
