What have the stars done for mankind?

Professor Roberto Trotta of the Department of Physics at Imperial College London is a theoretical physicist and astrophysicist. His work explores how statistics and machine learning can help us translate complex data sets from Earth and space telescopes into real-life understanding.

About four years ago he gave his inaugural lecture at Imperial College. Now, he is a visiting professor and hopes to enable us to appreciate the sky and the stars. His latest book, Starborn, was recently selected as BBC Radio 4’s Book of the Week.

We caught up with him to find out what the stars, sky, and everything in between have to offer humanity, and why we should work hard to take care of our planet so we can still look up to the stars.

When I think of space scientists, machine learning and big data are not the first things that come to mind. Can you explain why we use big data and artificial intelligence to look at the world above us?

Machine learning and artificial intelligence are critical to understanding our universe. Galileo and others had looked through telescopes and painted what they saw, and a few years later, at the Harvard Observatory, women astronomers were examining hundreds of thousands of stars and galaxies through images. Because of the complexity and scale of our existing data, we need computers to extract scientific meaning from the vast amounts of data collected by telescopes in space and on Earth.

One of the most cutting-edge areas in my field is exactly that. We explore how artificial intelligence (AI) can help us understand the universe. We are getting more and more data all the time, but the question is what does it all mean? This is where statistics and machine learning come in.

Can you explain to me what you were trying to find out and what people might hope to find through this work?

Different people are interested in different things. My research focuses on three main areas: what happened in the first part of the Big Bang, how dark matter and dark energy behave, and understanding what the universe is made of.

The universe is made up of 25% dark matter and 70% dark energy, which together make up 95% of the universe, but we know very little about what they are.

We owe our existence to the gravitational pull of dark matter. It plays a crucial role in the formation of galaxies and stars, especially their rapid formation. We’re pretty sure dark matter exists because we see it affects the way the universe expands and how galaxies move. The question is what is it made of?

Dark energy is harder to explain. We see the universe growing faster and faster, and we think this is caused by repulsive forces, antigravity. This may be due to the properties of void itself; as the universe expands, it creates more vacuum, which in turn creates more repulsive forces, so it expands faster. We think this runaway expansion process is driven by dark energy, but no one knows what it is. We’re working hard to find out.

I can’t understand how you can study the first few milliseconds after the big bang, since that’s a very small time frame for something that happened so long ago. How do you do this?

We now have observations from a very, very early period in the history of the universe, with radiation coming from 380,000 years after the Big Bang. The universe is 13.8 billion years old, so the 380,000 years since its creation are only a fraction of its age. Thanks to these observations, we can almost go back to the very beginning.

We’re pretty sure we can recreate pretty much everything that came before that. But what happens there? this is a big problem.

We think the universe expanded very, very fast, exponentially, over a very short period of time. We call that moment “inflation,” and we try to reconstruct what that small portion of time looked like, and what triggered it.

Although this is much higher than today’s dark energy, its exponential expansion effect is the same. These two things may or may not be connected.

Only 5% of the universe is made of matter like you and me. This is one of the big questions in physics. What’s the rest? Why does it exist? Why is the universe so weird?

What have you discovered so far about the universe and its weirdness?

Science is always a collaborative endeavor, so you have to stand on the shoulders of giants.I have very talented young researchers working with

My team and I hope to answer these questions in a way that uses all the information available in the data and produce results you can trust.

It’s very statistical and computational, and we’re always looking for ways to get this information out of complex data sets.

Your book is about looking up at the stars, which I imagine you’ve done a lot of, and appreciating what the stars do for humanity.

A: Yes, we are all made of stardust, but the stars do so much more for us than that. This book is not about the physical properties of stars or dark matter or anything we have discussed so far. This book tells the story of the cultural impact that looking up at the stars has had on human beings, from the moment Homo sapiens walked out of Africa 50,000 years ago to today’s artificial intelligence. The inspiration and knowledge that stars bring to us is much worthy of our responsibility.

You compared Homo sapiens from 50,000 years ago to artificial intelligence today. Would you say that the influence of the sky and stars is as great as it was 50,000 years ago?

We are losing the sky and our connection to the sky, you may ask does this matter? I think yes, it’s very important. When we lose the sky, we lose awareness of our deep connection to prehistory.

We are busy now, we live in cities, we no longer look up, we no longer care about the stars, 150 years ago you could see the Milky Way from London. Now, you can barely see any stars. Even though I’m in Trieste, Italy, where the sky is dark, you can see a lot of passing satellites, and it’s estimated that by 2030, there will be more satellites than stars.

What happens when we lose our stars?

Lose touch and you lose the significance of our place in the universe and what it means for countless generations. This jeopardizes not just the present, but our future.

We lose the sense that we are a blue dot floating in a vast, desolate dark universe, far removed from any place we could call home.

Our planet is irreplaceable, and without Planet B, we cannot colonize Mars on the time scale we need. We need to work together because losing our stars also means losing ourselves.

Is your goal to get people to look up?

I want people to look up at the stars and think about our trajectory and imprint in the universe. As early as 50,000 years ago, we were changing our environment to suit our needs. Today, people feel threatened by biodiversity loss and climate change. By taking a long-term view of the entire arc of human history and how the stars have guided us, and hoping to look to the stars to provide more inspiration for the future, we should ask, “Where are we headed?” What we need now is not the stars or Mars, But our unique and beautiful place in the universe, on our own planet.

Would it be dangerous for humans if one day we looked up at the sky and saw a vast darkness instead of stars?

It’s not necessarily dangerous, but we’ll all be poorer. Imagine a world where the sky is shrouded in clouds, as I did in A Star Is Born, and no one has ever seen the stars, the sun, or the moon. It might not be dangerous, but it certainly won’t be that rich.

I see you have done a lot of science communication in the past. Is educating others your passion?

This is something I have always done and always felt it was my responsibility as a scientist. I want to give back some of the excitement, enthusiasm, and enthusiasm that we as scientists are privileged to pursue as the main thread of our work.

It’s an honor to share this with the public.

How do you feel about your book being nominated for Book of the Week?

Of course, it’s an incredible honor and I didn’t expect it to be like this. I hope my book will help bust the myth that we can escape to Planet B and contribute to the conversation about the urgency of protecting our planet.

We have to pay attention to what is happening here and now, the next generation will have no stars and possibly no planet to live on. To me, this is an important message.