AI is developing faster than people can grasp its importance and risks, says Buchalter Prize laureate

Armenpress spoke to physicist and cosmologist Professor Levon Pogosian, head of the Department of Physics at Simon Fraser University, a public research university in Vancouver, Canada, and an overseas staff member of Byurakan Observatory. Pogosian was a 2021 laureate of the prestigious Buchalter Cosmology Prize. The interview focused primarily on questions surrounding the expansion of the universe, but also covered the prospects for science in Armenia and the rapid development of artificial intelligence.

Pogosian was born in Yerevan and graduated from the Faculty of Physics at Yerevan State University, specialising in theoretical physics. In 1993, he moved to the United States, where he defended his doctoral thesis at Case Western Reserve University. He went on to work at Imperial College in England and at Syracuse University and Tufts University in the US. He later settled permanently in Vancouver, where he has lived and worked for 20 years.

What scientific question are you studying at present?

I am mainly trying to understand the trends in the expansion of the universe and what causes it. A range of fascinating astronomical observations, including observations of galaxies, are now available from international organisations that have used various observatories. The results are openly available, and any specialist can use them in their own research. I am mainly interested in studying what is known as dark matter. There are two components of the universe that remain unexplained: dark matter and dark energy. Together they account for 95% of the energy in the universe. Their nature remains unclear, and that is a major problem. Some very interesting new questions have also emerged recently.

The American astronomer Edwin Hubble discovered that the universe was expanding about 100 years ago. The problem, however, is that different methods of calculating the rate of expansion give us different results. We are talking about the Hubble constant. (Editor’s note: This is the coefficient in the law named after Edwin Hubble that relates the distance to an object outside our galaxy, such as another galaxy or a quasar, to the speed at which it is moving away.) This means there is still something very important we have not understood in our theory.

You mentioned that there are different estimates of the rate at which the universe is expanding. Can you give us a rough figure?

Hundreds of kilometres per second.

How fast is that by cosmic standards?

It is fast, and the acceleration keeps increasing. In other words, the universe continues to expand at an ever-increasing rate.

What could that lead to? Could there be another Big Bang?

No. The expansion of the universe means that other galaxies are moving away from us. Now imagine that they are moving away faster and faster. If they move away faster than the speed of light, at some point we will no longer see their light. The distant galaxies we are studying today may no longer be visible in about 100 million or a billion years. I am not talking about the foreseeable future, so there is no cause for alarm. But 100 million years is not a long time on a cosmic scale.

Does expansion release energy, and could we use it to meet our needs on Earth?

No way of doing that has been found yet, but that does not mean it never will be. We currently assume that the acceleration of the expansion comes from vacuum energy. In effect, even nothingness, what we call a vacuum, has energy, even if there is no air and there are no particles. If we can understand it, who knows? Perhaps we will be able to use that energy.

Even for specialists, it is difficult at first to grasp how nothingness, a vacuum, can have energy. We know that as the volume of matter increases, its density falls. In this case, observations show that the universe is expanding, but its density does not change: the density of dark energy remains constant. It is very difficult to find another example like this in physics. Only a vacuum can have this property. That nothingness, that airless space we call a vacuum, has energy whose density does not change. Remaining constant is one of the properties of a vacuum.

To understand this, we will probably need to turn to quantum field theory and the general theory of gravitation, which do not yet exist. Cosmological research is one way for us to arrive at those theories. If we can understand gravity and the mechanics of quantum fields, we will be able to understand and describe the vacuum and work out how to obtain and use that energy.

Are people already trying to solve that problem?

Leading specialists, starting with Einstein, have been trying to understand it for about half a century. I think a clever idea that helps solve it could come at any moment. I think humanity is simply waiting for it. Observations help, of course, but we need a fresh approach.

As the universe expands, is our galaxy simply moving away from other galaxies, or is it also changing its position relative to them?

Its position relative to the others is changing. This is very important to emphasise, because there is no change in the positions within our galaxy: gravity holds all the objects in our galaxy together.

Does that prevent a possible global catastrophe?

In the unimaginably distant future, when the matter in all the stars has burnt up and been destroyed and everything has turned to dust, our galaxy may begin to expand too, which would lead to the disappearance of the remaining matter. But before that can happen, our galaxy’s enormous store of energy must burn away and be exhausted. Only then will the expansion of the universe affect our galaxy in any way.

Coming back to the present, do you work with scientific institutions in Armenia on your research?

Byurakan Observatory has a different scientific focus. It mainly studies stars and does not investigate the overall expansion of the universe. But I have colleagues at the Physics Institute and Yerevan State University who work on this question, and we are carrying out some projects together. We also plan to offer courses for master’s students and establish an international platform for doctoral studies, so that our young people can defend their theses, carry out research with help from leading specialists abroad and join the international scientific community.

Based on your contacts and observations, how do you assess Armenia’s scientific potential in astronomy and cosmology?

It is difficult to give a definitive answer, but my impression is that our young people are as well educated and knowledgeable as their peers in other advanced countries. Many simply prefer to work outside science, in fields such as IT and artificial intelligence, where there are plenty of jobs and the pay is considerably higher. Even so, Armenia has considerable scientific potential.

I am pleased to say that one of these talented young people will soon defend a thesis and continue their studies in Vancouver. I met this student and two other young people from Armenia this winter in Poland, where astronomer Professor Armen Sedrakian runs a specialised school every year. They are master’s students at Yerevan State University. We want to help increase the number of talented young scientists in Armenia. I think that if we can give them clear prospects and opportunities to do substantial research at an international level, we can reach a new level in the quality of our scientific work. It is also very important to draw on the expertise of Armenian scientists who live and work in the diaspora.

How do you assess the role and importance of artificial intelligence in science?

It is a wonderful tool, and I use it myself. AI is developing faster than people can grasp its importance and risks. Mathematicians recently expressed some concern about the rapid development of AI after it managed to solve a very difficult problem. Many people are now trying to understand what that means for science and for humanity as a whole. I do not think there is an answer to that question yet.

Will there come a time when AI pushes people out of science altogether because they cannot compete with machines?

I can say with confidence that the role of people in science will change, but it will not disappear altogether. Many things we do now will simply no longer serve a purpose. People will always have a role in science.

Traditional forms of education may change. Students may no longer need to go to universities to listen to lectures and take notes. They could do the same at home, listening to lectures on the relevant subject prepared and delivered by AI and completing the homework assignments it suggests. But that does not mean universities will no longer be needed. Universities will need to rethink how and what they teach and offer what AI still cannot. For example, they can adopt creative, practical approaches based on people working together and interacting directly. That is very important.