Is astronomy a useful science?
You may be one of those people wondering why on Earth would we care about the study of black holes, neutron stars, gamma-ray bursts or galaxies. This is indeed a question I get often times after explaining I study the interaction of black holes and neutron stars with their environment. And rightfully so, after all, those things are millions of light-years away and it is far from obvious how studying them can lead to any practical impact on our everyday life. I have even heard some colleagues acknowledging that their time could be best devoted solving real-world problems or more mundane matters. In other words, they do seem to think to some extent that their research is not very useful. All this has led me to ponder whether what I do is actually meaningful, and the first conclusion I came to is that asking about the practical implications of fundamental research is starting off on the wrong foot.
Asking the right questions
My previous self would have argued that the importance of fundamental research lies on the usual premise that it often fuels technological innovations: Einstein’s theory of relativity was deemed useless until the Global Positioning System (GPS) needed it to correct for gravitational time dilation to function accurately, the European Organization for Nuclear Research (CERN) developed the World Wide Web — the thing you are using at this very moment — when in need for a global and fast system to transfer information between researchers and lasers would not be around without our understanding of quantum mechanics. Yet these arguments, while important, are aimed at answering the wrong question.
To illustrate why, consider the following questions: Is the COVID-19 vaccine harmless? Are driverless cars safe? While these may seem like valid questions at first, they fail to see the bigger picture. Inoculation is not risk free and cannot be 100% harmless by definition, so a better question would be: Does the COVID-19 shot outweigh the risks induced by COVID-19 — both for the individual and for the society? Similarly, asking whether driverless cars are safe assumes humans are perfect drivers, when in reality we are terrible drivers. A better question would have been: Are driverless cars safer than humans? Only when we ask the right questions we can start to debate whether these solutions — the COVID-19 vaccine or driverless cars — are worth pursuing.
Similarly, asking for real-world applications to fundamental research misses the point. Because technological innovations have a direct impact on the way we live, we tend to think more easily about them when thinking about research. Yet consider the tremendous philosophical shift that heliocentrism — the astronomical model that superseded geocentrism, placing the planets around the Sun instead of the Earth at the center of the Universe — meant for humanity. Or ask yourself: do I want to live in a world where we think we know the Earth is at its center when it is not, or one where we know — as far as we can tell — the Earth is in an unexceptional place in the Universe? Similarly, the realization that the Universe is expanding supposes a vastly different perception of reality compared to one where the Universe is static and ever-existing. In both of these examples your everyday life remains unchanged, but the implications in the way we think about our place in the Universe are a reflection of the true power of fundamental knowledge.
Fundamental research has simply a different objective than seeking practical applications, it seeks to expand our knowledge and understanding by leaving the filtering effects of our senses aside. Knowledge sweeps away ignorance and opinion, allowing us to reach a higher perspective from which to contemplate the true being of things. In essence, the modern scientist is the equivalent of the ancient Greek philosopher trying to leave Plato’s cave, and access those eternal and immutable truths hidden to us.
Consider fractal theory, a term coined by the mathematician Benoît Mandelbrot, which provides a mathematical framework to describe roughness and self-similarity, concepts not easily described by Euclidean geometry, Darwin’s theory of natural selection, which may explain how species evolved over time, the Big Bang theory, not the TV show, but the idea that the Universe expanded (and still expands) from a singularity around 13.8 billion years ago, or Einstein theory of General Relativity. These theories or discoveries were not aimed at providing any practical application, yet no one denies they are as important as inventions like the wheel or the printing press, because of the way they have improved our understanding of the world we live in. Given the profound implications of fundamental research, why then, ask for practical implications? Demanding them undermines its importance in revolutionizing the way we think about the world, in generating new ideas and in stimulating new ways of thinking.
So the study of black holes billions of light-years away is simply another tiny step in making sense of our most distant surroundings. Their study has obviously its relevance in an astrophysical context, but justifying its importance in terms of practical applications is yet another failure to see the profound implications of fundamental knowledge.
The problem with astrophysics
Why is it that sciences such as mathematics or biology have it easier to justify their purpose, than astrophysics? Why is it that discovering that black holes are among the most powerful X-ray sources in the Universe seems irrelevant? Why does, let’s say biology, seem more easily justifiable research than astrophysics, even if both may not be pursuing real-world applications? In my opinion, the reason is because of our conception of what the world means. This concept is heavily limited by our everyday life experience, because we tend to think of the world as the Earth we live in, yet why limit our vision to this tiny fraction of the true space in which we inhabit? Astrophysicists, much like mathematicians, biologists, chemists, etc. are also trying to understand the world, but their conception of what the world means is all-encompassing, it’s the vast Universe.
Think that each one of those stars you see in the night sky is just another Sun shining hundreds of light-years away, and that each star might have its own planetary system much like ours. Now realize that all these systems you are observing actually belong to our own Galaxy and that there exists billions of galaxies with billions of stars with planetary systems around them. With this perspective, limiting our research to the world around us seems like a foolish idea, and one can start to grasp the true importance and relevance of astrophysical research in understanding our place in the Universe.
The practical answer
Hopefully at this point you are convinced that fundamental research is worth pursuing per se, without a practical end goal in mind. But this might have left you unsatisfied, because you came here looking for answers. Well, luckily for you, I do have an answer but it requires a great deal of imagination. This answer was partly inspired by the sci-fi documentary or docufiction — didn’t even know that was a thing — Alien Worlds on Netflix, which I highly recommend.
It is often argued that the technological advancement of a civilization can be measured by the amount of energy it is able to harness. Consider that for over 200,000 years fire was our only source of energy, while now we can tap into the Sun’s energetic output in an efficient manner to power our appliances and transportation system. And this energy consumption will only increase over time —just think about the energy needed to power the digital transformation: from money to the metaverse. The graph below illustrates this, as it shows how the global energetic consumption is steadily increasing every year.
Yet our yearly energetic consumption is roughly the amount of energy that the Sun sends to Earth in an hour. According to the technological scale defined by soviet astronomer Nikolai Kardashev, this places us in a Type I civilization, since we are not yet able to harness all the energy our star provides to us. As our species becomes a multiplanetary one, we will require new and more powerful energy sources to fuel our civilization, such as supermassive black holes. Black holes are enormous gravitational wells attracting gas, which slowly spirals onto them and acquires tremendous amounts of energy, released as radiation across the entire electromagnetic spectrum. The energy produced around a supermassive black hole in this manner can surpass the energy produced by the billions of stars in a galaxy. A sufficiently advanced civilization — Type II and III — could harness this energy to fuel its exploratory journey through the Universe, much like today we harness the energy from our Sun. So the study of black holes, and other powerful energy sources such as neutrons stars, gamma-ray bursts and fast radio bursts, may prove valuable in the far distant future.
And while becoming a multiplanetary species still remains in the realm of science fiction, in my opinion it is one of the most crucial aspirations of mankind as a species. As Russian rocket scientists and one of the fathers of astronautics Konstantin Tsiolkovsky beautifully put it: “The Earth is the cradle of humanity, but mankind cannot stay in a cradle forever”. Earth is not our home, but rather our birthplace and as such, we should shoot for the stars. And if this isn’t reason enough, the existential risks that threaten to wipe out humanity — nuclear war, climate change or the development of new technologies such as AI or biotechnology — should be more than sufficient.