Are there unanswerable questions?
Or can scientists, through their remarkable ingenuity and inventiveness, answer all questions related to physical reality?
Since Thales of Miletus wondered about the material composition of the world some twenty-five centuries ago, a sense of invincibility has characterized the rational quest for knowledge: given enough time, Nature’s secrets will all be revealed to us.
And indeed, as Galileo framed his telescope on the silvery disk of the Moon in 1609, the pace of scientific discovery has been remarkable and inspiring. We have learned much about the nature of the universe, the composition of the stars, the origin of our solar system and of the chemical elements, the inner workings of the atom and of the fantastic metamorphoses of matter into energy and back that characterize the world of subatomic particles. There are also all the discoveries in the biological sciences that I am leaving out.
Science has completely reshaped the landscape of human culture. As a result, our worldview has changed with it. Throughout the past four centuries, two fundamental paradigms ran hand-in-hand, feeding on each other: that it is possible to study the behavior of complex systems by reducing them to their smallest constituents and then work our way from the bottom up; and that the laws of Nature spring from symmetries writ deep into the fabric of space, time, and matter. Our description of physical reality is anchored on the relationship between reductionism and symmetry.
Can it go all the way down to the beginning of Creation?
No question mirrors humanity’s age-old yearning for understanding as deeply as the mystery of creation. Every culture that we know of, past and present, has tried to make sense of our origins. Through their narratives, creation myths define the beliefs and faith of a community. Invariably, in order to explain the origin of everything, these myths make use of a transcendent force, an absolute power which exists beyond the confines of space, time, and matter. Gods, being supernatural entities, are not subject to the constraints of physical laws. Thus, to explain how the world and life came to be, creation myths assume the existence of a parallel reality, which may interact with ours but that exists outside of it.
Science, of course, cannot make use of supernatural entities to explain the mechanisms of the natural world. How to explain Creation within the rational logic of Nature? (The capital “C” stresses that by Creation I mean the origin of all there is.)
During the twentieth century, the question of origins received renewed attention. If, as Einstein’s general relativity has shown, space-time is plastic, and if, as quantum mechanics has shown, there is a fundamental limitation as observers try to extract information about the material world, it follows that, as we attempt to combine quantum mechanics with relativity, the very structure of space and time must be reinterpreted. In particular, within the framework of the big bang theory, as we travel backwards in time, we must understand how quantum gravity will confront the existence of a classical singularity: the problem of the first cause enters the quantum realm.
Models of quantum cosmology, creative and elegant as they are, do not solve the problem of the first cause. Neither do superstring cosmologies, that is, models of the origin of the universe inspired by superstring theories.. Any scientific description of natural phenomena which lies beyond the empirically tested must, by construction, rely on a series of unproved assumptions. In the case of quantum cosmology, we use certain physical laws—such as the law of conservation of energy-momentum and of charge—well beyond their currently known limit of validity. In other words, we are using a theoretical framework that relies on the general theory of relativity and on quantum mechanics well beyond the scales where these theories are known to work.
This is not, as some readers may think, a surmountable problem, that will go away as we discover more and more of the natural world and extend the validity of our physical models to higher and higher energies. It is also not “business as usual,” in the sense that science naturally progresses as we continually strive to test theories beyond their limits of validity. Here, the question is of a different nature; there is a fundamental limitation in trying to construct a physical theory based on notions of causation and of quantum indeterminacy to deal with the first cause.
Every equation embodies an implicit conceptual structure. Science needs a scaffolding, a structure upon which to operate. It cannot explain the first cause because it cannot explain itself. It’s not enough to say that all is encapsulated in the multiverse, this hypothetical collection of all potential universes, including ours. The question of where did the multiverse come from will always remain. Even if a consistent model of the origin of the universe is formulated one day, it will still be a scientific model of creation, unable to explain its own structure. The first cause is an a priori limitation of any rational explanation of reality. It may be an unanswerable question about nature.
Or can scientists, through their remarkable ingenuity and inventiveness, answer all questions related to physical reality?
Since Thales of Miletus wondered about the material composition of the world some twenty-five centuries ago, a sense of invincibility has characterized the rational quest for knowledge: given enough time, Nature’s secrets will all be revealed to us.
And indeed, as Galileo framed his telescope on the silvery disk of the Moon in 1609, the pace of scientific discovery has been remarkable and inspiring. We have learned much about the nature of the universe, the composition of the stars, the origin of our solar system and of the chemical elements, the inner workings of the atom and of the fantastic metamorphoses of matter into energy and back that characterize the world of subatomic particles. There are also all the discoveries in the biological sciences that I am leaving out.
Science has completely reshaped the landscape of human culture. As a result, our worldview has changed with it. Throughout the past four centuries, two fundamental paradigms ran hand-in-hand, feeding on each other: that it is possible to study the behavior of complex systems by reducing them to their smallest constituents and then work our way from the bottom up; and that the laws of Nature spring from symmetries writ deep into the fabric of space, time, and matter. Our description of physical reality is anchored on the relationship between reductionism and symmetry.
Can it go all the way down to the beginning of Creation?
No question mirrors humanity’s age-old yearning for understanding as deeply as the mystery of creation. Every culture that we know of, past and present, has tried to make sense of our origins. Through their narratives, creation myths define the beliefs and faith of a community. Invariably, in order to explain the origin of everything, these myths make use of a transcendent force, an absolute power which exists beyond the confines of space, time, and matter. Gods, being supernatural entities, are not subject to the constraints of physical laws. Thus, to explain how the world and life came to be, creation myths assume the existence of a parallel reality, which may interact with ours but that exists outside of it.
Science, of course, cannot make use of supernatural entities to explain the mechanisms of the natural world. How to explain Creation within the rational logic of Nature? (The capital “C” stresses that by Creation I mean the origin of all there is.)
During the twentieth century, the question of origins received renewed attention. If, as Einstein’s general relativity has shown, space-time is plastic, and if, as quantum mechanics has shown, there is a fundamental limitation as observers try to extract information about the material world, it follows that, as we attempt to combine quantum mechanics with relativity, the very structure of space and time must be reinterpreted. In particular, within the framework of the big bang theory, as we travel backwards in time, we must understand how quantum gravity will confront the existence of a classical singularity: the problem of the first cause enters the quantum realm.
Models of quantum cosmology, creative and elegant as they are, do not solve the problem of the first cause. Neither do superstring cosmologies, that is, models of the origin of the universe inspired by superstring theories.. Any scientific description of natural phenomena which lies beyond the empirically tested must, by construction, rely on a series of unproved assumptions. In the case of quantum cosmology, we use certain physical laws—such as the law of conservation of energy-momentum and of charge—well beyond their currently known limit of validity. In other words, we are using a theoretical framework that relies on the general theory of relativity and on quantum mechanics well beyond the scales where these theories are known to work.
This is not, as some readers may think, a surmountable problem, that will go away as we discover more and more of the natural world and extend the validity of our physical models to higher and higher energies. It is also not “business as usual,” in the sense that science naturally progresses as we continually strive to test theories beyond their limits of validity. Here, the question is of a different nature; there is a fundamental limitation in trying to construct a physical theory based on notions of causation and of quantum indeterminacy to deal with the first cause.
Every equation embodies an implicit conceptual structure. Science needs a scaffolding, a structure upon which to operate. It cannot explain the first cause because it cannot explain itself. It’s not enough to say that all is encapsulated in the multiverse, this hypothetical collection of all potential universes, including ours. The question of where did the multiverse come from will always remain. Even if a consistent model of the origin of the universe is formulated one day, it will still be a scientific model of creation, unable to explain its own structure. The first cause is an a priori limitation of any rational explanation of reality. It may be an unanswerable question about nature.
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