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If time is not a fundamental feature of the universe, it can still “come out” of something more fundamental (Photo: Shutterstock)
is there time? The answer to this question may seem obvious: of course! Just look at the calendar or the clock. But the development of physics suggests that lack of time is an open possibility and we must take it seriously.
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like him? And what does it mean? It will take some time to explain this, but don’t worry: even if there is no time, our lives will go on as usual.
crisis in physics Physics is in crisis. In the last century, we have explained the universe with two very successful physical theories: general relativity and quantum mechanics.
Quantum mechanics describes how things work in the small sphere of particles and the interactions of particles. The general theory of relativity describes the big picture of gravity and how objects move.
Both theories work very well on their own, but both are thought to contradict each other. Although the exact nature of the conflict is controversial, scholars generally agree that both theories should be replaced by a new, more general theory.
Physicists want to create a theory of “quantum gravity” to replace the general theory of relativity and quantum mechanics, while achieving the ultimate success of both. Such a theory explains how the big picture of gravity works on a miniature particle scale.
Time in Quantum Gravity It turns out that creating a theory of quantum gravity is very difficult. One attempt to overcome the conflict between the two theories is string theory. String theory replaces particles with strings that vibrate in up to 11 dimensions.
However, string theory faces an additional difficulty. String theory provides a variety of models that describe a universe very similar to ours, and does not make clear predictions that can be tested experimentally to see which model is correct.
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In the 1980s and 1990s, many physicists were dissatisfied with string theory and devised a series of new mathematical methods for quantum gravity.
One of the most notable is toroidal quantum gravity, which suggests that the fabric of space and time consists of a network of very small discrete pieces or “rings.”
One of the great aspects of circular quantum gravity is that it seems to completely kill time.
Ring quantum gravity is not the only one in the elimination of time: many other approaches seem to eliminate time as a major aspect of reality.
Time of Appearance So we know that we need a new physical theory to explain the universe, and this theory may not include time. Suppose such a theory is true. Does this mean that time does not exist? This is complex and depends on what we mean by being.
Physical theories do not include tables, chairs or people, but we assume that there are tables, chairs and people. Because? Because we accept that such things exist on a higher level than described in physics.
For example, currents are said to “emerge” from the fundamental physics of particles orbiting the universe.
But while we have a pretty good idea of how to make a table of fundamental particles, we have no idea how to “make” time out of something more fundamental.
So unless we can find a good explanation for how time comes into being, it’s not clear if we can just assume that time exists. There may not be time at every level.
time and agency To say that time does not exist on any level is like saying that there are no tables. Trying to survive in a world without tables can be difficult, but running a world without time seems disastrous.
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Our whole life is built on time. We plan the future in the light of what we know about the past. We hold people morally responsible for their past actions with a view to condemning them later.
We believe that we are agents (entities that can do things) in part because we can plan to act in a way that will lead to change in the future. But what is the point of working for change in the future, when in a very real sense there is no future to work for?
What is the point of punishing someone for past action when there is no past and therefore obviously no action? Discovering that there is no time can stop the whole world. There was no reason to get out of bed.
works as usual
There is a way out of the confusion. While physics can eliminate time, it seems to leave the “cause-and-effect relationship” as it is: the idea that one thing can cause another.
Maybe then physics tells us that causation, not time, is the main characteristic of our universe.
If true, the agency can still survive. Because it is possible to completely reconstruct the feeling of freedom of action from a causal point of view.
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At least that’s what Christie Miller, Jonathan Talent and I discuss in our new book. [Out of Time: A Philosophical Study of Timelessnes, sem edição em português]. We hypothesize that the discovery that time does not exist may not have a direct impact on our lives, even as it pushes physics into a new era.
* Sam Barron is an associate professor at the Australian Catholic University. This article was originally published in English in The Conversation.
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