Time may not exist at all – Is there time? The answer to this question may seem obvious: of course there is! Just look at the clock or the calendar.
However, the development of physics suggests that the absence of time is an open possibility, an issue that needs to be taken seriously.
How can this be so and what does it all mean? It takes time to explain, but do not despair, even if there is no time, our lives will still go on as usual.
Crisis in physics
Physics is in crisis. Over the past century and beyond, we have been able to explain the universe through two highly successful physical theories: general relativity and quantum mechanics.
Quantum mechanics describes how objects work in an incredibly sparse universe of particles and particle interactions. General relativity describes the big picture of gravity and the motion of objects.
Both theories work very well separately, but are thought to contradict each other. However, the exact nature of the conflict is debatable, and scholars generally agree that both of these theories need to be replaced by new, more general theories.
Physicists want to develop a theory of “quantum gravity” that replaces general relativity and quantum mechanics and achieves the remarkable success of both. Such a theory should explain how the big picture of gravity affects the miniature scale of particles.
Time in quantum gravity
It seems that formulating the theory of quantum gravity is extremely difficult.
One of the attempts to resolve the conflict between these two theories is string theory. String theory replaces particles with strings that vibrate in a maximum of 11 dimensions.
However, string theory faces even more complexity. String theory offers a variety of models that broadly describe a world like ours and do not make any obvious predictions that could be experimentally tested to find out which model is correct.
In the 1980s and 1990s, many physicists were dissatisfied with string theory and put forward a range of new mathematical approaches to quantum gravity.
One of the most prominent of these is the loop quantum gravity, which suggests that the fabric of space and time is made up of extremely small intermittent pieces, or networks of “loops.”
One of the distinctive aspects of loop quantum gravity is that it completely excludes time.
Loop quantum gravity is not the only one that denies time: several other approaches also reverse time as a fundamental aspect of reality.
Generation of time
Therefore, we know that we need a new physical theory to explain the universe, and in this theory time may not be represented at all.
Suppose such a theory proved correct. Does this mean that time does not exist?
It is a difficult issue and depends on what existence means.
Theories of physics do not include any tables, chairs, or people, but we still agree that tables, chairs, and people exist.
Why? Because we assume that such objects exist at a higher level than the level described by physics.
For example, we say that tables “originated” from the basic physics of spinning particles in the universe.
Although we may know quite well how a table is made up of fundamental particles, we have no idea how time can be “made up” of something more fundamental.
Consequently, until we can draw a good conclusion about how time arises, it is incomprehensible to simply assume that time exists.
Time may not exist at any level.
Time and acting
To say that time does not exist at any level is like saying that tables do not exist at all.
Proving a world without tables can be difficult, but taking time out of a world without time can be a daunting task.
Our whole life is time-based. We plan for the future based on what we know about the past. We judge people morally according to their past actions in order to reprimand them later.
We think of ourselves as agents (entities that can do things) in part because we can plan our actions so that they can bring about change in the future.
But what is the point of an action that should bring about change in the future if there is no future for that action?
What is the point of punishing someone for an action committed in the past if there is no past and therefore no action?
Discovering that there is no time would confuse and stop the whole world. We would not even have a reason to get out of bed.
As usual activities
There is a way out of the mess.
It is true that physics can deny time, but it seems to leave causality intact: the perception that one thing can lead to another.
Then physics probably tells us that the basis of the future of the universe is causality and not time.
If this is the case, the activity can be saved. Whereas it is possible to reconstruct the sense of action entirely from a causal point of view.
At least that is what physicists Christy Miller, Jonathan Talent and Sam Baron believe in their new book, Beyond Time.
They think that discovering that there is no time may not have a direct impact on our lives, even though it would start a whole new era in physics.
Prepared according to The Conversation.
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