Does time really exist? Many people think that is a silly question. Don’t you just need to look at the calendar or the clock hanging on the wall to answer?
But more and more physicists are proving to us that they have reason to doubt the real existence of time.
In the 19th century, Albert Einstein and his duo of relativity shook up the notions we once had about time. He proved to us that time is, in fact, made of matter. Time does not exist independently of the universe and only came into being after the Big Bang.
Einstein also proved that in this whole universe time, if anything, is just something relativistic. It passes more slowly for those on board a spacecraft traveling near a massive black hole or traveling at asymptotic speed.
Then there cannot be a “present” occurring at the same time for the whole universe as Newtonian physics once admitted.
In quantum physics, time is even something that doesn’t need to exist. All the basic equations that describe the quantum world need not have a time variable to be correct. So maybe there are places, in the microcosm, where time really doesn’t exist?
What if one day physicists discovered the meaninglessness of time. And all of our lives are just drifting in an endless loop, instead of having a beginning and an end as we once thought?
Starting from a crisis in physics
Physics is in crisis. That is the reality that we must face more than a century later, when scientists have explained the universe with two extremely successful physical theories. The first is general relativity and the second is quantum mechanics.
Quantum mechanics describes how things work below the microscopic world of extremely tiny particles. General relativity, on the other hand, describes the big picture of gravity and how objects move on a cosmic scale.
Both theories work extremely well in their own right. But it is not difficult for us to see that they have contradictions with each other. Although the exact nature of this contradiction is something that physicists themselves have to contend with, in general they have reached a consensus that: Both of these theories should be replaced by a new, more general theory.
This new theory is called “quantum gravity”, a theory that unifies both general relativity and quantum mechanics, allowing to explain everything in the universe as we know it. Quantum gravity also allows us to explain what the two older theories could not, such as how gravity works on the miniature scale of particles.
In the past, there were many physicists who tried to formulate the theory of quantum gravity. The problem is to overcome the contradiction between relativity and quantum theory. The hope of doing this has been given to string theory, in which particles are replaced by strings vibrating in 11 dimensions.
However, string theory also faces another difficulty. Although they provide a wide range of models that describe exactly how a universe like ours works on a general scale, string theory doesn’t really make any definite predictions. can be tested by experiments to find a suitable model.
That can be seen as a failure of a theory, because in physics, a strong theory needs to do both: Explain the world and make predictions for it, how things will be. how it works.
This is also the reason we have to bow to Einstein’s theory of relativity, when he predicted the existence of gravitational waves 100 years before humanity actually found and measured them in the universe. With string theory, scientists simply cannot predict anything with it.
So by the 1980s and 1990s, many physicists became dissatisfied with string theory. They have come up with a series of new mathematical approaches to try to build the theory of quantum gravity.
One of the most prominent of these models introduces a phenomenon known as “loops” into quantum gravity. These loops interpret the fabric of both space and time as an infinitesimally small network of discrete components with no beginning and no end. This seems to have completely removed time from quantum gravity.
Does time disappear? And if so, what will happen?
Not only quantum gravity, a number of other physical theories that scientists are building can also eliminate the need for time. So now we understand that physicists are finding new theories that explain and predict the universe. And these theories can exist independently of the variable t.
Now, assuming such a theory is proven true, would it make our time disappear?
The answer is quite complicated, and it turns out, it depends on and determines the meaning of our existence.
We know physical theories do not include the appearance of any table, chair or person, yet we still accept that tables, chairs and people exist.
Why? Because we assume that such things exist at a higher level than the one described by physical theory. The existence of this table, this chair and us humans is a combination of billions of tiny particles of matter, atoms, subatomic particles like quarks or electrons…
But while we have a pretty good feeling how a table can be made from elementary particles, we don’t know how time can be “made out of” something elementary. .
So unless we can use a new theory to explain how time came to be, or how it is made up of something smaller, we can’t accept the existence of time. .
On the contrary, to say that time does not exist is like saying that there is no table in the world. Humans can try to live in a world without any tables, but managing in a world without time seems like a disaster.
Our entire lives are now built on time. We plan for the future, based on what we know about the past. We hold people morally accountable for their past actions, with the aim of reprimanding them later.
We believe that we ourselves are an agent (an entity that can do things), we can influence the cause and effect of the universe because part of us can plan our actions in such a way that we want.
But the law of cause and effect can be broken completely, if time does not exist, because what is the point of causation when it is impossible to determine the time when the cause occurs first and the effect occurs later?
Now, can the courts punish a criminal for what he has done in the past? When the past doesn’t exist, and his will doesn’t really dictate his criminal actions?
The discovery that time does not exist would seem to bring the entire world to a halt. We will have no reason to get out of bed in the morning, when the alarm goes off.
So we have to hope that, at least, if there is a theory of physics that excludes the existence of time, it must somehow still be causal. That is, human consciousness must be an agent that makes a difference.
Such a theory would tell us that physics is actually causality, not time. Causality is the fundamental feature of the universe. Only when that is true can the world and society as we know it continue to exist.
If we don’t, we simply fall into a mess, in the same way that the whole planet is blasted out into space, when the gravitational force that Newton discovered is no longer available.
Refer to Theconversation