The source of time cannot be found. There is no point in worrying about it

Time can fly. I noticed this when I moved in the last few weeks. Another day passed, and so many boxes to wrap!

I would have preferred to see the time pass on a trip to mountain huts in the French Alps or somewhere by the sea. On the other hand, it is better to fly than to crawl between cardboard boxes and bubble wrap. Not just because I’m fed up with those boxes, but mostly because it’s often a bad sign when events unfold like in a slow-motion movie – crawling through time doesn’t always bring anything good.

It is of course psychology, the feeling that time freezes or just passes. Like struggling not to lose, wasting or wasting time or twisting to gain or stretch time. Time itself flows inexorably and indifferently.

Has she always done that? It had been the idea for a long time. The image of the universe was that of a vast static and unchanging backdrop against which a world clock beat time. As the famous naturalist Isaac Newton says in his 1687 book Mathematical Principles of Natural Philosophy defined: “Absolute space remains, of itself, independent of any external influence, always constant and motionless” and “absolute, true and mathematical time proceeds from itself and from itself uniformly independent of any external influence “.

This means that space and time are also fundamentally different from each other: space is and remains and you can go back and forth in it, but time travel is impossible. And unlike “here”, “now” is gone as soon as you say the word: time is elusive. Or as Church Father Augustine wrote at the end of the 4th century: “So what time is it? When no one asks me, I know; but if I want to explain it to someone who asks, I don’t know.

Thread without beginning or end?

What works is measuring durations – of a life, of a movement, or of any change in the cosmos. Astronomers and other naturalists have been doing this for millennia. Each orbit of the earth around the sun lasts for one year, the movement of the moon is related to the months and the rotation of the earth on its axis defines the day which can then be divided into hours, minutes and seconds. Today, the periodic movements – which repeat themselves continually – of vibrating atoms in an atomic clock record this second with extreme precision. The duration of all of these repetitive movements is the measure against which to measure the duration of all other changes and movements.

Such measurements of time would be impossible in a universe where nothing ever happens. Such a universe must be timeless. In the words of this same Augustine: “If nothing passed, there would be no past, if nothing to come, there would be no future, if nothing, there would be no present. But even if in a cosmos all movements and events were chaotic, random, and crisscrossing, you couldn’t talk about time as we know it. If you think about it this way, time is a measure of the very changes that are the product – in principle predictable – of cause and effect.

The matter is arranged in galaxies which move away more and more like currants in a paste which goes up

Concretely, this means that with Newton’s laws you can – in principle – predict very precisely when a board will fall apart to the ground and how much it will fall out of your hands when packing. The direction of time is determined by the physical concept of “entropy”, which can be loosely seen as nature’s neglect and which renders processes such as the rupture of a plaque irreversible. Time itself then irrevocably links in such formulas all the successive states derived from one another, from the fall to the crushing of the board. And so, like a kind of thread, physicists always see time – even though Einstein made them think of time differently. So the question in this series is: is this thread in a circle, is this thread infinite, or does this thread have an end and a beginning?

The short answer is: we don’t know. Physicists, cosmologists, and astronomers only know – for sure – that the universe itself had a beginning. Their “big bang model” is one of the greatest achievements of the natural sciences of the twentieth century. It was born out of Einstein’s new way of thinking about clocks and time over a century ago. Because light is the fastest way to transfer information, and because the speed of light is finite, there is no “shared now,” Einstein showed. If I blink “now” someone in front of me sees that blink a fraction of a second later – and the farther away they are, the longer the delay, of course.

Likewise, the finite speed of light drives out the world clock in the cosmos, and all points in space have their own clock. In Einstein’s theory, space and time together form a dynamic spatiotemporal fabric in which heavy masses such as stars or black holes sink: they stretch space locally and locally slow down clocks. And with countless observations and measurements, this concept of expandable space-time led to the idea a century ago that the universe itself is dynamic and expandable. In other words, 13.8 billion years ago, energy, matter and space-time emerged from a starting point: this Big Bang. And that matter has since arranged into galaxies that drift apart more and more like currants in a raisin bread dough that rises as space expands.

Singularity

But if and how did “time” begin to run during this big bang 13.8 billion years ago? The first moments of the cosmos are literally shrouded in haze: a glowing haze of charged particles – the building blocks of all subsequent matter – has absorbed all light and made the universe opaque. And while circumstantial evidence and theoretical predictions may lift a corner of this veil, they fail to comprehend the very first moments. They are just as inaccessible as the memories of the first moments saved from a life beyond language. The language of mathematics, of the theory of relativity and of quantum mechanics, can only be used from a later time, “in the beginning”, when something already existed. The big bang itself is a singularity: a borderline case about which no assertion can be made.

Seems best not to worry too much about the nature of time, eternity, and nothing

If intrepid scientists talk about what may have happened when, during or even before our universe began to run “our time”, it is mostly joyous speculation. For example, was the starting point of the universe as we know it a point between several points and did it explode like a super bubble by an accidental “quantum fluctuation”? Have other such “bubbles” been blown and is “our” universe part of a vast array of (potential) universes somewhere in more than three-dimensional space, as string theory suggests? ? Is it a link in a chain of universes which expand, then contract, then disintegrate, after which a new universe rebounds, as the mathematical physicist Roger Penrose assumes? Or did it emerge like the bulge of another universe, then cut like a drop in a lava lamp – a scenario physicist Sean Carroll suggested?

Five centuries ago, Erasmus laughed at his In praise of madness already with the contrast between what humans are capable of and what the universe is: “They [de natuurfilosofen] build countless worlds by measuring the sun, moon, stars, orbits of planets with a ruler or tape measure, […] as if they had been the secretary of nature itself, the architect of all things, and as if they had come to us from the assembly of gods. And despite the success of the big bang model, it is still impossible to really understand the universe and time: from Earth we cannot see until, let alone beyond, the big bang. And the radius of the “visible” universe is limited by the distance that light has been able to travel in 13.8 billion years. What lies further or further behind remains obscure.

Brain like galaxy

So it seems especially best not to worry too much about the nature of time, eternity, and nothing, and whether the two might be the same. At best, thinking about it helps put things like moving boxes and bubble wrap into perspective. At worst, it will drive you crazy. Either way, you end up with a sense of helplessness and insignificance: what is life like compared to 13.8 billion years ago and everything we can’t know at -of the ?

At the same time, the same science that offers such intimidating facts and with which Erasmus somewhat laughed at him can also give courage. In his recently published book Fundamentals calculated the Nobel Prize winner and theoretical physicist Frank Wilczek for the duration of a (conscious) thought and the number of thoughts people can have in their lifetime. It will vary from person to person, but Wilczek’s estimate was approaching a billion. It would also include some 100 billion visual impressions – and that number approaches the number of stars in our Milky Way galaxy. In other words, a person’s life may be less than a fiber in a “temporal thread” of 13.8 billion years, but in everyone’s head, and without even being able to ‘Identify its exact start, a Milky Way galaxy is unfolding. impressions – a universe in itself.

Vector Illustrations Jasmin van der weide