Can there be a universe without light?

Before the big bang : How can the universe arise from nothing?

Nothing comes from nothing, they say. But maybe that's not true at all. In the view of modern physics, what was previously unthinkable is apparently possible: things arise out of nowhere without the intervention of a Creator. Even the universe could have been created in this ghostly way, some scientists believe. The cause for this are quanta, the tiniest energetic particles. So you were at the beginning of a creation out of nothing.

Lawrence Krauss is one of the physicists who think this is plausible. In his book "A Universe Out of Nothing", the researcher from the State University of Arizona argues with quantum gravity. This is an unfinished building of ideas in which quantum mechanics - the physics of the smallest particles - and the theory of relativity, which describes the structure of the universe on a large scale, are united. Wherever quantum gravity prevails, universes can, indeed must, arise from nothing, claims Krauss. Even if they are only remotely similar to our “home cosmos”.

Even the best vacuum is not empty

The nothing of Lawrence Krauss has it all. Because from the point of view of quantum mechanics, there is actually no such thing as empty space. According to Krauss, even a perfect vacuum contains a “boiling brew of virtual particles that appear and then disappear, but so quickly that we cannot see them directly”. Physicists call such random energy fluctuations in a vacuum quantum fluctuations. You understand it to be the spontaneous emergence of a particle and its counterpart, an antiparticle. Usually they cancel each other out again shortly afterwards, so that the law of conservation of energy is preserved. Because there is no energy out of nowhere.

But it is conceivable that at the beginning of the (or one) universe there was a tiny unequal distribution, a slight excess of matter over antimatter. In this case, they would not immediately annihilate each other, but a little more matter would remain. "That would lead to all the substance that makes up those stars and galaxies as we see them in the universe today," writes Krauss in "A Universe Made of Nothing".

Krauss' theory provokes contradiction

What could be considered a small achievement in itself, a small asymmetry in the early days of space, could be seen as a moment of creation. Even if it affected just one particle in a billion, that would be enough to create as much matter as we see in the universe today.

So much for the hypothesis of the origin of the universe as represented by Krauss and others. Too much ado about nothing, however, found the philosopher David Albert of New York's Columbia University. In the "New York Times" he tore up Krauss ’book. Albert's central argument: The nothing claimed by the physicist is actually something that already exists, consisting of "relativistic quantum fields". These fields are the origin of matter, and occasionally a vacuum state in which they contain no matter.

The nothing in the Bible is nothing, says the physicist

Vacuum states are special combinations of elementary physical arrangements, says Albert. Just like giraffes, refrigerators and entire solar systems. Only the absence of quantum fields would be true nothing. The fact that from time to time particles appear and then disappear again because the fields are rearranged is not surprising. No trace of a creation out of nowhere!

Of course, many questions are still open, countered the angry Krauss. "We don't know how something can come out of nowhere, but we do know some plausible ways how it could happen," said the physicist in an interview with The Atlantic magazine. “Empty space as I describe it is not necessarily nothing, but it was more than good enough for Augustine and the authors of the Bible. For them, eternal empty space was the definition of nothing. I can prove that this kind of nothing is no longer nothing. "

Space and time lose their contours

Krauss goes one step further. Today's knowledge of quantum gravity even makes it possible to understand the creation of space in a place where none was before. Physicists like Stephen Hawking at Cambridge University have carefully approximated quantum mechanics and relativity. They found that the same applies to space as to energy and matter, if one applies the smallest conceivable scale. Under the conditions of quantum theory it too loses its stability. Space and time do not remain smooth and continuous, but are transformed into a foam of space-time bubbles.

Space-time bubbles can form spontaneously. "If you 'quantize' space and time, they fluctuate," says Krauss. “You can create virtual space-time just like virtual particles.” Then we are faced with a situation in which there is no matter in space - and not even space, the physicist argues. "That is much closer to nothing."

No space, no time, no matter. More, better: less, is hardly possible. A quantum-sized space bubble could have been the seed of the universe and expanded rapidly during the Big Bang, believe theorists like Alan Guth of the Massachusetts Institute of Technology.

There is a fine line between challenging theories and pure fantasy

Such hypothetical considerations far exceed our everyday understanding of space, time and material things. And they also arouse skepticism and opposition in specialist circles. "If space and time themselves arise from a quantum fluctuation, then what they arise from can be given the name 'nothing'", says Hermann Nicolai, theoretical physicist at the Max Planck Institute for Gravitational Physics in Potsdam. "Such ideas are appealing, but one should be careful not to speculate too much." Krauss and Hawking worked with "thought mathematics," says Nicolai. The mathematical expressions they use may be pointless and should be used with caution.

Not only Nicolai is cautious. Physicists are debating how useful thought games are, in which universes arise like gas bubbles in a simmering saucepan, sprout on a time tree that branches off into yesterday, or owe themselves to the vibrations of the tiniest strings of a 26-dimensional cosmic orchestra. The nasty word "fantasy" is used. But it's a fairy tale world full of math.

“Nothing is inconsistent,” says Krauss, and this assertion is at least experimentally confirmed. Quantum fluctuations are measurable, their meaning in the creation of space appears plausible. As a materialist, Krauss believes that with this move he has made a creative authority outside of physical events superfluous. This cosmic theater can do without a director. Even more: In this reading, nothing has a productive, positive meaning. It is the reason for all being, a fertile field.

Nothing has a bad reputation in intellectual history

This rehabilitates a bad boy in intellectual history. Because nothing has a bad reputation in the West. It “does not”, as the philosopher Martin Heidegger stated, who linked it to the feeling of fear. Even ancient Greek philosophers, especially Aristotle, were of the opinion that nature "shrinks back" from nothing. There is therefore no real vacuum. Aristotle argued against empty space with thought experiments. The four elements fire, air, water and earth lose their natural direction in the void. Orientation and measurement would not be possible in it, bodies would fall infinitely quickly. In short: the cosmos would be out of joint if a cavity was allowed.

In order to counter the threatening emptiness, Aristotle introduced a fifth element, the ether. This heavenly substance, in the Middle Ages quinta essentia (Quintessence) called, filled the heavenly spheres as a pure and transparent entity. The Horror vacui the philosopher shaped the West well into modern times.

According to Christian teaching, God created the world out of nothing. For the Church Father Augustine, this doctrine was the starting point for worrying considerations in the fourth century. Unlike the Greeks, Augustine granted nothing a certain right to exist. After all, the universe had been created from him. However, Augustine also saw the void as a negative counterpoint to the world. For him nothing was an expression of evil, meant death and perdition.

With spiritual energy against the blackout

Because people, like the whole of the universe, come from the void, this is part of their heritage. It manifests itself in a natural tendency towards the dark, believed Augustine. If God did not save his creatures from the abyss of emptiness, they would immediately fall back down into the gullet from which they once emerged.

One gets the impression that God has to constantly fight against nothing and constantly generate spiritual energy against the blackout. "The universe would disappear instantly if God were to lift up His protective hand," says Augustine.

It was a German politician who took the horror of emptiness away. Otto von Guericke, Mayor of Magdeburg, created a vacuum in two hemispheres pressed together with the help of an air pump in 1657. Even eight horses pulling in opposite directions could not force the bullets apart. So there was it, empty space. And what power there was in him!

Guericke attributed a powerful role to the vacuum in the game of the worlds

Mayor Guericke raved about an infinite universe in which the vacuum played an “active and powerful role”, as the science historian Helge Kragh from Aarhus University writes. For Guericke the void was full of heavenly glory, higher than the stars, brighter than lightning and perfection itself. Divine, yes God himself.

Does nature abhor emptiness? Aristotle seemed refuted by Guericke. But the scientific debate about the ether and nothing did not end there. Naturalists from Isaac Newton to James Clerk Maxwell were followers of the invisible and all-pervading substance. How else should light or magnetism propagate? In the 19th century, the ether was booming more than ever, and theories about the magical essence sprang into action. Space without ether is like a forest without trees, argued the German physicist August Föppl.

With Einstein the "ether" became superfluous - now it is returning

It was only with Einstein's theory of relativity at the beginning of the 20th century that the assumption of an ethereal medium between the worlds became obsolete. Physics got by without the ether, it had simply become superfluous. The current discussion shows, however, that the aether of yore has risen again under different auspices.

The vacuum of space, filled with virtual particles as a new ether, has become the starting point for fundamental reflections on the cosmos. Perhaps this “quantum vacuum” is the source of the “dark energy”. It is apparently so powerful that it is able to drive the universe apart ever faster.

"The fate of the universe, it seems, is decided by the properties of the vacuum," says physicist Paul Davies of the State University of Arizona. Whether the event ends in a cosmos of dark emptiness, in which matter and energy are infinitely diluted, or furiously in a “big crunch”, in which the universe collapses, depends on the quantum vacuum. The great struggle between abundance and emptiness has not yet been decided. But it is possible that both are dependent on each other. Just as becoming and passing go together.

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