Machine Translated by Google Machine Translated by Google Machine Translated by Google © Westend Verlag GmbH, Frankfurt / Main 2023 The work, including all its parts, is protected by copyright. Any use without the consent of the publisher is prohibited. ISBN: 978-3-86489-881-5 Cover design: Buchgut, Berlin www.westendverlag.de This applies in particular to reproductions, translations, microfilming and storage and processing in electronic systems. The German National Library lists this publication in the German National Bibliography; detailed bibliographic data are available on the Internet at http:// dnb.d- nb.de available. More about our authors and books: Design and typesetting: quintessense, Berlin Machine Translated by Google The space- time The forces of nature The world view of physics: What is a universe and how did ours come into being? Chapter 3 Civilization in the Dark Cloud The elementary particles Chapter 2 Chapter 1 The Laws of Nature Chapter 4 foreword Contents Inflation, the horizon problem and flatness Open Questions in Physics Dark energy What was before the Big Bang? dark matter Hawking radiation Four answers to the "why" question antimatter How did the universe come into being? Black mini holes The tailor- made universe The Natural Constants The 18 free parameters of the Standard Model foray into the unknown The Higgs particle gamma- ray bursts A Quantum Theory of Gravitation gravitational waves Machine Translated by Google list of figures Conclusion: What does all this mean? Inexplicable, Incomprehensible and Uncanny quantum physics Chapter 5 information Machine Translated by Google Century, the world has been largely explored and the remaining questions will probably be answered in the foreseeable future. But as I delved deeper into the theoretical framework of physics, whose insights are considered to be among the most fundamental, and my view expanded more and more, I began to doubt the completeness of its world view. Physics has developed a model of reality that initially looks convincing, but on closer inspection has holes and ambiguities. There are also "patches" based on unprovable assumptions that are used to simply "repair" inconsistencies in the large models ad hoc. One example is the inflation theory. The universe is said to have expanded at superluminal speeds for a brief moment immediately after the Big Bang. There are hypotheses about the background to this claim, but no experimental evidence. The assumption is merely a patch on the Big Bang model that is necessary to solve the so- called horizon problem. I explain this in more detail in the book. Without it, there would be serious doubts about the validity of the theory. But the Big Bang model has the problem that it cannot explain the Big Bang. Is a theory still appropriate if it fails to explain the object it is named after? There are many other ambiguities and puzzles of this kind. In the last two chapters of the book we deal with scientific findings beyond human understanding. At the beginning of my career, like many others, I believed that science in the 21st century would be a challenge. This book is the essence of the last ten years of lectures that I have given in the physics master's program at the University of Konstanz. Our small department has specialized in nanoscience in research, but in teaching it is necessary to cover all sub- areas of physics. So it happened that, as an expert in the field of nanoparticles, I unexpectedly had the opportunity to give events on topics outside my actual field. These included the lectures "Astrophysics" and "Limits of Knowledge", in which I took the students to the edge of our understanding of physics and biology. My original training is that of a nuclear physicist, which is why I also taught "nuclear and particle physics" more often. My core competencies also include the "nano lecture" and the "basic course in quantum mechanics". All of these events are not individual lectures, but lectures over an entire semester, with 20 to 40 hours of speaking time per topic. Some of them, especially from the time of the pandemic, are on my YouTube channel “Limits of Knowledge” and on my website “www.grenzen- des- wissens.com” freely accessible. However, I would like to say right away that in this book we will approach the material much more gently, work with examples where possible and occasionally repeat complicated points to avoid unnecessary leafing through. What is that supposed to be? In a figurative sense, information could be equated with "mind". "Excuse me?" I can already hear people shouting: "Mind as the basis of all existence? That sounds extremely unscientific!" - and yet there are serious people in academic physics who support exactly this thesis. Their slogan is "It from Bit". That means that all existence arises from information. I also found that quite exotic at first. But the more I learned about physics, the more thoughtful I became. This thoughtfulness manifests itself in this book. As a side effect, I bring the magic back into our world. It is possible that our consciousness cannot fully grasp the reality of these zones, which lie far outside our everyday reality. This includes, for example, the view held by some physicists that the basis of all existence is not matter, but "information". foreword Machine Translated by Google Machine Translated by Google This book is about reality - what we know, what we only think we know, and what we don't know. It is a book that questions physics' claim to be able to explain everything. It is based strictly on the findings of scientific experiments. This refers to the results of measurements, i.e. surveys of reality, that have been published in established scientific journals. It will become clear that some of these experiments can hardly be reconciled with the models of physics. Civilization in the Dark Cloud 1 So it is by no means true that we have already discovered everything fundamental and are only working on refining our previous findings. On the contrary, there are even indications that we will make great discoveries in the future that go far beyond established physics. This book is about them. It takes the reader into spaces and times far beyond the four- dimensional space sphere to which we think we are limited, and into intellectual spheres in which the world does not consist merely of balls and springs whose vibrations slowly die away and drift towards freezing death. Instead, it shows, for example, the possibility of an information- based, "intelligent" universe whose elementary particles are bits of a huge computer. The basis of natural science is the agreement between theory and experiment. If a physical model is so in line with the current zeitgeist, there is a chance that it will simply ignore observations that do not fit. But reality is alien. Perhaps the human mind simply does not have the capacity to grasp it in its entirety. In that case, only a small part of reality would be accessible to our thinking. We can hope that it will slowly increase over the course of the centuries. There are many mathematical formulas, but only a few correspond to reality. The correspondence must first be tested in experiments. And only if a theory passes this test does it attain a certain degree of truth. Because then it describes at least parts of reality correctly. Even in this book, which is committed to natural science, experimental proof must always be provided that confirms the claim that there is more than what physics has discovered so far. However, it is not possible to describe the unknown, because then it would be known. We must therefore limit ourselves to showing evidence for the existence of such areas of reality. Of course, there are plenty of them, which is why only the most important ones are described in the following chapters. These pieces of evidence are mostly open questions and inconsistencies in the established world view of physics. They could be viewed as insignificant. In its basic features, the phenomenon is not new: in the past, too, there was always a danger that the currently prevailing worldview would distort the models of natural science, as was the case in the times when people were still convinced that the earth was flat and the center of the universe. Ironically, the more recent findings of natural science have since then led to their absolutization again. In the current conception, life and consciousness are only extremely improbable coincidences, errors in the automatic operation of a machine universe. The world has lost its magic. Currently, the world view of physics is strictly materialistic. Accordingly, the universe resembles a gigantic machine whose gears in the form of natural laws control the course of certain processes. In physics, neither mind nor sense nor consciousness exist - and not even life. This world view represents a zeitgeist that has turned away from the idea of the "supernatural" and wants to analyze everything from a machine perspective. And that means that there are gaps in our ideas about reality. There is more than we can imagine. Machine Translated by Google Once upon a time, there was a civilization in a dark cloud. These collections of finely distributed cosmic dust, which at least over long distances does not allow light to pass through, are found all over our galaxy. We know from infrared images taken by space- based telescopes that they also contain suns. Their winds probably clear the immediate area around them of dust, so that these stars form small islands in a sea of darkness. Three planets orbit our imaginary sun: an extremely hot rocky planet near the center, similar to our Mercury; a red gas giant on the outside edge, similar to our Jupiter; and finally a blue water planet that orbits at just the right distance from the sun in the dust- free bubble. Let us assume that the conditions on this planet are as favorable for life as on our Earth. This is how life comes about and goes through similar stages of development to those we know from here. The laws of nature are – as far as we know today – the same everywhere in the universe, which is why such a course of events is at least not impossible. This applies to the sphere of space accessible to us with a diameter of 13.7 billion light years, and certainly also within our galaxy, which is only a few hundred thousand light years wide. Our imaginary planet first formed as a glowing lava ball that gradually cooled down. Then it rained for tens of thousands of years and the oceans formed. Simple, single- cell life developed in them. It stayed that way for two or three billion years. Over time, photosynthesis added more and more oxygen to the planet's atmosphere. This accelerated evolution enormously. Life conquered the continents because it was protected from UV radiation by the ozone layer newly formed from the oxygen. Land plants and animals reached ever higher levels of development until intelligent life finally entered the scene. small details that will probably be clarified over time without us having to fundamentally change our view of the world. But the following fable perhaps illustrates that open questions and disagreements can indicate a limited view: What it looked like exactly is not relevant to our fable. What is important is that it used tools, built machines and thought about what kind of world it lived in and how its home in the cosmos might have come into being. Machine Translated by Google They had discovered the quarks and the four forces of nature. But although they were able to describe the fusion processes inside their sun mathematically, they had no idea how it could have been created. They examined the surrounding space, but only saw the enormous amounts of cosmic dust that stretched into seemingly endless distances. Probes penetrated many billions of kilometers into the dark cloud, but always found nothing but darkness. The researchers could not have known that it was only a dark cloud - itself just a tiny part of the larger galactic structure - in which they were. From their perspective, the entire universe seemed to consist of dust. But where did it come from and why was there a sun with three planets in it? Their physicists thought about it for a long time and finally developed the “primordial hole theory”. According to this theory, an unimaginably long time ago – rough estimates based on the amount of dust suggest at least 10,000 billion years – a hole spontaneously appeared in space- time. A constant flow of hydrogen atoms penetrated through this hole into the normal space- time continuum. A constantly swelling gas bubble formed around the hole, which was held together by its own gravity. The latter increased with increasing mass. Scientists there discovered the diverse laws of nature, similar to those on Earth, and developed sophisticated biology, chemistry and physics. They knew that matter is made up of atoms, which in turn consist of elementary particles. Up to this point, everything had happened exactly as it did on our Earth, with just one important difference: the intelligent beings knew nothing about other suns, other galaxies and the cosmic background radiation, the afterglow of the Big Bang. Their knowledge of the universe was severely limited by their existence in a cosmic dark cloud. Fig. 1: Illustration of the imagined civilization in a dark cosmic cloud. In the middle is the solar system with the three planets. The intelligent inhabitants of the second star have no knowledge of other suns or galaxies, unless they develop interstellar space travel and manage to venture into open space. They would certainly be very surprised by the sight. Machine Translated by Google –, which are not covered by merger processes in the which catalyzes the formation of these heavier elements. But the sceptics had even more questions and the defenders of the primordial hole theory gradually became annoyed. How did the primordial hole come into being and what was there before it? This hit a sore spot: the theory had the weakness that it could not explain the primordial hole itself. Its supporters responded in an irritated tone that there had been no matter in the universe before the primordial hole came into being and that every point in time had been identical to the previous one. Their questions are therefore contradictory and therefore not permissible. The proponents supported their theory with countless observations and were able to explain many previously puzzling data. Nevertheless, there were sceptics. They asked, for example, how it could be that exactly the right amount of hydrogen had flowed out of the primordial hole in a constant flow over billions of years. The proponents had an explanation ready for this, based on a theory about singularities in the four- dimensional space- time structure, which no one else understood except themselves. In any case, they were certain that the known laws of nature did not contradict the phenomenon of a constant inflow. The sceptics remained suspicious, but could not object to this because the mathematics of the primordial hole theory was far beyond their capabilities. In addition, there was no chance of experimental verification. Theories of this kind are among the models of physics that cannot be falsified - unless an artificial primordial hole had been created in the laboratory or a probe had been sent to the center of the sun. However, neither of these was technically possible. Some skeptics even said that a non- falsifiable theory was not real science. But the researchers in the dark cloud didn't know what else to do. –, There was another question from the skeptics: Where do the many chemical elements come from - all of those that are heavier than iron - that could have been created in the sun? The primordial hole theorists replied somewhat sheepishly that they had no definite explanation for this at the moment, only a theory. According to this theory, there was an as yet unknown type of matter - they called it "bright matter" because it must be present in the center of the sun in a bright white glow. From then on, much research was carried out on this mysterious substance, but it persistently evaded every attempt at experimental proof. continued to grow until the structure finally contracted and the hydrogen atoms in its center began to fuse together. Fiat Lux - and thus their sun was born. With the constant influx of fresh fusion fuel through the primordial hole, their star burned for thousands of billions of years. The large amount of dust in the observable universe - or so the theory goes - is simply a byproduct of the sun, carried far into space by its winds. The composition of the samples collected also matched well with the known fusion processes that should take place under the conditions in the center of their star. The sceptics were initially baffled by this response and later suspected it was an excuse. In any case, their questions remained unanswered and no answers were offered. Machine Translated by Google Afterwards, in chapter 4, we finally enter the world of the unknown. We can only speculate about this sphere. Although our assumptions are based on the results of verifiable experiments, their data and findings are beyond human understanding. It is about the possible existence of higher dimensions and other universes. For a long time, mankind was convinced that there was only one planet, namely the Earth. After this turned out to be wrong, people believed from then on that there was only one sun. With the discovery that the many bright spots in the sky were also suns, people corrected their world view and now thought that there was only one galaxy, rotating alone in the center of the universe. But that was also wrong, because we now know that there are countless galaxies. We currently believe that the Big Bang only produced one universe - ours. You might think that people will never learn. So we start in Chapter 2 with the current world view of physics. This is the representation of reality that the discipline has developed so carefully to date and whose correctness no one really doubts anymore. But even in the dark cloud there was widespread agreement that the ur- hole theory can successfully explain numerous observations. In Chapter 3 we then venture our first steps into a frontier area of physics, to the limits of our knowledge, so to speak, and even a little beyond. The journey brings us into contact with phenomena that science cannot yet explain, but which, as science itself believes, will probably be able to explain in the medium term within the framework of known theories. After we have discussed in Chapter 4 have left the boundaries of knowledge behind us and are already deep in the zone This is not to say that there was no Big Bang in our reality. On the contrary, we will see in the next chapter that we have a lot of experimental evidence for the correctness of the underlying theory. But there is still a certain doubt that perhaps this is not the last word on the question of how our world came into being. Doubts would have been rejected there too. The chapter is relatively long because we cover the entire history of physics in it, at least in broad outline. Because if you want to have well- founded doubts about the validity of its world view, you should be familiar with its most important statements and theories. In fact, such theories could even be simply wrong. For example, there is the question from the fable of why exactly the right amount of gas comes out of the primordial hole to keep the sun burning for so long. With our far more comprehensive knowledge of the universe, we of course know that primordial holes do not exist and therefore the whole approach is wrong. But even in our worldview we are confronted with questions that cannot be answered. For example, if certain natural constants had a slightly different value, the properties of our universe would be so shifted that no life in our sense would be possible. So why is our universe "tailor- made" for us in such a strange way? Furthermore, in the fairy tale there is "light matter", an allusion to dark matter and dark energy in our real world. Our physics must also assume this as fiction without experimental proof in order to be able to explain certain phenomena. Finally, there was the question of how the primordial hole itself came into being, for which the theorists from the fable had no explanation. Their argument that there was no time before and therefore the question is not valid is similar to that of some actual physicists when asked about the universe before the Big Bang. This short story is intended to illustrate that open questions and inconsistencies are a sign that people only know a part of reality. They are reflected in the models that are developed on the basis of incomplete knowledge. of the unknown, we conclude with Chapter 5 It deals with the role of information in animate and inanimate nature. What is "information" anyway? Does it have physical reality or does it only exist in the human mind? What can it explain? There are theories that do not see matter as the basis of all existence, but information. Their credo is "It from Bit". Our world becomes a gigantic computer. It sounds like a Hollywood fantasy, and yet Machine Translated by Google There are experimental findings that point to the fundamental importance of information in inanimate nature. Finally, it can also be paraphrased as "mind". And this is where things get a little scary. Machine Translated by Google Classic physics lessons begin with mechanics because it is generally considered to be the simplest sub- field. From sixth grade onwards, students therefore first learn Newton's axioms and the laws of force. They then usually move on to the inclined plane and the pendulum. But by then, at the latest, most students have already decided that they would rather choose biology in high school because studying inanimate nature is apparently incredibly boring. This classic way of introducing physics could therefore be described as didactically inept. That is why we are taking a different approach here. The following thought experiment: Let us assume that we had absolute power over reality and decided to create a new universe. What would we need to do this? In other words: what are the components of a universe - according to our current level of knowledge? In fact, you only need five components: space- time, elementary particles, natural forces, natural laws and natural constants. We will devote a separate section to each of them. The world view of physics: What is a universe and how did ours come into being? 2 They determine what the next image should look like. The only difference to film is that, unlike photos, the "images" in reality are three- dimensional rather than two- dimensional. This idea forms the basis of classical physics and prevailed until around 1900. Space is the stage, the balls roll around in it, connected by the springs of the forces of nature, and time is a film made up of individual, consecutive still images. If that were true, however, we would not have free will, since the future could be determined exactly if we only knew the coordinates and speeds of all the atoms at any given point in time. Then the entire history of the universe since the beginning of time would practically run on rails. But that does not correspond to our perception and, as we now know, is not the case. In the imagination of classical physics, space is an empty stage on which small balls in the form of elementary particles move, which in turn are connected to one another via springs, the forces of nature. Time consists of snapshots that follow one another quickly. In each still image, the small balls have moved a little further - just like in a classic celluloid film. Each of these snapshots is connected to the next via the laws of nature. Two components are still missing in our artificial universe to finally determine its properties: the laws of nature and natural constants. In contrast to the decisions of the legislature in parliaments or the matter that the legal profession deals with, the processes in the universe follow rules that are inherently impossible to violate. The laws of nature dictate to the entities on the stage of space- time how they should behave. In our analogy, they would be like a kind of script. After all, the balls could be lighter or heavier, the springs harder or softer and the film could run faster or slower. These details are determined by the natural constants. Once we have these five components together, all we need is instructions on how to build a universe from them. To do this, we take a look into the past. Because our universe also came into being naturally and the Big Bang theory explains exactly how this came about. It therefore deserves its own stop on our journey through modern physics. Machine Translated by Google It was previously believed that a vacuum meant the absence of everything we know. 2.1. Spacetime The idea that our vacuum is anything other than nothingness, the absence of everything known, goes against common sense. It tells us what is reasonable in our familiar environment, for example that clocks run at the same speed and the earth is flat to the horizon. What lies beyond that usually has no effect on our immediate everyday life. Let us assume that there is a new type of track on which trains can reach extremely high speeds. A locomotive pulls a long, flat wagon, similar to a track, on which a cyclist moves in the direction of travel. Under normal conditions, the speed of the cyclist, measured from the platform, would be added to the speed of the train. The cyclist would therefore be travelling a little faster than the locomotive, at least until he reaches the front of the wagon. Now our fictitious train accelerates more and more and approaches the speed of light. If the above rule that the speeds add up applied, the cyclist would eventually be faster than light. That is There have been four revolutions in our conception of what space and time are. We were like a fish that doesn't know what water is because it doesn't know the state of "no water". For it, the absence of everything known - other fish, jellyfish, plankton, grains of sand and dirt particles - would be a "vacuum" - but for us from the outside, it would just be clean, clear water. However, a particularly attentive fish might notice that its "vacuum" has a temperature and exerts pressure. It might also notice from the resistance when it swims quickly that it must have mass. It might also notice that its vacuum is moving because there are currents. So if our fish were very thoughtful, it would start to ponder how a "nothing" could have temperature, pressure, mass and currents. Of course, we know that water is a substance with all of these properties and feel superior to the fish. But what if our vacuum - the supposed "real vacuum" - also had temperature, pressure, resistance and currents? According to recent findings in physics, this is the case, but we find it just as difficult as a fish in water to recognize the substance behind it. To do this, we would need the experience of "no vacuum," but to achieve it, we would have to leave our universe. But that doesn't seem possible, because supposedly there is only one. According to this, such a situation would arise if we removed all atoms from a volume, especially air. But this idea had to be revised several times during the 20th century. The fact that space and time are something different from what classical physics assumes only becomes apparent under conditions that do not occur in our everyday environment. An example would be the special theory of relativity, the effects of which only become tangible when an object slowly approaches the speed of light. These phenomena led to the first revolution in our concept of space and time. But common sense doesn't help us much if we want to reach the limits of knowledge and beyond, because our very own way of thinking is a child of classical physics - and is therefore around 120 years out of date. If you dig a little deeper, our everyday sense is based on a mental model of reality that has evolved over thousands of years. We can imagine lying on a beach, driving a car or climbing a mountain. We are even able to visualize the cold air on a mountain peak or the feeling of making a snowball. A virtual reality exists in our heads that obeys exactly the same physical laws that apply in our normal world. In everyday life, the assumption that the earth is flat is completely sufficient, because at the short distances that we usually have to deal with as pedestrians and cyclists, it actually behaves like a disc. Common sense, based on thousands of years of experience, therefore has great difficulty accepting that it is actually a sphere. We only really understand this when we leave our traditional habitat, at least figuratively, and look at the Earth from outside, from space. Machine Translated by Google Fig. 2: A cyclist moving in the direction of the locomotive on a long, flat wagon would be faster than light if the train reached the speed of light. But that is not possible in our universe and so time passes more and more slowly in the accelerating train when viewed from the outside. It becomes relative because for the cyclist it still passes normally. In contrast, his universe is enormously compressed in the direction of travel. So there is a maximum speed in our universe, our "vacuum". If you approach it, space and time are distorted. This makes it clear that these two quantities are not different things, but are somehow connected. Time also does not just play the role of a stubborn clock, because it passes at different speeds depending on how fast you are moving. The fact that there is a maximum speed could alternatively be interpreted as the fact that space- time resists excessively fast movements. This is our first indication that it is not simply an empty stage. This all has a fascinating consequence. When astronauts set off for an alien solar system in a very fast rocket, the distance becomes shorter and shorter the faster they fly. –, However, this is not possible – at least not in our universe. Instead, something very strange happens: the cyclist – again viewed from the platform – appears to be moving more and more slowly. He moves in slow motion until he finally freezes. In his own perception, however, he does not stop; he continues pedalling briskly, even when the train has almost reached the speed of light. But if he looks around, he will notice that the universe suddenly looks very strange. It has shrunk in the direction the train is moving. At night, the stars that were previously far away would suddenly be very close. The universe has contracted in the direction of movement. In contrast, viewed from the platform, time in the train almost stands still. In physics, these two strange phenomena are called time dilation and length contraction. Their joint occurrence illustrates the close connection between the things we call "space" and "time". Einstein spoke of a “four- dimensional jelly” – length, width and depth in space are the first three and time is the fourth dimension because both can be compressed and stretched. So we can conclude: Space and time are something different than what our common sense suggests. But that is not all. Einstein revolutionized our concept of space and time for a second time with his answer to the question of what gravity actually is: space- time is curved by mass. An object that you let go of out in space would, if you were careful enough, remain floating in one place for all eternity due to weightlessness. But on the surface of the earth it falls at a steadily increasing speed towards the center of the earth until it hits an obstacle, such as the ground. But what is "pulling" on the falling object? What is accelerating it? Are they tiny particles that we have not yet discovered? Or ghostly threads of an invisible force field? What is a "field" anyway? As part of his theory of gravitation, Einstein came up with the idea that space itself in the vicinity of a Their destination is practically coming towards them. From the Earth's perspective, time in the rocket hardly moves forward. The astronauts only need a few weeks or months to travel distances of many light years. From the Earth's perspective, this is because time passes more slowly in the rocket due to dilation; from the astronauts' perspective, this is because the solar system is practically flying towards them due to length contraction. When the rocket returns to Earth, hardly any time has passed for its occupants. For the inhabitants of Earth, however, they have been on the road for many years. The astronauts have practically not aged. Machine Translated by Google Fig. 3: When a mass such as the Earth is close by, space- time is compressed like a rubber mass. Time passes more slowly and space contracts. If the mass is very large, such as in a black hole, time even stands still. In fact, objects are not drawn into or deflected by gravitational fields, but it only appears that way to us. The light rays that are bent near a large mass such as the sun or a black hole "actually" fly straight ahead, because by their nature they must always travel in a straight line. At least that was Einstein's idea. If their trajectory appears curved to us from the outside, it is because space- time is curved near these large masses. We have no sense organ for space and time because, as living beings, we are anchored in them. Similar to high speeds, space is compressed and time slows down in the vicinity of masses. In weak gravitational fields, such as those on Earth, time dilation is the main effect of space curvature. Masses and even rays of light are seemingly drawn into zones where time passes more slowly. An example from our everyday life may be helpful here: If the wheels of a vehicle rotate more slowly on one side than on the other, its roadway describes a curve. It is curved in the direction of the slower rotating wheels. Like most everyday comparisons, the example is of course flawed, but at least it illustrates the relevant connection between space (in the form of the changed trajectory) and time (in the form of the difference in speed). Mass must be different than outside in space. Let us think back to the unsuspecting fish: The general theory of relativity provides further evidence that space and time are a four- dimensional "something". This formulation sounds strange, because how can "nothing" be curved? And yet it is true: on the surface of a neutron star, a celestial body made of highly dense nuclear matter, for example, there is enormous gravity. Using modern telescopes, we can prove that time passes much more slowly there than in the rest of the universe. Space is also compressed, although this is a little more difficult to measure. Conversely, for an observer on the surface of a neutron star, the processes outside in the universe would take place in fast motion. Every molecule, every process in our body, every electrical impulse in our brain is embedded in space- time and is part of it. So we have no chance of perceiving it as "something". But with the help of our modern physical measuring instruments, we are finding more and more evidence that space- time is indeed a substance. At some point, the state of "no space- time" may also be revealed to us. But that is still unthinkable given the current state of physics. Machine Translated by Google How do we come to the idea that space- time has energy and mass? This theory is based on so- called vacuum fluctuations. Let's imagine a cubic meter of empty space, carefully shielded from light and other external influences. According to the traditional idea, there is "nothing" in this area, that is, it contains neither electrons nor atomic nuclei nor photons. Accordingly, there should be no mass or energy in this imaginary place. But that is not correct. Quantum theory does not recognize the number zero, at least as far as the number of certain particles is concerned. In the context of the time- energy uncertainty principle, particle- antiparticle pairs are constantly created and disappearing in every cubic meter of space. This "zero- point noise" or "zero- point jitter" can be found everywhere, even in a completely normal mechanical pendulum. The same principle applies to the light in our cubic meter of space- time in nothingness. In the concept of quantum mechanics, the vacuum consists of fields such as the light field. The connection may not be immediately obvious. So let's take an old grandfather clock as an example. Space and time are therefore connected and must be treated mathematically as a four- dimensional unit. At the same time, similar to the speed of sound in air or water, there is a maximum speed, namely that of light. This also provides an indication that spacetime is more than just nothing. But science knows of an even stronger indication: spacetime has energy and therefore mass. This experimental observation provides us with proof. The only question that remains is whether other substances exist alongside spacetime. But that already takes us - and we are only at the beginning of the book - beyond the limits of knowledge. This sparkle is made possible by a second uncertainty relation, the time- energy uncertainty relation. For a tiny moment, a photon can appear from nothing – contrary to the overriding natural law of energy conservation. However, it disappears just as quickly, because it only exists on borrowed energy. This happens constantly and everywhere in every cubic meter of space- time. On average over time, the number of light particles is not zero, but has a very small positive value. This also applies to all other types of particles, as long as the laws of nature are observed. If, for example, an electron is created spontaneously within the framework of this time- energy uncertainty relation, then due to the conservation of angular momentum and charge, its antiparticle, a positron, must also be created at the same time. So, in nothing If you stop winding it up, the pendulum will eventually stop swinging. To us, it then looks as if it is completely at rest. To be on the safe side, we can shield it from all external influences such as a draft of air or light. Nevertheless, a very precise measurement will show that the pendulum is shaking. To be more precise, it is still swinging, but with an extremely small amplitude. This is the so- called zero- point oscillation, which the pendulum performs even when all its energy has been removed. It can still be measured even at the absolute lowest temperature. A residue remains, which in physics we call zero- point energy. The deeper cause of this is the wave- particle duality. Even matter like the pendulum, which supposedly consists only of particles, has a wave character and a wave cannot come to a complete standstill, because then it would no longer exist. This peculiarity of matter also forms the background for Heisenberg's uncertainty principle, here between position and momentum. According to her, it is not possible to determine these two properties precisely at the same time. This means that the pendulum cannot be in a precisely defined place with a precisely defined momentum at the same time. But that would be the case if it were at rest. In this state, the location could be determined precisely and the momentum would be zero. Therefore, the pendulum's speed must deviate. There is always a residual tremor. This means that the possibility of light existing even in total darkness is already inherent in the vacuum of space- time. And now this phenomenon of quantum mechanics occurs again, that there cannot be exa