Nineteenth-century physicists wanted the atom to be composed of discrete particles—electrons—moving around a center—the nucleus—in strictly defined orbits, as in the macrocosm of the universe: the Moon around the Earth, the Earth, and other planets. around the sun, the sun around the center of the galaxy, and so on. The realm of gravity and the straight arrow of time, imperturbable and steady, the Universe is like a well-tuned clock, as Newton wanted it to be (and as we all still perceive it in our daily lives). However, in the first decades of the twentieth century, the international scientific community of physicists began to single out in matter, and especially in the microcosm of the inner individual, phenomena that contradict all human logic, even the laws that govern nature at the macrocosmic level. .

This rough summary concerns the genesis of quantum physics. Quanta: beams of particles. If the theory of relativity has upended the fundamental concepts of space and time, then at about the same time, quantum physics has overturned centuries-old concepts and ideas about matter.

In the world of microparticles, matter is changeable and mysterious. At the bottom of the minimum, another infinity opens again, in which it is impossible to know the exact position of the particle or its energy state. Therefore, it is meaningless to say that the defining event has happened until you observe its result. This is a fascinating story told by science historian David Kaiser in his book The Quantum Legacy. Answers from an Uncertain World, published these days by the Ropi publishing house (translation-scholarly editing: Grigoris Panoutsopoulos – Themistoklis Halikias). As he writes, “While in our lives we are often confronted with disjunctive decisions like ‘one or the other’, nature — at least as described by quantum theory — can accept ‘both together’.” And here and there or, the deaf end of madness, both the living and the dead. More on this later.

The world of research by the giants of physics in the 1920s, from Niels Bohr and Werner Heisenberg to Erwin Schrödinger, Paul Dirac, Einstein himself and others, is unimaginably small, but at the same time huge and exciting. What does an atom contain at its core? Beams of protons and neutrons, which in turn are made up of the famous quarks (a word physicists stole from James Joyce). Everything we touch is made up of electrons and quarks bound together by gluons—and that’s our entire world, even if we don’t perceive it as such.

But what is happening now? After a series of complex experiments in the microcosm of the atom, physicists saw that electrons change trajectories arbitrarily, violating the fundamental principles of mechanics. They saw that an electron can be in two different places in space at the same time. They discovered that these are fundamental properties of subatomic particles: they mysteriously disappear and reappear in the microcosm, where everything is unstable and flirts with nothing, making incredible leaps from one interaction to another.

Fundamental particles are short, ephemeral entities that are constantly created and destroyed through an endless series of unpredictable movements. How can an electron be in two places at the same time? Existence ceases to be a body and becomes a ripple, a wave function, according to scientific terminology. This is not a world of certain things and solid objects, this is a world of indefinite, indefinite events. Einstein himself was horrified by these discoveries (then he wrote the famous phrase “God does not play dice”, although he contributed to new physics by discovering photons, a component of light.

At the bottom of the minimum, another infinity opens again, in which it is impossible to know the exact position of the particle.

Einstein wasn’t the only one who didn’t like this… mystical aura of quantum physics. And other scientists who contributed to the development of quantum physics rejected some of its basic postulates, especially as they were formulated by the famous “Copenhagen School” (this incredible story also inspired the creation of the play “Copenhagen” by Michael Frain). One of them was Erwin Schrödinger, who is also supported by Kaiser in his book. His theoretical experiment with both a dead and alive cat in a box was essentially a brilliant irony against the quantum approach promoted by Copenhagen.

“The story is about a cat locked in an opaque box with radioactive material,” Kaiser describes. “If the radioactive material decays, the device will detect the decay and release a hammer that will shatter the glass container containing the poison and kill the cat. If no radioactivity is detected, then the cat will live. Schrödinger came up with this disgusting scenario to criticize a feature of quantum theory that he considered outrageous. According to proponents of the theory, before opening the box to check the cat, he will be neither alive nor dead, but will be in a strange, purely quantum state of life and death.

Kaiser makes another interesting point: “While Schrödinger’s cat thrives as a meme to this day, discussions about it tend to overlook a key aspect of the story: the environment in which Schrödinger invented it. It is no coincidence that in the face of the prospect of a coming world war, genocide and the decay of the German intelligentsia, Schrödinger’s thoughts turned to poisons, death and destruction. Thus, Schrödinger’s cat should remind us of something more than the bewitching oddity of quantum mechanics. This should remind us that scientists, like us, are people who feel and are afraid.”

It is important to emphasize here that a macroscopic object, such as a cat or a bottle of sodium cyanide, cannot be assigned a quantum wavefunction. Only in microparticles. In other words, all these paradoxes are applicable only in the microcosm. Our bodies, planets and galaxies do not obey quantum laws and their paradoxes. But here’s a terrible contradiction: how is it possible that the particles that make up the universe behave like ghosts, and we don’t? Because that’s who we are. This is what we are made of, our body, the Earth, the planet Jupiter, the Sun, everything. But the Earth and Jupiter are fixed at a certain point in space, moving along certain orbits. Our bodies are the same. Isn’t this crazy? Is this a terrible contradiction?

“No one understands quantum mechanics,” said Nobel Prize winner Richard Feynman, referring to the gulf that separates quantum reality from living human experience. Kaiser’s book touches on this mystery in several ways.