In addition to physics nerds, the Schrödinger’s cat it is also known to some fans of the series The Big Bang Theory.
Today we explain the role of feline in one of the most famous paradoxes of modern physics.
The laws of nature in the macro and microcosm
What is Schrödinger’s cat? It is an experiment that deals with the different physical laws for the micro and the macrocosm.
The macrocosm
Let’s first look at the macrocosm. That means all that we can see with the naked eye: At first glance, all living things and objects in our daily life are always in one place and have concrete values.
For example, the cat Merlin, despite its magical name, cannot lie on the sofa and in a comfortable bed at the same time, just as it cannot weigh four and five kilograms at the same time.
The microcosm
However, these rules do not apply to the microcosm and therefore to what it describes quantum theory. It deals with the smallest particles such as atoms or electrons.
However, according to the principles of quantum theory, these can be in several places at the same time and have different properties.
For example, an atom can decay and not decay at the same time. Quantum physicists refer to this state as “coherent overlap”.
Schrödinger’s cat: a famous thought experiment
Sound strange? This is exactly what the Nobel laureate and Austrian physicist Erwin Schrödinger wanted to clarify. In 1935 he invented a thought experiment that took the different laws of the macrocosm and the microcosm to an extreme.
Decades before the trend of cat videos in cardboard boxes went viral, Schrödinger placed a live cat in a box.
This gave him worldwide fame. To reassure worried cat fans: Schrödinger’s cat was purely fictitious – neither the feline nor the box existed. Schrödinger describes his experimental setup as follows.
Experiment: Alive or Dead Cat?
And radioactive atomand Geiger counterand hammer connected to it, a jar of poison it’s a gatto I’m in a closed box.
When the radioactive atom decays, the Geiger counter will indicate this and activate the hammer, which will destroy the vessel with poison. Then the poison comes out and causes the death of the feline.
However, it is unclear if and when the atom decays. According to the rules of quantum mechanics, the atom is in what is called a “coherent superposition” while we are not observing it. Experts speak of “superimposition”: it is neither decayed nor undecayed.
The expression “Schrödinger’s cat” means, according to the laws of quantum physics, “neither dead nor alive”.
Only when we open the box do we see a dead cat or a live cat.
What does Schrödinger want to tell us with his cat?
It’s a pretty confusing concept so far, isn’t it? Simply put, Schrödinger wanted to show the conflict between the natural laws of the macrocosm and the microcosm with the fictitious experimental setup.
Since a cat is not a quantum object, it cannot be alive and dead at the same time, even if its state depends on a quantum object. The laws of the macrocosm clearly state that at any moment the animal must be dead or alive.
However, if you delve into the world of physics, new dimensions open up based on the thought experiment of Schrödinger’s cat. For example, the “many worlds theory” states that both possible states become real: the cat dies, the cat stays alive. But these two realities take place in different universes. The result would be countless parallel universes.
Schrödinger’s cat in series, games and books
Schrödinger’s cat offers interested parties a lot to think about. With it, however, it is also possible to relax: those who do not want to immerse themselves so deeply in quantum physics can look after Schrödinger’s cat comfortably lying on the sofa. The icing on the cake is of course your cat on your lap! Schrödinger’s cat offers some steep passages to put a smile on your face.
In an episode of the sitcom The Big Bang Theoryphysicist Sheldon Lee Cooper tries to help his neighbor solve relationship problems using Schrödinger’s thought experiment.
Also other series like Doctor Who e FuturamaPC games such as World of Warcraft and famous authors such as Douglas Adams e Terry Pratchett they use references to what is probably the most famous cat in science.