Do you know Schrödinger’s cat?

Do you know Schrödinger’s cat?

Schrödinger’s Cat is a famous thought experiment devised by Austrian physicist Erwin Schrödinger in 1935 to demonstrate how much quantum mechanics contradicts our everyday logic.

This experiment was developed to prove how absurd the behavior of particles in the quantum world (superposition) can seem when applied to a macroscopic world (a cat).

Experiment Setup

The following items are placed inside a steel box:

A live cat.

A radioactive source: A setup is arranged such that there is a 50% probability of the atom decaying within one hour and a 50% probability of it not decaying.

A Geiger counter: If the atom decays, the counter detects it and triggers a mechanism.

A poisonous gas apparatus: When the mechanism is triggered, a bottle of poisonous gas breaks, killing the cat.

The Core Contradiction

According to quantum mechanics, as long as no observation is made, the radioactive atom is both decayed and undecayed. This state is called “superposition.”

Since the cat’s state depends on the atom’s state:

According to the Copenhagen interpretation of quantum mechanics, until we open the box and make an observation, the cat is both dead and alive.

When we open the box, the “wave function collapses,” and the cat assumes a single reality, either dead or alive.

Why Is This Experiment Important?

Schrödinger devised this experiment not to support quantum mechanics, but rather to criticize how absurd results quantum theory could yield. Schrödinger meant to say: “An atom might be both decayed and undecayed, but a cat cannot be both dead and alive at the same time; this is physically impossible.”

Schrödinger’s cat opens the door to immense philosophical discussions about the nature of reality and the role of consciousness, rather than just pure physics.

The philosophical dimension revolves around three fundamental questions:

1. Does the Observer Create Reality?

According to the Copenhagen interpretation of quantum mechanics, the cat is both dead and alive until we look; but when we open the box, the cat is forced into “a single state.” This situation raises the frightening philosophical question: Does the universe exist as an uncertain “sea of possibilities” as long as we don’t observe it? If there is no observer, can we speak of reality?

1. Is Objectivity Possible?

In classical philosophy, the understanding “objects are there and fixed whether we look or not” (realism) prevails. However, this experiment argues that the observer determines the outcome by interfering with the system. This is a severe blow to science’s claim of being “objective.” If every measurement causes a reality to form (and other possibilities to disappear), what is “real”?

1. Many-Worlds (Parallel Universes)

One of the most striking views put forward to escape this philosophical impasse is the “Many-Worlds Interpretation.” According to this view, when you open the box, the cat does not remain dead and alive; the universe splits into two:

In one universe, you open the box and the cat is dead.

In the other universe, you open the box and the cat is alive.

This perspective argues that the universe constantly branches at every moment; meaning every time you say “if only,” it has happened in another universe. This sits at the heart of determinism and free will debates.