Schrödinger’s Cat is a famous thought experiment devised by Austrian physicist Erwin Schrödinger in 1935.
It is often misunderstood as a scientific theory stating a cat can be “zombie-like” (alive and dead). In reality, Schrödinger created it to highlight the absurdity of the prevailing view of quantum mechanics at the time.
Here is a breakdown of the experiment, what it means, and why it matters.
1. The Setup
Schrödinger imagined a sealed steel box that contains the following:
- A live cat.
- A tiny amount of radioactive material (so small that there is a 50% chance one atom will decay within an hour).
- A Geiger counter (a device that detects radiation).
- A flask of poison.
The Mechanism:
If the radioactive atom decays, the Geiger counter detects it and triggers a hammer to smash the flask of poison, killing the cat.6 If the atom does not decay, the cat survives.
2. The Paradox (Superposition)
According to the principles of quantum mechanics (specifically the Copenhagen interpretation), subatomic particles like the radioactive atom exist in a state of “superposition.” This means the atom is simultaneously decayed and not decayed until it is measured.
Because the cat’s fate is entangled with the atom, the logic dictates:
Until you open the box to check, the cat is technically both alive and dead at the same time.
3. The Point Schrödinger Was Making
Schrödinger did not believe the cat was actually both alive and dead.
He used this scenario as a reductio ad absurdum (an argument that disproves a statement by showing it leads to a ridiculous conclusion).
- His argument: It is common sense that a cat is either alive or dead, regardless of whether we look at it.
- His critique: If quantum mechanics says the cat is both, then there must be a flaw in our understanding or language regarding how quantum rules apply to the macroscopic (everyday) world.
4. Two Major Interpretations
Physicists have debated the solution to this paradox for decades. Here are the two most common views:
| Interpretation | Explanation | The Cat’s Fate |
| Copenhagen Interpretation | Reality exists in all possible states until an observation “collapses” it into one state. | The cat is both alive and dead until the box is opened. The act of looking forces nature to choose one. |
| Many-Worlds Interpretation | Observation does not “collapse” anything; instead, reality splits. | The cat is alive in one timeline and dead in another. Both outcomes happen in parallel universes. |
5. Why It Matters Today
While we don’t worry about zombie cats, the concept is fundamental to Quantum Computing.
- Traditional computers use “bits” (0 or 1).
- Quantum computers use “qubits” (0 and 1 simultaneously).This “Schrödinger’s Cat” state allows quantum computers to perform massive calculations vastly faster than standard supercomputers.
Related Articles:
- Schrödinger’s Cat Wikipedia