Radioactive decays are random processes described by quantum theory, so we can’t say when one will happen. Quantum theory suggests that before you observe or measure an object, it exists in a “superposition” of all its possible states. Before we open the box, the atom is both decayed and undecayed – and the cat is neither dead nor alive, but in a superposition where it is both, neither, who knows. The act of looking seals the cat's fate, one way or another.
Part of the thought experiment is about the concept that information requires an observer. Atoms only become dots on a screen, and photons only activate cells on your retina because you exist to observe these phenomena from your unique viewpoint. These words do not exist as information without you, the reader.
You're probably wondering why I'm telling you this.
I realised recently that long before I knew anything about Schrödinger’s cat, I had an intuitive belief, an idea which seemed to serve me well, and I would like to share it with you.
Long ago, if I was awaiting news, such as a letter about a job application (in the days when we had letters, and when employers actually kept candidates informed), then I figured that up until the point that I opened the envelope and read the letter, the outcome of the interview was still undecided. I somehow felt that the letter would coalesce into reality at the point at which I opened the interview, and therefore I could somehow influence the outcome of that decision right up until the point at which I read, "Dear Mr Freeth, I am pleased to...."
I know what you're thinking. It sounds crazy, and if the letter turned out as I wanted, it just fuelled my confirmation bias, and I ignore all the times the letter carried unwelcome news.
I suppose the thought experiment that I am asking you to conduct is this: What if it were possible? What if possibilities only coalesce into reality when you the observer are present to turn patterns of matter into information? If a tree falls in the forest, you're thinking. What nonsense. Of course it makes a sound.
No, my friend. If a tree falls in the forest and no-one is there to hear it, it does not make a sound. It creates a shockwave through the surrounding air, but that shockwave is not a sound unless someone hears it.
What in your life could be influenced simply by your belief that, right up until the point that you look at the information, all bets are off?