When you’re studying quantum physics, it’s like trying to interpret Shakespeare’s Hamlet – if suddenly
everything make sense and you think you’ve finally got a handle on it, you probably understand less
than the guy sitting next to you with his head in his hands.
Schrodinger’s cat is a thought experiment, sometimes described as a paradox, devised by Austrain physicist Erwin Schrodinger in1935. The scenario shows a cat that may be simultaneously both alive and dead, a state known as a quantum superposition, as a result of being linked to a random subatomic event that may or may not occur. The thought experiment is also often featured in theoretical discussions of the interpretations of quantum mechanics.
All right, let’s make this more understandable.
At its most basic, the thought experiment dreamt up by Austrian physicist Erwin Schrodinger in1995 goes like this: you put a cat in box with some live explosives that have a 50/50 chance of exploding once you close the lid. For your purpose, this is a magical, explosion – proof box tht shows no sign of what’s actually happened on the inside.
The last point is the key – the deal is that the fate of the cat is unknown to you until you open up the box. So in other words, until you open the box, the cat occupies two state simultaneously - dead or alive.
Sounds pretty simple, right? Well, it’s not. What’s tricky about this hypothetical scenario is that for as long as we keep that box lid closed, the cat is in What’s known as a superposition state – it’s both dead and alive, because it has to be one, and it can’t be neither.
Once we open the box, our act of looking forces nature’s decision. So in a way, our curiosity kills the cat.
But then again, us looking on the box can’t change the reality of what’s already happened in the box – nature has already made that decision. Well – the above is only from our perspective, but what about the cat’s perspective?
Because the cat can actually see what’s happening inside the box, its experience is entangled with the outcome of the experiment, and it’s our observation of the experiment that causes nature to ‘collapse’ into one option or the other. The reality might be that there is only one real option, but until we observe that reality, the two option stand.
Now, if you take a step back from this scenario where we are looking at a box with an alive cat inside and a box with a dead cat inside, and think about the perspective of someone looking at you looking at a box, things become a whole lot more complicated. If you are looking inside the box collapses the two possibilities into one reality, who’s looking at you to make your act of box - opening a reality?
No, I’m not talking about god, but this is one of the most confounding questions in physics, and one explanation could be that there are infinite parallel universes that cater to every possible option for every possible scenario. So far there has been many interpretations of quantum mechanics have been proposed that give different answers to the questions posed by Schrodinger’s cat of how long those superposition and when (or whether) they collapse, like – Copenhagen interpretation, the many world interpretation, ensemble interpretation, relational interpretation etc. Also if you want, you can find descriptions of these interpretations on the net, and they are pretty amazing.