During this weeks class we discussed some interesting topics again. One of the things we discussed was the Schrodingers Cat thought experiment.  In this weeks blog I have decided to look at this famous old experiment in more detail and try to understand a little more about the experiment itself and how it came to be in the first place.

Who is Shrodinger and why did he want to kill his Cat?

First up, if you don’t know about the experiment then you should watch this video, this is the quickest easiest way to understand and can explain it much better than I can:

Erwin Schrodinger was an Austrian physicist, who, in 1935 devised a thought experiment that involved a bunker, some gunpowder and a rather scared looking cat.

The experiment was intended to create a discussion about the EPR Article. The EPR article was named after its authors Einstein, Podolsky & Rosen, and was a discussion paper that highlighted the strange nature of quantum physics, in which a quantum particle, such as an atom can exist in more than one state at any time.

The theory that was  drawn from the EPR Article was called the Copenhagen interpretation and stated that an unobserved quantum particle can exist in multiple states simultaneously, this is called the Superposition.  It is only when the particle is observed or interacts with something that its superposition will collapse to one of the possible outcomes, basically nature is forcing the particle to show its hand.

Schrodingers idea was to take this interpretation that only works at the quantum level and to create a scenario at a much larger scale that would display the same characteristics.  So in his experiment the gunpowder is made up of particles that can decay at the quantum level and cause an explosion at the cat scale.  There is a 50/50 chance the gunpowder particles will decay and so we recreate the quantum physics at a larger scale.

Contrary to popular belief Schrodinger was not trying to back up the Copenhagen Interpretation, but was actually trying to find a way to illustrate how ridiculous it actually is.  Ironically though, as our knowledge of quantum physics has advanced, has become the case that most scientists agree that the cat experiment is a fairly valid premise.


Science actually managed to find some proof that quantum particles behave differently to bigger things (including cats) using an experiment called the DUAL SLIT.

Watch this quite wonderful way of explaining the dual slit experiment, an experiment which goes a long way to proving that there is some validity in the premise that observing an action can have an effect on it

The Dual Slit experiment was originally carried out by Thomas Young in 1801 and was used as proof that light behaved in the same way as a way.  It was only in the 1970s when science caught up and was able to actually watch which of the two slits electrons were passing through and they were suprised to find the action of watching the electrons actually changed the pattern that appeared at the receiver.

Subsequently, it seems we have found a way of observing the electrons without actually disturbing them


The dual slit experiment completely baffles science, however it does go a way to proving that the EPR Article has a lot of validity.

Science doesn’t have an answer for this one yet, lets call it a work in progress…..