One day in 1926 Erwin Schrodinger wanted to explain quantum mechanics in simple terms.
 
  A consequence of quantum theory is that one cannot the exact position of a sub-atomic particle, or the exact time when one particular atom of a radioactive substance will emit a particle.

  For example imagine a hydrogen atom which has one large proton as its nucleus and one small electron circling round it. But in fact the electron does not circle round it but is spread out in what is called a wave function.  If I think of it as a particle then the probability will be highest that the electron will be in a position where the wave function is densest.

  There is a certain lowest energy that the electron can have. If the electron absorbs one photon of light energy it is raised to a higher energy level.  The wave function of the electron will then occupy a larger volume.

However the electron cannot possess energy somewhere between quantum state on e and quantum state two. It can only absorb energy in discrete packets.  Its absorption of energy is in a digital form, not an analog form.

However I cannot know whether a certain hydrogen atom is in quantum state 1 or quantum state 2 until i go and observe it.  So I imagine that it oscillates between quantum state one and quantum state two until I go and observe it when I will find that it is in a definite quantum state, either 1 or 2.
Erwin Schrodinger first deduced the equation for the wave function of an electron.  He also wanted to describe it in simple words.
So Erwin Schrodinger substituted a cat for the electron. The cat was contained in a box, where a tube of radioactive substance was suspended. In the course of an hour the radioactive substance may emit one charged particle.  On the other hand it may not.
Unfortunately for Schrodinger's poor cat, when the particle is emitted it triggers a hammer which smashes a tube of poison gas which spreads throughout the box and kills the poor cat.

Until Schrodinger observed it he did not know the cat was alive or dead. It could be in oscillating between being dead or alive.. In Schrodinger's mind was the idea that his observation decided whether of not the radioactive substances had emitted the particle..

This was only a thought experiment. It was never performed.  But Schrodinger could just as well have done without the idea of a cat being alive or dead used to describe the wave function (called by physicists the psi function) of an electron.

Electrons and other charged particles are never either alive or dead. They do not know the concept of life.  Does the thought experiment of the cat make quantum theory any clearer?  What do you think?

It is just as easy to imagine the particle itself as a particle- wave function either in quantum state 1 or 2  or spread out between the two when we are not observing but always in a definite quantum state either 1 or 2 when we are observing it. We can observe the electron by the trace it makes in a cloud-chamber. It is even easier to observe alpha particles because they are larger. Alpha particles are helium nuclei, (i.e positively charged helium atoms) which are emitted by many radioactive substances and can be observed using a scintillation counter (e.g a zinc-sulphide screen) which produces flashes of light when a charged particle hits it.

I think that we can do without imaging diabolical things happening to cats! I have noticed that the example of Schrodinger's cat is seldom used in modern physics text-books.

My cat Ashley is very glad about that!