Alive and Dead...part 4

I never really written a part 4 of anything before...this is a first for me...yayy!! Actually I have never written a part 2 or 3 either...I apologise for taking a little longer than i expected but with Valentines day just over, I was for the large part mulling over suicide...Quantum suicide that is :) (I get the feeling this is going to be a very very long post...so if u have some work to do, finish it and then sit down)
Now before I get down to it,I am going to have to repeat a couple of things which some of you might have already realised(if u have, dont read the next few lines) but for the benefit of those who did not---> the coin toss example I gave you was just an example, an analogy. It seemed simpler to explain with a coin toss rather than to start off with atoms and electron states. What did you people think?? That there exists states which were actually both head and tails for a coin?? Ridikulus!! :P
In my last post, I had talked about the cat experiment and the famous Copenhagen interpretation. Before I explain the concept of quantum suicide, lemme introduce another interpretation of QM which is very quickly gaining ground on the Copenhagen one. Lets first talk about what an "interpretation" means.
In science, a theory is accepted when in a very basic sense its internally consistent ie one idea of the theory doesnt contradict another and the theory can predict with great accuracy the results of experiments. Over the course of our existence, scientific theories have always sprung out in the pursuit of explaining our observations. Newton did not get up one fine day and formulate his 3 laws of motion or his theory of gravity. They came about by extensive observations of movement of the planets and comets (pls dont tell me you actually beleive the Newton-apple story!!). Bohr and other QMists did not out of the blue, come out with the basic postulates/ideas I had given before. It was how they believed the systems should work to explain the results they had obtained thru experiment and as long as their ideas were internally consistent and would explain the results they have already as well as predict for future experiments, the ideas or their "interpretations" is assumed to be correct. But that does not mean that there cannot be other interpretations. If you and I can come up with a new set of ideas which would satisfy the basic constraints that a theory should very rigorously, then voila!! we have a new theory in our hands and the coveted 3AM call from Stockholm
not far away.:)
I would be right in assuming that the idea of a "collapse" at first and maybe even now does not sit well with many of you. It didnt either for Hugh Everett III, one of the most brilliant minds of our time and probably one with the saddest of stories(http://en.wikipedia.org/wiki/Hugh_Everett_III). For his PhD dissertation, Everett suggested another interpretation of QM which went to form the infamous Many Worlds theory!! (Now thats a PhD dissertation!!). When Everett proposed this idea and spoke to many of the Copenhagenists like Bohr, etc he was ridiculed and termed an 'amateur' with no idea what QM really meant. This eventually led to him quitting his research in physics and moving onto algorithms for optimisation( OR and EM students might come across his work sooner or later). However for a while now, his many worlds theory is gaining increasing popularity and catching up with the Copenhagen interpretation( and for whats its worth, it has definitely won me over).
The many worlds theory is an idea which sounds a lot more appealing cos we have come across it a lot, in movies, on TV, fiction stories, they make a very good read. But trust me, the concept of many worlds isnt just fiction. It is a very real science and one whose mathematics is a little simpler than the one related with the old interpretations(one of the main reasons why its gaining a lot of popularity nowadays). As the name suggests, the theory implies that there exists many worlds, probably infinite in number in which one of every possible outcome has occurred and these multiple universes do not interact. That is anything that could have possibly happened in the past did actually happen but in different universe to the one you are in. To put it simply, consider the Schrodinger cat experiment again. The old interpretation means that the cat will be "alive" or "dead" only after you observe it. This means you, the observer caused that. But in the many worlds theory, the cat is either "alive" or "dead" even before you observe but you in THIS universe will see only one of the two outcomes.Still confusing? Very simple, if I opened the box and saw a dead cat it means the cat was dead even before I opened the box BUT in another universe (which is instantaneously created by the mere fact that the cat could have been alive) I will open the box to see a live cat but since the two universes cant interact or communicate with each other, we only behave as though one of the things happened!! Think about it, makes sense doesnt it?
This effectively means, everytime you perform an experiment and it can have any one of possible outcomes, everyone of the outcome does occur but you continue to exist in the universe where you see the outcome that you get. And the 'you' in the other universe might have got a different outcome but to him/her that is the outcome of the experiment.OMGGG!!! this means the power of choice literally SPLITS the universe everytime!! My friends, do not underestimate the power of choice that you possess!!
Now lets get down to the fun part of what this means. I started off, talking about Quantum suicide. This is an infamous implication of the many worlds theory. Lets say one day a person A suffering from a broken heart, decided enof's enof and takes a gun to kill himself. He pulls the trigger and one of two things can happen. The gun either fires or it doesnt, which implies the A either lives or dies. Now the many worlds theory states that the universe splits to accomodate both outcomes, ie both events occur but we in this universe experience only one of them. If the gun fires and A dies, he is dead and the universe cannot split based on him pulling the trigger anymore but it can continue to split based on other things like say B who is in love with A decides to take up that gun and pull the trigger.
But but..its a lot more interesting if the gun doesnt fire and A lives. It means we are in the universe where A lives and... Now A can once again pull the trigger==>there is a chance of one of two possible outcomes happening AGAIN!! Again the universe will split and will continue splitting till he dies.This is the concept of Quantum suicide. But waaaaaiiiittt a minute, even if he dies, it means the act of pulling the trigger has created an universe where he lives and if we just kept doing this, there will always be an universe where he continues to live. Does that mean the person will live forever?? Infact thats exactly what it means. The person will infact attain what is called QUANTUM IMMORTALITY!! uahahahahahahahaha but it will occur in only one of infinite universes!!
Its quite amazing to think that reality isnt a straight line but infact a brach in a huge tree of time!! Anyways this theory and the Copenhagen interpretation predicts results which are the same or very similar for a wide range of experiments and hence there is no way for us to correctly determine which one is right and the other wrong. Infact finding actual cases where one theory might usurp the other is focal point of research nowadays and is a sure shot way to win the Nobel. Maybe they are both wrong!! Maybe there is something out there that we have all been missing!! Ahh the wonders of this universe!!
Chal, I shall take up no more of your time. Hope u guys enjoyed reading this as much as I enjoyed it writing it. I shall see you in part 5 :)

Natesh
ps: a little cartoon explaining the many worlds theory. one of my favorites. I had put this up in FB a while back. Note the reference to the cat right at the end :D
http://abstrusegoose.com/240