Mark's First 20% Time Update - String Theory

I’m researching possibly one of life’s most important yet so far unanswered questions – how can we explain the world around us in simple terms? String theory seems to suggest a plausible answer. My project investigates what this may mean. Questions that have arisen so far are:

What is string theory? What it means to the world? What is its significance? Is there is any evidence for it? Is it yet another dead end in Physics? Why don’t the theories of relativity and quantum correlate? Why are so many research institutes funding string theory research if there is no conclusive evidence of it so far? Could particle accelerators such as CERN provide some evidence that may eventually lead to a solution (it's just finished getting a 2 year renovation)? How far away is this solution? What are the alternatives to string theory?

As we start to understand more and more about science and particularly physics, we start to realise that the simplistic model of the atom with electrons spinning around a nucleus starts to break down drastically. Why don’t negative electrons spinning around a positive nucleus suddenly collapse into it? After all, don’t opposite charges attract? It turns out that the answer is not as straightforward as it seems. This is one of the issues that quantum theory attempts to solve and it provides part of the premise of my project. Another part is the idea of relativity which Albert Einstein postulated back in 1905. It suggests that all motion is relative to a frame of reference and that space and time are relative, not absolute quantities. The problem is that the quantum world doesn't seem to agree with relativity. This is what string attempts to unify.

I started off resuming Lee Smolin’s The Trouble With Physics which I started reading back in 2009 on a train in Italy (I even found the train ticket from Bologna to Milan that I was using as a bookmark). It gives an account of the state of modern physics and the problems it currently has. The five problems that Smolin lists are:

1. unify quantum theory and general relativity to come up with a complete theory (an example of two ideas that were successfully unified is electricity and magnetism which we’ll meet later this year in our unit on electromagnetism)
2. explain quantum theory in more simple terms or invent a new theory which does
3. determine whether or not all fundamental particles and forces can be unified in a single theory
4. explain the free constants in the standard model
5. explain dark energy and dark matter and if they don’t exist, explain why gravity changes on large scales

However, I realised quickly that I needed to backtrack and review quantum theory as I had forgotten much of what I had previously struggled to learn. I then picked up a copy of Manjit Kumar’s Quantum: Einstein, Bohr and the Great Debate About the Nature of Reality which is a book I’ve heard great things about. Sure enough, I wasn’t let down. Kumar has done a fantastic job of outlining the history of the debate since Max Planck unwittingly started the revolution back in 1900 when he suggested an equation for blackbody radiation (A blackbody is a perfect absorber and emitter of radiation.).

1900 may not seem that long ago, but back then the concept of electron was very much a new idea. JJ Thomson ‘discovered’ them a couple of years previously in 1897. There was much controversy back then regarding even whether atoms existed but it was Albert Einstein in 1905 (a particularly fruitful year for him) who finally proved that atoms were real with his paper on the mathematical analysis of Brownian motion which proved Dalton’s atomic theory. Kumar goes on to outline the theories, the characters, the experiments, the debate and the controversy which raged for over half a century surrounding the nature of the quantum world. It was this nature that led Erwin Schrödinger to pontificate “Did God play dice?” as he questioned if the universe and everything in it could be reduced to a bunch of statistics.

One of the most striking things that has been revealed to me is just how much debate there was and there still is regarding some aspects of science. Science has never been as easy and as clear as a school textbook presents it and I believe much of the debate is lost in a bid to reduce everything to a simple model for students. I think this is a big problem as many people then take science to be a bunch of facts to be memorized without really understanding the nature of how science works.

I’ve also recently started reading John Gribbin’s In Search of Schrödinger’s Cat as I attempt to further my understanding of the quantum debate from a different perspective. In my next blog post, I’ll share more of what I read and learned from both books before I get into the string theory aspect of it. One of the issues I’m having is that I read Kumar’s book cover to cover in less than 48 hours, but I’m finding that since I didn’t make any notes from what I was reading, it’s making it difficult to think back now. Now I’ve started a separate notebook in Evernote to help me compile notes.

Thanks for reading,

Mark

References

Gribbin, J. (1984, 2012) In search of Schrödinger’s cat: Quantum physics and reality. London: Black Swan.

Kumar, M. (2008). Quantum: Einstein, Bohr and the great debate about the nature of reality. London: Icon Books Ltd.

Smolin, L. (2006) The trouble with physics. London: Penguin Books.