Sunday, July 10, 2011


Some theoretical physicists, most notably Stephen Hawking and several super-string theorists have frequently foretold that we will soon know nature's ultimate natural law(s). That is, that the theoretical recipe book will finally be complete and can be printed with permanent, waterproof ink... This also was Einstein's dream during the final thirty years of his life, and there is indeed an aesthetic, almost magical attraction to the search for the "final formula"; one grand unified "theory of everything" (TOE), which ideally should be summed up so short to fit on a postage stamp, or at least a T-shirt. However, there is much to be said against such a dream, and the TOE today is less valuable than a pinkie:
Even if there is such a description of nature, which is far from certain, why should we - just today - be able to obtain complete knowledge of all the secrets of the universe, its origins and ultimate fate? We humans would never imagine that amoebas have a correct theory of everything, but if there are ancient civilizations that are just as far beyond us in development as we are above amoebas, how big is the probability that we will have the same TOE as they?
If an "ultimate" theory eventually is constructed, will it then be possible to test it through experiments and/or observations? This is, after all, the foundation of all exact science; it must be possible to test the theory and its predictions against nature itself, as the only raison d'ĂȘtre of the theory is its capacity to describe nature. It is in fact what is meant by the very concept of physics. But unless a major technological breakthrough is made, we will soon have reached the limits of how powerful particle accelerators we can manufacture.
Even though the known fundamental forces of nature - three or four, depending on how you count - are all relatively simple, it is almost always impossible to make detailed predictions of the behavior of even mildly complex systems starting from those laws. Is that a fundamental property of nature itself or simply a consequence of our theories being formulated in a manner which is far from ideal?
The concept of "building blocks" may be meaningless at the fundamental level. A reductionist approach - that things are made of smaller things - is subconsciously ingrained, particularly in the western world. However, it is possible that there may be principles of nature that differ from the hierarchical structure of the natural laws known today.
Physics is the science of nature, but our theories should be short, simple summaries of the complex world. A theory that can contain everything probably must be... nature itself! In recent years, particularly within chaos theory and quantum physics, one have also realized that it is very important to distinguish between the model (natural law) and what it models (the observed phenomenon). A theory which is of practical use will always miss some things because it otherwise would lose its entire reason for existing; which is to simplify the description. Therefore, a TOE, a definitive theory/formula that applies to the entire universe and everything in it, will probably forever be an unattainable dream.

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