Some people claim they can trade by just reading charts. I am not one of them.
However, marketplaces that are crowded with technical traders will have the ability to be successful in the short run. The technical end of the stock market are zero-sum gamers employing algorithms that take advantage of weaker algorithms.
Thus, I do believe in the validity of technical analysis. I just don’t think many people can do it – at a minimum if you are not cognizant of your “enemies” (i.e. other traders) are up to, then you are the proverbial fish around the poker table.
One branch of physics, called econophysics, heavily depends on technical data to drive conclusions. Back in my university days, I dabbled in an econophysical model which was an interesting study. Some professors have taken it to the next level, and have mined technical data to try to predict market crashes, with partial success.
In absence of fundamental data, the model might be successful in predicting algorithmic activity, rather than being a crash predictor.