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General Relativity Is At Least 99.95% Right
ultracool writes to mention a ScienceDaily piece on compelling proof of general relativity. A team at the University of Manchester have used three years' worth of data on a pair of pulsars as a litmus test, against which they've benchmarked Einstein's theory. From the article: "Though all the independent tests available in the double pulsar system agree with Einstein's theory, the one that gives the most precise result is the time delay, known as the Shapiro Delay, which the signals suffer as they pass through the curved space-time surrounding the two neutron stars. It is close to 90 millionths of a second and the ratio of the observed and predicted values is 1.0001 +/- 0.0005 - a precision of 0.05%. A number of other relativistic effects predicted by Einstein can also be observed. 'We see that, due to its mass, the fabric of space-time around a pulsar is curved. We also see that the pulsar clock runs slower when it is deeper in the gravitational field of its massive companion, an effect known as "time dilation."'"
Mathematics is a closed system, for which we know all the rules (because we define them). Thus, things can be proven as being objectively true, false, or unprovable (for as given set of axioms, there are many self-consistent sets).
Physics and the other sciences, on the other hand, are faced with the dilemma that we can never observe all the behaviour of everything in the universe at once, and thus we are forever working with partial data sets, and fitting our theories to them. As a result, the best we can say is that the theory we have put together fits the observed data to a high degree of precision - but that this may be invalidated at any time by new phenomena. See, for example, the progression from Newtonian mechanics to Relativity, or the long-running debate over the nature of light.