The Hafele-Keating Experiment Supports Special Relativity

AveSince I consider this resolution to be incredibly easy to defend, I will present a simple argument in favor of it.P1: If the Hafele-Keating experiment affirms the predictive power of special relativity (i.e. its consistency with experiment), then the Hafele-Keating experiment supports special relativity.P2: The Hafele-Keating experiment affirms the predictive power of special relativity.C: The Hafele-Keating experiment supports special relativity.In propositional logic, this is the modus ponens form of argument, where if p implies q, and p is true, then q is true. Since the argument is obviously logically valid, the only task that remains is to defend the truth of each premise.P1In the contemporary paradigm of the philosophy of science, the best indication of a good scientific theory is that it has predictive power. A scientific theory with predictive power is able to generate testable predictions. Predictive power differs from explanatory power in that it does not merely explain past events with the theory, but actually predicts future events. For this reason, predictive power is generally favored over all other aspects of a scientific theory. As the philosopher of science Alex Rosenberg stated in an interview with 3AM Magazine, “Science is common sense recursively reconstructing itself. The reconstruction reflects the fallibility of common sense. Insistence by science on the tentativeness of its results at its ever-shifting research frontier, is what gives us confidence that after repeated test the parts most distant from that frontier are unlikely to be called into question.”. In other words, confidence in science comes from repeated testing of the predictions that a scientific theory makes. For this reason, one cannot have a good scientific theory without predictive power. Therefore, an indication of a good scientific theory is its predictive power.What would predictive power look like in practice? If an experiment was conducted, and the outcomes were consistent with the theory (i.e. the outcome is what you would expect if the theory is true), then the experiment affirms the predictive power of the theory, indicating that it is a good scientific theory. From this, predictive power is consistency with experiment. In round one, I defined “supports” as “an experiment supports a scientific theory if its outcomes are consistent with that theory”. Based on this definition, we can conclude that “supports” also means “affirms predictive power”. Therefore, the resolution is equivalent to stating “The Hafele-Keating experiment affirms the predictive power of special relativity”.P2The Hafele-Keating experiment supports special relativity if its outcomes are consistent with the predictions of special relativity. What predictions would special relativity make for the Hafele-Keating experiment? Special relativity would predict that the rate of the clock is greatest when the observer is at rest with respect to the clock. In the Hafele-Keating experiment, the inertial reference frame was represented by the United States Naval Observatory. Hafele and Keating put four atomic clocks on airplanes, and then took the time that they measured after traveling around the world in an eastward, and then westward, direction. Since special relativity predicts that the rate of the clock is greatest when the observer is at rest with respect to the clock, then it would also predict that the clocks will lose time in the eastward direction and gain time in the westward direction. Did this actually take place? Yes. Hafele and Keating found that the clocks lost time in the eastward direction and gained time in the westward direction. As Hafele and Keating state in the abstract of their 1971 Science publication, "Relative to the atomic time scale of the U.S. Naval Observatory, the flying clocks lost 59 ± 10 nanoseconds during the eastward trip and gained 273 ± 7 nanoseconds during the westward trip". This means that the Hafele-Keating experiment was a success for special relativity, as it affirms the predictive power of the theory.The consensus in the physics community helps to establish the plausibility of this interpretation. Indeed, the notion that the Hafele-Keating experiment supports special relativity is so established in the physics community that it is taught in introductory textbooks. As Physics: Principles and Applications by Douglas Giancoli states, "Experiments have tested the time-dilation effect, and have confirmed Einstein's predictions. In 1971, for example, extremely precise atomic clocks were florm around the world in jet planes. The speed of the planes was much less than c, so the clocks had to be accurate to nanoseconds in order to detect any time dilation. They were this accurate, and they confirmed time dilation to within experimental error." As Stephen Hawking states in The Grand Design, "Imagine a reference clock at rest at the center of the earh, another clock on the earth's surface, and a third clock aboard a plane, flying with or against the direction of the earth's rotation. With reference to the clock at the earth's center, the clock aboard the plane moving eastward--in the direction of the earth's rotation--is moving faster than the clock on the earth's surface, and so it should run slower. Similarly, with reference to the clock at the earth's center, the clock aboard the plane flying westward--against the earth's rotation--is moving slower than the surface clock, which means that should run faster than the clock on the surface. And that is exactly what was observed when, in an experiment performed in October 1971, a very accurate atomic clock was flown around the world." C The conclusion follows logically from the premises. Since the conclusion is the same as the resolution, the resolution is affirmed. Vale