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Physicist Claims Time Has a Geometry
sciencenews writes to tell us that a physicist at Stanford has just recently published a peer review website for several physics lectures focusing on a single underlying idea that "time is not a single dimension of spacetime but rather a local geometric distinction in spacetime." The science is presented quite clearly and originally uses GPS systems as a point of focus. From the article: "Not too long ago, people thought the Earth was flat, which meant they thought that gravity pointed in the same direction everywhere. Today, we think of that as a silly idea, but at the same time, most people today (including most scientists) still think of spacetime as if it were a big box with 3 space dimensions and 1 time dimension. So, like gravity for a flat Earth, the single time dimension for the 'big box universe' points in one direction, from the Big-Bang into the future. A lot of lip service is given to the idea of "curved spacetime", but the simplistic 3+1 'box' remains the dominant concept of what cosmic spacetime is like."
Perhaps someone should tell him that general relativity has already been invented. Physicists know that time has geometry---it is, after all, a part of spacetime, which has geometry. With regard to his claim that GPS has unexplained anomalies, he may be right. However, GPS is based on the Schwarzschild metric, which assumes a non-spinning, point-like mass. The earth is neither of these. Accordingly, there will be small corrections due to the combined effect of earth's spin and its density profile. At present, we are unable to calculate those corrections (we've only solved some important special cases, because the math is so hard), but they almost certainly explain the GPS deviations.
"Einstein's relativity theory still remains a THEORY, seeing as how no one has actually tested the limits of it."
What has testing got to do with it? It will always be a theory, because that's all science can produce. If you want something definate you want mathematical theorems - those are known to be true. Theories never will be - they can just be very reliable at predicting things, nothing more.