| > The only thing that can change the direction of motion of a particle is a force. Quite false. You're overlooking the fact that photons are the carrier particle of the electromagnetic field, which takes the form of waves in space -- waves that change direction without the application of forces. An optical lens changes the direction of photons without exerting a force. So does curved spacetime. These are examples of hundreds of things about physics that contradict your outlook. Also, masses respond to gravity by changing direction, and gravity is not a force: http://curious.astro.cornell.edu/physics/140-physics/the-the... Again, at 1.5 times the radius of a black hole, looking tangentially, you would see the back of your own head. So even in this local frame of reference, light has taken a curved path along with curved spacetime. In other frames of reference, light is obviously not traveling in straight lines. In fact, it can be argued that light never travels in straight lines -- that would be true only in a universe without any mass at all. You could argue that water always travels along straight lines inside a pipe and never changes direction, and in the case of the pipe itself changing direction, you could argue that the water is always traveling in a straight line from its own perspective inside the curved pipe, but having said that, people would see your ideas for what they are. > Any physics professor will understand precisely what i'm saying, and all agree. You appear to have forgotten I have already disproven this with my John Wheeler quote: "Mass tells space-time how to curve, and space-time tells mass how to move." As with masses, so with photons. If masses could travel at c, they would take the exact path photons do -- curved ones. |