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Please can You answer does gravity bend al frequencies of em-waves in the same way or not and why?

The simple answer is that for all practical purposes, it does.  It doesn't really "bend the light," light travels in straight lines in empty space.  But gravitation bends space itself, meaning that a straight line is not longer "straight" relative to an outside observer.  All light travels in straight lines, so all frequencies will basically pass in and out of a gravitational field at the same angles according to an outside observer.

However, if you want to get really picky, there are a few things to consider.  Because the graviational fields are asymmetric and light has a wavelength, parts of a truly large electromagnetic wave might have enough of the wave spend time in the truly stronger parts of the gravitational field.  It wouldn't bend much more than a tighter wave, and diffraction effects (if you want to get into quantum theory) cause waves to scatter from interacting potentials...putting us into the realm of quantum scattering probability and throwing off certainty about how the light would bend in the field.  This effect would be unmeasurably tiny, since diffraction is typically measured for things of similar size to the wave...and gravitational fields capable of producing bending of light are many, many orders of magnitude larger than the wavelengths of light we can observe with even the best low-frequency radio telescopes.  So you can't prove it, but it would be a ridiculously difficult problem to torture a graduate student with.


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Dr. Stephen O. Nelson


Fusion, solar flares, cosmic rays, radiation in space, and stellar physics questions. Generally, nuclear-related astrophysics, but I can usually point you in the right direction if it's not nuclear-related or if it's nuclear but not astrophysics.


Just moved from being a physics professor at the University of Texas of the Permian Basin into government work. Doctoral dissertation was on a reaction in CNO-cycle fusion, worked in gamma-ray astronomy in the space science division of the naval research laboratory in the high-energy space environment branch.

Government work as a physical scientist with a nuclear focus.

Ph.D. in physics, research was on nuclear fusion reactions important in stellar fusion, further work on space telescope technology.

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