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swankdave
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- TL;DR Summary
- In a single object universe would Gravity eventually stop all light?
Googleing this question yields answers that don't really seem to address the core of my question. I apologize if I just haven't been able to see how answers are applicable, and would greatly appreciate any insight.
Imagine a universe consisting of only our sun. no planets, no galaxies, nothing else but the void. Ignoring the fact that at some distance the light from this star becomes so dispersed as to be, for all practical purposes, undetectable; is there a distance at which the light will, please excuse the phrase as I know light always moves at the speed of light, reverses course, due to the gravitational force of the star? This is a separate question than "can the universe expand forever" as, at least it seems to me, objects with mass could still expand forever, even if light cannot ultimately outpace the warping of spacetime of its source. (mass has the momentum to counteract space-time curvature, light does not, at least I think it doesn't)
The implication here would be that all objects would eventually be considered a black hole at a sufficient distance, depending on the distance between the source of the light transmission (the surface of the sun in this case) and the Schwarzschild radius for the mass of the given object. In my head, this seems congruent with the existence of Cosmic Background Radiation, but that is likely a faulty assumption.
To put it another way, I understand that light emitted within the event horizon of a black hole cannot be seen by the outside observer. However, light from something approaching the event horizon undergoes redshift at a rate of something like v=1/sqrt(1-(d-r)). (v is apparent velocity from redshift, d is the distance to the center of mass, r is the distance from the event horizon to the center of mass) One, such as myself, might be tempted to infer that the distance light will travel from a gravitational source could be related to the integral of a formula like the one above between the distance of transmission to an observer approaching the speed of light, which, given the asymptotic nature of the formula, I would think must happen eventually? (I apologize, my calculus isn't great here, and my assumption that the integral of a horizontal asymptote with a limit of zero isn't itself limited doesn't feel quite right, but I'm proposing it anyway.)
Sorry for the rambling nature, your insight is greatly appreciated.
Imagine a universe consisting of only our sun. no planets, no galaxies, nothing else but the void. Ignoring the fact that at some distance the light from this star becomes so dispersed as to be, for all practical purposes, undetectable; is there a distance at which the light will, please excuse the phrase as I know light always moves at the speed of light, reverses course, due to the gravitational force of the star? This is a separate question than "can the universe expand forever" as, at least it seems to me, objects with mass could still expand forever, even if light cannot ultimately outpace the warping of spacetime of its source. (mass has the momentum to counteract space-time curvature, light does not, at least I think it doesn't)
The implication here would be that all objects would eventually be considered a black hole at a sufficient distance, depending on the distance between the source of the light transmission (the surface of the sun in this case) and the Schwarzschild radius for the mass of the given object. In my head, this seems congruent with the existence of Cosmic Background Radiation, but that is likely a faulty assumption.
To put it another way, I understand that light emitted within the event horizon of a black hole cannot be seen by the outside observer. However, light from something approaching the event horizon undergoes redshift at a rate of something like v=1/sqrt(1-(d-r)). (v is apparent velocity from redshift, d is the distance to the center of mass, r is the distance from the event horizon to the center of mass) One, such as myself, might be tempted to infer that the distance light will travel from a gravitational source could be related to the integral of a formula like the one above between the distance of transmission to an observer approaching the speed of light, which, given the asymptotic nature of the formula, I would think must happen eventually? (I apologize, my calculus isn't great here, and my assumption that the integral of a horizontal asymptote with a limit of zero isn't itself limited doesn't feel quite right, but I'm proposing it anyway.)
Sorry for the rambling nature, your insight is greatly appreciated.
