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Problem 1.10

10 November, 2015 - 14:52
Let t be the time that has elapsed since the Big Bang. In that time, one would imagine that light, traveling at speed c, has been able to travel a maximum distance ct. (In fact the distance is several times more than this, because according to Einstein's theory of general relativity, space itself has been expanding while the ray of light was in transit.) The portion of the universe that we can observe would then be a sphere of radius ct, with volume v=(4/3)\pi r^3=(4/3)\pi(ct)^3. Compute the rate \dot{v} at which the volume of the observable universe is increasing, and check that your answer has the right units, as in Example

Solutions for chapter 1