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Debate:If the universe is young and it takes light millions of years to reach us from far off stars, how can we see them? (view source)
Revision as of 18:17, June 5, 2008
, 18:17, June 5, 2008→Signs of C changing
:Indeed, part of the problem with light is that its speed ''does not even relate to any frame of reference''. The speed of light in any medium depends solely on the [[electrical permittivity]] and [[magnetic permeability]] of that medium. (In fact, the speed of light is the [[reciprocal]] of the [[geometric mean]] of these two quantities.)
:Indeed, part of the problem with light is that its speed ''does not even relate to any frame of reference''. The speed of light in any medium depends solely on the [[electrical permittivity]] and [[magnetic permeability]] of that medium. (In fact, the speed of light is the [[reciprocal]] of the [[geometric mean]] of these two quantities.)
:Thus for c to change, the permittivity and permeability of vacuum must also have changed. And the only way to determine that is to examine previous records--and even ''that'' will fail if those records are not sufficiently precise.--[[User:TerryH|TerryH]]<sup>[[User talk:TerryH|Talk]]</sup> 14:41, 2 July 2007 (EDT)
:Thus for c to change, the permittivity and permeability of vacuum must also have changed. And the only way to determine that is to examine previous records--and even ''that'' will fail if those records are not sufficiently precise.--[[User:TerryH|TerryH]]<sup>[[User talk:TerryH|Talk]]</sup> 14:41, 2 July 2007 (EDT)
:I just thought I'd point out that changing C would have no effect on the observed amount of time it takes for light to reach us as long as the planck constant remains the same :) [[User:NRupert|NRupert]] 14:17, 5 June 2008 (EDT)
== White-hole Cosmology ==
== White-hole Cosmology ==