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kuahji
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I was just thinking... perhaps this is a dumb question & the two are unrelated. But, they say the universe is roughly 14 billion years old. My question would be, relative to who?
the solar system is moving about 370 km/second with respect to CMBmiscellanyous said:Out of curiosity, how does this frame compare with the motion of the earth?
As I understand, there is a preferred frame of reference where the microwave background is isotropic and from this we conclude the expansion of the universe is also isotropic with respect to this frame. This privileged frame seems like trying to sneak Newton in the back door. Consider the privileged frame as belonging to one twin in the famous twins paradox of special relativity. When the twins are reunited, they will disagree on the how much time has elapsed and therefore disagree on the true age of the universe. So I am still unconvinced – it seems like special relativity must allow for a non-unique age for our universe.
marcus said:I don't understand why you bring up Special relativity. General relativity trumps special. We are working in GR here.
Suppose one twin is at rest with respect to CMB, and the other twin farts around and goes this way and that. then the time on the first twin's watch is right---corresponds more close to universe time. and the time on the giddy twin who was gadding about is just wrong. it doesn't correspond to the age of the universe we mean when we talk about the age of the universe.
However I think everybody recognizes that for GEN REL REASONS ...
miscellanyous said:I thank you for the info about the effects of gravity on time. I was not aware of this. I take your point is that it would not affect the age of the universe significantly. I am not sure if the same can be said about my objections too.
adriancombe said:...crazy amateur...
How do we know that the CMB speed is the "right" speed? In other words, what is is measured relative to, since all speed is relative?
The current estimated age of the universe is 13.8 billion years. This is determined through observations of the cosmic microwave background radiation, which is the leftover radiation from the Big Bang.
The theory of relativity, developed by Albert Einstein, is a set of two theories: special relativity and general relativity. Special relativity explains the relationship between space and time, while general relativity explains the behavior of gravity.
The theory of relativity has greatly impacted our understanding of the universe by providing a framework for understanding space, time, and gravity. It has helped explain phenomena such as the bending of light, the expansion of the universe, and the existence of black holes.
No, the age of the universe can only be estimated based on our current understanding and observations. As our technology and understanding of the universe improves, our estimation of the age may become more accurate, but it will never be known with 100% certainty.
There are several lines of evidence that support the Big Bang theory and the estimated age of the universe. These include the cosmic microwave background radiation, the abundance of light elements, the expansion of the universe, and the redshift of distant galaxies. Additionally, various astronomical observations and experiments have consistently supported these theories.