Does the Cosmic Background Radiation Provide an Absolute Frame of Reference?

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Einstein's theory posits that there is no absolute frame of reference or 'absolute rest.' The Cosmic Microwave Background (CMB) radiation could suggest an absolute frame, as it appears isotropic to an object at rest relative to it. Current understanding indicates that we are moving relative to the CMB at approximately 800 km/sec in a specific direction. For the CMB to serve as an absolute frame, the laws of physics would need to exhibit unique properties within that frame. The discussion highlights the complexities of defining absolute rest in the context of modern physics.
shelanachium
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According to Einstein, there is no absolute frame of reference; no such thing as 'absolute rest'. But does not the Cosmic Background Radiation provide an absolute frame of reference? An object for which this radiation is totally isotropic is at absolute rest; I gather we move relative to it at some 800km/sec., and in a known direction.
 
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The CMB provides a cosmological frame of reference; for it to be 'absolute' in some sense would require the laws of physics in that frame to be special in some sense.

Garth
 

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