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ok , realative to other objects , but could we exisist for 1 second somhwere in time or space without this vector . perfect still


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Indeed this is correct. Photons can travel distances greater than the radius of the observable universe without interacting with matter. This has been true ever since the period know as "recombination" when electrons became bound to hydrogen and helium nuclei. Prior to that time there were lots of free electrons that could interact with light. ...


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The universe started with "big bang" is a slogan for "There was a time when the universe was hot and dense, and this time may be considered to be the start of the universe, and the start of time." The universe has (as far as we know) always been infinitely large. That's not certain, but we have no evidence contradicting it. The universe ...


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This answer to the question “Is the Hubble constant dependent on redshift?” gives the formula (a form of the Friedmann equation) for the Hubble parameter $H(z)$ as a function of redshift $z$: $$ H(z)^2 = H_0^2 \left[ (1+z)^4 \Omega_r + (1+z)^3 \Omega_M + (1+z)^2 \Omega_k + \Omega_\Lambda \right] $$ where the $\Omega$ terms are the fractional densities in ...


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