observational evidence: spectroscopic observations show that redshift affects all spectral lines uniformly, irrespective of the element. if redshift were caused by element-specific polarization effects, we would expect different elements to exhibit different amounts of shift based on their concentrations and atomic properties. this is not observed; instead, spectral lines from various elements are shifted by the same factor in distant astronomical objects. quantum mechanical considerations: the energy levels and transitions in atoms are governed by quantum mechanics. while classical models can provide some insights, they are insufficient for accurately predicting spectral shifts in terms of electrical polarization, particularly for complex atoms. physical limitations: the conditions required for the proposed effectextremely high atomic densities and significant polarizationare not present in the interstellar medium or in galaxies where we observe cosmological redshift. additionally, increased concentrations of elements can lead to other effects, such as collisional broadening, but these do not produce redshifts of the magnitude observed on cosmological scales. consistency across elements: applying the model to other elements would not result in uniform shifts unless the elements had similar concentrations and responded similarly to polarization, which is not the case. the uniformity of redshift across different elements supports the conclusion that the redshift is due to the expansion of space rather than local atomic effects.
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