Attenuation and redshift are two different phenomena that affect light in different ways.
Attenuation refers to the reduction in the intensity or amplitude of light as it propagates through a medium or material. It occurs due to various factors such as absorption, scattering, and reflection. When light interacts with particles or molecules in a medium, some of its energy can be absorbed or scattered in different directions, leading to a decrease in its amplitude. Attenuation is often associated with the loss of light energy as it travels through a medium, resulting in a reduction in the intensity or brightness of the light.
Redshift, on the other hand, is a phenomenon related to the wavelength of light. It occurs when light from a distant source is observed to have a longer wavelength (shifted towards the red end of the electromagnetic spectrum) compared to its original wavelength. Redshift is primarily caused by the Doppler effect, which is the apparent change in frequency or wavelength of a wave due to the relative motion between the source of the wave and the observer. In the context of cosmology, the observed redshift of light from distant galaxies is often attributed to the expansion of the universe. As space expands, the wavelengths of photons within that space also stretch, causing the observed redshift.
It's important to note that attenuation and redshift are distinct phenomena with different causes and effects on light. Attenuation leads to a decrease in the intensity or amplitude of light, while redshift causes a shift in the wavelength of light. The two phenomena are not directly related, and the presence of one does not necessarily imply the presence of the other.