Yes, the expansion itself redshifts photons. Basically, the wavelength of photons is increased by the same factor as the distances between galaxies is increased with expansion.edoarad said:does the expansion itself redshifts photons (if so, does the expansion affect the photon in his frame of referance?) or is it because the distant object that emits them is seemingly moving away from us (in cases where the expansion is much more dominant of course)? The latter doesn't makes much sense to me because the object isn't really moving as fast as he seems.
The expansion of the universe causes redshift through a phenomenon known as cosmological redshift. As the universe expands, the light from distant galaxies and objects in space also stretches, causing their wavelengths to appear longer and therefore shift towards the red end of the electromagnetic spectrum.
No, redshift can also be caused by other factors such as the Doppler effect, which occurs when an object is moving away from an observer. However, in the context of the universe, redshift is primarily caused by the expansion of space.
The rate of expansion, also known as the Hubble constant, directly affects the amount of redshift observed in an object. A higher Hubble constant results in a higher rate of expansion and therefore a larger redshift, while a lower Hubble constant leads to a smaller redshift.
Yes, redshift affects all types of light, including visible light, radio waves, and X-rays, equally. The amount of redshift observed may vary depending on the wavelength of the light, but the effect is still present in all types of electromagnetic radiation.
The observation of redshift in distant galaxies and objects is one of the key pieces of evidence for the expansion of the universe. The amount of redshift observed is directly proportional to the distance of the object, indicating that the farther an object is, the faster it is moving away due to the expansion of the universe.