Even when part of the experience to abstract. The funny thing is that the abstract you can reach any experience. As was the case of the atom. This is a great phenomenon. Check out Neil deGrasse Tyson for additional information. Of matter and its phases.
But undoubtedly the object should be explained in an objective and not subjective. Because the goal is more subjective as regards the philosophy of physics. And the goal net to the philosophy of physics. Example: in the daily life of Achilles not need to beat the tortoise. Any man with all his strength and health can. This character 2007 Jose Orlando Melo Naranjo 28 Paul A: Tipler says that to describe the motion of a particle, we need the concepts of displacement, velocity and acceleration. Now let us illustrate a shift. If you want the redshift or (target galaxy) decrease in the frequencies of the electromagnetic emission light (radio waves) from the galaxy.
In particular, the lines of the visible spectrum they swing into the red end, which has given name to the displacement. The most natural interpretation of redshift, is to consider the Doppler effect, or as a result of the separation of galaxies to each other.