The reference frame

Concepts about reference frame.

The reference frame is the position from where the objects are observed. All observers that are on some reference think they are standing still, because they do not know their own motion.

The driver thinks he is at rest and sees the railroad station cross over him as it was at speed opposite to the train’s –v. Actually, he just know he is moving due to the train’s vibration and also to the sound of the tires.

In this figure, the train is at rest. Thus, the driver and the observer both seated on the station’s seat are on the same reference frame. It means that both observers are at the same speed. Thus, we can conclude that the relative motion (v) between them is responsible for the distinction of the truth observed between them.
So, we conclude that the truth of observers is always related to their own reference frame. We will always be moving regardless of the reference, because, we are always on some galaxy being that all of them have been acquiring expansion speed since the beginning (initial explosion).

Absolute reference frame

As we already know that truth is relative, we can still having the same question: There is an absolute truth? If there was an absolute truth it could just be detected by an observer who was really at rest; therefore, it is easy to conclude that he could not be on the reference frame of any galaxy, so that all galaxies are moving. Thus, we can deduce that such reference frame can just exist where all motions of universe took place that would be associated to the reference of Big Bang.
The observer on the reference of Big Bang due to it is completely standing still, would not be influenced by motions that distort the absolute truth. Thus, it is an outstanding reference frame, being that the observer who is on it sees the absolute truth of all motions in the universe, including the motions of photons that are influenced by motions of their sources. Actually, such observer is the only one that knows such motions, because the observers on galaxies do not know their expansion speeds acquired on Big Bang due to they think they are at rest. Therefore, they will never know the influence that such speeds exert on photons emitted by sources that they are on.
Finally, we can say that the reference frame of Big Bang, which is associated to the place or initial singularity, is the absolute reference frame.