The UniverseBrightness is the amount of light radiated by a star. White light is the composition of all colors. In the elements, the discharge of energy can be visualized as light. Only by observing the colors that are discharged is it possible to precisely identify the element. To understand the universe, the Doppler effect is one of the most important tools. The Doppler effect is a frequency shift due to a moving source. Skipping a rock across water would be an example of this effect. The circles would be off center because the rock is a moving source. The wavelength is shorter as the rock gets closer to an individual. Furthermore, the frequency will increase and the crests of the waves will shorten. As the source moves away from an individual, the wavelength increases and the frequency decreases. This principle is identical to light. In a rainbow, the longest wavelength is the red portion and the shortest wavelength is the violet portion. If a body emits light and comes close to someone, we would say that the radiation is blue-shifted. A redshift, on the other hand, occurs when the emitting object moves away or when a spectrum is shifted to longer wavelengths. Hubble measured that the further a galaxy is from us, the greater the redshift, which is Hubble's law. In fact, galaxies may be moving away from us at the same speed as light. The greater the distance to a galaxy, the greater its speed. The universe is continually expanding in all directions. There is a raisin cake model to explain this, considering the raisins as the galaxies and the cake as the space in between. The raisins are evenly distributed throughout the cake, just as the galaxies are scattered... in the center of the card... regarding what happened before the Big Bang. perhaps the universe was created by the collapse of a previous universe. Maybe black holes suck everything in and then, when there's nothing left, maybe they push everything out. Maybe the Heat Death fluctuation model is correct and we live in a universe out there or maybe our universe is supercooled and expanded. We don't know much. We don't even know if a quark is the smallest particle. Perhaps the uncertainty principle keeps the universe separate. Black holes stretch the fabric of time infinitely, tearing a hole in space-time. What happens to the tear? Some say that near a black hole some of the matter decreases because it loses energy through its jets and tears, creating small bubbles. The little bubbles could be the universes. With science we will never be able to answer why we are here.