The Universe Luminosity is the quantity of light radiated by a star. White light is the composition of all colors. In the elements, the discharge of energy can be displayed as light. Just by looking at the colors emitted, we can precisely identify the element. To understand the universe, the Doppler effect is one of the most important tools. The Doppler effect is a change in frequency due to a moving source. Jumping 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 when the rock is moving towards an individual. Additionally, the frequency will increase and the wave crests 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 part and the shortest wavelength is the purple part. If a body emits light and approaches someone, we would say that the radiation is blue-shifted. A red shift, on the other hand, occurs when the emitting object moves away or when a spectrum is shifted to longer wavelengths. Hubble measured that the farther a galaxy is from us, the greater the redshift, which is Hubble's law. In fact, galaxies could be moving away from us as fast as the speed of light. The farther away a galaxy is, the greater its speed. The universe is constantly expanding in all directions. There is a raisin cake model to explain this, thinking of the raisins as the galaxies and the cake as the space in between. The raisins are evenly distributed throughout the cake, just like the galaxies are in middle of paper......about what happened before the Big Bang. perhaps the universe was created from the collapse of a previous universe. Maybe black holes suck everything in, then when there's nothing left, maybe they push everything back. Maybe Heat Death's fluctuation model is correct and we live in a universe out there or maybe our universe supercooled and expanded. We don't know much. We don't even know if a quark is the smallest particle. Maybe the uncertainty principle keeps the universe separate. Black holes stretch the structure of time infinitely, carving a hole in space-time. What happens at the tear? Some say that at the edge of a black hole, some matter shrinks 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 understand why we are here.