Answer:
The Big Bang Theory is the most common and most recognized model of the origin of our universe.
The second similar model is the model of the expanding Universe. Now it is known for certain that galaxies and other cosmic objects are moving away from each other, which means that the Universe is expanding. In the 20th century, there were many alternative theories of the origin of the universe. One of the most popular was the model of the stationary Universe, for which Einstein advocated. According to this model, the Universe does not expand, but is in a stationary state due to some kind of holding force.
A modern study of the evolution of the Universe is impossible without reconciling it with quantum theory. So, for example, within the framework of string theory (string theory is based on the hypothesis that all elementary particles and their fundamental interactions arise as a result of vibrations and interactions of ultramicroscopic quantum strings), a model of the multiple Universe is assumed.
Step-by-step explanation: