No, Einstein was not the founder of the modern theory of the universe.

The founder of the space navigation theory was the Russian Tsiolkovsky.

Constantin Tsiolkovsky (1857-1935) is the founder of modern astronautics. Known as the father of aerospace, he was the first to demonstrate the possibility of using rockets for interstellar transportation, manufacturing artificial earth satellites and low-Earth orbit stations, pointed out reasonable ways to develop aerospace and manufacture rockets, and found a solution for rocket and liquid engine structures. A series of important engineering technology solutions.

He has a famous saying: "The earth is the cradle of mankind, but mankind cannot be bound to the cradle forever."