Answer:
There are many theories of what existed before the Universe was born at the Big Bang. To be more exact, the Big Bang is a theory as well. Some scientists think that before the Big Bang there might be an older Universe that died out before the Big Bang started. Others think that before the Big Bang, there was just Ultra hot, dense material that can create the stars. Of course, we are not fully confident about what existed before the Big Bang, or if the Big Bang even occurred, as they are all just theories.
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