The question of how the universe began and whether it started with light, darkness, or a mixture of both is a topic of scientific and philosophical speculation. Our current understanding of the universe's early moments is based on scientific theories such as the Big Bang theory.
According to the Big Bang theory, the universe originated from a singularity—an extremely hot and dense state—approximately 13.8 billion years ago. At this early stage, the universe was filled with high-energy particles and radiation, including photons (particles of light). However, the conditions during the first few moments of the universe were so extreme that the concept of light and darkness, as we understand them, might not have been applicable.
In the initial moments after the Big Bang, the universe was incredibly hot and dense, with matter and energy densely packed together. As the universe expanded and cooled, matter began to form, and photons could travel more freely through space. It took around 380,000 years for the universe to cool enough for atoms to form, allowing photons to escape and travel through space largely unimpeded. This event is known as the cosmic microwave background radiation, which is often considered the oldest light in the universe.
So, while the early universe was filled with a hot and dense mixture of matter, energy, and radiation, it is not accurate to describe it as purely light or darkness. The concept of light and darkness as we understand it emerged as the universe evolved and cooled over time.