Determining what happened in the universe before the formation of quarks is a challenging task for scientists due to a few reasons:
Cosmic Inaccessibility: The conditions of the early universe, particularly during the time before quark formation, were extremely hot and dense. At such high energies, the fundamental forces of nature are expected to have been unified. However, these extreme conditions make it difficult to directly probe or observe what occurred during that epoch. The energy scales required to investigate these early stages of the universe are currently beyond the reach of our experimental capabilities.
Limited Observational Evidence: The earliest moments of the universe are shrouded in what is known as the "cosmic microwave background radiation" (CMB). This radiation is the remnants of the hot, dense phase of the universe that existed about 380,000 years after the Big Bang. While the CMB provides valuable insights into the universe's early evolution, it does not directly reveal the specific details of what transpired before the formation of quarks.
Theoretical Uncertainties: Understanding the behavior of matter and the fundamental forces at the incredibly high energies of the early universe requires a comprehensive theory that unifies quantum mechanics and general relativity. Currently, such a theory, often referred to as a "theory of everything" or a "quantum theory of gravity," remains elusive. Without a complete understanding of this regime, it is challenging to precisely describe the events before quark formation.
Despite these limitations, scientists are actively engaged in developing theories and models to explain the early universe, such as inflationary cosmology and various proposals for quantum gravity. These theories provide insights and predictions about the universe's behavior during its early stages, but their validation and verification rely on future experimental and observational advancements that may uncover further evidence or clues about the period before quark formation.