The question you're asking touches on the philosophical interpretation of quantum mechanics and the nature of reality. There are different interpretations and viewpoints regarding this topic, and no single answer has been widely accepted.
One interpretation is that of the Copenhagen interpretation, which suggests that the act of observation or measurement causes the collapse of the quantum wave function, leading to a definite outcome. According to this view, before any observation occurred, the quantum system existed in a superposition of all possible states, including wave-like behavior. However, the application of observation or measurement collapses the wave function and determines a particular outcome.
Another interpretation is the Many-Worlds interpretation, which posits that all possible outcomes of a quantum event actually occur, but in different branches of the universe. In this view, the universe before observation would have branched into multiple parallel universes, each representing a different outcome of the measurement.
It's important to note that these interpretations are still the subject of ongoing debate and speculation within the scientific community. The nature of reality and the behavior of quantum systems in the absence of observation are profound questions that continue to be explored and studied.
Ultimately, the answer to what the universe was like before observation is uncertain and may depend on the interpretation one adopts.