Quantum information, like any other form of information, is not inherently relative. It is an objective concept that describes the state, properties, and behavior of quantum systems.
However, in the context of quantum mechanics, the information we can extract from a quantum system is often described in a probabilistic manner due to the inherent uncertainty associated with quantum measurements. The act of measuring a quantum system disturbs its state, and the outcome of a measurement is typically described in terms of probabilities.
Furthermore, quantum mechanics incorporates the principle of superposition, which allows quantum systems to exist in multiple states simultaneously. The information about the state of a quantum system is encoded in a complex mathematical object called a quantum state, typically represented as a wave function or density matrix. The quantum state can be in a superposition of multiple states, and the relative amplitudes of these states determine the probabilities of measurement outcomes.
Additionally, quantum entanglement introduces a form of correlation between different parts of a quantum system, where the information about one part is inherently related to the information about another part. This correlation is often described as non-local, meaning that the information about one part cannot be fully understood without considering the information about the other part. However, these correlations are not relative in the sense of being dependent on an observer's frame of reference or perspective.
In summary, while quantum information is not relative in the sense of being observer-dependent, the probabilistic nature of quantum measurements and the existence of superposition and entanglement can introduce complexities in how we describe and interpret quantum information.