Carlo Rovelli suggests that the discomfort with quantum mechanics as a fundamental description of nature, often referred to as the measurement problem, may stem from an incorrect notion: the idea of an observer-independent state of a system or values of physical quantities. He reformulates the interpretation of quantum mechanics as deriving the formalism from a set of simple physical postulates and proposes a reformulation in terms of information theory. Rovelli argues that all systems are equivalent, there is no observer-observed distinction, and the theory describes only the information systems have about each other. He emphasizes that this approach makes quantum mechanics more understandable and complete. In the paper, Rovelli discusses the problem of interpreting quantum mechanics, comparing it to the historical critique of Lorentz transformations in special relativity. He suggests that the discomfort with quantum mechanics may be due to an incorrect notion, similar to the concept of absolute time in special relativity. By abandoning the notion of an observer-independent state, quantum mechanics becomes more coherent. Rovelli analyzes the measurement process from the perspectives of two different observers, leading to the conclusion that different observers can give different accounts of the same sequence of events. He refutes various objections to this main observation, including the idea that quantum states are observer-dependent and that the physical content of the theory lies in the outcomes of measurements. He proposes that quantum mechanics is a theory about the states of systems and values of physical quantities relative to other systems, making all physical variables relational. This relational approach suggests that quantum mechanics provides a complete and self-consistent description of the physical world, appropriate to our current level of experimental observations. Rovelli concludes that the notion of a universal, observer-independent description of the state of the world is physically untenable, and that quantum mechanics indicates that reality is fully relational.Carlo Rovelli suggests that the discomfort with quantum mechanics as a fundamental description of nature, often referred to as the measurement problem, may stem from an incorrect notion: the idea of an observer-independent state of a system or values of physical quantities. He reformulates the interpretation of quantum mechanics as deriving the formalism from a set of simple physical postulates and proposes a reformulation in terms of information theory. Rovelli argues that all systems are equivalent, there is no observer-observed distinction, and the theory describes only the information systems have about each other. He emphasizes that this approach makes quantum mechanics more understandable and complete. In the paper, Rovelli discusses the problem of interpreting quantum mechanics, comparing it to the historical critique of Lorentz transformations in special relativity. He suggests that the discomfort with quantum mechanics may be due to an incorrect notion, similar to the concept of absolute time in special relativity. By abandoning the notion of an observer-independent state, quantum mechanics becomes more coherent. Rovelli analyzes the measurement process from the perspectives of two different observers, leading to the conclusion that different observers can give different accounts of the same sequence of events. He refutes various objections to this main observation, including the idea that quantum states are observer-dependent and that the physical content of the theory lies in the outcomes of measurements. He proposes that quantum mechanics is a theory about the states of systems and values of physical quantities relative to other systems, making all physical variables relational. This relational approach suggests that quantum mechanics provides a complete and self-consistent description of the physical world, appropriate to our current level of experimental observations. Rovelli concludes that the notion of a universal, observer-independent description of the state of the world is physically untenable, and that quantum mechanics indicates that reality is fully relational.