Richard Feynman's quote about understanding quantum mechanics reflects the profound and intricate nature of the theory, rather than suggesting that we have no practical understanding or applications of it. While we have successfully harnessed the principles of quantum mechanics to develop technologies like computers, lasers, and atomic clocks, it is important to note that our understanding of quantum mechanics remains incomplete and continues to evolve.
Quantum mechanics describes the behavior of particles at the microscopic level, where the rules of classical physics break down. It introduces concepts such as superposition, entanglement, and wave-particle duality, which can be counterintuitive and challenging to comprehend fully. The mathematical framework of quantum mechanics allows us to make accurate predictions and develop practical applications, but the underlying conceptual understanding is still an active area of research.
The fact that we can build and use technologies based on quantum mechanics does not necessarily mean we fully understand all the fundamental aspects and philosophical implications of the theory. It is an ongoing process of exploration and refinement, with new insights and discoveries continually deepening our understanding of the subject.
Moreover, the technologies you mentioned, such as computers, lasers, and atomic clocks, are built upon the principles of quantum mechanics, but they do not necessarily require a comprehensive understanding of the theory at every level. Engineering and applied physics principles allow us to design and utilize these devices without needing to grasp the full depth of quantum mechanics.
In summary, the practical applications of quantum mechanics in various technologies demonstrate our ability to use and manipulate its principles effectively. However, the intricate nature of the theory and the ongoing research in the field remind us that our understanding of quantum mechanics is still a work in progress, and there is much more to learn and explore.