The observer effect is a real thing, and even has interesting effects in quantum mechanics, e.g. the quantum zeno effect https://en.wikipedia.org/wiki/Quantum_Zeno_effect
Yet the observer effect is not the reason why we can't know an object's position and velocity at the same time. There are two ways we can see that this supposed explanation is a red herring:
- We don't need to interact with (e.g. 'bounce a photon off') a quantum system in order to observe it ( https://en.wikipedia.org/wiki/Interaction-free_measurement ). I particularly like the "quantum bomb detector" ( https://en.wikipedia.org/wiki/Elitzur%E2%80%93Vaidman_bomb_t... ), which can tells us whether a photon detector connected to a bomb is working or not, without hitting it with a photon and hence triggering the bomb (50% of the time, at least).
- The actual reason, the uncertainty principle ( https://en.wikipedia.org/wiki/Uncertainty_principle ), doesn't require any notion of observation at all, let alone interaction. It's a simple property of waves (the relationship between duration and frequency). 3blue1brown did a nice video on this https://www.youtube.com/watch?v=MBnnXbOM5S4
The observer effect is a real thing, and even has interesting effects in quantum mechanics, e.g. the quantum zeno effect https://en.wikipedia.org/wiki/Quantum_Zeno_effect
Yet the observer effect is not the reason why we can't know an object's position and velocity at the same time. There are two ways we can see that this supposed explanation is a red herring:
- We don't need to interact with (e.g. 'bounce a photon off') a quantum system in order to observe it ( https://en.wikipedia.org/wiki/Interaction-free_measurement ). I particularly like the "quantum bomb detector" ( https://en.wikipedia.org/wiki/Elitzur%E2%80%93Vaidman_bomb_t... ), which can tells us whether a photon detector connected to a bomb is working or not, without hitting it with a photon and hence triggering the bomb (50% of the time, at least).
- The actual reason, the uncertainty principle ( https://en.wikipedia.org/wiki/Uncertainty_principle ), doesn't require any notion of observation at all, let alone interaction. It's a simple property of waves (the relationship between duration and frequency). 3blue1brown did a nice video on this https://www.youtube.com/watch?v=MBnnXbOM5S4