Naked Universe of Ana

If you look at a photon does it change its trajectory?

Added 2025-07-29 11:56:30 +0000 UTC

Sounds like you are some big D boss influencing a photon.
But what really happens when you "look" at a photon?
To see it the photon has to hit your eye and disappear, being absorbed by the molecules in your retina. Basically you just "ate" it with your eye.

But where does the myth come from?
From quantum physics and the famous double slit experiment.
No this is not about double penetration. It is about the Young experiment.
There the result really changes if you measure which slit the photon passed through.

But observation in quantum physics = interaction.
Why? Because everything is so tiny you cannot even fart without consequences. Everything is fragile because particles are so small.
A photon is also a particle, well sometimes :)
The detector exchanges energy with the photon and breaks its fragile state of superposition (where it was "both here and there" at the same time) and the photon behaves like a particle instead of a wave.

Any way to know the state of a particle requires touching it, colliding with it, reflecting it, absorbing it.
This is what "influence of observation" means, not magic, just the law of very small scales.