# Can we measure without collapsing (too much) the wave function, according to decoherence theory?

According to decoherence theory, the collapse of the wave function is a continuous process due to interaction with environment. In a measure, there are interactions with photons (for example).

Can we measure with very few photons so that the wave function doesn't collapse [too much]?

• I'm not sure why you think this is specifically related to decoherence theory, but are you asking for weak measurement? – ACuriousMind Jun 16 '17 at 10:20
• @ACuriousMind: I don't think it is specifically related to decoherence theory, I ask a question about decoherence theory. If we replace "according to decoherence theory" by "according to Copenhagen interpretation", then the answer is no by definition. So for the question to be relevant, we need to assume an alternative to Copenhagen interpretation. Anyway, I did not have "weak measurement" in mind when I wrote this post, but it should be close to "measure with very few photons". – Sebastien Palcoux Jun 16 '17 at 13:16