is it possible to set up a double slit device/detector with another double split device/detector behind only one of the slits?QTT, however, can take back-action into account. The catch is that, to apply QTT, you need to have nearly complete knowledge about the behavior of the system you’re observing. Normally, an observation of a quantum system overlooks a lot of potentially available information: Some emitted photons get lost in their environment, say. But if pretty much everything is measured and known about the system — including the random consequences of the back-action — then you can build feedback into the measurement apparatus that will make continuous adjustments to compensate for the back-action. It’s equivalent to adjusting the telescope’s orientation to keep the planet in the center.
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They must keep track of effects that go backwards in time.
See Wheeler’s delayed choice experiment:
https://en.wikipedia.org/wiki/Wheeler%27s_delayed-choice_experiment
Kinda makes sense. If you have a tightly bound system of the very smallest things, using any of those smallest things to provide a “measurement” is going mess with the alignment of the entire system. Hence the “collapse of the wave function.”
is it possible to set up a double slit device/detector with another double split device/detector behind only one of the slits?