Stuart_Armstrong comments on To reduce astronomical waste: take your time, then go very fast

[Stuart_Armstrong]

We would not expect to see it coming in my model—the probes would be very small, the deceleration signature virtually undetectable.

[JoshuaZ]

the probes would be very small, the deceleration signature virtually undetectable.

Sure, but if they start doing stuff on any large scale on another solar system, that should be noticeable. We don’t see any evidence that star’s energy is being harvested.