yes, light that appears to be absorbed before it is emitted. no idea what that mechanism is, it seems like a tinker toy novelty, what use is that? they reversed the causal sequence of emission but unless that bounces off something it doesn't tell you the future. but then it unbounces, doesn't it? seems like a paradox you can't do anything with it. how about we think about how we can capture energy from the future and spend it today. now that is useful.