From Dave Holtum, Bath, UK
Tim Rafferty’s claim that simulators would only have to “simulate our ability to observe the universe” is often called lazy evaluation, but it faces a number of hurdles (Letters, 3 January).
Objects cannot simply “pop” into existence: their current state requires a massive, recursive calculation of their entire history, effectively forcing a full-scale simulation. If the simulator didn’t do this, it would be obvious to us that we were living in a simulation.
Quantum mechanics also complicates things. Superposition requires tracking all possible states simultaneously, while entanglement demands global overhead. Rather than saving power, these quantum features are computationally more taxing than a fixed, classical reality, making “lazy” shortcuts scientifically improbable.
