Final answer:
The student is referring to a hypothetical application of quantum entanglement and electron spin states to determine a spaceship's direction based on an entangled electron's measured spin. However, while entanglement ensures correlated states, no information can be transmitted faster than light as per the no-communication theorem in quantum mechanics.
Step-by-step explanation:
The scenario you're describing involves quantum entanglement and the electron spin state of entangled electrons. When particles such as electrons are entangled, their properties are linked in such a way that the state of one (regardless of the distance apart) instantly determines the state of the other. In quantum mechanics, an electron spin is an intrinsic form of angular momentum carried by electrons, and it can be in one of two states often referred to as "spin up" (ms = +1/2) or "spin down" (ms = -1/2).
According to the Stern-Gerlach Experiment, passing an electron through an external, nonuniform magnetic field causes the electron to exhibit two distinct states, related to its spin. This is because the magnetic moment of the electron behaves like a tiny magnet that aligns according to its spin state when subjected to the magnetic field. The experimental setup in your scenario suggests that if one entangled electron's spin state is measured on the spaceship, the other's state on Earth can be known instantly, indicating whether the spaceship turned left or right.
However, an essential consideration is that while entanglement ensures correlated states, the outcome of these measurements cannot be predicted in advance and cannot be used to transmit information faster than the speed of light due to the no-communication theorem in quantum mechanics. Hence, while it's true the observer on Earth would instantly know the state of the electron once the spaceship measures its entangled partner, they cannot know in advance which way the spaceship will turn and cannot use this information for faster-than-light communication.