LSAT (Law School Admission Test)Reading ComprehensionMedium
Passage: "The concept of 'quantum entanglement' describes a phenomenon where two or more particles become linked in such a way that they share the same quantum state, regardless of the distance separating them. When one entangled particle is measured, its properties instantly influence the properties of the other, even if they are light-years apart. This 'spooky action at a distance,' as Einstein famously called it, challenges classical notions of locality and causality. While entanglement has no known classical analogue, it is a well-confirmed phenomenon with profound implications for quantum computing and cryptography. The instantaneous correlation does not, however, allow for faster-than-light communication, as no information can be transmitted in this manner; the measurement outcome of one particle is inherently random and unpredictable, so no predetermined signal can be sent. The utility lies in the shared randomness and certainty of correlation once measurements are made." Based on the passage, why is faster-than-light communication not possible using quantum entanglement?
- AThe entangled particles lose their quantum state coherence over long distances, preventing instantaneous correlation.
- BFaster-than-light communication is only possible with particles that are not entangled and can be independently manipulated.
- CThe act of measurement on one particle destroys the entanglement, making further information transfer impossible.
- DThe outcome of measuring an entangled particle is fundamentally random, meaning no controlled message can be sent.
Show answer & explanationAnswer & explanation
Correct answer: D. The outcome of measuring an entangled particle is fundamentally random, meaning no controlled message can be sent.
The passage explicitly states: 'The instantaneous correlation does not, however, allow for faster-than-light communication, as no information can be transmitted in this manner; the measurement outcome of one particle is inherently random and unpredictable, so no predetermined signal can be sent.' This directly explains why FTL communication is impossible.
Why the other options are wrong
- A. The passage states they 'share the same quantum state, regardless of the distance separating them,' contradicting this option.
- B. The passage focuses on why entanglement *doesn't* allow FTL communication, not on other theoretical methods.
- C. While measurement does affect the quantum state, the passage's primary reason for no FTL communication is the randomness of the outcome, not the destruction of entanglement itself as the barrier.
Stated Reason/Cause
Identifying the explicit reason or cause provided in the text for a particular phenomenon, event, or limitation.
- Look for causal language like 'because,' 'as,' 'due to,' 'since,' or 'the reason is.'
- Ensure the chosen reason is directly stated in the passage, not inferred or assumed.
- Distinguish between a primary reason and secondary or supporting details.
Memory trick: Reason Reveals the 'Why' Behind the Effect.