Talk:Quantum-locking

This is a very clever reference to quantum mechanics - the strange physics of the quantum scale - light can both be a wave and a particle, a wave when you are not looking, a particle when observed. Also in quantum mechanics the uncertainty principle states that you can never know both a particles speed and location at the same time. If you know a particles speed you cannot pinpoint its location, if you know its location, you cannot measure its speed. This may sound impossible but many experiments have proven this.

The point I am making is that the writers have made a clever reference. Wormulon 13:14, 7 July 2009 (UTC)

The weeping angles act in a similar way to the behavoir of light in the real world. Wormulon 13:18, 7 July 2009 (UTC)

This show also throws the watcher into the mystical world of Quantum mechanics, albeit, just momentarily. The quantum locking of the Angels is exactly how a particle/wave reacts in the world of QM. Unseen, it does what it pleases, while being watched, it is solid. Intersting stuff.

86.176.73.20 08:55, 23 August 2009 (UTC)

The problem with this is that "quantum locking" implicitly assumes (the active version of) the Copenhagen interpretation, while almost every other reference to quantum physics on the show implicitly assumes the Everett-Wheeler ("Many Worlds") interpretation.

It's a bit hard to explain the difference, but I'll try, by reference to Schroedinger's Cat.

• In CI, systems evolve (according to the Schroedinger equation) whenever they're not being observed, which means they eventually end up in a superposition of states--the cat in the box is both alive and dead at the same time. But observation somehow causes the waveform of the system to collapse into a single state--the cat in the box is either alive or dead as soon as you look at it. The biggest problem with CI is the "Observer Paradox"--what exactly counts as an observation, and how could whatever-it-is-that-counts affect the system?
• In MWI, systems evolve continuously, and never collapse. The cat is still both alive and dead, and you are both in a state of having seen a live cat and having seen a dead one. Because these states can only interact through quantum interference phenomena, they can effectively be treated as separate universes in a multiverse, hence the "Many Worlds" name. There is no Observer Paradox in MWI, because observation doesn't do anything.

Many episodes refer to an MWI-style multiverse (most obviously Turn Left), which implies that there is really nothing special about observation, which would make "quantum locking" nonsense.

Of course Doctor Who is not hard SF, so they don't have to be consistent about this. Besides, it's always possible that quantum mechanics is just an approximation to a "truer" underlying reality, and that both interpretations are in some way "correct" in different situations, once you reduce QM to the deeper theory. --Falcotron 09:51, April 25, 2010 (UTC)