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维基百科的介绍：Constructor theory – Wikipedia
Constructor theory is a proposal for a new mode of explanation in fundamental physics in the language of ergodic theory, first sketched out by David Deutsch, a quantum physicist at the University of Oxford, in 2012. Constructor theory expresses physical laws exclusively in terms of which physical transformations, or tasks, are possible versus which are impossible, and why. By allowing such counterfactual statements into fundamental physics, it allows new physical laws to be expressed, such as the constructor theory of information.
The fundamental elements of the theory are tasks—the abstract specifications of transformations as input-output pairs of attributes. A task is impossible if there is a law of physics that forbids its being performed with arbitrarily high accuracy, and possible otherwise. When it is possible, a constructor for it can be built, again with arbitrary accuracy and reliability. A constructor is an entity that can cause the task to occur while retaining the ability to cause it again. Examples of constructors include a heat engine (a thermodynamic constructor), a catalyst (a chemical constructor) or a computer program controlling an automated factory (an example of a programmable constructor).
The theory was developed by physicists David Deutsch and Chiara Marletto. It draws together ideas from diverse areas including thermodynamics, statistical mechanics, information theory, and quantum computation.
According to Deutsch, current theories of physics-based on quantum mechanics do not adequately explain why some transformations between states of being are possible and some are not. For example, a drop of dye can dissolve in water but thermodynamics shows that the reverse transformation, of the dye clumping back together, is effectively impossible. We do not know at a quantum level why this should be so. Constructor theory provides an explanatory framework built on the transformations themselves, rather than the components.
Information has the property that a given statement might have said something else, and one of these alternatives would not be true. The untrue alternative is said to be “counterfactual“. Conventional physical theories do not model such counterfactuals. However, the link between information and such physical ideas as the entropy in a thermodynamic system is so strong that they are sometimes identified. For example, the area of a black hole‘s event horizon is a measure both of the hole’s entropy and of the information that it contains, as per the Bekenstein bound. Constructor theory is an attempt to bridge this gap, providing a physical model which can express counterfactuals, thus allowing the laws of information and computation to be viewed as laws of physics.