The Turing Guide

442 | 40 TURING’S mENTOR, mAX NEwmAN what a fluke! I conclude with some reflections about this very unusual history. As a result ...

PART VIII Finale ...

...

CHAPTER 41 Is the whole universe a computer? jack copeland, mark sprevak, and oron shagrir T he theory that the whole universe i ...

446 | 41 IS THE wHOlE UNIVERSE A COmPUTER? figure 41.1 Is the universe a computer? The Pillars of Creation, in the distant Eagle ...

COPElAND, SPREVAk & SHAGRIR | 447 asynchronous computers (computers with no central ‘clock’ coordinating the processing), na ...

448 | 41 IS THE wHOlE UNIVERSE A COmPUTER? computer is itself a computer: by performing steps that the idealized human computer ...

COPElAND, SPREVAk & SHAGRIR | 449 of the stored-program concept, in a 1936 patent application, it was not until the 1960s th ...

450 | 41 IS THE wHOlE UNIVERSE A COmPUTER? mathematical equation), CAs can also solve such problems. The problem is encoded in t ...

COPElAND, SPREVAk & SHAGRIR | 451 characters: they maintain cohesion, move, reproduce, and interact with one another. Their ...

452 | 41 IS THE wHOlE UNIVERSE A COmPUTER? what the CA’s grid is in fact made of is far from clear, as we shall see below. This ...

COPElAND, SPREVAk & SHAGRIR | 453 colliders are never likely to be able to explore events at the Planck scale. In 2014, Crai ...

454 | 41 IS THE wHOlE UNIVERSE A COmPUTER? simply to describe the universe’s computation; physics must remain silent about the i ...

COPElAND, SPREVAk & SHAGRIR | 455 Is the behaviour of the lamp still computable? Yes, it is. Turing showed that π is what he ...

456 | 41 IS THE wHOlE UNIVERSE A COmPUTER? model of the human computer, also in 1936, which Turing quickly proved to be equivale ...

COPElAND, SPREVAk & SHAGRIR | 457 a computable universe; and the uncomputable lamp example—where the rule that determines wh ...

458 | 41 IS THE wHOlE UNIVERSE A COmPUTER? Russell emphasized that although a human runner’s accelerating in this way is ‘medica ...

COPElAND, SPREVAk & SHAGRIR | 459 However, the fact that the ATM is a logical possibility doesn’t mean that it could actuall ...

460 | 41 IS THE wHOlE UNIVERSE A COmPUTER? Németi’s system consists of two parts, one part being a standard Turing machine S, lo ...

COPElAND, SPREVAk & SHAGRIR | 461 without printing ‘#’. By time t, therefore, O knows whether or not a signal has been emitt ...