About Sim Worlds

Some questions about life in a sim world:

• Is it possible for a sim to realize that he is living in a virtual world [1]? Could he do that by verifying that the physics laws of his world do allow a mathematically elegant or coherent formulation ?


• Is it possible for a sim to realize that his world doesn’t conform with the anthropic principle¹ [2] ?


• Is it possible to build a virtual world inhabited by intelligent sims, who perceive their world in such a way that they can model it by a physical theory completely different from ours ?

[1] Hans Moravec, Pigs in Cyberspace, 1992, http://www.cni.org/pub/LITA/Think/Moravec.html
[2] John Barrow and Frank J. Tipler, The Anthropic Cosmological Principle, Oxford University Press, Oxford, 1988.

¹ The Anthropic Principle was proposed in Poland in 1973, during a special two-week series of synopsia commemorating Copernicus’s 500th birthday. It was proposed by Brandon Carter, who, on Copernicus’s birthday, had the audacity to proclaim that humanity did indeed hold a special place in the Universe, an assertion that is the exact opposite of Copernicus’s now universally accepted theory. In his contribution "Large Number Coincidences and the Anthropic Principle in Cosmology" Carter remarks: "Although our situation is not necessarily central, it is inevitably privileged to some extent" (IAUS 63 (1974) 291).
Proponents of the anthropic principle suggest that we live in a fine-tuned universe, i.e. a universe that appears to be "fine-tuned" to allow the existence of life as we know it. If any of the basic physical constants were different, then life as we know it would not be possible. Papers have been written arguing that the anthropic principle would explain the physical constants such as the fine structure constant, the number of dimensions in the universe, and the (an arbitrary constant in Einstein’s equations of general relativity theory) cosmological constant. The two main forms of the anthropic principle are [2]:
Weak anthropic principle (WAP): "The observed values of all physical and cosmological quantities are not equally probable but they take on values restricted by the requirement that there exist sites where carbon-based life can evolve and by the requirements that the Universe be old enough for it to have already done so."
Strong anthropic principle (SAP): "The Universe must have those properties which allow life to develop within it at some stage in its history."