Advanced Civilizations in Universes and Multiverses
Many estimates have been made of the number of extraterrestrial civilizations using approaches such as the Drake equation. These estimates vary considerably according to the many assumptions made, and range from millions to zero (for example, \citealt*{Drake_1992}; \citealt{Wilson_2001}; \citealt{Forgan_2009}; \citealt*{Frank_2016}; \citealt{Sandberg_2018}). Considerations include whether the estimates apply to the Milky Way or the observable universe, include past and future civilizations, and whether communication constraints such as the speed of light are considered. The likelihood of the evolution of advanced Kardashev civilizations or entities should be higher if the entire universe rather than just the observable universe is included. Estimates of the size of the entire universe relative to the observable universe are also uncertain ranging from around 251 times greater (\citealt{Vardanyan_2011}) to very many orders of magnitude greater (\citealt{Guth_1997}). Other things being equal, the likelihood of emergence of an advanced entity should be greater in a large than a small universe.
This reasoning can be extended to the emergence of advanced entities in a multiverse consisting of many individual universes. Multiverse theories include the idea that our universe is infinite with every possibility realised in some part of it, eternal inflation with an infinite number of pocket universes, and the many worlds interpretation of quantum mechanics (see \citealt{Tegmark_2003}; \citealt{Page_2008}). Another idea is that black holes within universes may spawn offspring universes (\citealt{Smolin_1997}; \citealt{Smolin_2004}; \citealt{Vaas_2003}). The multiverse is a substantial area for investigation and analysis in theology and philosophy as well as in physics. The possibility that God may or may not have created the multiverse has been discussed (\citealt{Page_2008}; \citealt{Chan_2015}), as has the relevance of the multiverse to the problem of evil (\citealt{Megill_2011}; \citealt{Kraay_2013}; \citealt{Ignatova_2019}; \citealt{Rogers_2020} ). Multiverse ideas have also been used in discussion of the nature or existence of God involving modal realism and possible worlds (\citealt{Kraay_2010}) and in proofs of the existence of God (\citealt{Spitzer_2019}).
The likelihood of an advanced entity capable of creating and controlling new universes arising in an infinitely large multiverse (including an infinitely large universe) should be greater than in a single universe of finite size. In this context, appeal can also be made to the plenitude principle that no genuine potentiality of being can remain unfulfilled (\citealt{Lovejoy_1936a}; \citealt{Kane_1976}; \citealt{Kragh_2019}). It could thus be inevitable that such an advanced entity will evolve somewhere at some time in an eternal existence of a potentially infinite number of universes, even if the probability of any given universe generating advanced entities is low.
Emergence of God in a Multiverse
The idea that an advanced entity or civilization from another universe created our own universe was proposed previously (for example, \citealt{Harrison_1995}; \citealt{Gribbin_2010}; \citealt{Vidal_2015}). Many science fiction stories also portray entities with godlike properties (see examples in Appendix 1). Some solutions of the Fermi paradox envisage that extraterrestrials are responsible for manufacturing our world as we see it. For example, the zoo hypothesis proposes that Earth is a zoo or reserve created by extraterrestrials who are secretly observing us (\citealt{Ball_1973}). The planetarium hypothesis proposes that we are living in a simulation created by extraterrestrials (\citealt{Baxter_2000}). This latter hypothesis considers that the simulation is created by a Type III Kardashev civilization possessing energy on the scale of its own galaxy. Although all these ideas may envisage a creator of our universe or world, it is not generally envisaged that this creator is God. The creator is depicted more as an advanced entity representing an alternative to God as a creator.
The idea considered in this essay is that an advanced entity of sufficient greatness has emerged naturally and inevitably from a potentially infinite number of universes, as in a multiverse, and that this entity is God. Emphasis is on the inevitability of this happening given the power of natural and technological evolution, the potential infinity of universes, and with appeal also to the plenitude principle. Many ontological proofs of the existence of God consider God to be a supremely or maximally great or perfect being (see for example, \citealt{Oppy_2018b}). For example, the proof of St Anselm considers God as a being “than which nothing greater can be thought”, where greatness can be in qualities such as omnipotence and omniscience. So, appealing again to the unlimited possibilities for evolution in a potentially infinite number of universes and the plenitude principle, this maximal greatness on a scale such as an extended Karadashev scale could also be inevitable.
A distinction can be drawn between the emergence of an advanced entity on a Kardashev scale capable of creating worlds or universes and a maximally great entity which is God. For example, advanced extraterrestrials, as in the zoo and planetarium hypotheses may deceive us, but they would not have the maximal greatness of God. The focus in this essay is that the naturally emerging God tends towards the entity of maximal greatness rather than towards a highly advanced entity arising in our own or other universe that we may be deceived into believing is God. The naturally emerging God would have the properties of God and thus truly be God, but would not be a supernatural being.
Maximal greatness may be set by the physical properties and scientific laws of the multiverse and universes involved. Unlimited possibilities may however imply a multitude of gods at various stages of advancement. This could be in line with religions which have many gods. Perhaps one way to generate a single God of maximal greatness would be to imagine a process of merging within this multitude of gods. Another way might involve competition and natural selection between gods. Another might involve collaboration and agreement between gods. Such processes would need to be constrained by whatever physical laws could be operational within the multiverse in relation to the feasibility of interaction between universes and between the gods they contain. One speculation for communication between universes is that this might be via wormholes (\citealt{Blonde_2016}).
Religions could arrive at a conception of this God not only through revelation and reason, but also potentially through scientific investigation given that this God has emerged naturally. But could the hypothesis of a naturally emerging God be tested scientifically? The hypothesis of extraterrestrial civilizations is consistent with current scientific knowledge even if there is no direct evidence that such civilizations exist. The hypothesis of a naturally emerging God may require evidence of both multiple universes and that any advanced entities within these be at the required maximally advanced position on a Kardashev type scale. Multiverse theories do give testable predictions (\citealt{Page_2006}; \citealt{Tegmark_2003}). However, the generation of testable predictions for a natural God emerging out of the multiverse does not look feasible at present. Perhaps the best approach to evidence and testing now would be to focus on the scientific analysis of the Fermi paradox and to try to detect direct evidence of revelation by advanced entities. One explanation of the Fermi paradox, the interdict hypothesis, considers that a “galactic club” of advanced civilizations might have decided to leave life-bearing planets like ours undisturbed (\citealt{Fogg_1987}; \citealt{Webb_2002}). If the revelations by a naturally emerging God were restricted in some similar way, this could frustrate the search for scientific evidence.