Robin Hanson. According to it, the Fermi-paradox can be explained by the existence of a barrier that usually prevents the dead matter to become living and/or intelligent and albeit we were able to overcome it, the other candidates for either life or thinking wasn’t lucky/smart enough to get over it. In short: there are some factors that work against the living/intelligent beings.
Of course, it is only a theory and there are other, possible explanations for the “Great Silence” (=our missing “companion intelligences” in the Universe). For example: a low probability of life; or our inability to detect their signs; or we are the first intelligent races so it is not a surprise not to observe other intelligences in our light cone.
But we could adapt this Great Filter hypothesis for the future. Fred C. Adams (Long-term astrophysical processes, in: Global Catastrophic Risks, 2008) draws up our Universe’s very distant future up to 10^100 ears and regarding the survival of life, there are some fundamental turning points in the distant future of the Universe.
The first one is about the survuval of the earthly life. Our planet will be uninhabitable for an intelligent being within a 0.9 – 1.5 billion year and the biosphere will be “essentially sterilized in about 5.5 billion years” by the Sun. Notice that our environment in the Planetary System is not too life-friendly: a smaller start with 10% mass of the Sun would shine for trillion years (p. 44–46.). Regarding our actual knowledge about the pace of our human races’ technological developments, it seems to be possible to circumvent these problems–e.g. by migrating to another star.
The second barrier is more problematic. About 10^40 years later, because of the proton decay the matter in its traditional form will disappear and it means the “life as we know it”. (p. 47.)
It seems to be a serious “Great Filter” regarding the future of life and it would be a real challenge to find a solution which would be able to guarantee the survival of the life in this radically different physical environment. Of course, 10^40 year seem to be an unimaginably long time–but notice that it is not the end of the history of our Universe. The remains of the earlier era: the last black holes will be evaporated within a 10^100 years and only after it begins that epoch when “predictions of the physical universe begin to lose focus”. (p. 49.)
In other worlds: the living period (its end will be caused by the baryon decay) is like a phenomenon disappearing after the first trillionth – trillionth – trillionth… second of the Big Bang. A 10^40 years are simply negligible to the remaining period of time.
So it isn’t evident to argue that the “aim” of our whole Universe is that momentary phenomenon of life. However, the final conclusion of the Strong Anthropic Principle is that the appearance of life is a necessity. But why not, for example, the black holes?
So we have two choices. We can either refuse the Strong Anthropic Principle as a ridiculous and flawed theory (and I tend to do it) or we can ask how it would be possible for the future life to survive these two Great Filters: the baryon and the black hole barriers–and it is a really exciting question.
15 July 2015
10 July 2015
It would be even more fatal to create a super bomb–e.g. an artificial black hole–which can destroy everything but keeps intact the laws of physics. But this not the end of the possibilieties since it is imaginable that we could destroy somehow not only the physically existing Universe but the physical laws themselves too.
02 July 2015
Max Tegmark interprets the multiverse as the manifestation of every mathematically possible world. It is a form of mathematical Platonism, and the main thesis is that on the one hand, anything is possible mathematically exists in reality. On the other hand, everything is governed by the rules of mathematics. “Mathematical” means in this case that every combination of different sets of physical laws and constants, or even different equations exist. In other words: according to Tegmark, all words can be described by mathematics and every imaginable combination is manifested in a really existing world. The core of Tegmark’s concept is that mathematics is equal to physics in a certain sense, since it describes the world ruled by physical laws.
But it is not sure that even our universe can be described perfectly by mathematics and perhaps only our belief suggests that every natural phenomenon is controlled by either deterministic, or probability or evolutionary laws. Inter alia, it is possible that the Great Unified Theory (GUT) doesn’t exist, since there is no mathematics to describe every connection. It is perhaps only about our inability to give a coherent description about reality, since our tools (including our minds, mathematics and logic) aren’t appropriate for it.
Or, it is imaginable that there are universes that cannot be described by mathematics at all: after all, mathematics is based on the presumption of the conservation of some rules. Thus, it is not necessarily well-founded to state that every universe is mathematical in nature. So we can imagine whole universes (albeit they wouldn’t be biofil) without mathematically interpretable natural laws. In other words: although they exist, they cannot be described by one or other mathematical form of physical laws.
Traditionally, we distinguish existing and non-existing worlds and the main sin of modal realism is that it intermixes these two categories. Now we can introduce a third kind of universes which differ from both the “existing” and “non-existing” ones and since per definitionem it is impossible to give a scientific description about their features, they don’t belong to the realm of physics.