Essay Abstract

The question of the ultimate limits of physics can be construed in two different, but closely related, senses: as (1) What is ultimately knowable in physics? and as (2) What is ultimately doable in our physical environment? I argue that, while we may soon have understood the origin of what is conventionally meant by “physics”—a particular low-energy limit (“vacuum”) of the string theory or any alternative unified field theory—such knowledge needs to be supplemented by a complete understanding of the observation-selection effects. In particular, precise determination of the habitable region in the parameter space will enable us to explain the very origin of physics in naturalistic terms and, thus, circumscribe all possible physics knowledge. Precise cartography of this huge Archipelago will enable the act of ultimate engineering: transcending effective dynamical laws and modifying entire spacetimes for the benefit of self-aware substructures (i.e., observers).

Author Bio

Milan M. Cirkovic obtained PhD in physics from the State University of New York at Stony Brook, and currently is a senior researcher at the Astronomical Observatory of Belgrade. His primary research interests are in the fields of astrobiology, astrophysics (in particular baryonic dark matter and physics of galaxies), philosophy of science, and future studies. He co-edited the anthology on Global Catastrophic Risks (Oxford University Press, 2008), wrote two monographs, about 100 research papers, and translated several books, including titles by Richard P. Feynman and Sir Roger Penrose.

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Quite interesting essay. I loved the bit about Lem!

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I found your essay to be interesting. You might want to look at my essay

http://www.fqxi.org/community/forum/topic/494

which discusses how the cosmological constant is set by the existence of a quantum critical point or quantum phase transition. This tends to result in an extremization of complexity. There is also Abhijnan Rej's excellent paper:

http://www.fqxi.org/community/forum/topic/505

which illustrate computability aspects to this problem. These matters have a direct bearing on your archipelago. I think that Rej's perspective feeds well into what I have been working on, where there exists a statistics over a set of information bits, or quantum bits, and the ordering of these bits is in a quantum phase transition determined by a quantum fluctuation

Lawrence B. Crowell

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I have found the recent public voting dynamics extremely interesting.

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This essay displays a rare quality of blending clarity of scientific argument with the refreshing beauty of language of metaphor. It also presents the problem of intelligent life in the broadest possible perspective (one might say a total perspective, since it deals with our whole 'Universe' as a mere special case among countless possibilities, in the best Copernican tradition) and thus establishes an important intelectual framework that will be of great assistance for all who seek further insights, either theoretical or practical, that continue to shape our understanding of Life in the Universe.

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Dear Milan,

i tried making efforts to understand the gist of your essay. What i find is that one needs to treat our universe not as a single entity but multiverse like. This does throw multi-dimensionality into the picture. What about the relativity theory with its four dimensions, three of space and fourth of time, will it hold and if so how we picture the things in the multiverse! Are quantum fluctuations are producing such effects constantly? Please enlighten me with gist of your theme, thanks.

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Dear Srdja,

You seem to present here only half the story. While Milan’s paper is brilliant, all the other essays are so bad in comparison that they deserved only low public votes, is this not right?

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Dear Abhijnan, Lawrence, and Srdja,

Great thanks for your interest and kind words! You're quite right, quantum information theory is quite relevant for the problem, esp. in view of "coarse-graining" of cosmological initial conditions.

Dear NN,

The theory of chaotic/eternal inflation does imply constant production rate of new "bubble universes" (though the term is somewhat old-fashioned) out of the Planck energy substratum. That's Linde cosmology. This generates the multiverse, although it still does not tell us much about the effective physical laws in individual universes at low energies (that depends on the energy scaling of the breakdown of primordial grand symmetry). Other issues are presented well in Tegmark's review paper, which I wholeheartedly recommend (it's a good read, too!)...

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Dear Milan

You wrote: Precise cartography of this huge Archipelago will enable the act of ultimate engineering: transcending effective dynamical laws and modifying entire spacetimes for the benefit of self-aware substructures (i.e., observers).

My research is on the self-awareness of the observer. Observer and universe belong to the same reality. In direct experience where there is no mind processing universe and observer become one.

Yous Amrit

My essay here is about Awakening of the Observer in Physics.

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