Essay Abstract

A central challenge in studies of the origin of life is that we don't know whether life is 'just' very complex chemistry, or if there is something fundamentally distinct about living matter. What's at stake here is not merely an issue of complexification; the question of whether life is fully reducible to just the rules chemistry and physics (albeit in a very complicated manner) or is perhaps something different, forces us to assess precisely what it is that we mean by the very nature of the question of the emergence of life. I argue that if we are going to treat the origin of life as a solvable scientific inquiry (which we certainly can and should), we must assume, at least on phenomenological grounds, that life is nontrivially different from nonlife. As such, a fully reductionist picture may be inadequate to address the emergence of life. The essay focuses on how treating the unique informational narrative of living systems as more than just complex chemistry may open up new avenues for research in investigations of the origin of life. I conclude with a discussion of the potential implications of such a phenomenological framework - if successful in elucidating the emergence of life as a well-defined transition - on our interpretation of life as a fundamental natural phenomenon.

Author Bio

Sara Imari Walker is a NASA Astrobiology Postdoctoral Fellow working in the Beyond Center for Fundamental Concepts in Science at Arizona State University. She received her Ph.D. in Physics and Astronomy from Dartmouth College. She then worked as postdoctoral fellow in the NSF/NASA Center for Chemical Evolution and the NASA Astrobiology Institute Center for Ribosomal Origins and Evolution based at the Georgia Institute of Technology. She is also member of the leadership council for the space science research and education nonprofit Blue Marble Space and a researcher at the Blue Marble Space Institute of Science.

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  • [deleted]

Sara,

A good philosophical or biological essay but... "which of our basic physical assumptions are wrong?"

By the way, how did you get top community rating only a few seconds after your essay appeared?

Pentcho Valev pvalev@yahoo.com

    Hello Ms.Walker,

    You have chance to work at the Nasa astrobilogy institute. It is my passion with piano and guitar. The anthropical principle is fascinating in fact.

    The origin of life is fascinating, in fact the mass and its evolution is fascinating. adenin, guanin, cytosin and thymin ....fascinating.the acids are really inetresting when we insert the serie of uniqueness for the quantization.

    The electromagnetism seems with the themrodynamics showing the road of stabilities. The diversity due to the number of combinations become very very incredible at the universal scale.a small human can have a small h in cm or a big h in meter, with all the colors of the light. The thermodynamics is universal in fact. The combinations imply a complexity of combinations implying lifes.

    Good luck in this contest

    Regards

      • [deleted]

      Sara,

      Pg 3 "We must therefore assume, right at the outset, that the "all life is chemistry" picture is inadequate to address the question at hand. We must ask, if life is not just complex chemistry, then what is it?"

      One of my mentors, a Professor Emeritus of Electrical Engineering, since deceased, stated that "everything" is a specialized form of "energy."

      Pg. 3 "As we now learn it in school, the central dogma of molecular biology states that information flows from DNA - RNA - protein. In reality the situation is much more complicated than this simple picture suggests."

      I realize your essay is not about the specific structure of biological organisms, but about "information" the structure contains. (74 instances of the term "information" in the essay)

      It is the form the information takes that is important when referring to "Shannon information," and in the context of biological DNA "information", it is in part its helical structure, and it is very efficient. DNA Digital Encoding

      I wonder how an intelligent species would encode information, and transfer it in some manner, such that it would be understood by another intelligent species that they did not have prior contact? Perhaps you could ask Paul Davies.

      Top-down causation may not be appropriate, perhaps mutual causation. It has been demonstrated that a pair of geometric structures, if properly paired, mutually define their dimensional sizes. See the IEEE paper referenced in topic 1294.

      Then there is the issue of, "why helical?" A somewhat dated article covers the issue. Chirality What possible influence in the universe is responsible for all the helicity and spin, with a left hand bias?

        Frank, I have postulated that it is the C-field or gravito-magnetic field that is responsible for the left-handed-only neutrinos, W and Z bosons, and even the left-handed biological molecules. This is maintained in all of my FQXi essays, but for the relevance of the C-field to quantum mechanics, see my current essay,

        The Nature of the Wave Function

        Sara, I apologize for posting about an off-topic, but it seemed relevant. I have printed out your essay and will comment after I have studied it.

        Edwin Eugene Klingman

        Hi Pentcho,

        The physical assumption challenged is that life is only trivially distinguishable from nonlife and that there is no new physics to be understood by studying the origin of life.

        I have no idea how the community rating happened! But it looks like its been sorted-out.

        Thanks for your interest!

        Steve,

        I agree that the origin of life is fascinating. And, thanks for the well wishes!

        Hello Frank,

        Thanks for the interesting points.

        I agree helicity is fascinating, and definitely part of the informational narrative of life.

        Although I stressed top-down causation in the essay, implicitly it is always a combination of causal factors, and could never be just top-down. So 'mutual causation' is always the case. The interesting thing in biology is that something which is nonphysical or virtual (but must of course be instantiated in physical structures) appears to have causal efficacy.

        You ask a very tough question about the possibility of a "universal message encoding" that any sufficiently intelligent beings could understand. I will think on this some - if I have any good insights, I post a follow-up reply.

        Best,

        Sara

        Edwin, thanks for adding to the discussion here. I look forward to reading your comments on my essay!

        • [deleted]

        You got top community rating from the very beginning but then my reaction prompted some prudent administrator to sort things out? I should have reacted earlier when other favorites instantly occupied top positions (and are still there). What a fair contest!

        Pentcho Valev pvalev@yahoo.com

        Hi Sarah,

        nice essay.

        "I stressed top-down causation in the essay, implicitly it is always a combination of causal factors, and could never be just top-down. So 'mutual causation' is always the case. The interesting thing in biology is that something which is nonphysical or virtual (but must of course be instantiated in physical structures) appears to have causal efficacy."

        Nicely stated - I agree fully!

        best wishes

        George

          Dear Sara

          It is refreshing to leave the world of photons, Relativity and Quantum conundrums for a while, to read your very well written and thought-out essay about a related area of science. It reminded me again that I have not yet read Schrödinger's "What Is Life?" if only for historical reasons. I think I understood your thesis here, but do not agree with it - that studying the origin of life life requires a new physical paradigm to explain the process why some molecules started self-reproducing.

          Perhaps the reason I stick to my reductionist approach is that in a model of the universe I have cooked up Beautiful Universe Theory (BU) the causal and local self-assembly of universal building blocks is the only interaction possible. Moreover this BU only exists in one universal 'now' state - ie the concept of time, of past and future future, does not exist as a physical dimension. State A affects and changes the next State B, but not vice-versa. Therefore I do not agree - in pure physical terms - to the 'vice-versa' in your statement ' It is the information encoded in the current state that determines the dynamics and hence the future state (s) and vice versa."

          But because a living organism has a definite set of cyclic states , say ABCDEFG ABCDEFG ABCDEFG that repeat themselves it can seem that the G state appears before and is the cause of the A state, so your 'vice-versa' makes biological sense. Yet it it does not require any new physics to implement the process.

          The other thing I had a problem with is 'top-bottom causation' since you yourself in footnote 5 say it is difficult to define the concept.

          Someone said my BU theory can be classified as a sort of cellular automata, and since you have studied artificial life you may accept the idea that the universe as a whole is always 'living' because it changes dynamically all the time (that word is inescapable!) , but that in certain clusters of molecules this 'living' becomes cyclic and can be called Life?

          If you feel like an easy-to-read fqxi essay check out my colorfully illustrated my fqxi essay Fix Physics!

          With best wishes

          Vladimir

            • [deleted]

            Sara,

            An earlier essay, topic 1416, "Topological solitons of ellipsoid field - particle menagerie correspondence", presented material on "spin". Also, this is the first essay that contains substantive information on solitons.

            I made the following comment on "Aug. 24, 2012 @ 00:59 GMT ":

            "Do you realize that you are presenting material as to why ionizing radiation is so destructive to biological tissue, the rotational form of the energy field allows it to efficiently couple to DNA and other helical structures within the body."

            The only thing I ever read about ionizing radiation is its energy level and nothing about the structural form of the energy. I realized last year that a helical type energy field would efficiently couple its energy to helical type structures within biological material. I had submitted a paper to an IEEE publications describing the helical structure. It did not fare well with peer review, as there were no experiments to "prove" that the helical field structures exist. I had included the Whyte "Chirality" reference, but that did not satisfy peer review.

            Someone with a good background in biology needs to write an article about how ionizing radiation with "spin" can efficiently couple its energy to biological structures. I have a paper that describes a basic helical energy structure, but it does not mention frequency or intensity, which would have to be considered as factors in how it would effect biological material.

            • [deleted]

            What a fascinating essay. I agree with Vladimir that it was a great escape from the low-level reality. Thank you for sharing it.

            Another essay here about cosmic engineering might relate to what you are saying. I think their essay is trying to say that living material often doesn't take the path of least resistance like non-living material would (ie. refraction of light by a material, deflection of light in a vacuum by a gravitational field).

            So, I guess one question that might be useful is "at what stage does this difference emerge"? My guess is the feeding stage. Living cells feed themselves, but the Voronoi cells that form in rocks do not. Then again, maybe this has nothing to do with finding the answer. I'm not sure.

              Thank you George, I very much enjoyed reading your essay as well!

              Best,

              Sara

              Hi Vladimir,

              Thank you for your kind comments. The central thesis is not quite "that studying the origin of life life requires a new physical paradigm to explain the process why some molecules started self-reproducing" as you state it. I completely agree that this particular aspect of the problem doesn't necessitate invoking any new physics. But, I think one much be very careful to distinguish trivially self-replicating systems from non-trivial self-replication. For an example of the former, one could look at Penrose blocks (Penrose & Penrose Nature 1958) - replication of a given seed structure (blocks aligned in one orientation or the other) is completely determined by local physics and chemistry. Contrast this with the logical structure of something like a von Neumann self-replicating automata (a very rough approximation to the way cells do business), which requires an algorithm to specify how the machine will replicate. In this scenario replication is explicitly programmed in the machine. The machine may therefore be programed to construct specific objects, and does so in some sense independent of direction by the implicit physics and chemistry (although of course adhering to the constraints imposed by physical law). Evolution is distinguished between these two possibilities since for trivial replicators only the physical structure evolves, while for nontrivial replicators you must evolve both the physical structures and the algorithms (e.g. one may loosely think of the dichotomy between genotype and phenotype in living systems and how they cannot be disentangled, leading to highly nontrivial evolutionary dynamics). So life is very different because it has explicit programming. That is the central thesis - we do not see this anywhere outside of the biosphere (computers here are included in the biosphere since they are derivative of it). So the critical question in the origin of life is how does this state of affairs arise in nature? My intuition is that it has everything to do with information transiting to an active cause in the system.

              You mention that organisms can have a definite cycle of states and I completely agree! But one trick in biology is that in your example, if you remove G say, which is a cause for A, another element in the system might take over for G. More interesting is that it is not a simple case of a cyclic process, but those states are tightly regulated, you would need information control with reliable protocols interfacing between elements of the system in your example to more accurately capture what biology is actually doing. That makes the situation both much more complicated but also more interesting.

              The information control issue is what is critically interesting to me. Top-down causation is a useful concept in this framework because you can more easily articulate the fact that the algorithm(s) play a distinctive role in the dynamics of the system. Everything about the way information is implemented in biology is context-dependent suggesting that these nonphysical or virtual aspects of the systems operation are changing with the states and vice versa and actively influencing the dynamics. To me that suggests that information is a cause in its own right - that is the radical departure from more traditional ways of doing business in physics and indicates that biology is much closer to to the realm of Turing than to the realm of traditional physics. Causation is not the difficult part to define however - so it is not the 'top-down' that is difficult. The difficult part is defining what are the 'levels' and what are the protocols/algorithms? So this is what I meant about difficulty with defining the concept - its a challenge for practical application. I think we are only at the beginning stages of trying to grasp at concrete answers to these questions as molecular biologists are now embarking on mapping regulatory networks in the cell (e.g. just this week with the ENCODE project).

              Thank you for the engaging discussion, and I will be sure to look into your BU theory.

              Best,

              Sara

              Hello S Halayka.

              Interesting observation! I am not sure the feeding stage is a satisfactory criteria in of itself though - in some sense certain chemical reactions are capable of "feeding" in the sense that they act like a rudimentary metabolism - catabolizing other chemical species. So you'd have to come up with a rigorous criteria for how feeding by living organisms is different than for these much simpler processes, which could be an interesting question to explore. Perhaps it has something to do with behavior?

              Best,

              Sara

              • [deleted]

              As I skimmed through your very interesting essay, I thought, "emergentism and panpsychism" are explanations for life to originate where ALL things have a "memory" and an "awareness". Humans are a bit arrogant, to view something as simple as water, H2O, having such properties.. Yet, it would be awful lonely if it did not have a crucial role in nurturing "life".

              To Seek Unknown Shores

              聽聽 http://fqxi.org/community/forum/topic/1409

              presents a model in End Notes, that satisfies a 6.25% possibility for any life to originate..

              Your essay was good!! Good luck.

                Hi Sara,

                Your essay presents your case very nicely. I agree that "informational efficacy" identifies something unique about living things, that certainly deserves more thought. But I tend to imagine this as resulting from the evolution of life, rather than as the defining feature of the process.

                You distinguish above between "trivial" and "non-trivial" kinds of self-replication, where the latter involves "explicit programming". More typically, I think biologists (going back to Darwin) say that what makes biological replication non-trivial is that it produces inheritable variations, which subjects the process to natural selection. What you emphasize - the informational control over the chemistry - is made possible by this selective process.

                The primitive self-replicating systems that eventually gave rise to life would not yet have shown this distinction between the programming and the chemistry it controls. For example, if such systems were something like bags of complex molecules that catalyzed each other's construction, all the molecules would have been part of the control-mechanism. I'm not clear through what stages the control-function might have become segregated into a specialized sub-system, eventually leading to the actual encoding of programmatic instructions in stable DNA molecules, with mechanisms for translating that information out into the protein-chemistry. But I can imagine many reasons why this would be advantageous - supporting a remarkably accurate/reliable replication process while including mechanisms that produce and control variation.

                I think you're right that this discussion is relevant to fundamental physics, though I would make the connection a little differently. I suggested at the end of my essay that there might be an evolutionary process in physics analogous to the biological process, but based on the functionality of communication rather than self-replication. Then we might think of the "laws of physics" as having a role similar to the function of DNA in biology... as a controlling information-structure that evolved to support the structure of interaction that makes things observable.

                In any case, thanks for your contribution -- this definitely brings a different perspective to the question of how information works in the physical world.

                Conrad