arXiv subjects

Ian von Hegner

Publications and source records attributed to Ian von Hegner.

9 recordsLinked to original sources

arXiv2024

Terrestrial Life in Light of the Copernican Principle

Although many solar systems have been discovered, only one example of life is known. Thus, terrestrial life represents merely one data point. Consequently, extrapolating from terrestrial life to life elsewhere in the galaxy and beyond is often seen as a limitation in the search for different forms of life. Essentially, attempting to extrapolate from terrestrial life to life elsewhere implies that terrestrial life is representative of all life, reflecting a geocentric viewpoint. However, in accordance with the Copernican principle, the opposite holds true. Asserting that terrestrial life must differ from other forms of life in the universe is, in fact, the geocentric viewpoint. For if life elsewhere is not like terrestrial life, then it is ipso facto different life; more precisely, if terrestrial life does not represent general life, then that life must represent special life, which the principle states it is not. This study employs the Copernican principle as a probability assessment, addressing critiques rooted in the implicit assumption of the existence of different extraterrestrial forms of life. If various fundamental forms of life indeed exist, then differences in the probabilities of their emergence can be expected, forming a probability scale. This holds significance because it not only allows for insights into the characteristics of the majority of life elsewhere but also facilitates the establishment of boundaries for categories of life as we do not know it. Thus, the Copernican-Darwinian principle provides a valuable tool for astrobiology and the search for life in the galaxy and beyond.

physics.pop-ph↗

arXiv2024

A Plethora of the Earth-like Planet: Ramifications of a Fuzzy World

One primary reason for the formulation of the term Earth-like planet and the search for such planets in the galaxy is because life has arisen in such a world. Thus, this search seems justifiable as it is known here what one is looking for. However, the Earth-like concept represents an attempt to set up sharp boundaries for an inhabited planet, even though nature often comes as continua. The analyses in this work show that the term does not represent a clear-cut entity as a general Earth-likeness cannot be abstracted. Thus, the complex variation of environment and life means that the singular term Earth-like planet is more appropriately treated as a fuzzy world. Such a fuzzification has the consequence of the term being not only more limited than assumed but may even be deceptive, as an Earth-like planet on one hand can be in a segment in which it does not seem particularly Earth-like, but still possesses life, but on the other hand can appear very Earth-like but not possess life anyway. An atmosphere can provide a biosignature by being displaced from thermodynamic equilibrium, derived from antagonistic adaptation, in which life as a double-edged sword, on one hand, continuously makes the external environment less favourable for itself, while on the other, increasing its capacity to do so. Yet, there is an issue with using this as a search criterion for potentially inhabited worlds, as such planets can give impressions that do not reflect what has gone on; they can even give a ghost biosignature. These novel analyses do not represent a limitation in the search for Earth-like planets, as the plethora of Earth-like planets shows the possibility that the number of inhabited worlds can be large, but do represent a limitation in the search for life on such worlds.

physics.pop-ph↗

arXiv2021

Extreme exoworlds and the extremophile paradox

Extremophiles have gained prominence by providing an experimental approach to astrobiology. Extremophiles gain equal value by being part of a framework for high-level characterisation of the evolutionary mechanisms that must necessarily restrict or promote their emergence and presence on solar system bodies. Thus, extremophiles exist in extreme environments, and therein lies the paradox: extremophiles can only live in extreme environments but yet are not able to originate in such environments. Therefore, even though the range of extremophile capabilities in extreme environments is wider than that in mesophiles, the range of their emergence possibilities is still equally restricted. Therefore, even if one locates an extreme exoworld where terrestrial extremophiles could live here-and-now, it can be predicted that no extremophile analogues are present anyway. Furthermore, it is possible for a world to be uninhabited, yet be habitable, and therein arises the extreme environment paradox: an extreme environment can sustain chemical evolution as well as arriving non-native life, yet native life cannot be built up in that very environment. Thus, life may exist on an extraterrestrial extreme world (if imported there), and chemical evolution may be present on that world. However, it can be predicted that there is no native life anyway. This situation can be predicted to function as a chemosignature and eventually as a biosignature. However, the fact that a non-native extremopile in principle can exist in extreme environments may demonstrate that the intermediate step between chemical evolution and extremophiles can still occur in the form of a statistical deviation.

q-bio.PE↗

arXiv2021

A trampoline effect occurring in the stages of planetary reseeding

Impactors have hit the Earth since its formation and have continued to be infrequent guests throughout the Earth's history. Although the early part of the Earth's history was marked by these violent events, life was present early, possibly existing already in the Hadean Eon. It is possible that life has been, and still is, transported between the worlds of the solar system, owing to impacts leading material away from the impact region. Beyond this lithopanspermia theory, in the in the so-called refugium hypothesis, ejected material has been suggested to also return to its home planet and 'reseed' life after the world has recovered after a global impactor, thus restarting evolution.In addition to such impactors, more frequent impacts from smaller non-sterilizing impactors existed during the Heavy Bombardment epoch, feeding material potentially harbouring viable organisms into near Earth space.

astro-ph.EP↗

arXiv2020

A protocell design for bioaccumulation applications

This review article provides a specific example of recombinant cell and protocell technology, moving from what is presently known to suggesting how novel application of existing methodologies could be utilized to design a complex synthetic system in form of a self-sufficient light empowered protocell. A practical application of protocells using a primary example of desalination in water treatment is given, followed by a more general review regarding bioaccumulation and bio-diagnostics, outlining the possibilities associated with applications of protocells.

physics.bio-ph↗

arXiv2020

Interplanetary transmissions of life in an evolutionary context

The theory of lithopanspermia proposes the natural exchange of organisms between solar system bodies through meteorites. The focus of this theory comprises three distinct stages: planetary ejection, interplanetary transit and planetary entry. However, it is debatable whether organisms transported within the ejecta can survive all three stages. If the conjecture is granted, that life can indeed be safely transmitted from one world to another, then it is not only a topic pertaining to planetary science but also biological sciences. Hence, these stages are only the first three factors of the equation. The other factors for successful lithopanspermia are the quality, quantity and evolutionary strategy of the transmitted organisms. When expanding into new environments, invading organisms often do not survive in the first attempt and usually require several attempts through propagule pressure to obtain a foothold. There is a crucial difference between this terrestrial situation and the one brought about by lithopanspermia. While invasive species on Earth repeatedly enters a new habitat, a species pragmatically arrives on another solar system body only once; thus, an all-or-nothing response will be in effect. The species must survive in the first attempt, which limits the probability of survival. In addition, evolution sets a boundary through the existence of an inverse proportionality between the exchanges of life between two worlds, thus further restricting the probability of survival. However, terrestrial populations often encounter unpredictable and variable environmental conditions, which in turn necessitates an evolutionary response. Thus, one evolutionary mode in particular, bet hedging, is the evolutionary strategy that best smooth out this inverse proportionality.

physics.pop-ph↗

arXiv2019

A limbus mundi elucidation of habitability: the Goldilocks Edge

The habitable zone is the circumstellar region in which a terrestrial-mass planet with an atmosphere can sustain liquid water on its surface. However, despite the usefulness of this concept, it is being found to be increasingly limiting in a number of ways. The following is known: (i) Liquid water can exist on worlds for reasons unrelated to its specific distance from a star. (ii) Energy sources can exist for reasons unrelated to the distance to a star. Furthermore, the habitable zone is based on both astronomy: the distance and stellar energy, and chemistry: liquid water and the right temperature. However, these factors are only part of the consideration. Thus, discussions of habitability and the possibility for the emergence of life on a world must consider the evolutionary principles that govern life as well as the laws that govern stellar and planetary science. This is important because the following is also known: (iii) The time window for the emergence of life is within 600 million years. (iv) The Earth was an extreme environment overall in the period when this window existed. (v) The first life was necessarily fragile. Therefore, chemical evolution must have taken place in a relatively protected and restricted environment. Thus, rather than as in the Goldilocks zone, which focuses too narrowly on the world as a whole, this paper suggests that it is better to focus on a particular region and time period on a world, in which fitting conditions for habitability exist. Thus, the following is suggested: The Goldilocks Edge is a spatial and temporal window on an astronomical body or planemo, where liquid solvents, SPONCH elements, and energy sources exist. Furthermore, since the mere presence of these do not in themselves necessarily lead to the emergence of life, this possibility only arises when these interact. Thus, the prebiotic spot will be suggested.

physics.pop-ph↗

arXiv2019

Extremophiles: a special or general case in the search for extra-terrestrial life?

Since time immemorial life has been viewed as being fragile, yet over the past few decades it has been found that many extreme environments are inhabited by organisms known as extremophiles.Knowledge of their emergence, adaptability, and limitations seems to provide a guideline for the search of extra-terrestrial life, since some extremophiles presumably can survive in extreme environments such as Mars, Europa, and Enceladus. Due to physicochemical constraints, the first life necessarily came into existence at the lower limit of lifes conceivable complexity.Thus, the first life could not have been an extremophile, furthermore, since biological evolution occurs over time, then the dual knowledge regarding what specific extremophiles are capable of, and to the analogue environment on extreme worlds, will not be sufficient as a search criterion.This is because, even though an extremophile can live in an extreme environment here-and-now, its ancestor however could not live in that very same environment in the past, which means that no contemporary extremophiles exist in that environment.Furthermore, a theoretical framework should be able to predict whether extremophiles can be considered a special or general case in the galaxy.Thus, a question is raised: does Earths continuous inhabitability represent an extreme or average value for planets? Thus, dependent on whether it is difficult or easy for worlds to maintain this inhabitability, the search for extra-terrestrial life with a focus on extremophiles will either represent a search after dying worlds, or a search after special life on living worlds, where one focus too narrowly on extreme values.

physics.bio-ph↗

arXiv2019

The improbable event of spontaneous cell rejuvenation

Unlike most other laws of nature, the second law of thermodynamics is of a statistical nature, according to Boltzmann, meaning that its reliability arises from the vast number of particles present in macroscopic systems. This means that such systems will lead towards their most likely state, that is, the one with the most homogeneous probability distribution. However, Boltzmann states that entropy-decreasing processes can occur (without doing any work) - it is just very improbable. It is therefore not impossible, in principle, for all 6 x 10^23 atoms in a mole of a gas to spontaneously move to one half of a container; it is only fantastically unlikely. A similar idea has here been applied to a human cell. All somatic cells seem to age and deteriorate in unfavorable conditions. If the ageing process is defined as the accumulation of dysfunctional polymers resulting from, among other things, chemical bond breakage, where polymers aggregate into harmful arrangements, spreading out randomly in the cell and leading to an altered function, then it also applies that there will be a difference in entropy between, for instance, a 20-year old individual and the same individual at age 80. The goal of this article is to demonstrate that the second law does not tell us that the cell necessarily must go toward a high entropy state and stay that way but that it is possible - according to statistical mechanics - for an old cell to experience a return to a younger state. We find the probability of this spontaneous return to a more ordered state to be expressed by P = 10^(-202)^(-889). In spite of this number, it does show that a reversal of the ageing process is not prohibited by nature. There is a theoretical possibility of rejuvenation. Whether this will ever become a practical reality is another matter.

physics.gen-ph↗