SHORT NOTE | doi:10.20944/preprints202208.0402.v1
Online: 24 August 2022 (02:28:26 CEST)
Evolution by natural selection is often viewed as an optimisation process where an organism's phenotypic traits are adapted gradually to improve its fitness. Because of the many different traits with potentially conflicting requirements, among other factors, this optimisation process may appear onerous. Building on recent mathematical work connecting optima and simplicity, we here show that for certain generic phenotype fitness requirements --- those based on physics and engineering principles --- optimal phenotypic shapes will tend to `simple', in the sense of low algorithmic or descriptional complexity. As a result, we argue that adapting to these types of generic fitness requirements will be a much `easier' task for natural selection, compared to a null expectation based on arbitrary optimisation requirements. Further, selection's task may be easier still due to the fact that optimal phenotypes for one set of generic fitness constraints may also be close to optimal for other generic constraints, such that adapting to one constraint yields the other `for free'.
SHORT NOTE | doi:10.20944/preprints202208.0330.v1
Subject: Mathematics & Computer Science, General & Theoretical Computer Science Keywords: Optimisation; simplicity; Kolmogorov complexity; physics
Online: 18 August 2022 (03:51:21 CEST)
Why are simple, regular, and symmetric shapes common in nature? Many natural shapes arise as solutions to energy minimisation or other optimisation problems, but is there a general relation between optima and simple, regular shapes and geometries? Here we argue from algorithmic information theory that for objective functions common in nature --- based on physics and engineering laws --- optimal geometries will be simple, regular, and symmetric. Further, we derive a null model prediction that if a given geometry is an optimal solution for one natural objective function, then it is a priori more likely to be optimal or close to optimal for another objective function.
ARTICLE | doi:10.20944/preprints202207.0323.v1
Subject: Mathematics & Computer Science, Probability And Statistics Keywords: Algorithmic probability; Kolmogorov complexity; prediction; induction
Online: 21 July 2022 (10:48:26 CEST)
Developing new ways to estimate probabilities can be valuable for science, statistics, and engineering. By considering the information content of different output patterns, recent work invoking algorithmic information theory has shown that a priori probability predictions based on pattern complexities can be made in a broad class of input-output maps. These algorithmic probability predictions do not depend on a detailed knowledge of how output patterns were produced, or historical statistical data. Although quantitatively fairly accurate, a main weakness of these predictions is that they are given as an upper bound on the probability of a pattern, but many low complexity, low probability patterns occur, for which the upper bound has little predictive value. Here we study this low complexity, low probability phenomenon by looking at example maps, namely a finite state transducer, natural time series data, RNA molecule structures, and polynomial curves. Some mechanisms causing low complexity, low probability behaviour are identified, and we argue this behaviour should be assumed as a default in the real world algorithmic probability studies. Additionally, we examine some applications of algorithmic probability and discuss some implications of low complexity, low probability patterns for several research areas including simplicity in physics and biology, a priori probability predictions, Solomonoff induction and Occam's razor, machine learning, and password guessing.
ARTICLE | doi:10.20944/preprints202007.0577.v1
Subject: Keywords: COVID-19; Coronavirus; SARS-CoV2; Random walks; Population dispersal; Diffusion; Lockdown; Confinement; Movement restrictions; Disease spread; Kuwait
Online: 24 July 2020 (10:57:04 CEST)
To mitigate the spread of the COVID-19 coronavirus, some countries have enforced more stringent non-pharmaceutical interventions in contrast to those widely adopted (for e.g. the state of Kuwait). In addition to standard practices such as enforcing curfews, social distancing, and closure of non-essential service industries, other non-conventional policies such as the total confinement of highly populated areas has also been implemented. In this paper, we model the movement of a host population using a mechanistic approach based on random walks, which are either diffusive or super-diffusive. Infections are realised through a contact process, whereby a susceptible host may be infected if in close spatial proximity of the infectious host. Our focus is only on the short-time scale prior to the infectious period, so that no further transmission is assumed. We find that the level of infection depends heavily on the population dynamics, and increases in the case of slow population diffusion, but remains stable for a high or super-diffusive population. Also, we find that the confinement of homogeneous or overcrowded sub-populations has minimal impact in the short term. Finally, we discuss the possible implications of our findings for total confinement in the context of the current situation in Kuwait.