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Pawel Tambor

Publications and source records attributed to Pawel Tambor.

3 recordsLinked to original sources

The laws of nature and the problems of modern cosmology

The notion that nature is subject to laws is exciting from many different viewpoints. This paper is based on the context of modern cosmology and presents a more philosophical discussion. It will list the significant interdisciplinary implications generated by various aspects of the contemporary scientific discussion about the status of laws of nature, especially their dynamic nature. Recent work highlights how multiple aspects of the observed universe still lack explanation and that several problems of standard cosmology still form the object of debate. Considering these issues, several proposals have been made that entail a revision of the concept of the law of nature, according to which the nature of time and of the relation between causality and natural laws ought to be reconsidered using approaches or viewpoints which point to philosophical issues. We argue that Tim Maudlin's concept of Fundamental Law of Temporal Evolution (FLOTE) and Nancy Cartwright's notion of the nomological machine provide new insights and valuable tools that can be used in the analysis of the status of laws in the context of cosmology and of complex systems theory. The limits of the traditional approach to laws of nature and of their mathematical formulation are highlighted in this context, as well as the fact that many of the ultimate properties of nature may turn out to be formally unpredictable or uncomputable.

physics.hist-ph

Dynamical Emergence of FRW Cosmological Models

Recent astronomical observations strongly indicate that the current Universe is undergoing an accelerated phase of expansion. The discovery of this fact was unexpected and resulted in the comeback of cosmological constant. The conception of standard cosmological model has its roots in this context. The paper relates to the methodological status of effective theories in the context of cosmological investigations. We argue that the standard cosmological model (LCDM model) as well as the CDM have a status of effective theories only, similarly to the standard model of particle physics. The LCDM model is studied from the point of view of the methodological debate on reductionism and epistemological emergence in the science. It is shown in the paper that bifurcation as well as structural instability notion can be useful in the detection of emergence the LCDM model from the CDM model. We demonstrate that the structural stability of the LCDM model can explain the flexibility of the model to accommodation of the observational data. We show that LCDM model can be derived from CDM as the bifurcation. It is an example of acausal derivation of Lambda term. The case study of emergence of LCDM model suggests that it can be understood in terms of bifurcation and structural stability issue. The reduction from the upper models represented in terms of dynamical system to low-level ones can be realized in any case by application of a mathematical limit (boundary crossing) with respect to the model parameter. It is a simple consequence of mathematical theorem about smooth dependence solutions with respect to time, initial condition and the parameters.

gr-qc

Bayesian reasoning in cosmology

We discuss epistemological and methodological aspects of the Bayesian approach in astrophysics and cosmology. The introduction to the Bayesian framework is given for a further discussion concerning the Bayesian inference in physics. The interplay between the modern cosmology, Bayesian statistics, and philosophy of science is presented. We consider paradoxes of confirmation, like Goodman's paradox, appearing in the Bayesian theory of confirmation. As in Goodman's paradox the Bayesian inference is susceptible to some epistemic limitations in the logic of induction. However Goodman's paradox applied to cosmological hypotheses seems to be resolved due to the evolutionary character of cosmology and accumulation new empirical evidences. We argue that the Bayesian framework is useful in the context of falsificability of quantum cosmological models, as well as contemporary dark energy and dark matter problem.

physics.data-an