Einstein presented Mach’s Principle in the article “Prinzipielles zur allgemeinen Relativitatstheorie” on 1918. He expressed in it his current ideas on gravity and ended a long reflection about the origin of Inertia which took his attention during the most prolific years of his scientific activity. This reflection has its origin in the reading of Ernst Mach’s “The Mechanics in its logical and historical development ” and especially in some ‘disputed’ passages present in the criticism of the Newton’s bucket experiment, where the Austrian Philosopher seems to suggest the existence of a causal link among the inertial characteristics of matter and the other stellar masses. This interpretation had a great success in the German scientific community and some Physicists, such as Friedlanders, Foppl, Hoffman and Einstein himself, developed machian ideas either from a theoretical point of view or from an experimental one. We my ask ourselves if this interpretation is the right one, if Mach really meant to suggest a link among Inertia and other stellar masses and, in this case, the reason why he did not deepen the argument anymore. In the following pages we’ll try to give an answer to these questions and we’ll recall some conclusions of a preceding essay, enriching them with a better interpretation of the most ambiguous passages. In fact these last ones achieves their correct meaning not only on the light of machian philosophy – as we showed in the above mentioned article – but also keeping in mind the ‘variation’ technique (or thought experiment) that Mach uses to lead to the extreme consequences the specific conceptual relations. Discussing for instance relation between relative and absolute motion, he introduces some equivocal sentences which we have to analyse in accordance to the particular context they are expressed in, and which do not present any general valour. At the end we’ll reach the double conclusion that Mach do not suggest any causal link between inertia and other stellar masses but that this hypothesis is easily deduced from his reasoning and from his philosophical convictions. As a matter of fact, this is the result of einstenian reflection onMach’s work: in the passages of Mechanics he first recognizes the general conjecture of a link between body inertia and the presence of other stellar masses and then he searches for a Theoretical Principle to formalise this hypothesis. He spent some years in reaching a complete formulation of Mach’s Principle, though the original considerations on machian ideas can be found in the article on 1912, at the end of the preliminary scalar theory of gravitation (he cites the Austrian Philosopher as his inspiration source). The short essay is of great interest because it represents the first Einstein’s step to axiomatize Mach’s conclusions on inertia origin. The task of this article is to suggest with more clearness the correct interpretation of the most ambiguous machian sentences and then to show, first how Einstein recognizes in Mach’s considerations a fundamental Principle of the future General Theory of Relativity and second which is his first attempt in modelling the relation between inertia and gravity.

In the middle of the nineteenth century the compact picture of Physics, that had been developing during the XVIII century, got into a crisis either for the appearance of new discoveries in the natural sciences or for the renewed scientist interest in the foundation of their subject. A decisive contribution for this process was supplied by Ernst Mach who showed the conceptual values and defects of Classical Mechanics with a learned historical analysis. In fact at the basis of the Machian work, besides the philosophical position that ties up with the traditional empiricism, there is the awareness that only the historical approach of physical principles clarifies their origin, meaning and accuracy. For example the concept of space and time were replaced by a formulation more pertaining to the experience after having showed the logical weakness and inconsistencies of the Newtonian definitions. Mach’s work produced a profitable debate among the german physicists and some of them tried to develop, deepen and transform in mathematical form his numerous critics and ideas. Among them the Einstein figure which got many suggestions from the reading of the “Mechanic in its logical and historical development”, evident either in the article of 1905 on the Special Relativity or in the laborious way that would carry him to the formulation of the General Relativity stands out best.

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Semantic space models of word meaning derived from co-occurrence statistics within a corpus of documents, such as the Hyper-space Analogous to Language (HAL) model, have been proposed in the past. While word similarity can be computed using these models, it is not clear how semantic spaces derived from different sets of documents can be compared. In this paper, we focus on this problem, and we revisit the proposal of using semantic subspace distance measurements. In particular, we outline the research questions that still need to be addressed to investigate and validate these distance measures. Then, we describe our plans for future research.

Presentation of talk held at SISFA 2012

In this article we will analyze the concept of relativity in the Machian work using dynamic frames provided by the Cognitive Science and now used successfully in Philosophy of Science. We will emphasize that the concept of relative can be divided into three types and with these new tools we will address the Machian interpretation of the Newton's bucket experiment.

In his Autobiographical Notes Einstein recognizes the importance of wonder in the cognitive process by stating that it occurs when an experi-ence comes into conflict with a sufficiently stable world of concepts. Al-ready in classical philosophy, wonder is considered the starting point of phi-losophizing as Plato highlights in Theaetetus and Aristotle in Metaphysics. To describe what the wonder consists of we will suggest a Dynamic Frames and we will use it to describe the role of wonder in the years of Einstein's formation.