Online research in philosophy

In September 1999 "Nature" magazine announced that atomic orbitals were di-rectly observed. Opposing it, Eric Scerri, editor-in-chief of "Foundations of Chemistry", claimed that what could be observed in the experiment was electron density, not orbitals. The main purpose of this paper is to consider philosophical and methodological aspects of the above controversy. Especially, the problems of direct observability and reality of theoretical entities are taken under detailed discussion. From the point of view of quantum mechanics there are not any reasons (...) to believe that orbitals exist. However, realistically treated orbitals are very effective tools in the laboratory practice of chemistry. (shrink)

The main aim of this paper is to present the motivation of the thesis that theoretical models con not fulfill the function of representation. The author analyses examples of such models used in molecular quantum mechanics.

The paper is focused on some aspects of experimental realism of Ian Hacking, and especially on his manipulability criterion of existence. The problem is here related to chemical molecules, the objects of interest in chemical research. The authors consider whether and to what extent this criterion has been applied in experimental practice of chemistry. They argue that experimentation on is a fundamental criterion of existence of entities in chemistry rather than experimentation with. Some examples regarding studies of structures of complex (...) compounds, taken from organic chemistry, are presented to support the authors' considerations. Chemists' laboratory practice depends strongly on the way that representations of entities on (or with) the experiments are used. The authors show that this point has not been given sufficient attention by the new experimentalists. (shrink)