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1.
This paper is concerned with Friedman׳s recent revival of the notion of the relativized a priori. It is particularly concerned with addressing the question as to how Friedman׳s understanding of the constitutive function of the a priori has changed since his defence of the idea in his Dynamics of Reason. Friedman׳s understanding of the a priori remains influenced by Reichenbach׳s initial defence of the idea; I argue that this notion of the a priori does not naturally lend itself to describing the historical development of space-time physics. Friedman׳s analysis of the role of the rotating frame thought experiment in the development of general relativity – which he suggests made the mathematical possibility of four-dimensional space-time a genuine physical possibility – has a central role in his argument. I analyse this thought experiment and argue that it is better understood by following Cassirer and placing emphasis on regulative principles. Furthermore, I argue that Cassirer׳s Kantian framework enables us to capture Friedman׳s key insights into the nature of the constitutive a priori.  相似文献   

2.
The problem of measurement is a central issue in the epistemology and methodology of the physical sciences. In recent literature on scientific representation, large emphasis has been put on the “constitutive role” played by measurement procedures as forms of representation. Despite its importance, this issue hardly finds any mention in writings on constitutive principles, viz. in Michael Friedman׳s account of relativized a priori principles. This issue, instead, was at the heart of Reichenbach׳s analysis of coordinating principles that has inspired Friedman׳s interpretation. This paper suggests that these procedures should have a part in an account of constitutive principles of science, and that they could be interpreted following the intuition originally present (but ultimately not fully developed) in Reichenbach׳s early work.  相似文献   

3.
No-conspiracy is the requirement that measurement settings should be probabilistically independent of the elements of reality responsible for the measurement outcomes. In this paper we investigate what role no-conspiracy generally plays in a physical theory; how it influences the semantical role of the event types of the theory; and how it relates to such other concepts as separability, compatibility, causality, locality and contextuality.  相似文献   

4.
This is a discussion of how we can understand the world-view given to us by the Everett interpretation of quantum mechanics, and in particular the rôle played by the concept of ‘world’. The view presented is that we are entitled to use ‘many-worlds’ terminology even if the theory does not specify the worlds in the formalism; this is defended by means of an extensive analogy with the concept of an ‘instant’ or moment of time in relativity, with the lack of a preferred foliation of spacetime being compared with the lack of a preferred basis in quantum theory. Implications for identity of worlds over time, and for relativistic quantum mechanics, are discussed.  相似文献   

5.
We make a first attempt to axiomatically formulate the Montevideo interpretation of quantum mechanics. In this interpretation environmental decoherence is supplemented with loss of coherence due to the use of realistic clocks to measure time to solve the measurement problem. The resulting formulation is framed entirely in terms of quantum objects. Unlike in ordinary quantum mechanics, classical time only plays the role of an unobservable parameter. The formulation eliminates any privileged role of the measurement process giving an objective definition of when an event occurs in a system.  相似文献   

6.
We call attention to the historical fact that the meaning of symmetry in antiquity—as it appears in Vitruvius’s De architectura—is entirely different from the modern concept. This leads us to the question, what is the evidence for the changes in the meaning of the term symmetry, and what were the different meanings attached to it? We show that the meaning of the term in an aesthetic sense gradually shifted in the context of architecture before the image of the balance was attached to the term in the middle of the 18th century and well before the first modern scientific usage by Legendre in 1794.  相似文献   

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8.
I argue that the Oxford school Everett interpretation is internally incoherent, because we cannot claim that in an Everettian universe the kinds of reasoning we have used to arrive at our beliefs about quantum mechanics would lead us to form true beliefs. I show that in an Everettian context, the experimental evidence that we have available could not provide empirical confirmation for quantum mechanics, and moreover that we would not even be able to establish reference to the theoretical entities of quantum mechanics. I then consider a range of existing Everettian approaches to the probability problem and show that they do not succeed in overcoming this incoherence.  相似文献   

9.
In this paper I assess whether the recently proposed “No De-Coupling” (NDC) theory of constitutive relevance in mechanisms is a useful tool to reconstruct constitutive relevance investigations in scientific practice. The NDC theory has been advanced as a framework theoretically superior to the mutual manipulability (MM) account of constitutive relevance in mechanisms but, in contrast to the MM account, has not yet been applied to detailed case studies. I argue that the NDC account is also applicable to empirical practice and that it fares better than the MM account on both theoretical and empirical grounds. I elaborate these claims in terms of applications of the NDC theory to two case studies of cognitive science research on the role of eye movements in mechanisms for cognitive capacities.  相似文献   

10.
As one of the most important second messengers, 3′,5′-cyclic adenosine monophosphate (cAMP) mediates various extracellular signals including hormones and neurotransmitters, and induces appropriate responses in diverse types of cells. Since cAMP was formerly believed to transmit signals through only two direct target molecules, protein kinase A and the cyclic nucleotide-gated channel, the sensational discovery in 1998 of another novel direct effecter of cAMP [exchange proteins directly activated by cAMP (Epac)] attracted a great deal of scientific interest in cAMP signaling. Numerous studies on Epac have since disclosed its important functions in various tissues in the body. Recently, observations of genetically manipulated mice in various pathogenic models have begun to reveal the in vivo significance of previous in vitro or cellular-level findings. Here, we focused on the function of Epac in the heart. Accumulating evidence has revealed that both Epac1 and Epac2 play important roles in the structure and function of the heart under physiological and pathological conditions. Accordingly, developing the ability to regulate cAMP-mediated signaling through Epac may lead to remarkable new therapies for the treatment of cardiac diseases.  相似文献   

11.
A basic premise of hyphenated history-and-philosophy-of-science is that theories of scientific change have to be based on empirical evidence derived from carefully constructed historical case studies. This paper analyses one such systematic attempt to test philosophical claims, describing its historical context, rationale, execution, and limited impact.  相似文献   

12.
Robert Merton observed that better known scientists tend to get more credit than less well known scientists for the same achievements; he called this the Matthew effect. Scientists themselves, even those eminent researchers who enjoy its benefits, regard the effect as a pathology: it results, they believe, in a misallocation of credit. If so, why do scientists continue to bestow credit in the manner described by the effect? This paper advocates an explanation of the effect on which it turns out to allocate credit fairly after all, while at the same time making sense of scientists’ opinions to the contrary.  相似文献   

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14.
Résumé La crustecdysone injectée dans l'écrevisse,Procambarus sinulans ne cause pas la mue chez l'animal intact mais l'accélère après ablation des pédoncules oculaires.  相似文献   

15.
The role of crustecdysone in the moulting crayfish   总被引:2,自引:0,他引:2  
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16.
Résumé La thymectomie chez des souris CF1 âgées de 1 mois est suivie comme dans le cas de la thymectomie néonatale de l'apparition d'anticorps antinucléaires. Le transfert adoptif de l'autoimmunité antinucléaire apparu chez des animaux thymectomisés à la naissance n'est possible que si les animaux receveurs sont eux-mêmes thymectomisés. Ces constatations mettent en évidence un rôle possible de contrôle des réactions autoimmunes par le thymus.  相似文献   

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18.
Zusammenfassung Während der Biosynthese von Cholesterol mit homogenisierter Rattenleber wird [2-14C] des Glycins viel besser eingebaut als [1-14C].Saccharomyces cerevisiae produziert radioaktives Squelen (ausser Ergosterol mit Radioaktivität des Ringsystems) mit [2-14C] Glycin und mit [3-14C] Serin, aber nicht mit [1-14C] Glycin.

Studies on Biosynthesis. Part VI. For Part V, seeA. K. Bose, K. S. Khanchandani andB. L. Hungund, Experientia,27, 1403 (1971). b) Presented at the 164th National Meeting of the American Chemical Society, New York, August, 1972.

The support of this research by Stevens Institute of Technology and Sandoz Foundation is gratefully acknowledged. We wish to thank Drs.P. T. Funke, M. S. Manhas, P. K. Bhattacharyya, M. Anchel andH. Levey for valuable discussions and help with some of the experiments.  相似文献   

19.
It has been and still is commonly believed by geologists and historians of geology alike that geological theory is an extrapolation from the empirical knowledge of the geology of a region. Abraham Gottlob Werner (1749–1817), whose theory concerning the origin of basalt and the minor role of volcanoes and the major role of water in the history of the earth's crust was eventually proven wrong in some respects, is usually cited as the prime example of a geologist who had not ventured beyond the confines of his native region, Saxony, and had developed a universal geological theory based almost entirely on his observations of that region. In this essay I show that the geology of Saxony played a relatively unimportant role in the development of Werner's universal geological theory; that he became a neptunist before he had closely examined the geology of Saxony; and that his explanation of the history of the earth's crust was as reasonable, if not more reasonable, than the explanations brought forth by those of his contemporaries who opposed his views.  相似文献   

20.
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