The notion that the metric field in general relativity can be understood as a property of space-time rests on a feature of the theory sometimes called universal coupling—the claim that rods and clocks “measure” the metric in a way that is independent of their constitution. It is pointed out that this feature is not strictly a consequence of the central dynamical tenets of the theory, and argued that the metric field would better be regarded as a field in space-time, rather (...) than as the very fabric of space-time itself. (shrink)

In this paper I critically review the long history of attempts to formulate and derive the geodesic principle, which claims that massive bodies follow geodesic paths in general relativity theory. I argue that if the principle is interpreted as a dynamical law of motion describing the actual evolution of gravitating bodies as endorsed by Einstein, then it is impossible to apply the law to massive bodies in a way that is coherent with his own field equations. Rejecting this canonical interpretation, (...) I propose an alternative interpretation of the geodesic principle as a type of universality thesis analogous to the universality behavior exhibited in thermal systems during phase transitions. (shrink)

In this paper I critically review the long history of attempts to formulate and derive the geodesic principle, which claims that massive bodies follow geodesic paths in general relativity theory. I argue that if the principle is interpreted as a dynamical law of motion describing the actual evolution of gravitating bodies as endorsed by Einstein, then it is impossible to apply the law to massive bodies in a way that is coherent with his own field equations. Rejecting this canonical interpretation, (...) I propose an alternative interpretation of the geodesic principle as a type of universality thesis analogous to the universality behavior exhibited in thermal systems during phase transitions. (shrink)

As I have read the scholium, it divides into three main parts, not including the introductory paragraph. The first consists of paragraphs one to four in which Newton sets out his characterizations of absolute and relative time, space, place, and motion. Although some justificatory material is included here, notably in paragraph three, the second part is reserved for the business of justifying the characterizations he has presented. The main object is to adduce grounds for believing that the absolute quantities are (...) indeed distinct from their relative measures and are not reducible to them. Paragraph five takes this up for the case of time. Paragraphs eight to twelve endeavor to do this for rest and motion by appealing to their properties, causes and effects. In arguing that absolute motion is not reducible to any particular form of the relative motion of bodies with respect to one another, and thus, as is directly argued in the third argument, must be understood in terms of motionless places, Newton thereby constructs an indirect case that absolute space is indeed something distinct from any relative space. Paragraph thirteen functions as conclusion to this line of inquiry and comments on how, in the light of this, the names of these quantities are to be interpreted in the scriptures. The third and final part consists of paragraph fourteen alone, and addresses the question: given that true motion is motion with respect to absolute space, but the parts of the latter are not perceivable, is it possible for us to know the true motions of individual bodies? Newton illustrates how this may be done from the evidence provided by their apparent motions and the forces which are the causes and effects of true motion. This forms a bridge to the body of the work insofar as the purpose of the Principia, according to Newton, is to show how this, and the converse problem, of inferring true and apparent motions from the forces, can be dealt with.Part II of this paper will appear in the next issue of Studies in History and Philosophy of Science. (shrink)

sn y™to˜er —nd xovem˜er IWHUD just over two ye—rs —fter the ™ompletion of his spe™i—l theory of rel—tivityD iinstein m—de the ˜re—kthrough th—t set him on the p—th to the gener—l theory of rel—tivityF ‡hile prep—ring — review —rti™le on his new spe™i—l theory of rel—tivityD he ˜e™—me ™onvin™ed th—t the key to the extension of the prin™iple of rel—tivity to —™™eler—ted motion l—y in the rem—rk—˜le —nd unexpl—ined empiri™—l ™oin™iden™e of the equ—lity of inerti—l —nd gr—vit—tion—l m—ssesF „o interpret (...) —nd exploit this ™oin™iden™eD he introdu™ed — new —nd powerful physi™—l prin™ipleD soon to ˜e ™—lled the ’prin™iple of equiv—len™e4 upon whi™h his se—r™h for — gener—l theory of reE l—tivity would ˜e ˜—sedF woreoverD with the ™ompletion of the theory —nd throughout the rem—inder of his lifeD iinstein insisted on the fund—ment—l import—n™e of the prin™iple to his gener—l theory of rel—tivityF iinstein9s insisten™e on this point h—s ™re—ted — puzzle for philosophers —nd histori—ns of s™ien™eF st h—s ˜een —rgued vigorously th—t the prin™iple in its tr—dition—l formul—tion does not hold in th™ gener—l theory of rel—tivityD gonsiderD for ex—mpleD — tr—dition—l formul—tion su™h —s €—uli9s in his IWPI Encyklopadie —rti™leF por €—uli the prin™iple —sserts th—t one ™—n —lw—ys tr—nsform —w—y —n —r˜itr—ry gr—vit—tion—l eld in —n innitely sm—ll region of sp—™eEtimeD ˜y tr—nsforming to —n —ppropri—te ™oordin—te system @€—uli IWPID pF IRSAF sn responseD su™h eminent rel—tivists —s ƒynge @IWTHD pF ixAD —nd even iddington ˜efore him @IWPRD ppF QW{RIAD h—ve o˜je™ted th—t — ™oordin—te tr—nsform—tion or ™h—nge of st—te of motion of the o˜server ™—n h—ve no ee™t on the presen™e or —˜sen™e of — gr—vit—tion—l eldF „he presen™e of — ’true4 gr—vit—tion—l eld is determined ˜y —n inv—ri—nt ™riterionD the ™urv—ture of the metri™F „he gr—vit—tionEfree ™—se of spe™i—l rel—tivity is just the ™—se in whi™h this ™urv—ture v—nishesD where—s the true gr—vit—tion—l elds of gener—l rel—tivity —re distinguished ˜y the nonv—nishing of this ™urv—tureF „his o˜je™tion h—s immedi—te r—mi™—tions for the ’iinstein elev—tor4 thought experimentD whi™h is ™ommonly used in the formul—tion of the prinE ™iple of equiv—len™eF sn this thought experimentD — sm—ll ™h—m˜ers su™h —s.... (shrink)

I argue that, contrary to folklore, Einstein never really cared for geometrizing the gravitational or the electromagnetic field; indeed, he thought that the very statement that General Relativity geometrizes gravity "is not saying anything at all". Instead, I shall show that Einstein saw the "unification" of inertia and gravity as one of the major achievements of General Relativity. Interestingly, Einstein did not locate this unification in the field equations but in his interpretation of the geodesic equation, the law of motion (...) of test particles. (shrink)

I describe how relativistic field theory generalizes the paradigm property of material systems, the possession of mass, to the requirement that they have a mass–energy–momentum density tensor T µ associated with them. I argue that T µ does not represent an intrinsic property of matter. For it will become evident that the definition of T µ depends on the metric field g µ in a variety of ways. Accordingly, since g µ represents the geometry of spacetime itself, the properties of (...) mass, stress, energy, and momentum should not be seen as intrinsic properties of matter, but as relational properties that material systems have only in virtue of their relation to spacetime structure. (shrink)

It is widely believed that the development of the general theory of relativity coincided with a shift in Einstein’s philosophy of science from a kind of Machian positivism to a form of scientific realism. This article criticizes that view, arguing that a kind of realism was present from the start but that Einstein was skeptical all along about some of the bolder metaphysical and epistemological claims made on behalf of what we now would call scientific realism. If we read Einstein’s (...) philosophy of science in its proper late nineteenth-and early twentieth-century philosophical context, we find that a kind of Duhemian under determinationist holism and conventionalism was more important to Einstein than either positivism or realism. And, reading his philosophy of science in its proper scientific. (shrink)

The story of Einstein's struggle to create a general theory of relativity, and his early discontentment with the final form of the theory , is well known in broad outline. Thanks to the work of John Norton and others, much of the fine detail of the story is also now known. One aspect of Einstein's work in this period has, however, been relatively neglected: Einstein's commitment to Mach's ideas on inertia, and the influence this commitment had on Einstein's work on (...) general relativity from 1907 to 1918. In this paper published writings and archival material are examined, to try to reconstruct the details of Einstein's thinking about inertia and gravitation, and the role that Mach's ideas played in Einstein's crucial work on the general theory. By the end, a clear picture of Einstein's conceptions of Mach's ideas on inertia, and their philosophical motivations, will emerge. Several surprising conclusions also emerge: Einstein's desire for a Machian gravitation theory was the central force driving his work from 1912 to 1915, keeping him going despite numerous frustrating setbacks; Einstein's continued commitment to Mach's ideas in 1916–1917 kept him at work trying various strategies of modification of the field equations, in order to exclude anti-Machian solutions ; and as late as early 1918, Einstein was ready to call the whole General Theory a failure if no way of squaring it with Mach's ideas on inertia could be found. But by 1920 Einstein advocated a view that granted spacetime independent existence with physical qualities of its own, a complete break with his earlier Machian views. (shrink)

This paper is in three sections. The first establishes that Newton, in spite of a well-known passage in a letter to Richard Bentley of 1692, did believe in action at a distance. Many readers may see this merely as an act of supererogation, since it is so patently obvious that he did. However, there has been a long history among Newton scholars of allowing the letter to Bentley to over-ride all of Newton’s other pronouncements in favour of action at a (...) distance, with devastating effects on our understanding of related aspects of his physics and his theology. Furthermore, this misconceived scholarly endeavour shows no sign of abating. The second section then offers a historical reconstruction, based on Newton’s writings, of how, when and why he began to accept actions at a distance and make them one of the cornerstones of his physics. Finally, using this chronological account of Newton’s use of actions at a distance, the paper re-assesses the claims of B. J. T. Dobbs that Newton’s important manuscript, De gravitatione et aequipondio fluidorum, was written, not in the late 1660s or early 1670s as was previously supposed, but during the composition of the Principia, in 1684 or 1685.Keywords: Isaac Newton; Action-at-a-distance; Gravity; Force; Aether; Attraction. (shrink)

ZusammenfassungEs wird die wechselseitige Beeinflussung Einsteins und Schlicks anhand ihrer ab 1915 erhaltenen Korrespondenz in vier Schwerpunkten untersucht. Schlicks Selbstverständnis als Philosoph wie auch einzelne Themata seines Denkens (wie etwa das der Einfachheit) bildeten sich mit seiner Auseinandersetzung um die Relativitätstheorie Einsteins heraus, deren systematische Explikation durch Schlick auf Einsteins Beifall stieß. Als die Ursache für das Auseinanderdriften beider Denker nach 1925 werden fundamentale Differenzen im Wirklichkeitsverständnis und in der Interpretation des Kausalitätsprinzips aufgewiesen, die beide auch zu komplementären Formen der (...) Wissenschaftsgeschichtsbetrachtung führten. (shrink)

In this new edition, Arthur Fine looks at Einstein's philosophy of science and develops his own views on realism. A new Afterword discusses the reaction to Fine's own theory. "What really led Einstein . . . to renounce the new quantum order? For those interested in this question, this book is compulsory reading."--Harvey R. Brown, American Journal of Physics "Fine has successfully combined a historical account of Einstein's philosophical views on quantum mechanics and a discussion of some of the philosophical (...) problems associated with the interpretation of quantum theory with a discussion of some of the contemporary questions concerning realism and antirealism. . . . Clear, thoughtful, [and] well-written."--Allan Franklin, Annals of Science "Attempts, from Einstein's published works and unpublished correspondence, to piece together a coherent picture of 'Einstein realism.' Especially illuminating are the letters between Einstein and fellow realist Schrodinger, as the latter was composing his famous 'Schrodinger-Cat' paper."--Nick Herbert, New Scientist "Beautifully clear. . . . Fine's analysis is penetrating, his own results original and important. . . . The book is a splendid combination of new ways to think about quantum mechanics, about realism, and about Einstein's views of both."--Nancy Cartwright, Isis. (shrink)

ZusammenfassungFasst man die Ψ‐Funktion in der Quantenmechanik als eine vollständige Beschreibung eines realen Sachverhaltes auf, so ist die Hypothese einer schwer annehm‐baren Fernwirkung impliziert. Fasst man die Ψ‐Funktion aber als eine unvollständige Beschreibung eines realen Sachverhaltes auf, so ist es schwer zu glauben, dass für eine unvollständige Beschreibung strenge Gesetze für die zeitliche Abhängigkeit gelten.‐ A. E.

It is argued that Minkowski space-time cannot serve as the deep structure within a ``constructive'' version of the special theory of relativity, contrary to widespread opinion in the philosophical community.

The action-reaction principle (AR) is examined in three contexts: (1) the inertial-gravitational interaction between a particle and space-time geometry, (2) protective observation of an extended wave function of a single particle, and (3) the causal-stochastic or Bohm interpretation of quantum mechanics. A new criterion of reality is formulated using the AR principle. This criterion implies that the wave function of a single particle is real and justifies in the Bohm interpretation the dual ontology of the particle and its associated wave (...) function. But it is concluded that the Bohm theory is not dynamically complete because the particle and its associated wave function do not satisfy the AR principle. (shrink)

Die Relativitatstheorien (RT) Einsteins gehoren zu den meistdiskutierten Theorien der Physik des zwanzigsten Jahrhunderts. Nach der Formulie­ rung der sog. 'speziellen Relativitatstheorie' (SRT) im Jahr 1905 nah­ men zunachst nur einige Spezialisten von ihr Kenntnis, bis mit ungefiihr fiinf Jahren Verspatung dann auch zunehmend Nicht-Physiker sich mit ihr zu beschaftigen begannen, angeregt durch populiirwissenschaftliche, all­ gemeinverstiindliche 'Einfiihrungen' von Kollegen Einsteins wie z. B. Paul Langevin in Frankreich oder Max von Laue in Deutschland. Diese Pha­ senverschiebung zwischen fachwissenschaftlichem Ausbau der Theorie (...) und offentlicher Notiznahme wiederholte sich bei Einsteins 'allgemeiner Theorie der Relativitat und Gravitation' (ART). Zwischen 1913 und 1915 in ihren wesentlichen Ziigen ausformuliert, wurde sie erst nach einer spektakuliiren experimentellen Bestatigung im Jahr 1919 einem breiterem Publikum be­ kannt. In meiner Arbeit werde ich den Facettenreichtum der Ausdeutungen, die beide RT erfuhren, zunachst zu referieren und durch repriisentative Zi­ tate aus der Literatur der Zeit zu belegen haben. Der Umfang dieser Arbeit geht wesentlich auf das Konto dieser ausgewahlten Belege - davon verspre­ che ich mir, dafi nicht nur bislang unveroffentlichte Dokumente, sondern auch entlegene Texte hier in ihren zentralen Passagen leicht zuganglich ge­ macht werden. Fernerhin werde ich aber auch zu analysieren haben, warum derartig vielfaltige, einander mitunter diametral entgegengesetzte Interpre­ tationen einer wissenschaftlichen Theorie vorgelegt wurden. (shrink)

iinstein oered the prin™iple of gener—l ™ov—ri—n™e —s the fund—ment—l physi™—l prin™iple of his gener—l theory of rel—tivityD —nd —s responsi˜le for extending the prin™iple of rel—tivity to —™™eler—ted motionF „his view w—s disputed —lmost immedi—tely with the ™ounterE™l—im th—t the prin™iple w—s no rel—tivity prin™iple —nd w—s physi™—lly v—™uousF „he dis—greeE ment persists tod—yF „his —rti™le reviews the development of iinstein9s thought on gener—l ™ov—ri—n™eD its rel—tion to the found—tions of gener—l rel—tivity —nd the evolution of the ™ontinuing de˜—te (...) over his viewpointF.. (shrink)

It is often claimed that the geodesic principle can be recovered as a theorem in general relativity. Indeed, it is claimed that it is a consequence of Einstein's equation (or of the conservation principle that is, itself, a consequence of that equation). These claims are certainly correct, but it may be worth drawing attention to one small qualification. Though the geodesic principle can be recovered as theorem in general relativity, it is not a consequence of Einstein's equation (or the conservation (...) principle) alone. Other assumptions are needed to drive the theorems in question. One needs to put more in if one is to get the geodesic principle out. My goal in this short note is to make this claim precise (i.e., that other assumptions are needed). (shrink)

Discussions on the nature of reality between Albert Einstein and Rabindranath Tagore, Bengali poet, philosopher and Nobel laureate, have provoked interest among both physicists and philosophers since their first publication in 1930/31. This article points out their relevance to past and present debates about the meaning of quantum mechanics.

Unter Berücksichtigung von Ishiguros Gegenargumenten untersucht dieser Aufsatz erneut die traditionelle Interpretation von Leibniz' These, daß es keine kausale Wechselwirkung zwischen den Substanzen gebe und daß die kausalen Erklärungen für die Eigenschaften einer Substanz völlig in ihrer Natur lägen. Ishiguros Argumente benutzen die Unterscheidung zwischen dem Begriff einer Substanz und ihrer Natur, und in der Tat kann die Philosophie von Leibniz ohne diese Unterscheidung nicht voll gewürdigt werden. Aber sie lassen nicht erkennen, daß für Leibniz keine eindeutige Entsprechung zwischen ihnen (...) besteht. Sie lassen nicht erkennen, daß die kausale Erklärung für die Eigenschaften einer Substanz nicht völlig in ihrer eigenen Natur liegt. Die traditionelle Interpretation der prästabilierten Harmonie wird von allem, was Leibniz sagt, unterstützt und sollte wieder zur Geltung kommen. (shrink)