The evolution of gravitational tests from an epistemological perspective framed in the concept of rational reconstruction of Imre Lakatos, based on his methodology of research programmes. Unlike other works on the same subject, the evaluated period is very extensive, starting with Newton's natural philosophy and up to the quantum gravity theories of today. In order to explain in a more rational way the complex evolution of the gravity concept of the last century, I propose a natural extension of the methodology (...) of the research programmes of Lakatos that I then use during the paper. I believe that this approach offers a new perspective on how evolved over time the concept of gravity and the methods of testing each theory of gravity, through observations and experiments. I argue, based on the methodology of the research programmes and the studies of scientists and philosophers, that the current theories of quantum gravity are degenerative, due to the lack of experimental evidence over a long period of time and of self-immunization against the possibility of falsification. Moreover, a methodological current is being developed that assigns a secondary, unimportant role to verification through observations and/or experiments. For this reason, it will not be possible to have a complete theory of quantum gravity in its current form, which to include to the limit the general relativity, since physical theories have always been adjusted, during their evolution, based on observational or experimental tests, and verified by the predictions made. Also, contrary to a widespread opinion and current active programs regarding the unification of all the fundamental forces of physics in a single final theory, based on string theory, I argue that this unification is generally unlikely, and it is not possible anyway for a unification to be developed based on current theories of quantum gravity, including string theory. In addition, I support the views of some scientists and philosophers that currently too much resources are being consumed on the idea of developing quantum gravity theories, and in particular string theory, to include general relativity and to unify gravity with other forces, as long as science does not impose such research programs. -/- DOI: 10.13140/RG.2.2.35350.70724 . (shrink)

Evoluția testelor gravitaționale dintr-o perspectivă epistemologică încadrată în conceputul de reconstrucție rațională al lui Imre Lakatos, pe baza metodologiei acestuia a programelor de cercetare. Perioada evaluată este foarte vastă, începând cu filosofia naturală a lui Newton și până la teoriile gravitației cuantice din zilele noastre. Pentru a explica mai rațional evoluția complexă a conceptului de gravitație din ultimul secol, propun o extindere naturală a metodologiei programelor de cercetare pe care o folosesc apoi pe parcursul lucrării. Consider că această abordare oferă (...) o nouă perspectivă asupra modului în care au evaluat în timp conceptul de gravitație și metodele de testare a fiecărei teorii a gravitației, prin observații și experimente. Argumentez, pe baza metodologiei programelor de cercetare și a studiilor oamenilor de știință și filosofilor, că actualele teorii ale gravitației cuantice sunt degenerative, datorită lipsei dovezilor experimentale pe o perioadă îndelungată de timp și a auto-imunizării împotriva posibilității falsificării. Mai mult, în prezent este în curs de dezvoltare un curent metodologic care atribuie un rol secundar, neimportant, verificărilor prin observații și/sau experimente. Din această cauză, nu va fi posibilă o teorie completă a gravitației cuantice în forma actuală care să includă la limită relativitatea generală, întrucât teoriile fizice au fost dintotdeauna ajustate, în decursul evoluției lor, pe baza testelor observaționale sau experimentale, și verificate prin predicțiile făcute. De asemenea, contrar unei opinii răspândite și a unor programe active actuale privind unificarea tuturor forțelor fundamentale ale fizicii într-o singură teorie finală, pe baza teoriei corzilor, argumentez că este puțin probabil în general să se realizeze această unificare, și nu este posibil oricum ca unificarea să se elaboreze pe baza teoriilor actuale ale gravitației cuantice, inclusiv prin teoria corzilor. În plus, susțin punctele de vedere ale unor oameni de știință și filosofi că în prezent se consumă mult prea multe resurse pe ideea dezvoltării teoriilor gravitației cuantice, și în special teoria corzilor, care să includă relativitatea generală și să unifice gravitația cu celelalte forțe, în condițiile în care știința nu impune astfel de programe de cercetare. -/- DOI: 10.13140/RG.2.2.14582.75842 . (shrink)

General Relativity generated various early philosophical interpretations. His adherents have highlighted the "relativization of inertia" and the concept of simultaneity, Kantians and Neo-Kantians have underlined the approach of certain synthetic "intellectual forms" (especially the principle of general covariance, and logical empirics have emphasized the philosophical methodological significance of the theory. Reichenbach approached the GR through the "relativity of geometry" thesis, trying to build a "constructive axiomatization" of relativity based on "elementary matters of fact" (Elementartatbestande) for the observable behavior of light (...) rays, rods and clocks. The mathematician Hermann Weyl attempted a reconstruction of Einstein's theory based on the epistemology of a "pure infinitesimal geometry", an extended geometry with additional terms that formally identified with the potential of the electromagnetic field. DOI: 10.13140/RG.2.2.11641.93281. (shrink)

Ernst Cassirer, 2011, Symbolische Prägnanz, Ausdrucksphänomen und „Wiener Kreis“, Nachgelassene Manuskripte und Texte, vol. 4, ed. Christian Möckel, 478pp., Hamburg, Felix Meiner Verlag.

One of the key events in the relations between the Central European philosophers and those of the Nordic countries was the Second International Congress for the ...

The aim of this paper is make a contribution to the ongoing search for an adequate concept of the a priori element in scientific knowledge. The point of departure is C.I. Lewis’s account of a pragmatic a priori put forward in his "Mind and the World Order" (1929). Recently, Hasok Chang in "Contingent Transcendental Arguments for Metaphysical Principles" (2008) reconsidered Lewis’s pragmatic a priori and proposed to conceive it as the basic ingredient of the dynamics of an embodied scientific reason. (...) The present paper intends to further elaborate Chang’s account by relating it with some conceptual tools from cognitive semantics and certain ideas that first emerged in the context of the category-theoretical foundations of mathematics. (shrink)

Pierre Duhem's often unrecognized influence on twentieth-century philosophy of science is illustrated by an analysis of his significant if also largely unrecognized influence on Albert Einstein. Einstein's first acquaintance with Duhem's La Théorie physique, son objet et sa structure around 1909 is strongly suggested by his close personal and professional relationship with Duhem's German translator, Friedrich Adler. The central role of a Duhemian holistic, underdeterminationist variety of conventionalism in Einstein's thought is examined at length, with special emphasis on Einstein's deployment (...) of Duhemian arguments in his debates with neo-Kantian interpreters of relativity and in his critique of the empiricist doctrines of theory testing advanced by Schlick, Reichenbach, and Carnap. Most striking is Einstein's 1949 criticism of the verificationist conception of meaning from a holistic point of view, anticipating by two years the rather similar, but more famous criticism advanced independently by Quine in Two Dogmas of Empiricism. (shrink)

Cassirer’s neo-Kantian epistemology has become a classical reference in contemporary history and philosophy of science. However, the historical aspects of his thought are sometimes seen to be in some tension with his defence of a priori elements of knowledge. This paper reconsiders Cassirer’s strategy to address this tension by positing functional dependencies at the core of the notion of objectivity. This requires the epistemologist to account for the determination of the objects of knowledge within given scientific theories, but also for (...) conceptual changes over time. (shrink)

Relativitatea generală a generat diverse interpretări filosofice timpurii. Adepții lui au evidențiat "relativizarea inerției" și conceptul de simultaneitate, kantienii și neo-kantienii au subliniat abordarea anumitor "forme intelectuale" sintetice (în special principiul covarianței generale, iar empiriștii logici au accentuat semnificația filozofică metodologică a teoriei. Reichenbach a abordat relativitatea generală prin prisma tezei "relativității geometriei", încercând o "axiomatizare constructivă" a teoriei relativității pe baza "problemelor elementare de fapt" (Elementaratbestande) cu privire la comportamentul observabil al razelor de lumină, a tijelor și a ceasurilor. (...) DOI: 10.13140/RG.2.2.27826.76486. (shrink)

Singularitățile la care se ajunge în relativitatea generală prin rezolvarea ecuațiilor lui Einstein au fost și încă mai sunt subiectul a numeroase dezbateri științifice: Există sau nu, singularități? Big Bang a fost o singularitate inițială? Dacă singularitățile există, care este ontologia acestora? Este teoria generală a relativității o teorie care și-a arătat limitele în acest caz? În acest eseu argumentez faptul că există singularități, iar teoria generală a relativității, ca de altfel oricare altă teorie științifică din prezent, nu este valabilă (...) în interiorul orizontului evenimentelor. Dar asta nu presupune, așa cum consideră unii oameni de știință, că ea trebuie considerată ca fiind perimată. După o scurtă prezentare a aspectelor specifice din teoria clasică newtoniană și teoria specială a relativității, și o scurtă prezentare a teoriei generale a relativității, în capitolul Ontologia relativității generale prezint aspectele ontologice specifice relativității generale. Următorul capitol, Singularități, este dedicat prezentării singularităților care rezultă în relativitatea generală, a aspectelor specifice ale găurilor negre și orizontul evenimentelor, inclusiv dezbaterea despre Big Bang ca singularitate inițială, și argumentele în favoarea existenței singularităților. În Ontologia singularităților vorbesc despre posibilitățile de încadrare ontologică a singularităților în general și a găurilor negre în special, despre argumentul găurii pus în evidență de Einstein, și argumentele prezentate de oamenii de știință că nu există singularități și deci că teoria generală a relativității este în impas. Închei cu Concluziile în care expun și reiau pe scurt argumentele care ămi susțin opiniile prezentate mai sus. Aceasta este o traducere din limba engleză a lucrării: Sfetcu, Nicolae, "The singularities as ontological limits of the general relativity". (shrink)

The singularities from the general relativity resulting by solving Einstein's equations were and still are the subject of many scientific debates: Are there singularities in spacetime, or not? Big Bang was an initial singularity? If singularities exist, what is their ontology? Is the general theory of relativity a theory that has shown its limits in this case? In this essay I argue that there are singularities, and the general theory of relativity, as any other scientific theory at present, is not (...) valid for singularities. But that does not mean, as some scientists think, that it must be regarded as being obsolete. After a brief presentation of the specific aspects of Newtonian classical theory and the special theory of relativity, and a brief presentation of the general theory of relativity, the chapter Ontology of General Relativity presents the ontological aspects of general relativity. The next chapter, Singularities, is dedicated to the presentation of the singularities resulting in general relativity, the specific aspects of the black holes and the event horizon, including the Big Bang debate as original singularity, and arguments for the existence of the singularities. In Singularity Ontology, I am talking about the possibilities of ontological framing of singularities in general and black holes in particular, about the hole argument highlighted by Einstein, and the arguments presented by scientists that there are no singularities and therefore that the general theory of relativity is in deadlock. In Conclusions I outline and summarize briefly the arguments that support my above views. -/- DOI: 10.58679/TW62329. (shrink)

Kantian philosophy of space, time and gravity is significantly affected in three ways by particle physics. First, particle physics deflects Schlick’s General Relativity-based critique of synthetic a priori knowledge. Schlick argued that since geometry was not synthetic a priori, nothing was—a key step toward logical empiricism. Particle physics suggests a Kant-friendlier theory of space-time and gravity presumably approximating General Relativity arbitrarily well, massive spin-2 gravity, while retaining a flat space-time geometry that is indirectly observable at large distances. The theory’s roots (...) include Seeliger and Neumann in the 1890s and Einstein in 1917 as well as 1920s–1930s physics. Such theories have seen renewed scientific attention since 2000 and especially since 2010 due to breakthroughs addressing early 1970s technical difficulties. Second, particle physics casts additional doubt on Friedman’s constitutive a priori role for the principle of equivalence. Massive spin-2 gravity presumably should have nearly the same empirical content as General Relativity while differing radically on foundational issues. Empirical content even in General Relativity resides in partial differential equations, not in an additional principle identifying gravity and inertia. Third, Kant’s apparent claim that Newton’s results could be known a priori is undermined by an alternate gravitational equation. The modified theory has a smaller symmetry group than does Newton’s. What Kant wanted from Newton’s gravity is impossible due its large symmetry group, but is closer to achievable given the alternative theory. (shrink)

The idea that a serious threat to scientific realism comes from unconceived alternatives has been proposed by van Fraassen, Sklar, Stanford and Wray among others. Peter Lipton's critique of this threat from underconsideration is examined briefly in terms of its logic and its applicability to the case of space-time and particle physics. The example of space-time and particle physics indicates a generic heuristic for quantitative sciences for constructing potentially serious cases of underdetermination, involving one-parameter family of rivals T_m that work (...) as a team rather than as a single rival against default theory T_0. In important examples this new parameter has a physical meaning and makes a crucial _conceptual_ difference, shrinking the symmetry group and in some case putting gauge freedom, formal indeterminism vs. determinism, the presence of the hole argument, etc., at risk. Methodologies akin to eliminative induction or tempered subjective Bayesianism are more demonstrably reliable than the custom of attending only to "our best theory": they can lead either to a serious rivalry or to improved arguments for the favorite theory. The example of General Relativity vs. massive spin 2 gravity, a recent topic in the physics literature, is discussed. Arguably the General Relativity and philosophy literatures have ignored the most serious rival to General Relativity. (shrink)

A la teoría de la relatividad se la ha considerado una teoría empírica. Sobre esta interpretación se ha preconizado el triunfo del empirismo sobre cualquier otra concepción filosófica. Moritz Schlick vaticinó que no se podrían encontrar los principios sintéticos a priori de esta ciencia porque tal cosa no existía. Este artículo demuestra no ya sólo que se pueden encontrar, sino que ya estaban en posesión de Kant. La introducción de algunas pocas precisiones nos bastará para adaptar a la teoría de (...) la relatividad tan preciados principios. (shrink)

Matthias Neuber’s book represents an important contribution to the relatively young discipline of the History of Philosophy of Science. Starting roughly in the 1980s, increasing attention has been devoted not only to the relationship between philosophy and the history of science, but to an accurate historical reconstruction of earlier projects within philosophy of science. One of the most outstanding results of these investigations has probably been the radical reshaping of the rather caricatural image of logical empiricism—for better or worse the (...) core of the philosophical heritage of many philosophers of science—summarized in the so-called ‘standard view’. By analyzing the historical, sociological, and philosophical questions surrounding logical empiricism new light has been shed on the sense of a cultural, social, and political mission that characterized it before its emigration from Europe to North America in the 1930s and 1940s. What came to be known as .. (shrink)

Such are those thick & gloomie shadows dampe Oft seene in charnel vaults, & sepulchers, Lingering, & sitting by a new made grave, As loath to leave the bodie that it lov'd, & link’t it selfe by carnall sensualtie To a degenerate, & degraded state.

Despite a renewed interest in the philosophical prehistory of logical empiricism, several texts by prominent figures such as, e.g., Moritz Schlick and Hans Reichenbach, published in non-standard journals, have escaped the notice of scholars. Here, a hitherto virtually unknown but significant review of Moritz Schlick's influential book Allgemeine Erkenntnislehre [1st ed. 1918] written by Hans Reichenbach in 1919/20 is reprinted together with comments about its background and the later development, relying on and citing from the unpublished correspondence between Schlick and (...) Reichenbach in 1920. Since they later became the leading figures in the so called Vienna and Berlin circles respectively, this episode marks an important stage in the gradual emancipation of scientific philosophy from its Kantian roots. (shrink)