This paper is devoted to the key ideas of K. F. von Weizsäcker. His book “Aufbau der Physik”, which is dedicated to building a unified physical theory, is in the focus. Confirming that quantum mechanics is a universal physical theory, Weizsäcker is looking for ways to construct it. Based on the logic of temporary statements, introducing the concept of the Uralternative, Weizsäcker comes to the construction of quantum theory. He shows that on its basis the theory of relativity can be obtained, the structure of space with a relational character can be deduced.
This paper is devoted to the key ideas of K. F. von Weizsäcker. His book “Aufbau der Physik”, which is dedicated to building a unified physical theory, is in the focus. Confirming that quantum mechanics is a universal physical theory, Weizsäcker is looking for ways to construct it. Based on the logic of temporary statements, introducing the concept of the Uralternative, Weizsäcker comes to the construction of quantum theory. He shows that on its basis the theory of relativity can be obtained, the structure of space with a relational character can be deduced.
The article is devoted to the problem of time in modern science, where in recent years there have been major changes related to the latest discoveries in the field of the foundations of quantum theory. The author refers to works of K.-F. von Weizsacker (which works are not well-known in Russian-speaking field). Weizsacker deploys a large-scale program of building modern physics, while starting (not only as a physicist, but also a professional philosopher) with questions of philosophical interpretation of postulates of modern physics, especially quantum mechanics. His key thesis is that time in physics is fundamentally distinct, which represents the whole physics as an integral scientific discipline. Weizsacker comes from physical and philosophical reflections, that give a special value to his work. Analyzing the conclusions of theoretical physics, namely the issues of substantiation of statistical mechanics, thermodynamics, and, above all, quantum mechanics, Weizsacker comes to the key idea of the structure of time in the substantiation of physical theory. The author in this conclusion disagrees with the opinion of most modern physicists that time has a subjective character, and the modus of the past, present and future reflects its essential character. The allocation of the time structure requires special logic. Such a logic is temporal and quantum. Starting from temporal logic, introducing the concept of possibility and probability, he comes to the substantiation of quantum mechanics. Being modal logic, it is based on the concept of possibility and probability. Key concept for Weizsacker is a binary alternative (Uralternative), closely related to the principle of superposition in quantum mechanics. By introducing the concept of certain alternatives, essentially actualized alternatives, Weizsacker shows how one can get the theory of relativity with its space-time structure. Further, he shows that based on its structure, you can get the theory of relativity. The space-time structure in this case is secondary, relational, as understood by Leibniz, Mach, and Einstein.
We are interested here in the program of reconstruction of quantum mechanics of the German physicist and philosopher Carl Friedrich von Weizsäcker, which still has some supporters today. In the major part of this article, we limit ourselves to examining purely epistemological and philosophical questions. The theory of the German physicist is often interpreted with reference to Kant, but the most of the time in a rather vague way (categories of understanding, theory of experience). We can afford to be more precise. First we situate the theory of fundamental alternatives (or Ur-alternatives) of von Weizsäcker in the lineage of the Kantian theory of the transcendental Ideal. We then show that the physicist only substitutes for the classical logic, on which Kant relied, a quantum logic allowing to generate, from the alternatives, via the local isomorphism between certain spinor groups and groups linked to space-time, the whole of physical reality to which we have access. After examining some problems, we finally show how this perspective leads to a quantum theory of information.
In this research work the quantum theory of Ur-alternatives of Carl Friedrich von Weizsäcker is considered. In This theory all objects and interactions in nature are constituted by abstract purely quantum logical relations in time. Such structures can be devided into binary alternatives, which are called Ur-Alternatives with respect to this principle meaning, and this leads to a tensor space of many Ur-alternatives. The indistinguishability of the Ur-alternatives yields two Hilbert spaces, the tensor space of symmetric and antisymmetric states under permutations of the Ur-alternatives. It is shown how the structures in the symmetric space can be represented in a three dimensional real position space connected to time according to special relativity. Accordingly this theory obtains ultimately a deep understanding of the EPR-paradox, since logic is independent of topological structures and causal relations in space. The antisymmetric space, which because of the Pauli principle contains much less degress of freedem, yields the additional quantum numbers of the elementary particles. Based on the demand for the highest possible symmetry in the tensor space, the Yang-Mills gauge theories of the standard model as well as a translational gauge formulation of general relativity in a purely quantum logical description are derived. The equations determine entanglements of states containing many Ur-alternatives and this concept is the analogue to classical pointwise interactions between separated objects. This means that the main structures of the SU(N)-interactions of the standard model of elementary particle physics as well as gravitation according to general relativiy are unified in a purely quantum theoretical conceptional framework. Finally it is derived an extended version of the E8-group, the biggest exceptional Lie-group.
The article is devoted to the interpretation of physical knowledge in the works "Structure of Physics" by K. F. von Weizsäcker and “Matter does not exist” by H.-P. Dürr. These works reveal a special understanding of matter in quantum mechanics. In the interpretation of physical knowledge H.-P. Dürr and K. F. von Weizsäcker postulate a special interpretation of matter within the framework of quantum theory, namely the inseparability of consciousness from matter. At the same time, we emphasize the fundamental difference between these approaches. H.-P. Dürr remains in the position of Advaita-Vedanta, his approach is closer to Eastern metaphysics, Weizsäcker adheres to the Western epistemological tradition, presenting physics as what we can know about matter. Heidegger also touches this issue, he criticizes the concept of "object" and "subject" in modern science, but does not say that both concepts must somehow be combined.
The quantum theory of Ur-alternatives of Carl Friedrich von Weizsaecker tries to constitute general quantum theory based on the concept of logical alternatives in time. Based on this interpretation of quantum theory the existence of free objects in space, their symmetry properties and their interactions shall be inferred. The alternatives are represented by binary alternatives, which are called Ur-alternatives because of their logically fundamental character. Through Ur-alternatives as elementary quantum theoretical units of information the Copernican revolution with respect to the question of space is realized in a consequent way. This means that not the objects of nature are in a given space, but the existence of space arises as a kind of indirect representation of relations between abstract quantum theoretical objects. The Ur-alternatives do not exist in a given physical reality, but the existence of space is constituted by Ur-alternatives at all. Such a concept of reality is implicitly contained within the uncertainty relation and can be seen especially in the EPR-paradoxon. It is shown in this thesis in a mathematical consistent way that a state in the tensor space of many Ur-alternatives can directly be mapped into a real three dimensional space which means that together with the dynamics a representation in a (3+1)-dimensional space-time becomes possible. By considering the G2 an approach for the incorporation of the internal symmetries can be suggested. Furthermore the Ur-alternatives enable the constitution of a concept of interaction, which is based on quantum theoretical entanglement. By using this concept it is tried to obtain a purely quantum theoretical description of electromagnetism and gravity. This corresponds to a much more principle and in a radical sense background independent way of quantization.
The development of the logical and mathematical foundations of quantum physics and, first of all, quantum mechanics is the work of a large team of physicists, mathematicians and philosophers who have contributed to the solution of this problem. The title of the article lists the names of four scientists who, according to the author, paved the way for the creation of quantum logic. This must be understood in such a way that from the very beginning (Heisenberg and Schrödinger) it was established that the properties of quantum objects are described not by numbers, but by operators. In the relationships of the operators themselves, one could see an analogue of Boolean algebra of classical logic. Weizsäcker raised the question of how the physical quantity of time, in describing the motion states of quantum objects, can be represented: an operator or a state vector? The author of the article shows that the development of quantum mechanics has gone through two stages. The first stage differs in that complex numbers and functions were introduced into physics, in other words, elements of the theory of functions of a complex variable. At the second stage, spinor calculus penetrated into quantum physics. If at the first stage methods were presented for describing the external degrees of freedom (motion) of elementary particles and other quantum objects, then the second stage was marked by the description of internal degrees of elementary particles. It became possible to understand that the measured mass of an electron or any other fermion is an averaged quantity, it consists of two ingredients: a positive mass and a negative mass (two values of the corresponding operator). An important role in this discovery played the operation of dialectical negation (privation), borrowed from Heidegger's fundamental ontology.