Huning: Ingenieurausbildung und soziale Verantwortung/Kilmister: General Theory of Relativity/Urban: Recent Developments in Mathematical Physics/Velo: Constructive Quantum Field Theory/Ballif: Anschauliche Physik/Schnell: Magnete/Hauffe: Adsorption/Schnei

The following paper presents a description on the fundamental mechanics of nature.This is the first of a set of papers entitled Foundations of fundamental mechanics, in which this first paper is specifically on the nature of gravity.For all intents and purposes this paper is NOT intended to be a replacement for the General theory of Relativity (GR) (A. Einstein 1915–1916), rather it is intended to be a complimentary extension of its work, with the purpose of extending it into quantum physics. Most notably, to relate it to quantum field theory (QFT), by quantizing the metric of space-time into a potential field theory.

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On the feasibility of charged wormholes

Open Physics ◽

10.2478/s11534-011-0043-2 ◽

2011 ◽

Vol 9 (5) ◽

Cited By ~ 3

Author(s):

Peter Kuhfittig

Keyword(s):

Field Theory ◽

Quantum Field Theory ◽

General Theory ◽

Quantum Field ◽

Theory Of Relativity ◽

Extended Version ◽

General Theory Of Relativity ◽

Fields Equations

AbstractWhile wormhole spacetimes are predictions of the general theory of relativity, specific solutions may not be compatible with quantum field theory. This paper modifies the charged wormhole model of Kim and Lee with the aim of satisfying an extended version of a quantum inequality due to Ford and Roman. The modified metric may be viewed as a solution of the Einstein fields equations representing a charged wormhole that is compatible with quantum field theory.

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A New Approach to Quantum Gravity

Global Journal of Science Frontier Research ◽

10.34257/gjsfravol20is2pg1 ◽

2020 ◽

pp. 1-15

Author(s):

Gang Lee

Keyword(s):

Field Theory ◽

Quantum Field Theory ◽

Gravitational Field ◽

Field Equation ◽

General Theory ◽

Feynman Integral ◽

Quantum Field ◽

Theory Of Relativity ◽

General Theory Of Relativity ◽

New Approach

In this paper, we introduce a different approach to the theory of gravitational field. This method can give the semiclassical graviton directly. We discuss the dynamics and quantization of graviton and obtain the field equation of graviton. Also we give proof to prove that the quantum field theory constructed in this paper is classically equivalent to the general theory of relativity. We obtain the Green’s function of the graviton by the field equation, and the difficulty of Feynman integral divergence can be solved by this method.

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We have confidence to lead gravitational-wave science: an interview with Yueliang Wu

National Science Review ◽

10.1093/nsr/nwx072 ◽

2017 ◽

Vol 4 (5) ◽

pp. 718-720

Author(s):

Hepeng Jia

Keyword(s):

Field Theory ◽

Quantum Field Theory ◽

Gravitational Wave ◽

Theoretical Physics ◽

Quantum Field ◽

Theory Of Relativity ◽

General Theory Of Relativity ◽

Chinese Academy Of Sciences ◽

Wave Research ◽

Academy Of Sciences

Abstract Yueliang Wu, chief scientist of Taiji Program, is a well-known theoretical physicist and the Vice-President of the University of Chinese Academy of Sciences (UCAS). Taiji Program, initially proposed in 2008, is one of China's ambitious plans to observe gravitational waves. Obtaining his Ph.D. at the Institute of Theoretical Physics (ITP) under the Chinese Academy of Sciences (CAS) in 1987, Wu had been working at Dortmund University and Mainz University in Germany and Carnegie-Mellon University and the Ohio-State University in the USA. In 1996, he joined the ITP and became its director in 2007. He has also served as the Director of the Kavli Institute for Theoretical Physics China at the CAS since 2006. In 2007, he was elected as a CAS member. Wu's research is focused on elementary particle physics, quantum field theory, symmetry principle and cosmophysics. In recent years, he has been proposing a gravitational quantum field theory as a new approach to reconciling the general theory of relativity and quantum mechanics. The most fundamental unanswered question of the general theory of relativity is how general relativity can be reconciled with the laws of quantum physics to produce a complete and self-consistent theory of quantum gravity. To extend the general relativity to realize the reconciliation, Wu suggested a basic gravitational field be needed in the future model. Since 2012, he, together with Wenrui Hu, has been working as Taiji Program's chief scientist and promoting nationwide gravitational-wave research. National Science Review (NSR) spoke with Wu about the future of gravitational-wave research, the development of China's nationwide gravitational-wave studies and particularly the progress of Taiji Program.

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Classification of quantum states based on the null energy condition

Modern Physics Letters A ◽

10.1142/s0217732321501832 ◽

2021 ◽

Vol 36 (25) ◽

pp. 2150183

Author(s):

Susobhan Mandal

Keyword(s):

Field Theory ◽

Quantum Field Theory ◽

Coherent States ◽

Energy Condition ◽

Null Energy Condition ◽

Quantum States ◽

Quantum Field ◽

Theory Of Relativity ◽

General Theory Of Relativity

Violation of the null energy condition plays an important role both in the general theory of relativity and quantum field theory in curved spacetimes. Over the years, it has been shown that the violation of the null energy condition leads to instability and violation of causality. In quantum field theory, violation of the energy condition also depends on the quantum states apart from the geometry of curved spacetime. Hence, the quantum effects play an important role in the violation of the null energy condition. We show that the set of all the coherent states does not violate the null energy condition. Further, we also show that under certain conditions, the null energy condition is violated either by a pure state or a mixed state. Furthermore, the dynamical violation of the null energy condition by the quantum states is also discussed here.

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Albert Einstein’s Epistemic Virtues and Vices

Epistemology & Philosophy of Science ◽

10.5840/eps202158468 ◽

2021 ◽

Vol 58 (4) ◽

pp. 175-195

Author(s):

Vladimir P. Vizgin ◽

Keyword(s):

Field Theory ◽

General Relativity ◽

General Theory ◽

Special Theory ◽

Theory Of Relativity ◽

Mathematical Aspect ◽

General Theory Of Relativity ◽

Special Theory Of Relativity ◽

Epistemic Virtues ◽

The Universe

The article is based on the concepts of epistemic virtues and epistemic vices and explores A. Einstein’s contribution to the creation of fundamental physical theories, namely the special theory of relativity and general theory of relativity, as well as to the development of a unified field theory on the basis of the geometric field program, which never led to success. Among the main epistemic virtues that led Einstein to success in the construction of the special theory of relativity are the following: a unique physical intuition based on the method of thought experiment and the need for an experimental justification of space-time concepts; striving for simplicity and elegance of theory; scientific courage, rebelliousness, signifying the readiness to engage in confrontation with scientific conventional dogmas and authorities. In the creation of general theory of relativity, another intellectual virtue was added to these virtues: the belief in the heuristic power of the mathematical aspect of physics. At the same time, he had to overcome his initial underestimation of the H. Minkowski’s four-dimensional concept of space and time, which has manifested in a distinctive flexibility of thinking typical for Einstein in his early years. The creative role of Einstein’s mistakes on the way to general relativity was emphasized. These mistakes were mostly related to the difficulties of harmonizing the mathematical and physical aspects of theory, less so to epistemic vices. The ambivalence of the concept of epistemic virtues, which can be transformed into epistemic vices, is noted. This transformation happened in the second half of Einstein’s life, when he for more than thirty years unsuccessfully tried to build a unified geometric field theory and to find an alternative to quantum mechanics with their probabilistic and Copenhagen interpretation In this case, we can talk about the following epistemic vices: the revaluation of mathematical aspect and underestimation of experimentally – empirical aspect of the theory; adopting the concepts general relativity is based on (continualism, classical causality, geometric nature of fundamental interactions) as fundamental; unprecedented persistence in defending the GFP (geometrical field program), despite its failures, and a certain loss of the flexibility of thinking. A cosmological history that is associated both with the application of GTR (general theory of relativity) to the structure of the Universe, and with the missed possibility of discovering the theory of the expanding Universe is intermediate in relation to Einstein’s epistemic virtues and vices. This opportunity was realized by A.A. Friedmann, who defeated Einstein in the dispute about if the Universe was stationary or nonstationary. In this dispute some of Einstein’s vices were revealed, which Friedman did not have. The connection between epistemic virtues and the methodological principles of physics and also with the “fallibilist” concept of scientific knowledge development has been noted.

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A UNIFIED FORMALISM OF THERMAL QUANTUM FIELD THEORY

International Journal of Modern Physics A ◽

10.1142/s0217751x94000960 ◽

1994 ◽

Vol 09 (14) ◽

pp. 2363-2409 ◽

Cited By ~ 37

Author(s):

H. CHU ◽

H. UMEZAWA

Keyword(s):

Field Theory ◽

Quantum Field Theory ◽

Vacuum Polarization ◽

Time Dependent ◽

Quantum Field ◽

Bogoliubov Transformation ◽

Transformation Matrices ◽

Thermo Field Dynamics ◽

The Matrix ◽

Recent Developments

We present a comprehensive review of the most fundamental and practical aspects of thermo-field dynamics (TFD), including some of the most recent developments in the field. To make TFD fully consistent, some suitable changes in the structure of the thermal doublets and the Bogoliubov transformation matrices have been made. A close comparison between TFD and the Schwinger-Keldysh closed time path formalism (SKF) is presented. We find that TFD and SKF are in many ways the same in form; in particular, the two approaches are identical in stationary situations. However, TFD and SKF are quite different in time-dependent nonequilibrium situations. The main source of this difference is that the time evolution of the density matrix itself is ignored in SKF while in TFD it is replaced by a time-dependent Bogoliubov transformation. In this sense TFD is a better candidate for time-dependent quantum field theory. Even in equilibrium situations, TFD has some remarkable advantages over the Matsubara approach and SKF, the most notable being the Feynman diagram recipes, which we will present. We will show that the calculations of two-point functions are simplified, instead of being complicated, by the matrix nature of the formalism. We will present some explicit calculations using TFD, including space-time inhomogeneous situations and the vacuum polarization in equilibrium relativistic QED.

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Universal bounds for large determinants from non-commutative Hölder inequalities in fermionic constructive quantum field theory

Mathematical Models and Methods in Applied Sciences ◽

10.1142/s0218202517500361 ◽

2017 ◽

Vol 27 (10) ◽

pp. 1963-1992 ◽

Cited By ~ 3

Author(s):

J.-B. Bru ◽

W. de Siqueira Pedra

Keyword(s):

Field Theory ◽

Quantum Field Theory ◽

Von Neumann Algebras ◽

Perturbation Expansion ◽

Perturbation Series ◽

Interparticle Interaction ◽

Quantum Field ◽

Von Neumann ◽

Constructive Quantum Field Theory ◽

Strength Formula

Efficiently bounding large determinants is an essential step in non-relativistic constructive quantum field theory to prove the absolute convergence of the perturbation expansion of correlation functions in terms of powers of the strength [Formula: see text] of the interparticle interaction. We provide, for large determinants of fermionic covariances, sharp bounds which hold for all (bounded and unbounded, the latter not being limited to semibounded) one-particle Hamiltonians. We find the smallest universal determinant bound to be exactly [Formula: see text]. In particular, the convergence of perturbation series at [Formula: see text] of any fermionic quantum field theory is ensured if the matrix entries (with respect to some fixed orthonormal basis) of the covariance and the interparticle interaction decay sufficiently fast. Our proofs use Hölder inequalities for general non-commutative [Formula: see text]-spaces derived by Araki and Masuda [Positive cones and [Formula: see text]-spaces for von Neumann algebras, Publ. RIMS[Formula: see text] Kyoto Univ. 18 (1982) 339–411].

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