Abstract

In quantum theory, objects are intrinsically evolving and changing based on the Uncertainty Principle, and the particle state is described by a time-dependent wave packet such that the wave packet corresponding to even a free particle is successively evolvable; a quantum particle has an indefinite and transformative state. In the relativistic Quantum Fields Theory, instead of the concepts of particle and wave packet, a continuous object named “field” with permanent fluctuation in its ground state is considered as the original concept. In Mulla Sadra’s philosophy, based on the Substantial Motion Theory, the subject of continuous evolution and change in the natural body appears as the intrinsic mobility of the natural body. In this paper, we are going to present a comparative investigation of this topic in the two areas of study mentioned. Initially, we present some necessary topics in physics including the motion of fundamental particles, the motion of quantum objects, Quantum Fields Theory, quantum vacuum, and the creation and annihilation of particles in the Quantum Fields Theory; then, we consider some necessary topics in some fields of study in philosophy about the natural body and the nature and the identity of physical bodies including the ideas and the special opinion of Mulla Sadra. Particularly and with more detail, we pay attention to the Sadrian philosophy about the evolution and intrinsic mobility of the natural body based on his famous Substantial Motion Theory. With a comparative study, and by considering Sadrian philosophy as the fundamental philosophical basis for natural sciences, particularly physics, we try to compare the intrinsic motion of natural bodies in Mulla Sadra’s philosophy with the intrinsic evolution of quantum objects in modern physics. Our research method is based on and uses standard resources including books and research papers about Mulla Sadra’s thoughts and theories and the internationally well-known books and papers on standard quantum physics and quantum fields theory. The conclusive remarks are as follows: The transformation of quantum particles or the creation and annihilation of particles in the theory of quantum fields agrees with this point that the intrinsic mobility of the natural body in Mulla Sadra’s philosophy doesn’t reason on the philosophical existence and/or loss of existence. That a quantum particle doesn’t have a constant status in two consecutive instants is in agreement with the Sadrian Substantial Motion Theory that explains ‘motion’ in the ‘bed’ of time. Finally, we should mention that although the intrinsic motion of the natural body in Mulla Sadra’s philosophy is based on its completion while the creation and annihilation of particles in Quantum Fields Theory may be better compared with the emergence and extinction well known in peripatetic philosophy, by considering the background quantum vacuum field as the main basis of the so-called “particles” which is continuously in evolution and permanent fluctuation and is the basis for the creation and annihilation of particles, the comparison between the modern Quantum Fields Theory and Mulla Sadra’s philosophy is done well.