arXiv subjects
Publications and source records attributed to Giovanni Zanella.
In order to respect the Principle of Relativity, the analysis of the behavior of the longitudinal light clock reveals the necessity to extend the Doppler effect also to space and time. As a consequence, the bodies in inertial motion must dilate along the direction of their movement.
The efficiency of a radiation detector, intended as probability of detection of an incident quantum, depends on various factors: the detected fraction of quanta ascribed to the noise-less detector, the intrinsic noise of the detector, the false events introduced by the detection process and the false events generated by the detector itself. In this paper is treated the role of the false events on the measurement of the detective quantum efficiency (DQE) of the radiation detectors, indifferently for counting detectors and imaging detectors.
The properties of the light, the Lorentz transformations and the relation mass-energy are introduced using the wave picture of the light and of the massive particles.
This paper shows as the relativistic Doppler effect can be extended also to time and space associated to moving bodies. This extension derives from the analysis of the wave-fronts of the light emitted by a moving source in inertial motion in the empty space, as viewed from the stationary reference. Indeed, time and space can be represented by the same vector quantities, which appear asymmetrical in forward and back direction along the path of the moving body. Consequently, the whole size of the moving bodies dilates along the direction of their motion, as their path. Thought experiments and real facts demonstrate this issue.
The wave nature of the light, applied to the kinematics of the moving bodies, permits to investigate and find a coherent solution on some questions raised by the theory of special relativity about the Lorentz contraction.
The usual interpretation of noise is represented by a sum of many independent two-level elementary random signals with a distribution of relaxation times. In this paper it is demonstrated that also the superposition of many similar single-sided two-level signals, with the same relaxation time, produces noise. This is possible tanks to the coincidences among the signals which introduce cross-correlations and tune locally the resulting process in trains of pseudo-periodic pulses. Computer simulations demonstrate the reliability of this model, which permits to insert in an coherent framework other models solving problems still open.
In this paper it is demonstrated that 1/f power spectrum appears in the process originated by the superposition of many single-sided random telegraph signals (RTS or RTN) with the same amplitude, probability and relaxation time. Indeed, the coincidences of these RTSs generate self-organizing fluctuations which are responsible for the generation of 1/f noise under various aspects. The accord of the exposed model with other models and with various experimental results is displayed.
In this paper it is demonstrated that a 1/f power spectrum appears in the process originated by the superposition of many similar single-sided RTN processes with the same relaxation time. The non-relaxed regime, the Gaussian nature and the average periodicity of the resulting fluctuation, are responsible for the generation of 1/f noise, thanks to the coincidences of these RTN processes. The decomposition of the resulting fluctuation, in a set of further single-sided RTN processes with a distribution of relaxation times, permits us to demonstrate once more the generation of the 1/f noise.
A general physical model is presented for 1/f noise. The main questions raised by this type of noise can be solved if at the origin of the phenomenon we consider many similar like RTN two-state processes in co-operation among them to generate a Gaussian average process with 1/f power spectrum. Even if the originating RTN processes have the same relaxation time, their co-operation produces in short times secondary RTN processes with a distribution of relaxation times which generates again 1/f noise. An extension of the model to a single two-state process viewed in "series" reveals once more the appearance of 1/f noise. Experimental results, found in the literature, agree with this model under various aspects.
In this paper a general and unified treatment of the DQE is exposed, both in the space-domain and in the frequency-domain. The meaning of the DQE as quantum efficiency appears to be of paramount importance for a correct interpretation of the physical parameters involved in its formulation and measurement. The treatment in the frequency-domain turns out to be a direct extension of that in the space-domain. An operational procedure is introduced to consider the effect of the filtering of the detector in the space-domain.