Based on a model of quantum measurement we derive an estimate for the external measurement-time. Some interesting consequences will be analyzed. Keywords: Quantum Entropy, Energy, Measurement, Time MSC 2000 codes: 94A17, 81P15 Entropy 2006, 8, 182-187 183 1 Introduction Given an apparatus or memory A, a system S and the environment E , the measurement process M can be represented by the followi...

The measurement of short reverberation times poses different problems depending at the same time on difficulties of measurement and the sensitivity of the analysis techniques applicable to short signals. This article presents a toolbox, which allows a reliable estimation of reverberation time for small spaces, in a software environment, and using a lightweight system, designed for in-situ measu...

We present a definition of time measurement based on high energy photons and the fundamental length scale and show that, for macroscopic time, it is in accord with the Lorentz transformation of special relativity. To do this we define observer in a different way than in special relativity.