Causality and the speed of sound
نویسنده
چکیده
A usual causal requirement on a viable theory of matter is that the speed of sound be at most the speed of light. In view of various recent papers querying this limit, the question is revisited here. We point to various issues confronting theories that violate the usual constraint.
منابع مشابه
A new generalized model for predict speed of sound of refrigerants
In consideration of physical and chemical properties of pure substances, speed of sound is one of important quantity which can used to calculate many of other thermo-physical properties such as isothermal compressibility, Joule-Thomson coefficient, isobaric heat capacity and etc. These thermo-physical properties are the main parameters in industrial and chemical processes. Development of accura...
متن کاملDensity and Speed of Sound of Diethylene Glycol Monoethyl Ether + Propylene Glycol at T = (288.15–318.15) K
Thedensity(ρ) and speed of sound (u)of the binarymixture (diethylene glycol monoethyl ether (carbitol) + propylene glycol (PG)) have been reported at T= (288.15, 298.15, 308.15 and 318.15) K. The excess molar volume ( ) and isentropic compressibility deviation (Δκs) were calculated using the measured data. The obtained values of ( ) and (Δκs) are negative and positive,...
متن کاملThe Effect of Water Surface and Sea Bottom on Sound Propagation in Persian Gulf
Whether exploratory or commercially, acoustic fishery benefits are important in finding a school of fish and other aquatics, but using this procedure and state accurate detailed information for the whole specifications of organisms require sufficient information of sound speed changes, course of ray propagation and their rate of absorption and attenuation . This research has considered the qua...
متن کاملSound Quantity and Quality of Sampo 3065 Combine Harvester
ABSTRACT- Noise is considered as one of the most debilitating conditions in farming operations. In this study, a number of factors affecting the noise generated by Sampo 3065 combine harvesters were evaluated. Factors were engine speed and gear ratio for combines with and without original cabins. A factorial experiment arranged as a completely randomized design with four replicates was used. Re...
متن کاملThe Impact of Trade Openness on Economic Growth in Pakistan; ARDL Bounds Testing Approach to Co-integration
T he main objective of this paper was the investigation of the impact of the trade openness on economic growth in Pakistan. We have been employed both the Johensen and Autoregressive Distributed Lag (ARDL) Co-integration together with ECM Techniques for the period 1975-2016. The empirical estimated results are the sound evidence that there exists a short...
متن کاملThe Ability of Ultrasonic Characterization to Extract the Dose Distribution of MAGIC-f Polymer Gel
Background & Aims: Today, different imaging techniques have been studied in the reading of radiationsensitive polymer gels dosage. Due to limitations of imaging techniques such as magnetic resonance imaging (MRI) and computed tomography (CT), ultrasound techniques are proposed for dose-dependent parameter extraction. In this study, using MAGIC-f (methacrylic and ascorbic acid in gelatin initiat...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 2007