Continuous versus discrete time dynamical models of Newton's second fundamental law

التفاصيل البيبلوغرافية
العنوان: Continuous versus discrete time dynamical models of Newton's second fundamental law
المؤلفون: Sergio Invernizzi
المصدر: International Journal of Mathematical Education in Science and Technology. 28:357-365
بيانات النشر: Informa UK Limited, 1997.
سنة النشر: 1997
مصطلحات موضوعية: Mathematics (miscellaneous), Discrete time and continuous time, Applied Mathematics, Ordinary differential equation, Mathematical analysis, Zero (complex analysis), Motion (geometry), Initial value problem, Tangent, Function (mathematics), Arc length, Education, Mathematics
الوصف: There exist vertical plane C 1 ‐smooth curves such that the classical Newton mechanics based on ordinary differential equations cannot uniquely determine the future motion of a particle sliding down under the effect of gravity. As a simple example, we explicitly construct a C 1 concave curve 7 such that the tangent component of the gravity as a function of the arc length parameter is F(s)= |s|1/3 sgn (s). Actually, the Cauchy problem ? = F(s), s(0) = 0, ?(0) = 0 has an infinite number of solutions (Peano phenomenon). Physically, this analysis is paradoxical, since it allows that the particle rests motionless at the top of 7 for an arbitrary time interval, and then suddenly moves away. Here we propose a possible solution of the paradox showing that these ‘unwelcome’ solutions are obtained by a limiting process from special orbits of the corresponding discrete time model (which obviously respects the wished determinism in the future) as the fundamental time period ?tgoes to zero.
تدمد: 1464-5211
0020-739X
URL الوصول: https://explore.openaire.eu/search/publication?articleId=doi_________::e43634ae18daf02847bf70e2230d552a
https://doi.org/10.1080/0020739970280305
رقم الأكسشن: edsair.doi...........e43634ae18daf02847bf70e2230d552a
قاعدة البيانات: OpenAIRE