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Uncertainty principle debate



Hello list,
The article by P. Loughlin and L. Cohen entitled "The Uncertainty Principle:
Global, Local, or Both" that appeared in the IEEE Trans. on Signal
Processing (may 2004, pages 1218-1228) may have answers to the following
question.
Best regards,
Ramin

-----Message d'origine-----
De : AUDITORY Research in Auditory Perception
[mailto:AUDITORY(at)LISTS.MCGILL.CA]De la part de herzfeld
Envoye : 30 janvier, 2004 14:37
A : AUDITORY(at)LISTS.MCGILL.CA
Objet : Uncertainty principle debate


Hello List,

The current controversy about the application of the uncertainty
principl;e is to me at least interesting and somewhat perplexing in that
it is still, seems to me, misunderstood.

There are two two methods of defining frequency. One of these is the
inverse of the time difference between two points of equal phase in a
recurring signal. This definition is NOT limited by the uncertainty
principle.[Kneser, H.O. Bermerkungen ueber Definition and Messung der
Frequenz. Arch. Elekt. Uebertr. 1948 2 167-169}

Bekesy in many of his works (based on experimental data) has stated :
Frequency is already determined in 2 cycles of a sinusoidal signal. At a
frequency of 500 Hz the estimate that I have is that the aproximate DL =
1 Hz.  Now two cycles of 500 Hz is 4 mS. The product of delta t and
delta f is 0.004. Very obviously less than 1/2 which (the 1/2) as I
recall was first derived by Gabor [ Gabor, D. Theory of communication.
J. Instn. Elect. Engrs. 1946 93(3) 429-457] See also [Licklider J.C.R.
"Basic correlates of the auditory sto,i;is" in S.S. Stevens (ed)
Handbook of experimental psychology  pp 985-1013 1951 Wiley, New York]
Licklider (one of my teachers) compares this to Heisenberg's uncertainty
principle.

Based on this type of data the determination of frequency by at least
humans and perhaps other vertebrates must be based on time differences.

Fred
--
Fred Herzfeld, MIT'54
78 Glynn Marsh Drive #59
Brunswick, Ga.  31525-0504
USA

Tel: (912) 262-1276
Fax: (912) 262-1276 by request

***********************************
Ramin Pichevar, Ph.D. student
Dept. of Electrical & Computer Eng.
Université de Sherbrooke
2500 boul. de l'université
SHERBROOKE, Québec, CANADA, J1K 2R1
tel: (819)821-8000 ext. 2187
fax: (819)821-7937
http://www-edu.gel.usherbrooke.ca/pichevar/
email: Ramin.Pichevar@usherbrooke.ca
***********************************


"La théorie, c'est quand on sait tout et que rien ne fonctionne. La
pratique,
c'est quand tout fonctionne et que personne ne sait pourquoi. Ici, nous
avons
réunit théorie et pratique : Rien ne fonctionne... et personne ne sait
pourquoi !"
 Albert Einstein