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Re: Heisenberg uncertainty principle for macroscopic objects



If you're wrong about macroscopic objects, Margaret, then so was my QM
professor in grad school at KU. His favorite question on the comprehensive
exam was "How long can an ice pick stay balanced on its point?" His answer,
as I recall, (derived by applying the HUP to the product of ang position and
ang momentum) was about 11 seconds.

poj
Collin County College

----- Original Message -----
From: Margaret Mazzolini <mmazzolini@SWIN.EDU.AU>
To: <PHYS-L@lists.nau.edu>
Sent: Friday, December 17, 1999 2:52 AM
Subject: Heisenberg uncertainty principle for macroscopic objects


It's more years than I care to count since I studied (or taught) quantum
mechanics, so I need a bit of help with a discussion I am having ... I
had thought that the standard popular science type discussion of
Heisenberg's uncertainty principle, where it is claimed that there is a
ridiculously small but non-zero probability that an elephant could
quantum-tunnel through a wall, was falacious because the uncertainty
principle doesn't apply to a macroscopic, incoherent assembly of
particles like an elephant. Am I wrong?
Cheers
Margaret

--
Dr. Margaret Mazzolini
Astronomy Course Coordinator
Swinburne Centre for Astrophysics & Supercomputing
BSEE, Mail Box 31,
Swinburne University of Technology,
PO Box 218 Hawthorn VIC 3122
Australia
email: mmazzolini@swin.edu.au
phone: (+61) 3 9214 8084
fax: (+61) 3 9819 0856

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