Department of Energy Argonne National Laboratory Office of Science NEWTON's Homepage NEWTON's Homepage
NEWTON, Ask A Scientist!
NEWTON Home Page NEWTON Teachers Visit Our Archives Ask A Question How To Ask A Question Question of the Week Our Expert Scientists Volunteer at NEWTON! Frequently Asked Questions Referencing NEWTON About NEWTON About Ask A Scientist Education At Argonne Kitty Ket
Name: Lewis C.
Status: educator
Age: 40s
Location: N/A
Country: N/A
Date: Saturday, April 20, 2002 8:17:44 PM

I am curious if it is possible to create a Kitty-Ket.

The first goal is to measure a complete set of quantum observables (commuting observables) to get a complete quantum description of a cat. The second goal is to do this without killing the cat. The desired end result would be a living cat in a pure quantum state -a kitty-ket. Is there some known observable that would be consistent with the classical notion of the "body temperature" of the cat, so that the cat would not be fried by hard radiation (or frozen, for that matter) by the measurement process? I am envisioning measuring the state of each atom and/or molecule, perhaps there is some other method of measuring the cat.


I do not believe such a process is possible. From a quantum point of view, a cat is the total of an enormous number of particles. Since most of an animal is water, divide the mass of a cat by the mass of a water molecule.

Although the energy and momentum of individual molecules is at a quantum level, the motion of a cat indicates the sum of all the energies and all the momenta. When trillions of trillions of particles are added together, the uncertainties of the sums are small enough to be insignificant. To attempt to express a wave function of a cat, you would need trillions of trillions of wave functions as well as interactions between the wave functions. Measurements of "cat qualities" would at best tell you the average qualities.

Dr. Ken Mellendorf
Physics Instructor
Illinois Central College

Click here to return to the Physics Archives

NEWTON is an electronic community for Science, Math, and Computer Science K-12 Educators, sponsored and operated by Argonne National Laboratory's Educational Programs, Andrew Skipor, Ph.D., Head of Educational Programs.

For assistance with NEWTON contact a System Operator (, or at Argonne's Educational Programs

Educational Programs
Building 360
9700 S. Cass Ave.
Argonne, Illinois
60439-4845, USA
Update: June 2012
Weclome To Newton

Argonne National Laboratory