# Holy Cow!

Chris sends me arXiv:1005.1381:

A Mathematical Model for the Dynamics and Synchronization of Cows
Authors: Jie Sun, Erik M. Bollt, Mason A. Porter, Marian S. Dawkins
Abstract: We formulate a mathematical model for daily activities of a cow (eating, lying down, and standing) in terms of a piecewise affine dynamical system. We analyze the properties of this bovine dynamical system representing the single animal and develop an exact integrative form as a discrete-time mapping. We then couple multiple cow "oscillators" together to study synchrony and cooperation in cattle herds. We comment on the relevant biology and discuss extensions of our model. With this abstract approach, we not only investigate equations with interesting dynamics but also develop interesting biological predictions. In particular, our model illustrates that it is possible for cows to synchronize \emph{less} when the coupling is increased.

Includes an udder disaster of a last line: "Milking these ideas as much as possible should prove to be very insightful from both theoretical and practical perspectives."

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First, assume a spherical cow ...

By GrayGaffer (not verified) on 13 May 2010 #permalink

>Includes an udder disaster of a last line

What exactly is your beef with that line?

By Angus McPresley (not verified) on 13 May 2010 #permalink

>>Includes an udder disaster of a last line

>What exactly is your beef with that line?

It's kind of cheesy, don't you think?

Dave,

The last line isn't the only one that has a pun. (Check out the second to last line, for example. Also see the acknowledgements and a few other places.) And all of the blogs have given me puns that never even occurred to me, so I already have a list of things to do when the referee reports come.

Cud you please explain how cows oscillate? My fodder always told me never to be afraid to ask questions.

Here are two *useful* facts, relating to the nonlinear problem "Persuade a herd of cows to leave the woods."

(1) You must identify the *boss* cow, and focus on persuading *her* to leave the woods ... all the other cows will follow her lead.

(2) Having identified the boss cow, approach her slowly, softly call "hoeh-bos, hoeh-bos" (this 40,000-year-old Indo-European phrase means "hello cow").

(3) Either gently shoo the boss cow out of the woods, or alternatively, bribe her with some salt.

This is the kind of information, that yah don't really need ... until yah *really* need it! :)