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**What's the Limit of Human Working Capability**

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by
**G.
Ron Chen** (University
of Houston) June 1998

"How can this be possible?"

This is a frequently-asked question that we hear, and that we also

ask when we don't believe something can be done by others if it

cannot be done by ourselves.

When we learned that athlete Carl Lewis, a University of Houston

alumni, won nine gold medals in four consequent Olympic games,

which fall 12 years apart, we asked, "How can this be possible?"

What about mathematics?

Here is a giant master: the Hungarian mathematician Paul Erdös who

died on September 20, 1996, at the age of 83. He published about

1,500 mathematical research papers in his lifetime. You heard me

right: about 1,500 total.

Let's say he started publishing papers at the age of 23. Then, 1500/60

= 25. That's more than two research papers per month throughout 60

years. You counted it right: That's more than two papers per month

over 60 years.

"How can this be possible?"

Perhaps you're rolling your eyes, assuming that he produced a lot of

junk, or simply signed his name after the other authors. Then you got

him totally wrong. Mathematicians know Erdös made very fundamental

contributions to modern mathematics: the Ramsey theory, graph theory,

Diophantine analysis, additive number theory and prime number theory,

to mention just the most important aspects, not to mention that many

papers in these fields were written by himself.

"Well, still, how can this be possible?"

Looking for an answer? Check this out -

"A mathematical genius of the first order, Paul Erdös was totally
obsessed

with his subject - he thought and wrote mathematics for nineteen hours
a

day until the day he died. He traveled constantly, living out of a plastic
bag,

and had no interest in food, sex, companionship, art - all that is usually

indispensable to a human life."

- Oliver Sacks

On backcover of Paul Hoffman's book:

"The Man Who Loved Only Numbers" Hyperion, New York, 1998.

:-)

[**FYI:** **My Erdös
number is** 2:

**Paul Erdös - Charles K. Chui - G. Ron Chen:**

1. Borosh, I., Chui, C. K. and Erdos, P.:
``On changes of signs in infinite series,''

Anal. Math. 4(1), 3-12, 1978.

2. Chui, C. K. and Chen, G.: Kalman
Filtering with Real-Time Applications,

Springer-Verlag (1st ed., 1987; 2nd ed., 1991; 3rd ed., 1999; 4th ed., 2009)

==> Find out your Erdös Number