Figure 13. “Zoom in a few times…mysterious
spirals of spirals of spirals appear.”
meshing perfectly with my preoccupations at the
time. For further details, see my earlier tribute [4]
or my home page [5].
Michael Frame
I Believe the Classroom Is an Appropriate
Stage for a Final View of Benoît’s Work
Here I’ll give a sketch of the remarkable breadth
and depth of Benoît’s work, setting most examples
in the world I know best, the classroom. That
students in college, high school, and elementary
school study the concepts Benoît developed filled
him with happiness. In his memoirs [26], Benoît
describes his reaction to student comments after
his lecture, “Uncanny forms of flattery! Each lifted
me to seventh heaven! Truly and deeply, each
marked a very sweet day! Let me put it more
strongly: it is occasions like that that make my
life.” For this reason, I believe the classroom is an
appropriate stage for a final view of Benoît’s work.
In September 2010, a few days after Benoît told
me of his diagnosis, I watched the eighty students
in my fractal geometry course learn in a single class
how to generate the fractals pictured in Figure 12
just by looking at the images and understanding
a few attributes of plane transformations.
Their surprise and satisfaction are what Benoît
gave me, gave the mathematical world. To those
who doubt the value of this approach, I say
compare a standard geometry class lesson on
plane transformations with this day in any fractals
class. The combination of visually complex images
and the ability to decode these images by a few
simple rules explains why fractals are a wonderful
tool for teaching geometry.
A few weeks later in the course, I showed
these pictures again and asked the class to
find their dimensions. Immediately, they answered
log(3)/ log(2) and log(6)/ log(3) for the first two,
and after a moment, log((−1 +
√
3)/2)/ log(1/2)
for the third. That thousands, maybe tens of
thousands, of students know how to compute
and interpret dimensions and that dimension
measures complexity and roughness of objects
mathematical (Julia sets, Kleinian group limit
sets), physical (aggregation clusters, the distribu-
tion of galaxies), biological (pulmonary, nervous,
and circulatory systems), and artistic (Pollock’s
drip paintings, at least according to some) are
due to Benoît. Some knew bits of the picture;
Benoît assembled the whole and got many, many
others working on measuring and interpreting
dimensions.
For the teacher of a fractals class, the best
moment occurs during the day the Mandelbrot
set is introduced. The formula z
n+1
= z
2
n
+ c is
simplicity itself. Describe the iteration process
and the color coding, start the program running
(seconds now for images that burned hours or
days with the personal computers of the mid-
1980s), and wait. (See Figure 1.) Startling baroque
beauty, but from a class jaded by CGI effects,
only a few polite “Oohs” and “Ahhs”. Zoom in a
few times near the boundary; mysterious spirals
of spirals of spirals appear. (See Figure 13). A bit
more emphatic exclamations of surprise, and then,
“You do remember this is produced by iterating
z
n+1
= z
2
n
+ c, don’t you?” Expressions of disbelief
and occasional profanity follow.
Another day or two describing the known ge-
ometry of the Mandelbrot set, the arrangement
of the cyclic components, the infinite cascade of
ever smaller copies of the whole set, and this
complicated object starts to seem familiar. Then
state the hyperbolicity conjecture and point out it
remains a conjecture despite two decades of work
by brilliant mathematicians. Beautiful pictures for
sure; deep, deep mathematics, you bet.
1218
Notices of the AMS
Volume
59, Number 9
Some Key Events in the Life of Benoît B. Mandelbrot
1924
Born in Warsaw, Poland, 20 November
1936
Moved to Paris
1939
Moved to Tulle
1947
Ingenieur diploma, École Polytechnique
1948
M.S. aeronautics, CalTech
1952
Ph.D. mathematics, University of Paris
1953
Postdoc at MIT, then IAS postdoc of von Neumann
1955
Married Aliette Kagan
1958
Moved to the U.S., joined IBM Thomas J. Watson
1963
Publication of “On the variation of certain speculative prices”, [11] and
“The stable Paretian income distribution, when the apparent exponent is near two” [12]
1967
Publication of “How long is the coast of Great Britain?” [13]
1972
Visiting professor of physiology, Albert Einstein College of Medicine
1974
Publication of “Intermittent turbulence in self-similar cascades:
Divergence of high moments and dimension of the carrier” [14]
1975
Publication of Les Objets Fractals: Forme, Hasard et Dimension [15]
1977
Publication of Fractals: Form, Chance, and Dimension [16]
1979
Began studying the Mandelbrot set; formulated the MLC (Mandelbrot
set is locally connected) conjecture
1980
Publication of “Fractal aspects of the iteration of z → λz(1 − z)
for complex λ and z” [17];
formulated the question that the Mandelbrot set is connected
1982
Publication of The Fractal Geometry of Nature [18];
Fellow of the American Academy of Arts and Sciences;
formulated the 4/3 conjecture and that the inside and outside of the
Brownian boundary curve are statistically self-similar; connectivity of the
Mandelbrot set proved by Douady and Hubbard
1984
TED lecture; formulated the n
2
conjecture, proved by
Guckenheimer and McGehee
1985
Barnhard Medal, U.S. National Academy of Sciences;
formulated the conjecture that the boundary of the Mandelbrot
set has dimension 2
1986
Franklin Medal, Franklin Institute; D.Sc., Syracuse University
1987
Foreign associate, U.S. National Academy of Sciences;
Abraham Robinson Adjunct Professor of Mathematical Sciences at Yale;
D.Sc., Boston University
1988
Steinmetz Medal, IEEE; Science for Art Prize, Moet-Hennessy-Louis
Vuitton; CalTech Alumni Distinguished Service Award;
Humboldt Preis, Humboldt-Stifftung;
honorary member, United Mine Workers of America;
D.Sc., SUNY Albany, Universität Bremen
1989
Chevalier, National Legion of Honor, Paris;
Harvey Prize for Science and Technology, Technion;
D.Sc., University of Guelph
1990
Fractals and Music, Guggenheim Museum, with Charles Wuorinen
1991
Nevada Prize
1992
D.Sc., University of Dallas
1993
Wolf Prize in Physics;
D.Sc., Union College, Universitè de Franche-Comtè, Universidad
Nacional de Buenos Aires
October
2012
Notices of the AMS
1219
1994
Honda Prize; J.-C. Yoccoz awarded the Fields Medal, in part for his
work on MLC; Shishikura proved the Mandelbrot set boundary
has dimension 2
1995
D.Sc., Tel Aviv University
1996
Médaille de Vermeil de la Ville de Paris
1997
Publication of Fractals and Scaling in Finance [19]
1998
Foreign member, Norwegian Academy of Sciences and Letters;
C. McMullen awarded the Fields Medal, in part for his work on MLC;
D.Sc., Open University London, University of Business and Commerce Athens
1999
Sterling Professor of Mathematical Sciences at Yale; John Scott Award;
publication of Multifractals and 1/f Noise [20]; publication of
“A multifractal walk down Wall Street” [21]; D.Sc., University of St. Andrews
2000
Lewis Fry Richardson Award, European Geophysical Society
2001
Member, U.S. National Academy of Sciences;
publication of “Scaling in financial prices, I – IV”
2002
Sven Berggren Priset, Swedish Academy of Natural Sciences;
William Proctor Prize, Sigma Xi; Medaglia della Prezidenza della
Republica Italiana; publication of Gaussian Self-Affinity and Fractals [22]
and of Fractals, Graphics, and Mathematics Education [23];
D.Sc., Emory University
2003
Japan Prize for Science and Technology; Best Business Book of the Year
Award, Financial Times Deutschland, for The (Mis)Behavior of Markets [25]
2004
Member, American Philosophical Society; publication of Fractals and
Chaos. The Mandelbrot Set and Beyond [24], and (with R. Hudson
of The (Mis)Behavior of Markets [25]
2005
Sierpinski Prize, Polish Mathematical Society; Casimir Frank Natural
Sciences Award, Polish Institute of Arts and Sciences of America;
Battelle Fellow, Pacific Northwest Labs; D.CE., Politecnio, Torino
2006
Officer, National Legion of Honor, Paris; Einstein Public Lecture, AMS
Annual Meeting; Plenary Lecture, ICM; W. Werner awarded the Fields
Medal for proving (with G. Lawler and O. Schramm) the 4/3 conjecture;
Doctor of Medicine and Surgery, University degli Studi, Bari, Puglia
2010
D.Sc., Johns Hopkins University; TED lecture; S. Smirnov awarded the
Fields Medal for work on percolation theory and SLE related to the
4/3 conjecture.
Died in Cambridge, MA, 14 October
References
[1] M. F. Barnsley and S. G. Demko, Iterated function
systems and the global construction of fractals, Proc.
Roy. Soc. London Ser. A 399 (1985), 243–275.
[2] Michael F. Barnsley, Superfractals: Patterns of
Nature, Cambridge University Press, 2006.
[3] Michael
F.
Barnsley,
Michael
Frame
(eds.),
Glimpses of Benoît B. Mandelbrot (1924–2010), AMS
Notices 59 (2012), 1056–1063.
[4] M. V. Berry, Benefiting from fractals (a tribute to
Benoît Mandelbrot), Proc. Symp. Pure Math., vol. 72,
Amer. Math. Soc., Providence, RI, 2004, pp. 31–33.
[5] http://www.phy.bris.ac.uk/berry mv/
publications.html.
[6] John Brockman, A theory of roughness: a talk with
Benoît Mandelbrot (12.19.04), Edge, http://edge.
org/conversation/a-theory-of-roughness
[7] J. E. Hutchinson, Fractals and self-similarity,
Indiana Univ. Math. J. 30 (1981), 713–747.
[8] J. Kigami, Harmonic calculus on p.c.f. self-similar
sets, Trans. Amer. Math. Soc. 335 (1993), 721–755.
1220
Notices of the AMS
Volume
59, Number 9
[9] M. L. Lapidus, Towards a noncommutative fractal ge-
ometry? Laplacians and volume measures on fractals,
Contemporary Mathematics, vol. 208, 1997, Amer.
Math. Soc., Providence, RI, pp. 211–252.
[10] G. Lawler, O. Schramm, W. Werner, The dimension
of the planar Brownian frontier is 4/3, Math. Res. Lett.
8 (2001), 401–411.
[11] B. Mandelbrot, The variation of certain speculative
prices, J. Business (Chicago) 36 (1963), 394–419.
[12]
, The stable Paretian income distribution when
the apparent exponent is near two, International
Economic Review 4 (1963), 111–115.
[13]
, How long is the coastline of Great Britain?
Science (New Series) 156 (1967), 636–638.
[14]
, Intermittent turbulence in self-similar cas-
cades: Divergences of higher moments and dimen-
sion of the carrier, J. Fluid Mechanics 62 (1974),
331–358.
[15]
, Les Objets
Fractals:
Forme, Hasard
et
Dimension, Flammarion, Paris, 1975.
[16]
, Form, Chance and Dimension, W. H. Freeman,
San Francisco, CA, 1977.
[17]
, Fractal aspects of the iteration z − λz(1 − z)
for complex λ and z, Ann. New York Acad. Sci. 357
(1980), 249–259.
[18]
, The Fractal Geometry of Nature, W. H.
Freeman, San Francisco, CA, 1983.
[19]
, Fractals and Scaling in Finance, Springer-
Verlag, New York, 1997.
[20]
, Multifractals and 1/f Noise, Springer-Verlag,
New York, 1999.
[21]
, A multifractal walk down Wall Street,
Scientific American, Feb. 1999, 70–73.
[22]
, Gaussian Self-Affinity and Fractals, Springer-
Verlag, New York, 2002.
[23]
, Fractals, Graphics, and Mathematics Educa-
tion, MAA, Washington, DC, 2002.
[24]
, Fractals and Chaos: The Mandelbrot Set and
Beyond, Springer-Verlag, New York, 2004.
[25]
, The (Mis)Behavior of Markets, with R. Hudson,
Basic Books, New York, 2003.
[26]
, The Fractalist: Memoir of a Scientific Maverick,
Pantheon, 2012.
[27] D. Mumford, C. Series, D. Wright, Indra’s Pearls,
The Vision of Felix Klein, Oxford University Press,
2002.
[28] James B. Bassingthwaighte, Larry S. Liebovitch,
Bruce J. West
, Fractal Physiology, Oxford University
Press, New York, 1994.
[29] B. J. West, M. Bologna, P. Grigolini, Physics of
Fractal Operators, Springer-Verlag, New York, 2003.
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