aczel, amir d - fermat's last theorem_uc
TRANSCRIPT
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PRAISE FOR AMIR D. ACZEL'S
FERMAT'S LAST THEOREM
"This is a captivating volume. . . . The brilliant backdoor method
used by Mr. Wiles as he reached his solution, along with the debt he
owed to many other contemporary mathematicians, is graspable in
Mr. Aczel's lucid prose. !ually important is the sense o awe that Mr.
Aczel imparts or the hidden, mystical harmonies o numbers, and
or that sense o awe alone, his slender volume is well worth the
e#ort."
The New York Times
"$or more than three centuries, $ermat's %ast Theorem was the most
amous unsolved problem in mathematics, here's the story o how it
was solved. . . . An e&cellent short history o mathematics, viewed
through the lens o one o its great problems and achievements."
Kirkus Reviews
"This e&citing recreation o a landmark discovery reveals the great
e&tent to which modern mathematics is a collaborative enterprise. . .
. While avoiding technical details, Aczel maps the strange, beautiul
byways o modern mathematical thought in ways the layperson can
grasp."
Publishers Weekly
"(rie)y chronicles the history o the amous problem o the title,
which was recently solved by a mathematician named Andrew Wiles
ater he had devoted seven years to the task. . . . Aczel does a
superb *ob o creating in the nonmathematical reader the illusion o
comprehension."The New Yorker
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$3MAT'4 %A4T T563MUnlocking the Secret ojan ncient
!athematical Problem
By Amir D. Aczel
D e l t a
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A Delta Book
P!li"#e$ !y Dell
P!li"#i%& a
$ii"io% o(
Ba%tam Do!le$ay Dell P!li"#i%& )ro*+ I%c.
,-/ Broa$0ay
1e0 2ork+ 1e0 2ork ,//34
Co*yrit 5 ,664 !y Amir D Aczel
All rit" re"ere$. 1o *art o( t#i" !ook may !e re*ro$ce$ or tra%"mitte$ i%
a%y (orm or !y a%y mea%"+ electro%ic or mec#a%ical+ i%cl$i%& *#otoco*yi%&+
recor$i%&+ or !y a%y i%(ormatio% "tora&e a%$ retrieal "y"tem+ 0it#ot t#e
0ritte% *ermi""io% o( t#e P!li"#er+ e7ce*t 0#ere *ermitte$ !y la0. For
i%(ormatio% a$$re""8 For 9all" Eit 9i%$o0"+ 1e0 2ork+ 12+ ,//,,.
T#e tra$emark Delta: i" re&i"tere$ i% t#e ;.S. Pate%t a%$ Tra$emark O
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Pre"ace
7n 8une ,663+ my old riend Tom 4chulte was visiting me in (oston
rom 9aliornia. We were sitting at a sunny sidewalk cae on
:ewbury 4treet, tall, icy drinks in ront o us. Tom had *ust gotten
divorced, and he was ruminative. 5e hal turned toward me. "(y the
way," he said, "$ermat's %ast Theorem has *ust been proved." This
must be a new *oke, 7 thought, as Tom's attention was back on thesidewalk. Twenty years earlier, Tom and 7 were roommates, both o
us undergraduate students in mathematics at the ;niversity o
9aliornia at (erkeley. $ermat's %ast Theorem was something we
oten talked about. We also discussed unctions, and sets, and
number
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in mathematics, unaware o my own background in math, o#ered
me his help when we met at the 7nternational 5ouse where we both
lived. "7'm in pure mathematics," he said. "7 you ever have a math
problem you can't solve, eel ree to ask me." 5e was about to
leave, when 7 said ";rn, yes. There is something you can help me
with . . . " 5e turned back, "Why, sure, let me see what it is." 7
pulled open a napkinwe were at the dining room. 7 slowly wrote on
it?
#n$ yn% znhas no whole number solution when n is greater
than @.
"7've been trying to prove this one since last night," 7 said,handing him the napkin. 7 could see the blood draining rom his
ace. "$ermat's %ast Theorem," he grunted. "es," 7 said, "ou're in
pure math. 9ould you help me>" 7 never saw that person rom up
close again.
"7 am serious," Tom said,
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the accolades belong to others as much? Ben 3ibet, (arry Mazur,
Coro 4himura, utaka Taniyama, Cerhard $rey and others. This book
tells the entire story, including what happened behind the scenes
and out o the view o the media's cameras and )oodlights. 7t is
also a story o deception, intrigue, and betrayal.
7:
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&Perha's ( coul) best )escribe my e#'erience o" )oing
mathematics in terms oj entering a )ark mansion* You go into the
+rst room an) it,s )ark- com'letely )ark* You stumble aroun)-
bum'ing into the "urniture* .ra)ually- you learn where each 'iece
o" "urniture is* n) +nally- a"ter si# months or so- you +n) the light
switch an) tum it on* Su))enly- it,s all illuminate) an) you can see
e#actly where you were* Then you enter the ne#t )ark room * * * &
This is how Pro"essor n)rew Wiles )escribe) bis seven/year
0uest "or the mathematicians, 1oly .rail*
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8ust beore dawn on 8une @ 3+ , 66 3+ +roessor 8ohn 9onway
approached the darkened mathematics building on the +rinceton
;niversity campus. 5e unlocked the ront door and !uickly walked
up to his o=ce. $or weeks preceding his colleague Andrew Wiles'
departure or ngland, persistent but unspeci
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o thinning light hair. (orn in 9ambridge, his return was a very
special kind o homecomingit was the realization o a childhood
dream. 7n pursuit o this dream, Andrew Wiles had spent the last
seven years o his lie a virtual prisoner in his own attic. (ut he
hoped that soon the sacri
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comments that help them improve the papers beore they are
published. (ut Wiles didn't hand out preprints and didn't discuss his
work. The title o Wiles' talks was "Modular $orms, lliptic 9urves,and Calois 3epresentations," but the name gave no hint where the
lectures would lead, and even e&perts in his
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4himura0Taniyama 9on*ecture. Then suddenly he added one
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an "amateur" since he had a day *ob as a *urist, the leading histo0
rian o mathematics . T. (ell, writing in the early part o the
twentieth century, aptly called $ermat the "+rince o Amateurs."
(ell believed $ermat to have achieved more important mathe0
matical results than most "proessional" mathematicians o his day.
(ell argued that $ermat was the most proli
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Pierre $e Fermat'" La"t T#eorem a" re*ro$ce$ i% a% e$itio% o( Dio*#a%t"'
rithmetica *!li"#e$ !y Fermat'" "o% Samel. T#e ori&i%al co*y o( Dio*#a%t"
0it# Fermat'" #a%$0ritte% %ote #a" %eer !ee% (o%$.
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mat, who was 4econd 9onsul in the town o (eaumont0de0%omagne,
and o 9laire de %ong, the daughter o a amily o parliamentary
*udges. The young $ermat was born in August, , 4/ , baptized
August @/ in (eaumont0de0%omagne2, and was raised by his
parents to be a magistrate. 5e went to school in Toulouse, and was
installed in the same city as 9ommissioner o 3e!uests at the age
o thirty. 5e married %ouise %ong, his mother's cousin, that same
year, ,43,. +ierre and %ouise had three sons and two daughters.
6ne o their sons, 9lement 4amuel, became his ather's scienti
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diversion rom his hard work, and since he had to limit his social
lie, mathematics probably o#ered a much0needed break. And the
ideas o calculus were ar rom $ermat's only achievement. $ermat
brought us number theory. An important element in number theory
is the concept o a prime number.
Prime Numbers
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The numbers two and three are prime numbers. The number our is
not prime because it is the product o two and two? @ & @ .
The number + nine is not 3 & 36+ and
ten is not @ & -,/. (ut eleven again is a prime number since
there are no integers other than eleven itsel and one2, which can
be multiplied together to give us , , . And we can continue this
way? ,@ is not prime, ,3 is, , is not, ,- is not, ,4 is not, ,? is
prime, and so on. There is no apparent structure here, such as
every ourth number is not a prime, or even any more complicated
pattern. The concept has mysti
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All o $ermat's other theorems were either proved or disproved by
the early , >/ /" . This seemingly simple statement remained
unsettled, and thereore was given the name "$ermat's %ast The0
orem." Was it indeed true> ven in our own century, computers
were stymied in attempts to veriy that the theorem was true.
9omputers could veriy the theorem or very large numbers, but
they couldn't help or all numbers. The theorem could be tried on
billions o numbers, and there still would be in
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close riend o Andrew Wiles, watched him agonize every day over
the proo he had told the entire world he possessed only two
months earlier in 9ambridge. "7t's as i Andrew was trying to lay an
over0sized carpet on the )oor o a room," 4arnak e&plained. "5e'd
pull it out, and the carpet would
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roots o this theorem are grounded in the everyday lie o the
people o Mesopotamia o @/// (.9. .
The era rom @ // / (.9. to 4 // (.9. in the Mesopotamian
valley is considered the (abylonian ra. This time saw remarkable
cultural developments, including writing, the use o the wheel, and
metal works. A system o canals was used or irrigating large tracts
o land between the two rivers. As civilization )ourished in the
ertile valley o (abylon, the ancient people who inhabited these
planes learned to trade and to build prosperous cities such as
(abylon and %lr where Abraham was born2. ven earlier, by the
end o the ourth millennium (.9., a primitive orm o writing had
already developed in both the Mesopotamian and the :ile river
valleys. 7n Mesopotamia, clay was abundant and wedge0shaped
marks were impressed with a stylus on sot clay tablets. These
tablets were then baked in ovens or let to harden in the sun. This
orm o writing is called cuneiorm, a word derived rom the %atin
word cuneus- meaning wedge. The cuneiorm constitutes the
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Wealth (s a S;uare) 0uantity
A sophisticated number system was developed using base si&ty and
(abylonian engineers and builders were able to compute the
!uantities re!uired in their everyday proessional lives. 4!uares o
numbers appear naturally in lie, although it doesn't seem so at
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F E R M A T ' S L A S T T H E O R E M
&Plim'ton 7
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The (abylonians' approach was not to develop a general theory
or solving such problems, but rather to provide tables listing triples
o numbers andapparentlyto teach pupils how to read and use
these tables.
n ncient Society o" Number/Worshi''ers Sworn to Secrecy
+ythagoras was born on the Creek island o 4amos around 1L/ (.C.
5e travelled e&tensively throughout the ancient world and visited
(abylon, gypt, and possibly even 7ndia. 7n his travels, especially in
(abylon, +ythagoras came in contact with mathematicians and likely
became aware o their studies o numbers now named ater him
the +ythagorean triples,
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which (abylonian scientists and mathematicians had known about
(or over ,- // years. +ythagoras came in contact with the
builders o magni
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A M I R D . A C Z E L
&Number (s
3verything&
7n the barren, stark surroundings o the tip o 7taly, +ythagoras
ounded a secret society dedicated to the study o numbers. The
society, whose members became known collectively as the
+ythagoreans, is believed to have developed a substantial body o
mathematical knowledgeall in complete secrecy. The
+ythagoreans are believed to have ollowed a philosophy sum0
marized by their motto that "number is everything." They wor0
shipped numbers and believed them to have magical properties. An
ob*ect o interest to them was a "perect" number. 6ne o the
de + since
the numbers that can divide @> without remainder2 are ,+ @+ +
?+ and , + and we note that also? , G @ G G ? G ,
@>.
The +ythagoreans ollowed an ascetic liestyle, and were strict
vegetarians. (ut they did not eat beans, thinking they resembled
testicles. Their preoccupations with number were very much in the
spirit o a religion, and their strict vegetarianism originated in
religious belies. While no documents survive dating to the time o
+ythagoras, there is a large body o later literature about the
master and his ollowers, and +ythagoras himsel is considered one
o the greatest mathematicians o
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anti!uity. To him is attributed the discovery o the +ythagorean
Theorem concerning the s!uares o the sides o a right triangle,
which has strong bearing on +ythagorean triples and, ultimately, on
$ermat's %ast Theorem two thousand years later.
The S;uare oj the 1y'otenuse (s 3;ual to the
Sum oj the S;uares oj the =ther Two Si)es* * *
The theorem itsel originated in (abylon, since the (abylonians
clearly understood "+ythagorean" triples. The +ythagoreans,
however, are credited with setting the problem in geometric
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terms, and thus generalizing them away rom strictly the natural
numbers positive integers without zero2. The +ythagorean
Theorem says that the s!uare o the hypotenuse o a right0triangle
is e!ual to the sum o the s!uares o the two remaining sides o the
triangle, as shown above.
When the hypotenuse is an integer such as -+ whose s!uare is
@- + the general +ythagorean solution in terms o the sum o two
s!uares will be the integers our whose s!uare is si&teen2 and
three whose s!uare is nine2. 4o the +ythagorean Theorem, when
applied to integers whole numbers such as ,+ @+ 3+ . . .
gives us the +ythagorean triples which were known a millennium
earlier in (abylon.
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7ncidentally, the +ythagoreans also knew that s!uared numbers
are sums o se!uences o odd numbers. $or e&le, , G
3 + = 6 , G 3 G - + = ,4 , G 3 G - G ?+ and so on. This
property they represented by a visual array o numbers in a s!uare
pattern. When the odd number o dots along two ad*acent sides is
added to the previous s!uare, a new s!uare is ormed?
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Whole Numbers- 8ractions- an) What 3lse>
(ut the +ythagoreans knew a lot more than whole numbers and
ractions numbers such as ,@+ ,3+ ->+ ,?,?46+ etc.2,
which were known in anti!uity both in (abylon and in gypt. The
+ythagoreans are the ones who discovered the irrational numbers
that is, numbers that cannot be written as ractions but have to be
written as unending, non0repeating decimals. 6ne such e&le is
the number pi 3 .,,-6@4- . . . 2, the ratio o the
circumerence o a circle to its diameter. The number pi is
unending,0 it would take orever to write it down completely since it
has in
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number was not an integer, nor even a raction, a ratio o two
integers. This was a number with an unending decimal represen0
tation which did not repeat itsel. As is the case with pi, to write
down the e&act number that is the s!uare root o two
,.,@,3-4@ . . . 2 would take orever, since there are in-?,@>-?,@>-?,@>-?,@>-? . . . + etc., which
one could describe without having to actually write down every
digit2. Any number with a repeating decimal representation here,
the se!uence >-?,@ repeats itsel over and over again in the
decimal part o this number2, is a rational number, that is, a
number that can also be written in the orm alb- that is, the ratio o
two integers. 7n this e&le, the two integers are ,3 and ?. The
ratio ,3? is e!ual to ,.>-?,@>-?,@>-?,@>-?,@ . .
. , the pattern >-?,@ repeating itsel orever.
The discovery o the irrationality o the s!uare root o two
surprised and shocked these diligent number admirers. They swore
never to tell anyone outside their society. (ut word got out. And
legend has it that +ythagoras himsel killed by drowning the
member who divulged to the world the secret o the e&istence o
the strange, irrational numbers.
The numbers on the number line are o two distinct kinds?
rational and irrational. %ooked at together, they
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around every irrational number there are in @3 =, >6 , taunted and ridiculed 9antor or his
theories about how many rational and irrational numbers0 there are.
Bronecker is known or his statement, "Cod made the integers, and all
the rest is the work o man," meaning that he did not even believe that
the irrational numbers, such as the s!uare root o two, e&istedE This,
over two millennia ater the +ythagoreans.2 5is antagonism is blamed
or having prevented 9antor rom obtaining a proessorship at the
prestigious ;niversity o (erlin, and ultimately or 9antor's re!uent
nervous breakdowns and his ending up at an asylum or the mentally
in
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F E R M A T ' S L A S T T H E O R E M The
Pythagorean ?egacy
An important aspect o +ythagorean lie, with its dietary rules and
number worship and secret meetings and rituals, was the pursuit o
philosophical and mathematical studies as a moral basis. 7t is
believed that +ythagoras himsel coined the words'hiloso'hy@ love
o wisdom,0 and mathematics/- that which is learned. +ythagoras
transormed the science o mathematics into a liberal orm o
education.
+ythagoras died around 1// (.9. and let no written records o
his work. 5is center at 9rotona was destroyed when a rival political
group, the 4ybaritics, surprised the members and murdered most o
them. The rest dispersed about the Creek world around the
Mediterranean, carrying with them their philosophy and number
mysticism. Among those who learned the philosophy o
mathematics rom these reugees was +hilolaos o Tarentum, who
studied at the new center the +ythagoreans established in that city.
+hilolaos is the
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were mystical. A diagonal point divides a diagonal into two une!ual
parts. The ratio o the entire diagonal to the larger segment is
e&actly the same as the ratio o the larger segment to the smaller
one. This same ratio e&ists in all smaller and smaller diagonals. This
ratio is called the Colden 4ection. 7t is an irrational number e!ual to
,.4,> . . . 7 you divide , by this number, you get e&actly the
decimal part without the , . That is, you get /.4,>. . . . As we
will see later, the Colden 4ection appears in natural phenomena as
well as proportions that the human eye perceives as beautiul. 7t
appears as the limit o the ratio o the amous $ibonacci numbers
we will soon encounter.
ou can .. . and / .4 ,> .. . inter0
changeably, once you have done the repetitive set o operations
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enough times. This is the Colden 4ection. 7t is e!ual to the s!uare
root o
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+
whos
e
sum
is
,/.
And
,/+
in
turn,
is
the
base
o
our
num
ber
syste
m.
The
+yth
agor
eans
repre
sent
ed
the
num
ber
,/
as a
trian
gle,
whic
h
they
calle
d
tetra
ktys/
*
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The +ythagoreans considered the tetraktys holy and even swore
oaths by it. 7ncidentally, according to Aristotle as well as 6vid and
other classical writers, the number ten was chosen as the base or
the number system because people have ten
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If the river carried away any portion of a man' !ot" the #in$ ent peron to
e%amine and determine &y mearement the e%act e%tent of the !o( From
thi practice" I thin#" $eometry firt came to &e #nown in E$ypt" whence it
paed into )reece(
Ceometry is the study o shapes and
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theorem is a rigorous *usti
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em limit arguments are not di#erent rom udo&us' "e&haustion"
method.
(ut the most brilliant mathematician o anti!uity wasundoubtedly Archimedes @>?=@,@ (.9.2, who lived in the city o
4yracuse on the island o 4icily. Archimedes was the son o the
astronomer +heidias, and was related to 5ieron 77, the king o
4yracuse. %ike udo&us, Archimedes developed methods or
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his mathematician riend to
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Archimedes' avorite theorem had to do with the sphere inside
the cylinder and he wrote the theorem in a book called The !etho)*
As with most ancient te&ts, it was assumed lost. 7n ,6/4 + the
Fanish scholar 8. %. 5eiberg heard that in 9onstantinople there was
a aded parchment manuscript with writings o a mathematical
nature. 5e traveled to 9onstantinople and ound the manuscript,
consisting o ,>- leaves o parchment. 4cienti
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7t is not certain when Fiophantus lived. We can date his period
based only on two interesting acts. $irst, he !uotes in his writings
5ypsicles, who we know lived around ,-/ (.9. And second,
Fiophantus himsel is !uoted by Theon o Ale&andria. Theon's timeis dated well by the solar eclipse which occurred on 8une ,4+ A.F.
34. 4o Fiophantus certainly lived beore A.F. 34 but ater ,-/
(.9. 4cholars, somewhat arbitrarily, place him at about A.F. @-/.
Fiophantus wrote the rithmetica- which developed algebraic
concepts and gave rise to a certain type o e!uation. These are the
Fiophantine e!uations, used in mathematics today. 5e wrote
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called the 9rusades, the Arabs ruled a )ourishing empire rom the
Middle ast to the 7berian +eninsula. Among their great
achievements in medicine, astronomy, and the arts, the Arabs
developed algebra. 7n A.F. 43@+ the prophet Mohammed
established an 7slamic state centered at Mecca, which remains thereligious center o 7slam. 4hortly aterwards, his orces attacked the
(yzantine mpire, an o#ensive which continued ater Mohammed's
death in Medina that same year. Within a ew years, Famascus,
8erusalem, and much o Mesopotamia ell to the orces o 7slam, and
by A.F. 4 , so did Ale&andriathe mathematical center o the
world. (y A.F. Q1/, these wars as well as the ones among the
Moslems themselves subsided and the Arabs o Morocco and the
west were reconciled with the eastern Arabs centered in (aghdad.
(aghdad became a center o mathematics. The Arabs absorbed
mathematical ideas as well as discoveries in astronomy and other
sciences rom the inhabitants o the areas they overcame. 4cholarsrom 7ran, 4yria, and Ale&andria were called to (aghdad. Furing the
reign o the caliph Al Mamun in the early L//s, the rabian Nights
was written and many Creek works, including uclid's 3lements-
were translated into Arabic. The caliph established a 5ouse o
Wisdom in (aghdad, and one o its members was Mohammed 7bn
Musa Al0Bhowarizmi. %ike uclid, Al0Bhowarizmi was to become
world0renowned. (orrowing 5indu ideas and symbols or numerals,
as well as Mesopotamian concepts and uclid's geometrical
thought, Al0Bhowarizmi wrote books on arithmetic and algebra. The
word "algorithm" is derived rom Al0Bhowarizmi. And the word
"algebra" is derived rom the
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Bhowarizmi's most well0known book?l 4abr Wa,l !ucjabalah* 7t was
rom this book that urope was later to learn the branch o
mathematics called algebra. While algebraic ideas are in the root o
Fiophantus'ritbmetica- thel 4abr is more closely related to the
algebra o today. The book is concerned with straightorward
solutions o e!uations o
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ety o the time brought him into contact with Arab mathematical
ideas, as well as Creek and 3oman culture. When the emperor
$rederick 77 came to +isa, $ibonacci was introduced to the emperor's
court and became a member o the imperial entourage.
7n addition to ?iber 0ua)ratorum- $ibonacci is known or another
book he wrote at that time, ?iber baci* problem about
+ythagorean triangles in $ibonacci's book also appears in a
(yzantine manuscript o the eleventh century now in the 6ld +alace
library in 7stanbul. 7t could be a coincidence,0 on the other hand,
$ibonacci might have seen that same book in 9onstantinople during
his travels.
$ibonacci is best known or the se!uence o numbers named
ater him, the $ibonacci :umbers. These numbers originate in the
ollowing problem in the ?iber baci/*
How many pair of ra&&it wi!! &e prodced in a year" &e$innin$ with a
in$!e pair" if in every month each pair &ear a new pair which &ecome
prodctive from the econd month on-
The $ibonacci se!uence, which is derived rom this problem, is
one where each term ater the + ,3+ @,+ 3+ --+ >6+ ,+ . . .
This se!uence which is taken to continue beyond the ,@
months o the problem2 has une&pectedly signi+ >,3+ ,3@,+ @,3+ 3--+ -->6+ >6,+ etc.
:ote that these numbers get closer and closer to "r- 0 l@.
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This is the Colden 4ection. 7t can also be obtained using a calculator
by repeating the operation lOl G lOl G , . . . . as described earlier.
3ecall that the reciprocal lO&2 o the Colden 4ection gives the same
number, less , . The $ibonacci se!uence appears everywhere in
nature. %eaves on a branch grow at distances rom one another that
correspond to the $ibonacci se!uence. The $ibonacci numbers occur
in )owers. 7n most )owers, the number o petals is one o? 3+ -+ >+
, 3+ @ , + 3 + - -+ or > 6 . %ilies have three petals, buttercups
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The $ibonacci numbersappear in sun)owerstoo. The little )oretsthat become seeds inthe head o thesun)ower are arrangedin two sets o spirals?one winding in aclockwise direction andthe other counter0clockwise. The numbero spirals in theclockwise orientation isoten thirty0our and thecounter0clockwise
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on a branch.
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The rectangle has appealing proportions. The Colden 4ection
appears not only in nature but also in art as the classic ideal o
beauty. There is something divine about the se!uence, and in act
the $ibonacci 4ociety, which is active today, is headed by a priest
and centered at 4t. Mary's 9ollege in 9aliornia. The 4ociety is
dedicated to the pursuit o e&les o the Colden 4ection and
$ibonacci :umbers in nature, art, and architecture, with the belie
that the ratio is a git o Cod to the world. As the ideal o beauty,
the Colden 4ection appears in such places as the Athenian
+arthenon. The ratio o the height o the +arthenon to its length is
the Colden 4ection.
The Parthenon, Athens, Greece.
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The great +yramid at Ciza, built many hundreds o years beore
the Creek +arthenon, has ratio o height o a ace to hal the side o
the base also in the Colden 4ection. The gyptian 3hind +apyrus
reers to a "sacred ratio." Ancient statues as well as renaissancepaintings display the proportions e!ual to the Colden 4ection, the
Fivine 3atio.
The Colden 4ection has been searched or as the ideal o beauty
beyond )owers or architecture. 7n a letter to the $ibonacci 4ociety
some years ago, a member described how someone looking to .
The 2ossistsMathematics entered Medieval urope through $ibonacci's works
and rom 4pain, then part o the Arab world, with the work o Al
Bhowarizmi. The main idea o algebra in those days was to solve
e!uations or an unknown !uantity. Today, we call the unknown
!uantity "&," and try to solve an e!uation or whatever value "&"
may have. An e&le o the simplest e!uation is? & 0 - / .
5ere, we use simple math operations to
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When these ideas were imported to urope, the Arabic shai was
translated into %atin. 7n %atin, "thing" is res, and in 7talian it is cosa*
4ince the
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Tartaglia revealed his method, on the condition that 9ardano keep it
a secret rom the rest o the world. When 9ardano later learned the
same methods rom another cossist, 4cippi0one del $erro ,-4=
,-@4+ he immediately assumed that Tartaglia got his system
rom this person, and elt ree to reveal the secret. 9ardano then
published the methodology or solving cubic e!uations in his ,--
book rs !agna* Tartaglia elt betrayed and became urious with
9ardano. 7n his last years, he spent much o his time viliying his
ormer riend, and he succeeded in diminishing 9ardano's
reputation.
The cossists were considered mathematicians o a lower level
than the ancient Creeks. Their preoccupation with applied problems
in pursuit o
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obtained a copy o the Creekrithmetica o Fiophantus, translated
it and published it as 9io'hanti le#an)rini rithmeticorum ?ibri Se#
in +aris in ,4@,. 7t was a copy o this book that ound its way to
$ermat.
$ermat's theorem says that there are no possible +ythagorean
triples or anything beyond s!uares. There are no triples o numbers,
two adding up to the third, where the three numbers are perect
cubes o integers, or ourth0powers o integers,
S;uares- 2ubes- an) 1igher 9imensions
A theorem is a statement with a proo. $ermat claimed to have had a
"marvelous proo," but without seeing and validating the proo no
one could call his statement a theorem. A statement may be very
deep, very meaningul and important, but without the proo that it is
indeed true, it must be called a con*ecture, or sometimes a
hypothesis. 6nce a con*ecture is proven it then can be called a
theorem- or a lemma i it is a preliminary proven statement which
then leads to a more proound theorem. +roven results that ollow a
theorem are called corollaries. And $ermat had a number o such
statements. 6ne such statement was that the number @ @ A J , G, was
always a prime number. This con*ecture was not only not proven,
hence not a theorem, it was actually proven to be wrong*This was
done by the great 4wiss mathematician %eonhard uler ,?/?=
,?>3 in the ollowing century. 4o there was no reason to believe
that the "last theorem" was true. 7t could be true, or it could be
alse. To prove that $ermat's %ast Theorem was alse all some0
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one would have to do is to
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correct or the e&ponents 3+ + - + 4 + and ?. 7t would be a long
way to in
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hard's parents to allow him to pursue mathematics, since he would
become a great mathematician. %eonhard, however, continued with
the theology in addition to mathematics, and religious eelings and
customs would be a part o his entire lie.
Mathematicial and scienti
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this way he could *oin his two riends who had such e&cellent
positions doing nothing but their own research in 3ussia.
uler ound mathematics in whatever he studied, medicine
included. 4tudying ear physiology led him to a mathematical
analysis o the propagation o waves. At any rate, soon an invitation
came rom 4t. +etersburg, and in ,?@? he *oined his two riends.
5owever, on the death o +eter's wie 9atherine, there was chaos at
the academy since she had been the great supporter o research. 7n
the conusion, %eonhard uler slipped out o the medical section
and somehow got his name listed with the mathematical section,
where he would rightully belong. $or si& years he kept his head low
to prevent the detection o his move, and he avoided all social
interactions lest the deception be discovered. All through this
period he worked continuously, producing volumes o top0rated
mathematical work. 7n , ?3 3 he was promoted to the leading
mathematical position at the academy. Apparently uler was a
person who could work anywhere, and as his amily was growing,
he would oten do his mathematics while holding a baby in one
arm.
When Anna 7vanova, +eter the Creat's niece, became empress o
3ussia, a period o terror began and uler again hid himsel in his
work or ten years. Furing this period he was working on a di=cult
problem in astronomy or which a prize was o#ered in +aris. A
number o mathematicians re!uested several months' leave rom
the academy to work on the problem. uler solved it in three days.
(ut the concentrated e&ertion took its toll and he became blind in
his right eye.
uler moved to Cermany to be at the royal academy there, but
did not get along with the Cermans, who en*oyed long
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philosophical discussions not to his taste. 9atherine the Creat o
3ussia invited uler back to the 4t. +etersburg academy and he was
more than happy to come back. At that time, the philosopher Fenis
Fiderot, an atheist, was visiting 9atherine's court. The empress
asked uler to argue with Fiderot about the e&istence o Cod.Fiderot, in the meantime, was told that the amous mathematician
had a proo o Cod's e&istence. uler approached Fiderot and said
gravely? "4ir, a $ bin % #- hence Cod e&ists,0 replyE" Fiderot, who
knew nothing about mathematics, gave up and immediately
returned to $rance.
Furing his second stay in 3ussia, uler went blind in his second
eye. 5e continued, however, to do mathematics with the help o his
sons, who did the writing or him. (lindness increased his mental
ability to do complicated calculations in his head. uler continued to
do mathematics or seventeen years and died while playing with his
grandson in ,?>3 . Much o the mathematical notation we usetoday is due to uler. This includes the use o the letter i or the
basic imaginary number, the s!uare root o = , . uler loved one
mathematical ormula, which he considered the most beautiul and
put it above the gates o the Academy. The ormula is?
eR G - N /
This ormula has , and /+ basic to our number system,0 it has the
three mathematical operations? addition, multiplication, and
e&ponentiation,0 and it has the two natural numbers pi and e,0 and
it has i" the basis or the imaginary numbers. 7t is also visually
appealing.
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The Seven :ri)ges oj Konigsberg
uler was such an incredible visionary in mathematics that his
pioneering work on imaginary numbers and what today is called
comple& analysis2, was not his only innovation. 5e did pioneering
work in a
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uler asked whether or not it was possible to cross all seven
bridges without passing twice on any bridge. 7t is impossible. 6ther
problems, which were studied in modern times and were posed
because o interest in the seven bridges problem, are the various
map0coloring problems. A cartographer draws a map o the world.
7n this map, each country is colored di#erently, to distinguish it
rom its immediate neighbors. Any two countries or states that are
separated completely rom each other may be colored in the same
e&act color. The !uestion is, what is the minimum number o colors
re!uired so that no two states that touch each other are in the
same color> 6 course, this is a general problem, not bounded by
how the map o the world looks today. The !uestion is really, given
all possible con Civen boundaries between
states in the ormer ugoslavia or in the Middle ast, with very
unusual lines between political entities, this general problem
becomes relevant in applications.
Mathematically, this is a topological problem. 7n 6ctober ,>-@+
$rancis Cuthrie was coloring a map o ngland. 5e wondered what
would be the minimum number o colors to be used or the
counties. 7t occurred to him that the number should be our. 7n
, >? 6 a proo was given that the number was indeed our, but
later the proo was ound to be alse. Almost a century later, in
,6?4 + two mathematicians, 5aken and Appel, proved what had
become known as the $our 9olor Map problem. To this day,
however, their proo is considered controversial since it made use o
computer work, rather than pure mathematical logic.
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.auss- The .reat .erman .enius
An alleged error in uler's proo or n N 3 that is, or cubes2 was
corrected by 9arl $riedrich Causs ,???=,>--. While most o the
renowned mathematicians o this time were $rench, Causs,
undoubtedly the greatest mathematician o the timeand arguably
o all timeswas unmistakably Cerman. 7n act, he never let
Cermany, even or a visit. Causs was the grandson o a very poor
peasant, and the son o a laborer in (runswick. 5is ather was harsh
with him, but his mother protected and encouraged her son. oung
9arl was also taken care o by his uncle $riedrich, the brother o
Causs' mother Forothea. This uncle was wealthier than 9arl's par0
ents and made a reputation or himsel in the
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-+/-/+ written on it. Apparently, Causs 66,//
,// 66 6> 6?..... 3 @ , /
5e noted that the sum o each column was ,//+ so there was
nothing long to add up. 4ince there were ,/, columns, the sum o
all the numbers was ,/, & ,//,/+,//. :ow, either o the two
rows had the sum he neededall the numbers rom , to ,//.
4ince he needed only one o the two rows, the answer was hal o
,/+,//+ or -+/-/. Pery simple, he thought. The teacher,
however, learned a lesson and never again assigned the youngCauss a math problem as punishment.
When he was 6>.
Causs' results in number theory, which were shared with the
mathematicians o his day by regular correspondence, were o great
importance in all attempts by mathematicians to prove
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$ermat's %ast Theorem. Many o these results were contained in a
book on number theory which Causs published in %atin in ,>/,+
when he was @. The book, 9ist"uisitiones rithmeticae, was
translated into $rench and published in +aris in ,>/? and received
much attention. 7t was recognized as the work o genius. Causs
dedicated it to his patron, the Fuke o (runswick.
Causs was a distinguished scholar o classical languages as well.
6n entering college he was already a master o %atin, and his
interest in philology precipitated a crisis in his career. 4hould he
ollow the study o languages or o mathematics> The turning point
was March 3/+ ,?64. $rom his diary, we know that on that day
the young Causs decided de Causs' riend 5. W. M. 6lbers
wrote him a letter rom (remen on March ?+ ,>,4+ in which he
told Causs that the +aris Academy o#ered a big prize or anyone
who would present a proo or a disproo o $ermat's %ast Theorem.
Causs surely could use the money, his riend suggested. At that
time, as he did throughout his mathematical career, Causs received
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(ut Causs would not be tempted. +ossibly he knew how
deceptive $ermat's %ast Theorem really was. The great genius in
number theory may have been the only mathematician in urope torealize *ust how di=cult it would be to prove. Two weeks later,
Causs wrote to 6lbers his opinion o $ermat's %ast Theorem? "7 am
very much obliged or your news concerning the +aris prize. (ut 7
coness that $ermat's Theorem as an isolated proposition has very
little interest or me, because , could easily lay down a multitudeo such propositions, which one could neither prove nor dispose o."
7ronically, Causs made great contributions to the branch o
mathematics known as comple& analysisan area incorporating the
imaginary numbers worked on by uler. 7maginary numbers would
have a decisive role in twentieth0century understanding o the con0
te&t o $ermat's %ast Theorem.
(maginary Numbers
The comple& number
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o = , + denoted by i. They were put on their own number line,
perpendicular to the real number line. Together, these two a&es
give us the comple& plane. The comple& plane is shown below. 7t
has many surprising properties, such as rotation being
multiplication by i*
Mlti*licatio% !y i rotate" co%terclock0i"e.
The comple& plane is the smallest , , + decades ahead o his time, Causs was
studying the behavior o unctions on the comple& plane. 5e
discovered some amazing properties o these unctions, known as
analytic unctions. Causs ound that analytic unctions had special
smoothness, and they allowed
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or particularly neat calculations. Analytic unctions preserved
angles between lines and arcs on the planean aspect that wouldbecome signi=,>4. When the theory reemerged without Causs' name
attached to it years later, other mathematicians were given credit
or work on the same analytic unctions Causs understood so well.
So'hie .ermain
6ne day Causs received a letter rom a certain "Monsieur %eblanc."%eblanc was ascinated with Causs' book, 9iscjuisitiones
rithmeticae- and sent Causs some new results in arithmetic theory.
Through the ensuing correspondence on mathematical matters,
Causs gained much respect or Mr. %eblanc and his work. This
appreciation did not diminish when Causs discovered that neither
was his correspondent's real name %eblanc, nor was the writer o
the letters a "Mr." The mathematician writing so elo!uently to
Causs was one o very ew women active in the proession at that
time, 4ophie Cermain ,??4=,>3,. 7n act, upon discovering the
deception, Causs wrote her?
Bt #o0 to $e"cri!e to yo my a$miratio% a%$
a"to%i"#me%t at "eei%& my e"teeme$
corre"*o%$e%t Mr. Le!la%c metamor*#o"e #im"el(
i%to t#i" ill"trio" *er"o%a&e 0#o &ie" "c# a
!rillia%t e7am*le o( 0#at , 0ol$ %$ $i< clt to
!eliee...
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A letter rom Causs to 4ophie Cermain, written rom (runswick on
Causs' birthday, as stated in $rench at the end o his letter?"(ronsvic ce 3/ avril ,>/? *our de ma naissance."2
4ophie Cermain assumed a man's name to avoid the pre*udice
against women scientists prevalent in those days and to gain
Causs' serious attention. 4he was one o the most important
mathematicians to attempt a proo o $ermat's %ast Theorem, and
to make considerable headway on the problem. 4ophie Cermain's
Theorem, which gained her much recognition, states that i a
solution o $ermat's e!uation with K- e&isted, then all three
numbers had to be divisible by -. OThe theorem separated $ermat's
%ast Theorem into two cases? 9ase 7 or numbers not divisible by -+
and 9ase 77 or numbers that are. The theorem was generalized toother powers, and 4ophie Cermain gave a general theorem which
allowed or a proo o $ermat's %ast Theorem or all prime numbers,
n- less than ,// in 9ase 7. This was an important result, which
reduced the possible cases where $ermat's %ast Theorem might ail
or primes less than ,// to only 9ase 77.4ophie Cermain had to
drop the disguise she was using when Causs asked his riend
"%eblanc" or a avor. 7n ,>/?+ :apoleon was occupying Cermany.
The $rench were imposing war
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one to intercede on his behal with the $rench Ceneral +er0nety in
5anover.5e wrote his riend, Monsieur %eblanc, to ask i %eblanc might
contact the $rench Ceneral on Causs' behal. When 4ophie Cermain
gladly complied, it became clear who she was. (ut Causs was
thrilled, as seen rom his letter, and their correspondence continued
and developed urther on many mathematical topics. ;nortunately,
the two never met. 4ophie Cermain died in +aris in ,>3,+ beore
the ;niversity o Cottingen could award her the honorary doctorate
which Causs had recommended she receive.
4ophie Cermain had many other achievements to her credit in
addition to her contributions to the solution o $ermat's %ast
Theorem. 4he was active in the mathematical theories o acousticsand elasticity, and other areas in applied and pure mathematics. 7n
number theory, she also proved theorems on which prime numbers
can lead to solvable e!uations.
The :laDing 2omet o" i > a
Causs did much important work in astronomy, determining the
orbits o planets. 6n August @@+ ,>,,+ he
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retreated rom 3ussia. Causs was amused. 5e was not unhappy to
see the mperor deeated ater $rench orces had e&torted such
high amounts rom him and his countrymen.
The 9isci'le
The :orwegian mathematician :iels 5enrik Abel visited +aris in
6ctober o ,>@4. There, he tried to meet other mathematicians
+aris was at that time a mecca or mathematics. 6ne o the people
who impressed Abel the most was +eter Custav %e*eune Firichlet
,>/-=,>-6+ a +russian who was also visiting +aris and
gravitated toward the young :orwegian, at
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the book o the seven seals? The gited Firichlet is known as the
person who broke the seven seals. Firichlet did more than anyone
else to e&plain and interpret the book o his great master to the rest
o the world.
(esides ampliying and e&plaining the 9is0uisitiones- as well as
proving $ermat's %ast Theorem or the power
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ter's position. When Causs died in ,>--+ Firichlet let his
prestigious *ob in (erlin to accept the honor o replacing Causs at
Cottingen.
Na'oleon,s !athematicians
The mperor o the $rench loved mathematicians, even i he wasn't
one himsel. Two who were especially close to him were
CaspardMonge ,?4=,>,>+ and 8oseph $ourier ,?4>=,>3/.
7n ,?6>+ :apoleon took the two mathematicians with him to gypt,
to help him "civilize" that ancient country.
$ourier was born in Au&erre, $rance, on March @,+ ,?4>+ but at
the age o eight he was orphaned and was helped by the local
(ishop to enter the military school. ven at the age o twelve,
$ourier showed great promise and was writing sermons or church
dignitaries in +aris, which they passed o# as their own. The $rench
3evolution o ,?>6 saved the young $ourier rom lie as a priest.
7nstead he became a proessor o mathematics, and an enthusiastic
supporter o the revolution. When the revolution gave way to the
Terror, $ourier was repulsed by its brutality. 5e used his elo!uence,
developed over years o writing sermons or others, to preach
against the e&cesses. $ourier also used his great public speaking
skills in teaching mathematics at the best schools in +aris.
$ourier was interested in engineering, applied mathematics, and
physics. At the cole +olytechni!ue, he did serious research in these
areas, and many o his papers were presented to the Academy. 5is
reputation brought him to the attention o :apoleon, and in ,?6>
the mperor asked $ourier to accompany him, aboard his )agship,
along with the $rench )eet o
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dred ships headed or gypt. $ourier was to be part o the %egion o
9ulture. The %egion's charge was to "endow the people o gypt
with all the bene
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AMIR D. ACZEL
Perio)ic 8unctions
The clearest e&le o a periodic unction is your watch. Minute by
minute, the large hand moves around a circle, and ater si&ty
minutes it comes back to the e&act same place where it started.
Then it continues and in e&actly si&ty minutes it again returns to the
same spot. 6 course the little hand will have changed positions as
the hours go by.2 The minutes hand on a watch is a periodic
unction. 7ts period is e&actly si&ty minutes. 7n a sense, the space o
all minutes o eternitythe set o in
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$e%e$ a" t#e "i%e (%ctio%. T#i" i" t#e eleme%tary
tri&o%ometric (%ctio% tat at "c#ool. T#e co"i%e
(%ctio% i" t#e #orizo%tal mea"re o( t#e arm. Bot#
"i%e a%$ co"i%e are (%ctio%" o( t#e a%&le t#e arm
make" 0it# a #orizo%tal li%e t#ro t#e ce%ter o(
t#e 0#eel. T#i" i" "#o0% !elo0.
As the train moves orward, the vertical height o the arm traces
a wave0pattern as seen above. This pattern is periodic. 7ts period is
K/ degrees. $irst the arm's height is zero, then it goes up in a
wave0like ashion until it reaches one, then it decreases, then it
goes to zero again, then to negative values until one, then its
negative magnitude decreases to zero. And then the cycles starts
all over again.
What $ourier discovered was that most unctions can be
estimated to any degree o accuracy by the sum o many the0
oretically in
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lea$ to t#e $i"coery o( atomor*#ic (%ctio%" a%$
mo$lar (orm"0#ic# al"o #a$ a crcial im*act o%
Fermat'" La"t T#eorem t#ro t#e early t0e%tiet#
ce%try 0ork o( a%ot#er Fre%c# mat#ematicia%+ He%ri
Poi%care.
?ame Proo"
At t#e Marc# ,+ ,>? meeti%& o( t#e Pari" Aca$emy+
t#e mat#ematicia% )a!riel Lame ,?6-=,>?/
a%%o%ce$ ery e7cite$ly t#at #e #a$ o!tai%e$ a
&e%eral *roo( o( Fermat'" La"t T#eorem. ;%til t#e%+o%ly "*ecic *o0er"+ n- 0ere attacke$+ a%$ a *roo(
#a$ !ee% &ie% o( t#e t#eorem i% t#e ca"e" % 3+ +
-+ ?. Lame "&&e"te$ t#at #e #a$ a &e%eral a**roac#
to t#e *ro!lem+ 0#ic# 0ol$ 0ork (or a%y *o0er n*
Lame'" met#o$ 0a" to (actor t#e le(t "i$e o( Fermat'"
eatio%+ 7-/%G y%+ i%to li%ear (actor" "i%& com*le7 %m!er".Lame t#e% 0e%t o% to "tate mo$e"tly t#at t#e &lory"#ol$ %ot all &o to #im+ "i%ce t#e met#o$ #e"&&e"te$ 0a" i%tro$ce$ to #im !y o"e*# Lioille,>/6=,>>@. Bt Lioille took t#e *o$im a(terLame a%$ !r"#e$ a"i$e a%y *rai"e. Lame #a$ %ot*roe$ Fermat'" La"t T#eorem+ #e ietly "tate$+!eca"e t#e (actorizatio% #e "&&e"te$ 0a" %ot%ie t#at i"+ t#ere 0ere ma%y 0ay" to carry ott#e (actorizatio%+ "o t#ere 0a" %o "oltio%. It 0a" a&alla%t attem*t+ o%e o( ma%y+ !t it $i$ %ot !ear(rit. Ho0eer+ t#e i$ea o( (actorizatio%+ t#at i"+!reaki%& $o0% t#e eatio% to a *ro$ct o( (actor"+0a" to !e trie$ a&ai%.
()eal Numbers
T#e *er"o% to a&ai% try (actorizatio% 0a" Er%"t
E$ar$ m=mer ,>,/=,>63t#e ma% 0#o &ot
clo"er t#a% a%yo%e el"e i%
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#i" time to a &e%eral "oltio% o( Fermat'" *ro!lem.
mmer+ i% (act+ i%e%te$ a% e%tire t#eory i%
mat#ematic"+ t#e t#eory o( i$eal %m!er"+ i%
attem*ti%& to *roe Fermat'" La"t T#eorem.Bummer'" mot#er+ a 0i$o0 0#e% #er "o% 0a" o%ly
t#ree+ 0orke$ #ar$ to a""re #er !oy a &oo$
e$catio%. At t#e a&e o( eitee% #e e%tere$ t#e
;%ier"ity o( Halle+ i% )erma%y+ to "t$y t#eolo&y
a%$ *re*are #im"el( (or li(e i% t#e c#rc#. A%
i%"it(l *ro(e""or o( mat#ematic" 0it# e%t#"ia"m
(or al&e!ra a%$ %m!er t#eory &ot t#e yo%&
mmer i%tere"te$ i% t#e"e area"+ a%$ #e "oo%
a!a%$o%e$ t#eolo&y (or mat#ematic". I% #i" t#ir$
year a" a "t$e%t+ t#e yo%& mmer "ole$ a $i(=
clt *ro!lem i% mat#ematic" (or 0#ic# a *rize #a$!ee% oNere$. Follo0i%& t#i" "cce""+ #e 0a" a0ar$e$
a $octorate i% mat#ematic" at t#e a&e o( t0e%ty=o%e.
Bt mmer 0a" %a!le to %$ a %ier"ity
*o"itio% a%$ t#ere(ore #a$ to take a teac#i%& o! at
#i" ol$ &ym%a"im #i "c#ool. He remai%e$ a
"c#oolteac#er (or a%ot#er te% year". T#root t#i"
*erio$+ mmer $i$ mc# re"earc#+ 0#ic# #e
*!li"#e$ a%$ 0rote i% letter" to "eeral lea$i%&
mat#ematicia%" o( #i" time. Hi" (rie%$" realize$ #o0
"a$ it 0a" to #ae "c# a &i(te$ mat#ematicia% "*e%$
#i" li(e teac#i%& #i "c#ool mat#. 9it# t#e #el* o("ome emi%e%t mat#ematicia%"+ mmer 0a" &ie%
t#e *o"itio% o( *ro(e""or at t#e ;%ier"ity o( Bre"la.
A year later+ i% ,>--+ )a"" $ie$. Diric#let #a$ take%
)a""' *lace at )otti%&e%+ leai%& !e#i%$ #i" ol$ o!
at t#e *re"ti&io" ;%ier"ity o( Berli%. mmer 0a"
c#o"e% to re*lace Diric#let i% Berli%. He remai%e$ i%
t#at *o"itio% %til #i" retireme%t.
mmer 0orke$ o% a 0i$e ra%&e o( *ro!lem" i%
mat#emat=
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ic"+ ra%&i%& (rom ery a!"tract to ery a**lie$ee%
a**licatio%" o( mat#ematic" i% 0ar(are. Bt #e ma$e
#i" %ame (or #i" e7te%"ie 0ork o% Fermat'" La"t
T#eorem. T#e Fre%c# mat#ematicia% A&"ti%=Loi"
Cac#y ,?>6=,>-?+ t#ot o% a %m!er o(
occa"io%" t#at #e #a$ (o%$ a &e%eral "oltio% to t#e
Fermat *ro!lem. Bt t#e re"tle""+ carele"" Cac#y
realize$ i% eery attem*t t#at t#e *ro!lem 0a" mc#
!i&&er t#a% #e #a$ a""me$. T#e el$" o( %m!er"
#e 0a" 0orki%& 0it# al0ay" (aile$ to #ae t#e
*ro*erty #e reire$. Cac#y le(t t#e *ro!lem a%$
0e%t to 0ork o% ot#er t#i%&".
mmer !ecame o!"e""e$ 0it# Fermat'" La"t
T#eorem+ a%$ #i" attem*t" at a "oltio% le$ #im
$o0% t#e "ame (tile track take% !y Cac#y. Bt
i%"tea$ o( &ii%& * #o*e 0#e% #e reco&%ize$ t#at
t#e %m!er el$" i%ole$ (aile$ to #ae "ome *ro*=
erty+ #e i%"tea$ invente) %e0 %m!er" t#at 0ol$ #ae
t#e *ro*erty #e %ee$e$. T#e"e %m!er" #e calle$
i$eal %m!er". mmer t#" $eelo*e$ a% e%tirely
%e0 t#eory (rom "cratc#+ 0#ic# #e "e$ i% #i"
attem*t" to *roe Fermat'" La"t T#eorem. At o%e
*oi%t+ mmer t#ot #e %ally #a$ a &e%eral
*roo(+ !t t#i" %(ort%ately (ell "#ort o( 0#at 0a"
%ee$e$.
1o%et#ele""+ mmer $i$ ac#iee treme%$o"
&ai%" i% #i" attack o% t#e Fermat *ro!lem. Hi" 0ork
0it# i$eal %m!er" e%a!le$ #im to *roe Fermat'"
La"t T#eorem (or a ery e7te%"ie cla"" o( *rime
%m!er" a" t#e e7*o%e%t n* T#"+ #e 0a" a!le to
*roe t#at Fermat'" La"t T#eorem 0a" tre (or a%
i%%ite %m!er o( e7*o%e%t"+ %amely t#o"e t#at are
$ii"i!le !y re&lar *rime". T#e irre&lar *rime
%m!er" el$e$ #im. T#e o%ly irre&lar *rime" le""
t#a% ,// are 3?+ -6+ a%$ 4?. mmer t#e% 0orke$
"e*arately o% t#e *ro!lem o( t#e"e
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irre&lar *rime %m!er" a%$ 0a" ee%tally a!le to
*roe Fermat'" t#eorem (or t#e"e %m!er". By t#e
,>-/"+ "i%& m=mer'" i%cre$i!le !reakt#ro"+
Fermat'" La"t T#eorem 0a" k%o0% to !e tre (or all
e7*o%e%t" le"" t#a% n % ,//+ a" 0ell a" i%%itely
ma%y mlti*le" o( *rime %m!er" i% t#i" ra%&e. T#i"
0a" ite a% ac#ieeme%t+ ee% i( it 0a" %ot a
&e%eral *roo( a%$ "till le(t ot i%%itely ma%y
%m!er" (or 0#ic# it 0a" %ot k%o0% 0#et#er t#e
t#eorem #el$ tre.
I% ,>,4+ t#e Fre%c# Aca$emy o( Scie%ce" oNere$ a
*rize to a%yo%e 0#o 0ol$ *roe Fermat'" La"t
T#eorem. I% ,>-/ t#e Aca$emy a&ai% oNere$ a &ol$
me$al a%$ 3+/// (ra%c" to t#e mat#ematicia% 0#o
0ol$ *roe Fermat'" La"t T#eorem. I% ,>-4+ t#e
Aca$emy $eci$e$ to 0it#$ra0 t#e a0ar$+ "i%ce it
$i$%'t "eem like a "oltio% to Fermat'" *ro!lem 0a"
immi%e%t. I%"tea$+ t#e Aca$emy $eci$e$ to &ie t#e
a0ar$ to Er%"t E$ar$ mmer+ (or #i" !eati(l
re"earc#e" o% t#e com*le7 %m!er" com*o"e$ o(
root" o( %ity a%$ i%te&er". T#" mmer 0a"
a0ar$e$ a *rize (or 0#ic# #e %eer ee% a**lie$.
mmer co%ti%e$ #i" tirele"" eNort" o% Fermat'"
La"t T#eorem+ "to**i%& #i" re"earc# o%ly i% ,>?.
mmer al"o $i$ *io%eeri%& 0ork o% t#e &eometry o(
(or=$ime%"io%al "*ace. Some o( #i" re"lt" are
"e(l i% t#e el$ o( mo$er% *#y"ic" k%o0% a"
a%tm mec#a%ic". mmer $ie$ o( t#e Q i% #i"
eitie"+ i% ,>63.
mmer'" "cce"" 0it# i$eal %m!er" i" ee% more
#ily *rai"e$ !y mat#ematicia%" t#a% t#e actal
a$a%ce" #e ma$e i% t#e "oltio% o( Fermat'"
*ro!lem "i%& t#e"e %m!er". T#e (act t#at t#i"
%ota!le t#eory 0a" i%"*ire$ !y attem*t" to "ole Fer=
mat'" La"t T#eorem "#o0" #o0 %e0 t#eorie" ca% !e
$eelo*e$
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!y attem*t" to "ole *articlar *ro!lem". I% (act+
mmer'" t#eory o( i$eal %m!er" le$ to 0#at are
%o0 k%o0% a" i$eal"+ 0#ic# #ae #a$ a% im*act o%t#e 0ork o( 9ile" a%$ ot#er mat#ematicia%" o%
Fermat'" t#eorem i% t#e t0e%tiet# ce%try.
nother PriDe
I% ,6/>+ t#e 9ol("ke#l Prize o( o%e #%$re$ t#o"a%$
mark" 0a" oNere$ i% )erma%y (or a%yo%e 0#o 0ol$
come * 0it# a &e%eral *roo( o( Fermat'" La"t
T#eorem. I% t#e r"t year o( t#e *rize+ 4@,
"oltio%" 0ere "!mitte$. All o( t#em 0ere (o%$ to
!e (al"e. I% t#e (ollo0i%& year"+ t#o"a%$" more
"oltio%" 0ere "!mitte$+ 0it# t#e "ame eNect. I%t#e ,6@/"+ )erma% #y*eri%Qatio% re$ce$ t#e real
ale o( t#e ,//+/// mark" to %ot#i%&. Bt (al"e
*roo(" o( Fermat'" La"t T#eorem co%ti%e$ to *or
i%.
.eometry Without 3ucli)
1e0 $eelo*me%t" "tarte$ taki%& *lace i%
mat#ematic" i% t#e %i%etee%t# ce%try. a%o" Bolyai
,>/@=,>4/ a%$ 1icola" Ia%oitc# Lo!ac#e"ky
,?63=,>-4+ a H%&aria% a%$ a R""ia% re"*ectiely+
c#a%&e$ t#e (ace o( &eometry. By $oi%& a0ay 0it#Ecli$'" a7iom t#at t0o *arallel li%e" %eer meet+
t#e"e t0o 0ere a!le i%$e*e%$e%tly to (ormlate a
&eometrical %ier"e 0#ic# mai%tai%e$ ma%y o(
Ecli$'" *ro*ertie" !t allo0e$ t0o *arallel li%e" to
meet at a *oi%t at i%%ity. A $iNere%t &eometry ca%
!e "ee%+ (or e7am*le+ o% a "*#ere "c# a" t#e &lo!e.
Locally+ t0o lo%&it$e li%e" are *arallel. Bt i%
reality+ a" t#ey are (ollo0e$ to t#e 1ort# Pole+ t#e
t0o li%e" meet t#ere. 1e0 &eome
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trie" "ole ma%y *ro!lem" a%$ e7*lai% "itatio%"
0#ic#+ %til t#at time+ "eeme$ my"terio" a%$
0it#ot a "oltio%.
:eauty an) Trage)y
A!"tract al&e!ra+ a el$ $erie$ (rom t#e (amiliar
al&e!ra tat i% "c#ool a" a "y"tem (or "oli%&
eatio%"+ 0a" $eelo*e$ i% t#e %i%etee%t# ce%try.
I% t#i" area+ t#e !eati(l t#eory o( )aloi" "ta%$" ot.
Eari"te )aloi" 0a" !or% i% ,>,, i% t#e "mall
illa&e o( Bor&=la=Rei%e+ ot"i$e Pari". Hi" (at#er
0a" t#e mayor o( t#e to0% a%$ a "ta%c# re*!lica%.
2o%& Eari"te &re0 * o% t#e i$eal" o( $emocracy
a%$ (ree$om. ;%(ort%ately+ mo"t o( Fra%ce 0a" att#at time #ea$i%& i% t#e o**o"ite $irectio%. T#e
Fre%c# Reoltio% #a$ come a%$ &o%e+ a%$ "o #a$
1a*oleo%. Bt t#e $ream" o( (ree$om+ eality+ a%$
(rater%ity #a$ %ot yet !ee% ac#iee$. A%$ t#e
royali"t" 0ere e%oyi%& a come!ack i% Fra%ce+ 0it# a
Bor!o% o%ce a&ai% cro0%e$ i%& o( t#e Fre%c#%o0
to rle to&et#er 0it# t#e *eo*le'" re*re"e%tatie".
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Eari"te'" li(e 0a" "tee*e$ i% t#e lo(ty i$eal" o( t#e
reoltio%. He 0a" a &oo$ i$eolo&e+ a%$ #e &ae
"ome moi%& "*eec#e" to t#e re*!lica%". A" a
mat#ematicia%+ o% t#e ot#er #a%$+ #e 0a" a &e%i"
o( %*arallele$ a!ility. A" a tee%a&er+ )aloi"
a!"or!e$ t#e e%tire t#eorie" o( al&e!ra a%$
eatio%" k%o0% to accom*li"#e$ mat#ematicia%" o(
#i" $ay+ a%$0#ile "till a "c#ool!oy$eelo*e$ #i"
o0% com*lete "y"tem+ k%o0% to$ay a" )aloi" T#eory.
;%(ort%ately+ #e 0a" %ot to e%oy a%y reco&%itio% i%
#i" tra&ically "#ort li(e. )aloi" "taye$ * %it" at #i"
!oar$i%& "c#ool+ 0#ile eeryo%e el"e "le*t+ a%$ 0rote
$o0% #i" t#eory. He "e%t it to t#e #ea$ o( t#e Fre%c#
Aca$emy o( Scie%cet#e mat#ematicia% Cac#y
#o*i%& t#at Cac#y 0ol$ #el* #im *!li"# t#e
t#eory. Bt Cac#y 0a" %ot o%ly ery !"y+ #e 0a"
al"o arro&a%t a%$ carele"". A%$ )aloi"' !rillia%t
ma%"cri*t e%$e$ * i% a tra"# ca%+ %rea$.
)aloi" trie$ a&ai%+ 0it# t#e "ame re"lt. I% t#e
mea%time+ #e (aile$ to *a"" t#e e%try e7am" to t#e
L7ole Polytec#%ie+ 0#ere mo"t o( t#e cele!rate$
mat#ematicia%" o( Fra%ce &ot t#eir trai%i%&. )aloi"
#a$ a #a!it o( al0ay" 0orki%& t#i%&" ot i% #i" #ea$.
He %eer took %ote" or 0rote t#i%&" $o0% %til #e
#a$ actal re"lt". T#i" met#o$ co%ce%trate$ o% i)eas
rat#er t#a% $etail. 2o%& Eari"te #a$ little *atie%ce
(or+ or i%tere"t i%+ t#e $etail". It 0a" t#e &reat i$ea+
t#e !eaty o( t#e lar&er t#eory+ t#at i%tere"te$ #im.
Co%"ee%tly+ )aloi" 0a" %ot at #i" !e"t 0#e% taki%&
a% e7ami%atio% i% (ro%t o( a !lack!oar$. A%$ t#i" i"
0#at ca"e$ #im to (ail t0ice i% #i" attem*t" to &ai%
e%tra%ce to t#e "c#ool o( #i" $ream". T0ice i% (ro%t
o( t#e !lack!oar$ #e $i$ %ot *er(orm 0ell 0riti%&
t#i%&" $o0%+ a%$ #e &ot irritate$ 0#e% a"ke$ (or
$etail" #e "t $i$%'t co%"i$er
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im*orta%t. It 0a" a tra&e$y t#at a%i%cre$i!lyi%telli&e%t yo%& *er"o% 0ol$ !e
e"tio%e$ !y mc# le"" a!le e7ami%er" 0#o col$
%ot %$er"ta%$ #i" $ee* i$ea" a%$ took #i"
relcta%ce to &ie triial $etail" (or i&%ora%ce. 9#e%
#e realize$ #e 0a" &oi%& to (ail t#e "eco%$ a%$ la"t
*ermi""i!le attem*t+ a%$ t#at t#e &ate" o( t#e "c#ool
0ol$ !e clo"e$ to #im (oreer+ )aloi" t#re0 t#e
!lack!oar$ era"er i% t#e (ace o( #i" e7ami%er.
)aloi" #a$ to make $o 0it# a "eco%$=!e"t c#oice+
t#e Ecole 1ormale. Bt ee% t#ere #e $i$ %ot (are
0ell. )aloi"' (at#er+ t#e mayor o( Bor&=la=Rei%e+ 0a"t#e tar&et o( clerical i%tri&e" i% t#e to0%. A%
%"cr*lo" *rie"t circlate$ *or%o&ra*#ic er"e"+
"i&%i%& t#em 0it# t#e mayor'" %ame. Mo%t#" o( "c#
*er"ectio% ca"e$ )aloi"' (at#er to lo"e #i"
co%$e%ce a%$ #e !ecame co%i%ce$ t#at t#e 0orl$
0a" ot to &et #im. Slo0ly lo"i%& toc# 0it# reality+
#e 0e%t to Pari". T#ere+ i% a% a*artme%t %ot (ar (rom
0#ere #i" "o% 0a" "t$yi%&+ t#e (at#er kille$ #im"el(.
T#e yo%& )aloi" %eer recoere$ (rom t#i" tra&e$y.
O!"e""e$ 0it# t#e lo"t ca"e o( t#e ,>3/ reoltio%+
a%$ (r"trate$ 0it# t#e "c#ool $irector+ 0#om #eco%"i$ere$ a% a*olo&i"t (or t#e royali"t" a%$ cleric"+
)aloi" 0rote a "cat#i%& letter criticizi%& t#e $irector.
He 0a" i%"*ire$ to $o "o a(ter t#ree $ay" o( rioti%& i%
t#e "treet"+ 0#e% "t$e%t" all oer Pari" 0ere
reolti%& a&ai%"t t#e re&ime. )aloi" a%$ #i"
cla""mate" 0ere ke*t locke$ i% t#eir "c#ool+ %a!le
to "cale t#e tall (e%ce. T#e a%&ry )aloi" "e%t #i"
!li"teri%& letter criticizi%& t#e "c#ool $irector to t#e
.aDette )es +coles* A" a re"lt+ #e 0a" e7*elle$ (rom t#e
"c#ool. Bt )aloi" 0a" %$a%te$#e 0rote a "eco%$
letter to t#e .aDette- a%$ a$$re""e$ t#e "t$e%t" att#e "c#ool to "*eak * (or #o%or a%$ co%"cie%ce. He
&ot %o re"*o%"e.
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Ot o( "c#ool+ )aloi" "tarte$ oNeri%& *riatele""o%" i% mat#ematic". He 0a%te$ to teac# #i" o0%
mat#ematical t#eorie"+ ot"i$e t#e Fre%c# "c#ool"+
0#e% #e 0a" all o( %i%etee% year" ol$. Bt )aloi"
col$ %ot %$ "t$e%t" to teac##i" t#eorie" 0ere
too a$a%ce$ #e 0a" (ar a#ea$ o( #i" time.
Faci%& a% %certai% (tre a%$ $oome$ %ot to !e
a!le to *r"e a $ece%t e$catio%+ i% $e"*eratio%
)aloi" oi%e$ t#e artillery !ra%c# o( t#e Fre%c#
1atio%al )ar$. Amo%& t#e 1atio%al )ar$+ #ea$e$
i% it" *a"t !y La(ayette+ t#ere 0ere ma%y li!eral
eleme%t" clo"e to yo%& )aloi"' *olitical *#ilo"o*#y.9#ile i% t#e )ar$+ )aloi" ma$e o%e la"t attem*t to
*!li"# #i" mat#ematical 0ork. He 0rote a *a*er o%
t#e &e%eral "oltio% o( eatio%"to$ay reco&%ize$
a" t#e !eati(l )aloi" T#eorya%$ "e%t it to Simeo%=
De%i" Poi""o% ,?>,=,>/ at t#e Fre%c# Aca$emy o(
Scie%ce". Poi""o% rea$ t#e *a*er !t $etermi%e$
t#at it 0a" i%com*re#e%"i!le. O%ce a&ai%+ t#e
%i%etee%=year=ol$ 0a" "o (ar a#ea$ o( a%y o( t#e
ol$er Fre%c# mat#ematicia%" o( #i" $ay t#at #i"
ele&a%t %e0 t#eorie" 0e%t 0ay oer t#eir #ea$". At
t#at mome%t+ )aloi" $eci$e$ to a!a%$o%mat#ematic" a%$ to !ecome a (ll=time reoltio%ary.
He "ai$ t#at i( a !o$y 0a" %ee$e$ to &et t#e *eo*le
i%ole$ 0it# t#e reoltio%+ #e 0ol$ $o%ate #i".
O% May 6+ ,>3,+ t0o #%$re$ yo%& re*!lica%"
#el$ a !a%et i% 0#ic# t#ey *rote"te$ a&ai%"t t#e
royal or$er $i"!a%$i%& t#e artillery o( t#e 1atio%al
)ar$. Toa"t" 0ere oNere$ to t#e Fre%c# Reoltio%
a%$ it" #eroe"+ a" 0ell a" to t#e %e0 reoltio% o(
,>3/. )aloi" "too$ * a%$ *ro*o"e$ a toa"t. He "ai$
To Loi" P#ili**e+ t#e Dke o( Orlea%"+ 0#o 0a"
%o0 i%& o( t#e Fre%c#. 9#ile "ayi%& t#i"+ #ol$i%& *#i"
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&la""+ )aloi" 0a" al"o #ol$i%& * a% o*e% *ocket=
k%i(e i% #i" ot#er #a%$. T#i" 0a" i%ter*rete$ a" a
t#reat o% t#e li(e o( t#e i%&+ a%$ ca"e$ a riot. T#e
%e7t $ay )aloi" 0a" arre"te$.
I% #i" trial (or t#reate%i%& t#e li(e o( t#e i%&+
)aloi"' attor%ey claime$ t#at )aloi" #a$ actally "ai$+
0#ile #ol$i%& #i" k%i(e+ To Loi" P#ili**e+ i( #e
!ecome" a traitor. Some o( )aloi"' artillery (rie%$"
0#o 0ere *re"e%t te"tie$ to t#i"+ a%$ t#e ry (o%$
#im %ot &ilty. )aloi" retriee$ #i" k%i(e (rom t#e
ei$e%ce ta!le+ clo"e$ it a%$ *t it i% #i" *ocket+ a%$
le(t t#e cortroom a (ree ma%. Bt #e 0a" %ot (ree
(or ery lo%&. A mo%t# later #e 0a" arre"te$ a" a
$a%&ero" re*!lica%+ a%$ ke*t i% ail 0it#ot a
c#ar&e 0#ile t#e at#oritie" looke$ (or a c#ar&e
a&ai%"t #im t#at 0ol$ "tick. T#ey %ally (o%$ o%e
0eari%& t#e %i(orm o( t#e $i"!a%$e$ artillery. )aloi"
0a" trie$ (or t#i"8#ar&e a%$ "e%te%ce$ to "i7 mo%t#"
i% ail. T#e royali"t" 0erc*lea"e$ to %ally *t a0ay a
t0e%ty=year=ol$ t#ey co%"i$ere$ to !e a $a%&ero"
e%emy o( t#e re&ime. )aloi" 0a" *arole$ a(ter "ome
time a%$ 0a" moe$ to a #al(0ay (acility. 9#at
#a**e%e$ %e7t i" o*e% to e"tio%. 9#ile o% *arole+
)aloi" met a yo%& 0oma% a%$ (ell i% loe. Some
!eliee #e 0a" "et * !y #i" royali"t e%emie" 0#o
0a%te$ to *t a% e%$ to #i" reoltio%ary actiitie"
o%ce a%$ (or all. At a%y rate+ t#e 0oma% 0it# 0#om
#e &ot i%ole$ 0a" o( e"tio%a!le irte E&une
cocjuette )e has e,tage&F* A" "oo% a" t#e t0o !ecame
loer"+ a royali"t came to "ae #er #o%or a%$
c#alle%&e$ )aloi" to a $el. T#e yo%&
mat#ematicia% 0a" le(t %o 0ay ot o( t#e me"". He
trie$ eeryt#i%& #e col$ to talk t#e ma% ot o( t#e
$el+ !t to %o aail.
T#e %it !e(ore t#e $el+ )aloi" 0rote "eeral
letter".
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T#e"e letter" to #i" (rie%$" le%$ "**ort to t#e
t#eory t#at #e 0a" (rame$ !y t#e royali"t". He 0rotet#at #e 0a" c#alle%&e$ !y t0o o( t#e royali"t" a%$
t#at t#ey #a$ *t #im o% #i" #o%or %ot to tell #i"
re*!lica% (rie%$" a!ot t#e $el. I $ie t#e ictim o(
a% i%(amo" coette. It i" i% a mi"era!le !ra0l t#at
my li(e i" e7ti%&i"#e$. O#+ 0#y $ie (or "o triial a
t#i%&+ 0#y $ie (or "omet#i%& "o $e"*ica!le Bt
mo"t o( t#at la"t %it !e(ore t#e $el+ )aloi"
care(lly *t $o0% o% *a*er #i" e%tire mat#ematical
t#eory+ a%$ "e%t it to #i" (rie%$ A&"te C#ealier. At
$a0% o% May 3/+ ,>3@+ )aloi" (ace$ #i" c#alle%&er o%
a $e"erte$ el$. He 0a" "#ot i% t#e "tomac# a%$ le(tlyi%& i% a&o%y alo%e i% t#e el$. 1o o%e !ot#ere$ to
call a $octor. Fi%ally a *ea"a%t (o%$ #im a%$
!rot #im to t#e #o"*ital+ 0#ere #e $ie$ t#e %e7t
mor%i%&. He 0a" t0e%ty year" ol$. I% ,>4+ t#e
mat#ematicia% o"e*# Lioille e$ite$ a%$ *!li"#e$
)aloi"' ele&a%t mat#ematical t#eory i% a or%al.
)aloi"' t#eory 0ol$ "**ly t#e crcial "te* i% t#e
met#o$ "e$ a ce%try a%$ a #al( later i% attacki%&
Fermat'" La"t T#eorem.
nother GictimCac#y'" carele""%e"" a%$ arro&a%ce ri%e$ t#e li(e
o( at lea"t o%e ot#er !rillia%t mat#ematicia%. 1iel"
He%rik A!el ,>/@=,>@6 0a" t#e "o% o( t#e *a"tor o(
t#e illa&e o( Fi%$o i% 1or0ay. 9#e% #e 0a" "i7tee%+
a teac#er e%cora&e$ A!el to rea$ )a""' (amo"
!ook+ t#e 9iscjuisitiones* A!el 0a" ee% "cce""(l i%
lli%& i% "ome &a*" i% t#e *roo(" o( "ome o( t#e
t#eorem". Bt t0o year" later+ #i" (at#er $ie$ a%$
yo%& A!el #a$ to *o"t*o%e #i" "t$y o( mat#ematic"
a%$ co%ce%trate #i" eNort" o% "**orti%& t#e (amily.
I% "*ite o( t#e &reat $i
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(ace$+ A!el ma%a&e$ to co%ti%e "ome "t$y o(
mat#ematic" a%$ ma$e a remarka!le mat#ematical
$i"coery at t#e a&e o( %i%etee%. He *!li"#e$ a
*a*er i% ,>@ i% 0#ic# #e *roe$ t#at %o "oltio%
0a" *o""i!le (or eatio%" o( t#e (t# $e&ree. A!el
#a$ t#" "ole$ o%e o( t#e mo"t cele!rate$ *ro!lem"
o( #i" $ay. 2et t#e &i(te$ yo%& mat#ematicia% #a$
"till %ot !ee% oNere$ a% aca$emic *o"itio%+ 0#ic# #e
!a$ly %ee$e$ to "**ort #i" (amily a%$ "o #e "e%t #i"
0ork to Cac#y (or ealatio% a%$ *o""i!le
*!licatio% a%$ reco&%itio%. T#e .*a*er A!el "e%t
Cac#y 0a" o( e7traor$i%ary *o0er a%$ &e%erality.
Bt Cac#y lo"t it. 9#e% it a**eare$ i% *ri%t+ year"
later+ it 0a" mc# too late to #el* A!el. I% ,>@6 A!el
$ie$ (rom t!erclo"i"+ !rot o% !y *oerty a%$
t#e "trai% o( "**orti%& #i" (amily i% $ire
circm"ta%ce". T0o $ay" a(ter #i" $eat#+ a letter
arrie$ a$$re""e$ to A!el i%(ormi%& #im #e #a$ !ee%
a**oi%te$ *ro(e""or at t#e ;%ier"ity o( Berli%.
T#e co%ce*t o( a% A!elia% )ro* %o0 co%"i$ere$ a
0or$ a%$ 0ritte% 0it# a "mall a+ a!elia% i" ery
im*orta%t i% mo$er% al&e!ra a%$ i" a crcial eleme%t
i% t#e mo$er% treatme%t o( t#e Fermat *ro!lem. A%
a!elia% &ro* i" o%e 0#ere t#e or$er o( mat#ematical
o*eratio%" ca% !e reer"e$ 0it#ot aNecti%& t#e
otcome. A% a!elia% ariety i" a% ee% more a!"tract
al&e!raic e%tity+ a%$ it" "e 0a" al"o im*orta%t i%
mo$er% a**roac#e" to t#e "oltio% o( Fermat'" La"t
T#eorem.
9e)ekin),s ()eals
T#e le&acy o( Carl Frie$ric# )a"" co%ti%e$ t#ro
t#e ce%trie". O%e o( )a""' mo"t %ota!le
mat#ematical "cce""or" 0a" Ric#ar$ De$eki%$
,>3,=,6,4+ !or% i% t#e "ame
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to0% a" t#e &reat ma"ter+ i% Br%"0ick+ )erma%y.
;%like )a""+ #o0eer+ a" a c#il$ De$eki%$ "#o0e$
%o &reat i%tere"t i% or ca*acity (or mat#ematic". He
0a" more i%tere"te$ i% *#y"ic" a%$ c#emi"try+ a%$
"a0 mat#ematic" a" a "era%t to t#e "cie%ce". Bt at
t#e a&e o( "ee%tee%+ De$eki%$ e%tere$ t#e "ame
"c#ool 0#ere t#e &reat )a"" &ot #i" mat#ematical
trai%i%&Caroli%e Colle&ea%$ t#ere #i" (tre
c#a%&e$. De$eki%$ !ecame i%tere"te$ i%
mat#ematic" a%$ #e *r"e$ t#at i%tere"t i%
)otti%&e%+ 0#ere )a"" 0a" teac#i%&. I% ,>-@+ at t#e
a&e o( @,+ Ric#ar$ De$eki%$ receie$ #i" $octorate
(rom )a"". T#e ma"ter (o%$ #i" **il'" $i""ertatio%
o% t#e calcl" com*letely "ati"(yi%&. T#i" 0a" %ot
"c# a &reat com*lime%t+ a%$ i% (act De$eki%$'"
&e%i" #a$ %ot yet !e&% to ma%i(e"t it"el(.
I% ,>-+ De$eki%$ 0a" a**oi%te$ a lectrer i%
)otti%&e%. 9#e% )a"" $ie$ i% ,>-- a%$ Diric#let
moe$ (rom Berli% to take #i" *o"itio%+ De$eki%$
atte%$e$ all o( Diric#let'" lectre" at )otti%&e% a%$
e$ite$ t#e latter'" *io%eeri%& treati"e o% %m!er
t#eory+ a$$i%& a "**leme%t !a"e$ o% #i" o0% 0ork.
T#i" "**leme%t co%tai%e$ a% otli%e o( t#e t#eory
De$eki%$ $eelo*e$ (or al&e!raic %m!er"+ 0#ic#
are $e%e$ a" "oltio%" o( al&e!raic eatio%". T#ey
co%tai% mlti*le" o( "are root" o( %m!er" alo%&
0it# ratio%al %m!er". Al&e!raic %m!er el$" are
ery im*orta%t i% t#e "t$y o( Fermat'" eatio%+ a"
t#ey ari"e (rom t#e "oltio% o( ario" ki%$" o(
eatio%". De$eki%$ t#" $eelo*e$ a "i&%ica%t
area 0it#i% %m!er t#eory.
De$eki%$'" &reate"t co%tri!tio% to t#e mo$er%
a**roac# to Fermat'" la"t T#eorem 0a" #i"
$eelo*me%t o( t#e t#eory o( i$eal"+ a!"tractio%" o(
mmer'" i$eal %m!er". A ce%try
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a(ter t#eir $eelo*me%t !y De$eki%$+ i$eal" 0ol$
i%"*ire Barry Mazr+ a%$ Mazr'" o0% 0ork 0ol$ !ee7*loite$ !y A%$re0 9ile".
I% t#e ,>-?=> aca$emic year+ Ric#ar$ De$eki%$
&ae t#e r"t mat#ematic" cor"e o% )aloi" t#eory.
De$eki%$'" %$er"ta%$i%& o( mat#ematic" 0a" ery
a!"tract+ a%$ #e eleate$ t#e t#eory o( &ro*" to t#e
mo$er% leel at 0#ic# it i" %$er"too$ a%$ tat
to$ay. A!"tractio% ma$e t#e t0e%tiet#=ce%try
a**roac# to Fermat'" *ro!lem *o""i!le. De$eki%$'"
&ro%$!reaki%& cor"e o% t#e t#eorie" $eelo*e$ !y
)aloi" 0a" a &reat "te* i% t#i" $irectio%. T#e cor"e
0a" atte%$e$ !y t0o "t$e%t".T#e% De$eki%$'" career took a "tra%&e tr%. He le(t
)otti%&e% (or a *o"itio% i% Zric#+ a%$ a(ter e
year"+ i% ,>4@+ #e retr%e$ to Br%"0ick+ 0#ere #e
tat at a #i "c#ool (or (ty year". 1o $%e #a"
!ee% a!le to e7*lai% 0#y a !rillia%t mat#ematicia%
0#o !rot al&e!ra to a% i%cre$i!ly #i leel o(
a!"tractio% a%$ &e%erality "$$e%ly le(t o%e o( t#e
mo"t *re"ti&io" *o"itio%" at a%y Ero*ea%
%ier"ity to teac# at a% %k%o0% #i "c#ool.
De$eki%$ %eer marrie$ a%$ lie$ (or ma%y year"
0it# #i" "i"ter. He $ie$ i% ,6,4+ a%$ mai%tai%e$ a"#ar*+ actie mi%$ to #i" la"t $ay.
8in )e Siecle
At t#e tr% o( t#e %i%etee%t# ce%try+ t#ere lie$ i%
Fra%ce a mat#ematicia% o( &reat a!ility i% a
"r*ri"i%&ly 0i$e ariety o( area". T#e !rea$t# o(
k%o0le$&e o( He%ri Poi%care ,>-=,6,@ e7te%$e$
!eyo%$ mat#ematic". I% ,6/@ a%$ later+ 0#e% #e 0a"
alrea$y a re%o0%e$ mat#ematicia%+ Poi%care 0rote
*o*lar
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!ook" o% mat#ematic". T#e"e *a*er!ack"+ rea$ !y
*eo*le o( all a&e"+ 0ere a commo% "it i% t#e ca(e"
a%$ t#e *ark" o( Pari".
Poi%care 0a" !or% to a (amily o( &reat ac#ieer".
Hi" co"i%+ Raymo%$ Poi%care+ ro"e to !e t#e
*re"i$e%t o( Fra%ce $ri%& t#e Fir"t 9orl$ 9ar. Ot#er
(amily mem!er" #el$ &oer%me%t a%$ *!lic "erice
*o"itio%" i% Fra%ce a" 0ell.
From a yo%& a&e+ He%ri $i"*laye$ a *o0er(l
memory. He col$ recite (rom a%y *a&e o( a !ook #e
rea$. Hi" a!"e%tmi%$=e$%e""+ #o0eer+ 0a"
le&e%$ary. A Fi%%i"# mat#ematicia% o%ce came all
t#e 0ay to Pari" to meet 0it# Poi%care a%$ $i"c""
"ome mat#ematical *ro!lem". T#e i"itor 0a" ke*t
0aiti%& (or t#ree #or" ot"i$e Poi%care'" "t$y
0#ile t#e a!"e%tmi%$e$ mat#ematicia% *ace$ !ack
a%$ (ort#a" 0a" #i" #a!it t#root #i" 0orki%&
li(e. Fi%ally+ Poi%care *o**e$ #i" #ea$ i%to t#e
0aiti%& room a%$ e7claime$8 Sir+ yo are $i"tr!i%&
me *o% 0#ic# t#e i"itor "mmarily le(t+ %eer to
!e "ee% i% Pari" a&ai%.
Poi%care'" !rillia%ce 0a" reco&%ize$ 0#e% #e 0a"
i% eleme%tary "c#ool. Bt "i%ce #e 0a" "c# a
%ier"ali"ta re%ai""a%ce ma% i% t#e maki%i""*ecial a*tit$e (or mat#ematic" $i$ %ot yet
ma%i(e"t it"el(. He $i"ti%&i"#e$ #im"el( 0it# #i"
e7celle%ce i% 0riti%& at a% early a&e. A teac#er 0#o
reco&%ize$ a%$ e%cora&e$ #i" a!ility trea"re$ #i"
"c#ool *a*er". At "ome *oi%t+ #o0eer+ t#e
co%cer%e$ teac#er #a$ to catio% t#e yo%& &e%i"8
Do%'t $o "o 0ell+ *lea"e...try to !e more or$i%ary.
T#e teac#er #a$ &oo$ rea"o% to make t#i" "&&e"=
tio%. A**are%tly+ Fre%c# e$cator" #a$ lear%e$
"omet#i%& (rom t#e mi"(ort%e" o( )aloi" #al( a
ce%try earlierteac#er" (o%$ t#at &i(te$ "t$e%t"o(te% (aile$ at t#e #a%$" o( %i%"*ire$ e7ami%er".
Hi" teac#er 0a" &e%i%ely 0orrie$ t#at
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FERMAT'S LAST THEOREM
!o)ular 8orms
Poi%care "t$ie$ *erio$ic (%ctio%"+ "c# a" t#e "i%e"
a%$ co"i%e" o( Forier%ot o% t#e %m!er li%e a"
Forier #a$ $o%e+ !t i% t#e com*le7 *la%e. T#e "i%e
(%ctio%+ sin #- i" t#e ertical #eit o% a circle 0it#
ra$i" , 0#e% t#e a%&le i" 7. T#i" (%ctio% i" *erio$ic8
it re*eat" it"el( oer a%$ oer eery time t#e a%&lecom*lete" a mlti*le o( it" *erio$+ 34/ $e&ree". T#i"
*erio$icity i" a "ymmetry. Poi%care e7ami%e$ t#e
com*le7 *la%e+ 0#ic# co%tai%" real %m!er" o% t#e
#orizo%tal a7i" a%$ ima&i%ary o%e" o% t#e ertical o%e
a" "#o0% !elo0.
5ere, a periodic unction could be conceived as having a periodicity
both along the real a&is an) along the imaginary a&is. +oincare went
even urther and posited the e&istence o unctions with a wider
array o symmetries. These were unctions that remained
unchanged when the comple& variable z was changedaccording toOz20000000000000HjEaD$bIcD$)F* 5ere the elements a- b- c,
)- arranged as a matri&, ormed an algebraic grou'*This means
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t#at t#ere are i%%itely ma%y *o""i!leariatio%". T#ey all commte 0it# eac#
ot#er a%$ t#e (%ctio% i" invariant %$ert#i" &ro* o( tra%"(ormatio%". Poi%carecalle$ "c# 0eir$ (%ctio%" atomor*#ic
(orm".T#e atomor*#ic (orm" 0ere ery+ ery
"tra%&e creatre" "i%ce t#ey "ati"e$ma%y i%ter%al "ymmetrie". Poi%care
0a"%'t ite "re t#ey e7i"te$. Actally+
Poi%care $e"cri!e$ #i" re"earc# a"(ollo0". He "ai$ t#at (or (tee% $ay" #e
0ol$ 0ake * i% t#e mor%i%& a%$ "itat #i" $e"k (or a co*le o( #or" tryi%&
to co%i%ce #im"el( t#at t#e atomor*#ic(orm" #e i%e%te$ col$%'t *o""i!ly e7i"t.
O% t#e (tee%t# $ay+ #e realize$ t#at #e0a" 0ro%&. T#e"e "tra%&e (%ctio%"+
#ar$ to ima&i%e i"ally+ $i$ e7i"t.Poi%care e7te%$e$ t#em to ee% morecom*licate$ (%ctio%"+ calle$ mo$lar
(orm". T#e mo$lar (orm" lie o% t#e**er #al( o( t#e com*le7 *la%e+ a%$
t#ey #ae a #y*er!olic &eometry. T#ati"+ t#ey lie i% a "tra%&e "*ace 0#ere
t#e %o%=Ecli$ea% &eometry o( Bolyai a%$Lo!ac#e"ky rle". T#ro a%y *oi%t i%t#i" #al(=*la%e+ma%y li%e" *arallel to
a%y &ie% li%e e7i"t.
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Poi%care le(t !e#i%$ t#e "ymmetric
atomor*#ic (orm" a%$ t#eir ee% morei%tricate mo$lar (orm" a%$ 0e%t o% to
$o ot#er mat#ematic". He 0a" !"y i%"o ma%y el$"+ o(te% i% a (e0 o( t#emat o%ce+ t#at #e #a$ %o time to "it a%$
*o%$er t#e !eaty o( #ar$ly ima&i%a!le+i%%itely "ymmetric e%titie". Bt
%!ek%o0%"t to #im+ #e #a$ "t "o0e$a%ot#er "ee$ i% t#e &ar$e% t#at 0ol$
ee%tally !ri%& a!ot t#e Fermat"oltio%.
n Une#'ecte) 2onnection with a 9oughnut
I% ,6@@+ t#e America% mat#ematicia%Loi" . Mor$ell $i"coere$ 0#at #e
t#ot 0a" a ery "tra%&e co%%ectio%!et0ee%
The very strane !o"#$ar %or!s are sy!!etr&c &n !any 'ays '&th&n th&s s(ace. The sy!!etr&es are o)ta&ne" )y a""&n a n#!)
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t#e "oltio%" o( al&e!raic eatio%" a%$to*olo&y. T#e eleme%t" o( to*olo&y are"r(ace" a%$ "*ace". T#e"e "r(ace"
col$ !e i% a%y $ime%"io%8 t0o$ime%"io%"+ "c# a" t#e &re" i%
a%cie%t )reek &eometry+ or t#ey col$!e i% t#ree=$ime%"io%al "*ace+ or more.
To*olo&y i" a "t$y o( co%ti%o" (%c=tio%" t#at act o% t#e"e "*ace"+ a%$ t#e
*ro*ertie" o( t#e "*ace" t#em"ele". T#e*art o( to*olo&y 0#ic# co%cer%e$
Mor$ell 0a" t#e o%e o( "r(ace" i%t#ree=$ime%"io%al "*ace. A "im*lee7am*le o( "c# a "r(ace i" a "*#ere8
it i" t#e "r(ace o( a !all+ "c# a" a!a"ket!all. T#e !all i" t#ree=$ime%"io%al+
!t it" "r(ace a""mi%& %o $e*t# i" at0o=$ime%"io%al o!ect. T#e "r(ace o(t#e eart# i" a%ot#er e7am*le. T#e eart#
it"el( i" t#ree $ime%"io%al8 a%y *lace o%t#e eart# or i%"i$e it ca% !e &ie% !y
it" lo%&it$e o%e $ime%"io%+ it"
latit$e a "eco%$ $ime%"io%+ a%$ it"$e*t# t#e t#ir$ $ime%"io%. Bt t#e"r(ace o( t#e eart# %o $e*t# i" t0o=$ime%"io%al+ "i%ce a%y *oi%t o% t#e
"r(ace o( t#e eart# ca% !e "*ecie$ !yt0o %m!er"8 it" lo%&it$e a%$ it"
latit$e.T0o=$ime%"io%al "r(ace" i% t#ree=
$ime%"io%al "*ace ca% !e cla""ie$accor$i%& to t#eir &e%". T#e &e%" i"t#e %m!er o( #ole" i% t#e "r(ace. T#e
&e%" o( a "*#ere i" zero "i%ce t#ereare %o #ole" i% it. A $o%t #a" o%e
#ole i% it. T#ere(ore t#e &e%" o( a$o%t mat#ematically calle$ a tor"
i" o%e. A #ole mea%" a #ole t#at r%"com*letely t#ro t#e "r(ace. A c*0it# t0o #a%$le" #a" t0o #ole" t#ro
it. T#ere(ore it i" a "r(ace o( &e%"t0o.
A "r(ace o( o%e &e%" ca% !etra%"(orme$ !y a co%ti%o" (%ctio%
i%to a%ot#er "r(ace o( t#e "ame &e%".T#e o%ly 0ay to tra%"(orm a "r(ace o(
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