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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&ample, , 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&ample 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&ample, 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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    +

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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&amples 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&ample 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&ample 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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