an introduction to ramanujan's magic squares · an introduction to ramanujan’s magic squares...
TRANSCRIPT
An introduction toRamanujan’s magic squares
George P. H. Styan2
January 18, 2012
2This beamer file is for an invited talk presented as a video on Tuesday, 10 January 2012, at theInternational Workshop and Conference on Combinatorial Matrix Theory and Generalized Inverses of Matrices,Manipal University, Manipal (Karnataka), India, 2–11 January 2012. This research was supported, in part, by theNatural Sciences and Engineering Research Council of Canada.
George P. H. Styan3 Ramanujan’s magic squares
Acknowledgements: January 18, 2012 B3-01a
This beamer file is for an invited talk presented on Tuesday, 10 January 2012, atthe International Workshop and Conference on Combinatorial Matrix Theory andGeneralized Inverses of Matrices, Manipal University, Manipal (Karnataka), India,2–11 January 2012.
I am very grateful to Professor Prasad and the Workshop participants whoreminded me of Ramanujan’s work on magic squares and to Dr. B. Chaluvarajufor drawing our attention to “Bangalore University’s old collections in the librarywhich deal with Yantras and magic squares.”
In addition, many thanks go to Pavel Chebotarev and Ka Lok Chu for their help.This research was supported, in part, by the Natural Sciences and EngineeringResearch Council of Canada.
George P. H. Styan4 Ramanujan’s magic squares
Srinivasa Aiyangar Ramanujan (1887–1920) B3-01b
Srinivasa Aiyangar Ramanujan (1887–1920)
was born in Erode and lived in Kumbakonam
(both then in Madras Presidency, both now in Tamil Nadu),
and died in Chetput (Madras, now Chennai).
George P. H. Styan5 Ramanujan’s magic squares
Erode, Kumbakonam, Chennai B3-02a
George P. H. Styan6 Ramanujan’s magic squares
Kumbakonam (near Thanjavur) B3-02b
Ramanujan lived most of his life in Kumbakonam, an ancient capital of theChola Empire. The dozen or so major temples dating from this period made
Kumbakonam a magnet to pilgrims from throughout South India.
Raja Raja Chola I, popularly known as Raja Raja the Great,ruled the Chola Empire between 985 and 1014 CE.
George P. H. Styan7 Ramanujan’s magic squares
22 December = National Mathematics Day B3-03
Srinivasa Aiyangar Ramanujan was born on 22 December 1887,and on 22 December 1962 and on 22 December 2011,
India Post issued a postage stamp in his honour.
On 22 December 2011, Prime Minister Dr. Manmohan Singh in Chennaideclared 22 December as National Mathematics Day, and declared
2012 as National Mathematical Year. [The Hindu, 27 December 2011.]
George P. H. Styan8 Ramanujan’s magic squares
Gauss, Euler, Cauchy, Newton, and Archimedes B3-04
Ramanujan’s talent was said9 by the English mathematicianGodfrey Harold “G.H.” Hardy (1877–1947)
to be in the same league as that ofGauss, Euler, Cauchy, Newton, and Archimedes.
9“Srinivasa Ramanujan”, Wikipedia, 7 January 2012, p. 1.
George P. H. Styan10 Ramanujan’s magic squares
Trinity College, Cambridge, and G. H. Hardy B3-05
From 1914–1919 Ramanujan workedwith G. H. Hardy at Trinity College, Cambridge11.
12-01-07 7:51 PMG H Hardy
Page 1 of 1
11Photographs (left panel: Ramanujan, centre) from “Srinivasa Ramanujan”, Wikipedia, 7 January 2012, p. 8.
George P. H. Styan12 Ramanujan’s magic squares
Berndt 1985 B3-06
Ramanujan’s work on magic squaresis presented, in some detail, in
Chapter 1 (pp. 16–24) ofRamanujan’s Notebooks, Part I, byBruce C. Berndt (Springer 1985)
“The origin of Chapter 1probably is found in
Ramanujan’s early school daysand is therefore much earlier thanthe remainder of the notebooks.”
George P. H. Styan13 Ramanujan’s magic squares
Tata Institute 1957 B3-07
Ramanujan’s work on magic squares was also presented,photographed from its original form, inNotebooks of Srinivasa Ramanujan,
Volume I, Notebook 1, and Volume II, Notebook 2,pub. Tata Institute of Fundamental Research, Bombay, 1957.
George P. H. Styan14 Ramanujan’s magic squares
Ramanujan’s 3× 3 magic matrix B3-08
In Berndt 1985, Corollary 1, p. 17, we find:
In a 3× 3 magic square,the elements in the
middle row, middle column,and each [main] diagonal
are in arithmetic progression.
George P. H. Styan15 Ramanujan’s magic squares
Ramanujan’s 3× 3 magic matrix R3 B3-09
And so we have the general form for a 3× 3 magic matrix
R3 =
h + u h − u + v h − v
h − u − v h h + u + v
h + v h + u − v h − u
= hE3 + uU3 + vV3
= h
1 1 1
1 1 1
1 1 1
+ u
1 −1 0
−1 0 1
0 1 −1
+ v
0 1 −1
−1 0 1
1 −1 0
.
.
George P. H. Styan16 Ramanujan’s magic squares
Ramanujan’s 4× 4 magic matrix R4 B3-10
Berndt (op. cit., p. 21) presents
R4 =
a+ p d + s c + q b + r
c + r b + q a+ s d + p
b + s c + p d + r a+ q
d + q a+ r b + p c + s
=
a d c b
c b a d
b c d a
d a b c
+
p s q r
r q s p
s p r q
q r p s
,
the sum of two orthogonal Latin squares (Graeco-Latin square).
George P. H. Styan17 Ramanujan’s magic squares
Ramanujan’s 5× 5 magic square B3-11
Ramanujan (Tata Institute 1957, Volume II, Notebook 2, p. 12 = original p. 8)gives this 5× 5 magic square, which is also the
sum of two orthogonal Latin squares (Graeco-Latin square).
George P. H. Styan18 Ramanujan’s magic squares
Ramanujan’s 7× 7 and 8× 8 magic squares B3-12
Berndt (op. cit.) reports two 7× 7 (p. 24) and two 8× 8 (p. 22)magic squares (but apparently no 6× 6) by Ramanujan, including
R7 =
1 49 41 33 25 17 9
18 10 2 43 42 34 26
35 27 19 11 3 44 36
45 37 29 28 20 12 4
13 5 46 38 30 22 21
23 15 14 6 47 39 31
40 32 24 16 8 7 48
, R8 =
1 62 59 8 9 54 51 16
60 7 2 61 52 15 10 53
6 57 64 3 14 49 56 11
63 4 5 58 55 12 13 50
17 46 43 24 25 38 35 32
44 23 18 45 36 31 26 37
22 41 48 19 30 33 40 27
47 20 21 42 39 28 29 34
,
and says that R8 is “constructed from four 4× 4 magic squares”.
We find that R8 may be constructed from two 4× 4 magic squares.
George P. H. Styan19 Ramanujan’s magic squares
Ramanujan’s 8× 8 magic matrix R8 B3-13
The classic fully-magic Nasik (pandiagonal) matrix with magic sum m(R8) = 260
R8 =
1 62 59 8 9 54 51 16
60 7 2 61 52 15 10 53
6 57 64 3 14 49 56 11
63 4 5 58 55 12 13 50
17 46 43 24 25 38 35 32
44 23 18 45 36 31 26 37
22 41 48 19 30 33 40 27
47 20 21 42 39 28 29 34
=
R(11)8 04
04 04
+
04 R(12)8
04 04
+
04 04
R(21)8 04
+
04 04
04 R(22)8
,
where R(11)8 ,R(12)
8 ,R(21)8 ,R(22)
8 are 4× 4 fully-magic Nasik (pandiagonal) matriceseach with magic sum 130 = 1
2m(R8).
Moreover, the magic matrices R(11)8 ,R(12)
8 ,R(21)8 ,R(22)
8 are interchangeable and sothere are 4! = 24 fully-magic Nasik (pandiagonal) 8× 8 matrices like R8.
George P. H. Styan20 Ramanujan’s magic squares
Ramanujan’s 4× 4 magic submatrices R(11)8 ,R(12)
8 ,R(21)8 ,R(22)
8 B3-14a
Furthermore,
R(12)8 = R(11)
8 + 8X, R(21)8 = R(11)
8 + 16X, R(22)8 = R(11)
8 + 24X,
where the fully-magic Nasik (pandiagonal) 4× 4 matrices
R(11)8 =
1 62 59 8
60 7 2 61
6 57 64 3
63 4 5 58
, X =
1 −1 −1 1
−1 1 1 −1
1 −1 −1 1
−1 1 1 −1
,
with magic sums m(R(11)8 ) = 1
2m(R8) = 130 and m(X) = 0. And so we may writeRamanujan’s 8× 8 magic matrix as the sum of two Kronecker products:
R8 =
1 62 59 8 9 54 51 16
60 7 2 61 52 15 10 53
6 57 64 3 14 49 56 11
63 4 5 58 55 12 13 50
17 46 43 24 25 38 35 32
44 23 18 45 36 31 26 37
22 41 48 19 30 33 40 27
47 20 21 42 39 28 29 34
=(1 1
1 1
)⊗ R(11)
8 + 8(0 1
2 3
)⊗ X.
George P. H. Styan21 Ramanujan’s magic squares
Ramanujan’s magic matrix R8 and the Agrippa magic matrix A4 B3-14b
The 4× 4 magic-basis matrix
B4 =
−3 1 1 −3
1 −1 −1 1
−1 1 1 −1
3 −1 −1 3
= −DX,
where
D =
3 0 0 0
0 1 0 0
0 0 1 0
0 0 0 3
, while X =
1 −1 −1 1
−1 1 1 −1
1 −1 −1 1
−1 1 1 −1
is the doubly-balanced 4× 4 magic matrix used in our “two-Kronecker-productsconstruction” of Ramanujan’s 8× 8 magic matrix R8. The 4× 4 Agrippa–Cardanomagic matrix
A4 = 12
(4B4 − B′
4 + (42 + 1)E4)=
4 14 15 1
9 7 6 12
5 11 10 8
16 2 3 13
.
George P. H. Styan22 Ramanujan’s magic squares
The Man Who Knew Infinity B3-15
For a“model of the biographer’s art”
we recommend
The Man who Knew Infinity:A Life of the Genius Ramanujan,
by Robert Kanigel,pub. Charles Scribner’s Sons 1991;Washington Square Press 1992
George P. H. Styan23 Ramanujan’s magic squares
The Man Who Knew Infinity B3-16
12-01-07 4:17 PMTHE MAN WHO KNEW INFINITY: A Life of the Genius Ramanujan - Robert Kanigel
Page 2 of 4http://www.robertkanigel.com/_i__b_the_man_who_knew_infinity__b___a_life_of_the_genius_ramanujan__i__58016.htm
Book-of-the-Month Club selectionQuality Paperback Book Club selectionNational Book Critics Circle Award finalist, 1992Los Angeles Times Book Prize finalist, 1991Library Journal, Best Sci-Tech Books of 1991New York Public Library, Book to Remember, 1991New York Times Book Review, Notable Books of the Year,1991Film option held by Matt Brown/Edward R. Pressman
Selected reviews: Kirkus (starred), Publisher's Weekly, Booklist(starred), New York Times, New York Times Book Review, LosAngeles Times, Christian Science Monitor, San FranciscoChronicle, Boston Phoenix, Washington Post, New York Review ofBooks, Byte, Science, Indian Express (India), New Scientist,Virginia Quarterly Review, American Mathematical Monthly, TheIndependent (U.K.), Times Literary Supplement (U.K.), FarEastern Economic Review, American Scientist, Isis, SewaneeReview
Original Scribners hardcover edition, 1991
"A fascinating account of Ramanujan's life which reads like asad romantic novel." -- Julius Axelrod, Nobel laureate
"This is the best biography of a mathematician, in fact of anyscientist, that I have ever read." -- Bruce Berndt, Universityof Illinois
"Enthralling...One of the best scientific biographies I've everseen." -- John Gribbin, author of In Search of Schrodinger's Cat
-- From the dustjacket of the Scribner's hardcover edition,1991
challenging philosophical ideasthat is actually a compelling read."-- Los Angeles Times
"One of the finest, bestdocumented biographies everpublished about a modernmathematician." -- MartinGardner, Raleigh News andObserver
"The most luminous expressionever of two three-dimensionallives along both personal andprofessional axes. As apresentation of genius interactingwith genius, I've seen nothing tocompare with it." -- Hugh Kenner,Byte
"A superbly craftedbiography...[Kanigel's] exceptionaltriumph is in the telling of thiswonderful human story." -- Science
"Even a complete innumerate canenjoy Mr. Kanigel's richly detailedbook...Kanigel desmontratesconsiderable psychologicalacumen in his portait of the twocentral figures...A thoroughlycaptivating book." -- New YorkTimes Book Review
"An extraordinary compellingbiography, richly textured withsocial, psychological, personal,and mathematical details...Awarm, romantic tale that wouldbe beyond the scope ofimagination were it not, after all,true. [Other] reviewers justlypraise this book as one of the bestscientific biographies everwritten." -- American MathematicalMonthly
"Perspicacious, informed,imaginative, [The Man Who KnewInfinity] is to my mind the bestmathematical biography I haveever read...[It]is not just a brilliantbiography of Ramanujan, thegenius born in a hovel. Nor is it a'life and works,' part one Life, parttwo Works. It is a sensitive andintimate portrait of Ramanujan,the human being, who lived formathematics....You do not need tohave any sympathy at all withmathematics to read The Man Who
12-0
1-07
4:1
7 PM
THE
MAN
WH
O K
NEW
INFI
NIT
Y: A
Life
of t
he G
eniu
s Ra
man
ujan
- R
ober
t Kan
igel
Page
2 o
f 4ht
tp:/
/ww
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ober
tkan
igel
.com
/_i_
_b_t
he_m
an_w
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_inf
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__b_
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ujan
__i_
_580
16.h
tm
Book
-of-
the-
Mon
th C
lub
sele
ctio
nQ
ualit
y Pa
perb
ack
Book
Clu
b se
lect
ion
Nat
iona
l Boo
k C
ritic
s C
ircle
Aw
ard
final
ist,
1992
Los
Ang
eles
Tim
es B
ook
Priz
e fin
alis
t, 19
91Li
brar
y Jo
urna
l, Be
st S
ci-T
ech
Book
s of
199
1N
ew Y
ork
Publ
ic L
ibra
ry, B
ook
to R
emem
ber,
1991
New
Yor
k Ti
mes
Boo
k Re
view
, Not
able
Boo
ks o
f the
Yea
r,19
91Fi
lm o
ptio
n he
ld b
y M
att B
row
n/Ed
war
d R.
Pre
ssm
an
Sele
cted
revi
ews:
Kirk
us (s
tarr
ed),
Publ
isher
's W
eekl
y, B
ookl
ist(s
tarr
ed),
New
Yor
k Ti
mes
, New
Yor
k Ti
mes
Boo
k Re
view
, Los
Ang
eles
Tim
es, C
hrist
ian
Scien
ce M
onito
r, S
an F
ranc
isco
Chro
nicle
, Bos
ton
Phoe
nix,
Was
hing
ton
Post
, New
Yor
k Re
view
of
Book
s, By
te, S
cienc
e, In
dian
Exp
ress
(Ind
ia),
New
Scie
ntist
,V
irgin
ia Q
uart
erly
Rev
iew, A
mer
ican
Mat
hem
atica
l Mon
thly
, The
Inde
pend
ent (
U.K
.), T
imes
Lite
rary
Sup
plem
ent (
U.K
.), F
arEa
ster
n Ec
onom
ic Re
view
, Am
erica
n Sc
ientis
t, Is
is, S
ewan
eeRe
view O
rigin
al S
crib
ners
har
dcov
er ed
ition
, 199
1
"A fa
scin
atin
g ac
coun
t of R
aman
ujan
's lif
e w
hich
read
s lik
e a
sad
rom
antic
nov
el."
-- Ju
lius
Axe
lrod,
Nob
el la
urea
te
"Thi
s is
the
best
bio
grap
hy o
f a m
athe
mat
icia
n, in
fact
of a
nysc
ient
ist,
that
I ha
ve e
ver r
ead.
" -- B
ruce
Ber
ndt,
Uni
vers
ityof
Illin
ois
"Ent
hral
ling.
..One
of t
he b
est s
cien
tific
bio
grap
hies
I've
eve
rse
en."
-- Jo
hn G
ribbi
n, a
utho
r of
In S
earc
h of
Sch
rodi
nger
's C
at
-- F
rom
the
dust
jack
et o
f the
Scr
ibne
r's h
ardc
over
edi
tion,
1991
chal
leng
ing
philo
soph
ical
idea
sth
at is
act
ually
a c
ompe
lling
read
."--
Los
Ang
eles
Tim
es
"One
of t
he fi
nest
, bes
tdo
cum
ente
d bi
ogra
phie
s ev
erpu
blis
hed
abou
t a m
oder
nm
athe
mat
icia
n." -
- Mar
tinG
ardn
er, R
alei
gh N
ews a
ndO
bser
ver
"The
mos
t lum
inou
s ex
pres
sion
ever
of t
wo
thre
e-di
men
sion
alliv
es a
long
bot
h pe
rson
al a
ndpr
ofes
sion
al a
xes.
As
apr
esen
tatio
n of
gen
ius
inte
ract
ing
with
gen
ius,
I've
seen
not
hing
toco
mpa
re w
ith it
." --
Hug
h K
enne
r,By
te
"A s
uper
bly
craf
ted
biog
raph
y...[
Kan
igel
's] e
xcep
tiona
ltr
ium
ph is
in th
e te
lling
of t
his
won
derf
ul h
uman
sto
ry."
-- S
cienc
e
"Eve
n a
com
plet
e in
num
erat
e ca
nen
joy
Mr.
Kan
igel
's ric
hly
deta
iled
book
...K
anig
el d
esm
ontr
ates
cons
ider
able
psy
chol
ogic
alac
umen
in h
is p
orta
it of
the
two
cent
ral f
igur
es...
A th
orou
ghly
capt
ivat
ing
book
." --
New
Yor
kTi
mes
Boo
k Re
view
"An
extr
aord
inar
y co
mpe
lling
biog
raph
y, ri
chly
text
ured
with
soci
al, p
sych
olog
ical
, per
sona
l,an
d m
athe
mat
ical
det
ails
...A
war
m, r
oman
tic ta
le th
at w
ould
be b
eyon
d th
e sc
ope
ofim
agin
atio
n w
ere
it no
t, af
ter
all,
true
. [O
ther
] rev
iew
ers
just
lypr
aise
this
boo
k as
one
of t
he b
est
scie
ntifi
c bi
ogra
phie
s ev
erw
ritte
n." -
- Am
erica
n M
athe
mat
ical
Mon
thly
"Per
spic
acio
us, i
nfor
med
,im
agin
ativ
e, [T
he M
an W
ho K
new
Infin
ity] i
s to
my
min
d th
e be
stm
athe
mat
ical
bio
grap
hy I
have
ever
read
...[It
]is n
ot ju
st a
bril
liant
biog
raph
y of
Ram
anuj
an, t
hege
nius
bor
n in
a h
ovel
. Nor
is it
a'li
fe a
nd w
orks
,' pa
rt o
ne L
ife, p
art
two
Wor
ks. I
t is
a se
nsiti
ve a
ndin
timat
e po
rtra
it of
Ram
anuj
an,
the
hum
an b
eing
, who
live
d fo
rm
athe
mat
ics..
..You
do
not n
eed
toha
ve a
ny s
ympa
thy
at a
ll w
ithm
athe
mat
ics
to re
ad T
he M
an W
ho
12-01-07 4:17 PMTHE MAN WHO KNEW INFINITY: A Life of the Genius Ramanujan - Robert Kanigel
Page 4 of 4http://www.robertkanigel.com/_i__b_the_man_who_knew_infinity__b___a_life_of_the_genius_ramanujan__i__58016.htm
Times Literary Supplement
"This is the first comprehensivebiography [of Ramanujan] and islikely to remain the canonicalreference book for all aspects ofhis brief life for many years tocome...[I] can recommend itwholeheartedly to bothmathematicians and to generalreaders." -- The MathematicalGazette
"Poignant and absorbing." --
German edition, Verlag Vieweg,1993
Original Washington SquarePress paperback edition, 1992
12-0
1-07
4:1
7 PM
THE
MAN
WH
O K
NEW
INFI
NIT
Y: A
Life
of t
he G
eniu
s Ra
man
ujan
- R
ober
t Kan
igel
Page
4 o
f 4ht
tp:/
/ww
w.r
ober
tkan
igel
.com
/_i_
_b_t
he_m
an_w
ho_k
new
_inf
inity
__b_
__a_
life_
of_t
he_g
eniu
s_ra
man
ujan
__i_
_580
16.h
tm
Tim
es L
itera
ry S
uppl
emen
t
"Thi
s is
the
first
com
preh
ensi
vebi
ogra
phy
[of R
aman
ujan
] and
islik
ely
to re
mai
n th
e ca
noni
cal
refe
renc
e bo
ok fo
r all
aspe
cts
ofhi
s br
ief l
ife fo
r man
y ye
ars
toco
me.
..[I]
can
reco
mm
end
itw
hole
hear
tedl
y to
bot
hm
athe
mat
icia
ns a
nd to
gen
eral
read
ers."
-- T
he M
athe
mat
ical
Gaz
ette
"Poi
gnan
t and
abs
orbi
ng."
--
Ger
man
edi
tion,
Ver
lag
Vie
weg
,19
93 Orig
inal
Was
hing
ton
Squa
rePr
ess
pape
rbac
k ed
ition
, 199
2
George P. H. Styan24 Ramanujan’s magic squares
The Man Who Knew Infinity B3-17
1 Scribner’s hardcover, 19912 U.K. hardcover, Scribner’s, 19913 Washington Square Press paperback, 19924 U.K. paperback, Abacus, 19925 Indian edition, Rupa, 19926 German edition, Vieweg Verlag, 19937 Cassette book, National Library for the Blind, 19938 Japanese edition, Kousakusha, 19949 Korean edition, Science Books, 200010 Chinese editions, Shanghai Scientific, 2002, 200811 Italian edition, Rizzoli, 200312 Thai edition, Matichon, 200713 Audio edition, Blackstone Audio, 200714 Greek edition, Travlos, 2008
George P. H. Styan25 Ramanujan’s magic squares
Der das Unendliche kannte; L’uomo che vide l’infinito B3-18
12-01-07 4:17 PMTHE MAN WHO KNEW INFINITY: A Life of the Genius Ramanujan - Robert Kanigel
Page 4 of 4http://www.robertkanigel.com/_i__b_the_man_who_knew_infinity__b___a_life_of_the_genius_ramanujan__i__58016.htm
Times Literary Supplement
"This is the first comprehensivebiography [of Ramanujan] and islikely to remain the canonicalreference book for all aspects ofhis brief life for many years tocome...[I] can recommend itwholeheartedly to bothmathematicians and to generalreaders." -- The MathematicalGazette
"Poignant and absorbing." --
German edition, Verlag Vieweg,1993
Original Washington SquarePress paperback edition, 1992
12-0
1-07
4:1
7 PM
THE
MAN
WH
O K
NEW
INFI
NIT
Y: A
Life
of t
he G
eniu
s Ra
man
ujan
- R
ober
t Kan
igel
Page
4 o
f 4ht
tp:/
/ww
w.r
ober
tkan
igel
.com
/_i_
_b_t
he_m
an_w
ho_k
new
_inf
inity
__b_
__a_
life_
of_t
he_g
eniu
s_ra
man
ujan
__i_
_580
16.h
tm
Tim
es L
itera
ry S
uppl
emen
t
"Thi
s is
the
first
com
preh
ensi
vebi
ogra
phy
[of R
aman
ujan
] and
islik
ely
to re
mai
n th
e ca
noni
cal
refe
renc
e bo
ok fo
r all
aspe
cts
ofhi
s br
ief l
ife fo
r man
y ye
ars
toco
me.
..[I]
can
reco
mm
end
itw
hole
hear
tedl
y to
bot
hm
athe
mat
icia
ns a
nd to
gen
eral
read
ers."
-- T
he M
athe
mat
ical
Gaz
ette
"Poi
gnan
t and
abs
orbi
ng."
--
Ger
man
edi
tion,
Ver
lag
Vie
weg
,19
93 Orig
inal
Was
hing
ton
Squa
rePr
ess
pape
rbac
k ed
ition
, 199
2
12-01-07 4:17 PMTHE MAN WHO KNEW INFINITY: A Life of the Genius Ramanujan - Robert Kanigel
Page 3 of 4http://www.robertkanigel.com/_i__b_the_man_who_knew_infinity__b___a_life_of_the_genius_ramanujan__i__58016.htm
Italian edition, L'uomo che vide l'infinito, Rizzoli,2003
Japanese hardcover edition, Kousakusha, 1994
mathematics to read The Man WhoKnew Infinity with pleasure; but bythe time you have finished it,some of Ramanujan's love of hissubject will probably have rubbedoff on you, and you will havebegun to appreciate the hypnoticfascination that it exerts uponthose who make it their life'swork." -- New York Review of Books
Washington Square Presspaperback, 1992
Abacus paperback edition [U.K.],1992
Review Excerpts, U.K.Edition
"This is a fine example of a workof popularising mathematics, anddeserves a wide readership." --New Scientist
A "fascinating biography...Kanigelhas written an exciting andthoughtful book." -- TheIndependent
"This is a grand read, enthrallingin every paragraph...the sort ofbook that makes you realise whata marvellous thing it is to behuman." -- Huddershield DailyExaminer
"A noteworthy performance." --Times Literary Supplement
12-0
1-07
4:1
7 PM
THE
MAN
WH
O K
NEW
INFI
NIT
Y: A
Life
of t
he G
eniu
s Ra
man
ujan
- R
ober
t Kan
igel
Page
3 o
f 4ht
tp:/
/ww
w.r
ober
tkan
igel
.com
/_i_
_b_t
he_m
an_w
ho_k
new
_inf
inity
__b_
__a_
life_
of_t
he_g
eniu
s_ra
man
ujan
__i_
_580
16.h
tm
Italia
n ed
ition
, L'u
omo
che
vide
l'in
finito
, Riz
zoli,
2003
Japa
nese
har
dcov
er e
ditio
n, K
ousa
kush
a, 1
994
mat
hem
atic
s to
read
The
Man
Who
Knew
Infin
ity w
ith p
leas
ure;
but
by
the
time
you
have
fini
shed
it,
som
e of
Ram
anuj
an's
love
of h
issu
bjec
t will
pro
babl
y ha
ve ru
bbed
off o
n yo
u, a
nd y
ou w
ill h
ave
begu
n to
app
reci
ate
the
hypn
otic
fasc
inat
ion
that
it e
xert
s up
onth
ose
who
mak
e it
thei
r lif
e'sw
ork.
" -- N
ew Y
ork
Revi
ew o
f Boo
ks
Was
hing
ton
Squa
re P
ress
pape
rbac
k, 1
992
Aba
cus
pape
rbac
k ed
ition
[U.K
.],19
92 Rev
iew
Exc
erpt
s, U
.K.
Editi
on
"Thi
s is
a fi
ne e
xam
ple
of a
wor
kof
pop
ular
isin
g m
athe
mat
ics,
and
dese
rves
a w
ide
read
ersh
ip."
--N
ew S
cient
ist
A "f
asci
natin
g bi
ogra
phy.
..Kan
igel
has
writ
ten
an e
xciti
ng a
ndth
ough
tful b
ook.
" -- T
heIn
depe
nden
t
"Thi
s is
a g
rand
read
, ent
hral
ling
in e
very
par
agra
ph...
the
sort
of
book
that
mak
es y
ou re
alis
e w
hat
a m
arve
llous
thin
g it
is to
be
hum
an."
-- H
udde
rshi
eld D
aily
Exam
iner
"A n
otew
orth
y pe
rfor
man
ce."
--Ti
mes
Lite
rary
Sup
plem
ent
George P. H. Styan26 Ramanujan’s magic squares
Prasantha Chandra Mahalanobis (1893–1972) B3-19
In The Man who Knew Infinity we learn that (Prologue, pp. 1–2):
One day in the summer of 1913, a twenty-year-old Bengalifrom an old and prosperous Calcutta family stood
in the chapel of King’s College, Cambridge, England.
Prasantha Chandra Mahalanobis (1893–1972) was smitten.
George P. H. Styan27 Ramanujan’s magic squares
Mahalanobis (1893–1972) & Ramanujan (1887–1920) B3-20
Scarcely off the boat from India and planning to study in London,Mahalanobis had come up to Cambridge
on the train for the day to sightsee.
The next day he met with the provost, and soon,to his astonishment and delight, he was a student at
King’s College, Cambridge.
He had been at Cambridge for about six monthswhen his mathematics tutor asked him,
“Have you met your wonderful countryman Ramanujan?”
He had not yet met him, but he had heard of him.
George P. H. Styan28 Ramanujan’s magic squares
Are you warm at night? asked Mahalanobis B3-21
Soon Mahalanobis did meet Ramanujan, and the two became friends;on Sunday mornings, after breakfast, they’d go for long walks,
talk about life, philosophy, mathematics.
Later, looking back, Mahalanobis would date the flowering of theirfriendship to one day in the fall following Ramanujan’s arrival.
He’d gone to see him at his place in Whewell’s Court.Cambridge was deserted. And cold.
Are you warm at night? asked Mahalanobis,seeing Ramanujan beside the fire.
No, replied the mathematician from always-warm Madras,he slept with his overcoat on, wrapped in a shawl.
George P. H. Styan29 Ramanujan’s magic squares
Sarangapani Street, Kumbakonam & Whewell’s Court, Cambridge B3-22
Until early 1914 Ramanujan lived in a traditional home onSarangapani Street in Kumbakonam. The family home is now a museum.
From 1914–1919 Ramanujan lived in Whewell’s Court, a 5-minute walk fromHardy’s rooms. Whewell’s Court was a 3-story stone warren of rooms laced witharched Gothic windows and pierced at intervals by staircases leading to rooms.
George P. H. Styan30 Ramanujan’s magic squares
Ramanujan had enough blankets B3-23
Figuring his friend hadn’t enough blankets,Mahalanobis stepped back into the little sleeping alcove
on the other side of the fireplace.
The bedspread was loose, as if Ramanujan had just gotten up.Yet the blankets lay perfectly undisturbed,
tucked neatly under the mattress.
Yes, Ramanujan had enough blankets;he just didn’t know what to do with them.
Gently, patiently, Mahalanobis showed him how you peeled them back,made a little hollow for yourself, slipped inside ...
George P. H. Styan31 Ramanujan’s magic squares
Ramanujan: the one superlatively great mathematician B3-24
For five years, walled off from India by World War One (1914–1918),Ramanujan would remain in strange, cold, distant England, fashioning,
through 21 major papers, an enduring mathematical legacy.
Then, he would go home to India to a hero’s welcome.
“Srinivasa Ramanujan”, an Englishman would later say of him,“was a mathematician so great that his name transcends jealousies,
the one superlatively great mathematician whomIndia has produced in the last thousand years.”
George P. H. Styan32 Ramanujan’s magic squares