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Ramanujan -- a Genius Par Excellence.
Ramanujan -- a Genius Par Excellence
-Dr.S.SelvaRani
Srinivasa Ramanujan
has hailed
as a natural
mathematical genius from our land.
He made substantial contributions
to the analytical theory of numbers and worked on elliptic functions,
continued fractions and infinite series.
Ramanjuan
was born on December 22nd 1887.
In 1900 he began to work on his own on mathematics summing geometric and
arithmetic series. During his high
school studies at Kumbakonam, Ramanujan came across a mathematics book by G S
Carr called ‘Synopsis of elementary results in pure mathematics’. This book,
with its very concise style, allowed Ramanujan to teach himself mathematics.
The book contained theorems, formulae and short proofs. It Contained
about 4865 formulas.
His Journey towards Mathematics
Professor
G.H.Hardy was his friend, philosopher
and guide. In 1940, Hardy gave two lectures at Yale University, which were
subsequently published as a book entitled: "Ramanujan: Twelve Lectures
inspired by his life and work". Earlier, in 1927, Hardy, along with Dewan
Bahadur Ramachandra Rao and P V Seshu Iyer, brought out the "Collected
papers of Srinivasa Ramanujan", which have been more recently reprinted,
in 1999, by the American Mathematical Society and the London Mathematical
Society. This reprinting of the two
volumes at the dawn of this century clearly is an indication of the intrinsic
worth of the work of Ramanujan in his brief life span of 32 years, 4 months and
4 days, of which he spent five years, 1914-919, at the Trinity College,
Cambridge University.
By 1904
Ramanujan had begun to undertake deep research. He investigated the series
∑(1/n) and calculated Euler's constant
to 15 decimal places. He began to study the Bernoulli numbers. In 1906
Ramanujan went to Madras where he entered Pachaiyappa's College. Continuing his mathematical work Ramanujan
studied continued fractions, hyper geometric series and divergent series.
Ramanujan
continued to develop his mathematical ideas and began to pose problems and
solve problems in the Journal of the Indian Mathematical Society. He devoloped
relations between elliptic modular equations in 1910. After publication of a
brilliant research paper on Bernoulli numbers in 1911 in the Journal of the
Indian Mathematical Society he gained recognition for his work. Despite his
lack of a university education, he was becoming well known in the Madras area
as a mathematical genius.
The man near to Infinity :
In 1914, Hardy brought
Ramanujan to Trinity College, Cambridge, to begin an extraordinary
collaboration. Right from the start
Ramanujan's collaboration with Hardy led to
important results.
On 16 March
1916, Ramanujan graduated from Cambridge
with a Bachelor of Science by Research (the degree was called a Ph.D. from
1920). Ramanujan's dissertation was on ‘Highly
composite numbers’ and consisted of seven of his papers published in England.
Ramanujan
fell seriously ill in 1917 and spent most of his time in various nursing
homes. On February 18, 1918, Ramanujan was elected a fellow of the
Cambridge Philosophical Society and then three days later, the greatest honour
that he would receive, his name appeared on the list for election as a fellow
of the Royal Society of London. On 10 October 1918 he was elected a Fellow
of Trinity College Cambridge, the fellowship to run for six years.
Gliding glimpses of Ramanujan;s Work :
The letters
Ramanujan wrote to Hardy in 1913
had contained many fascinating results. Ramanujan worked out the Riemann series,
the elliptic integrals, hypergeometric series and functional equations of the zeta function. Ramanujan independently discovered results
of Gauss, Kummer and others
on hypergeometric series. Ramanujan's own work on partial sums and products of
hypergeometric series have led to major development in the topic.
In a joint
paper with Hardy, Ramanujan
gave an asymptotic formula for p(n). Ramanujan left a number of unpublished
notebooks filled with theorems that mathematicians have continued to study. G N Watson, Mason
Professor of Pure Mathematics at Birmingham from 1918 to 1951 published 14
papers under the general title Theorems stated by Ramanujan and in all he
published nearly 30 papers which were inspired by Ramanujan's work. Hardy passed on
to Watson the large
number of manuscripts of Ramanujan that he had, both written before 1914 and
some written in Ramanujan's last year in India before his death.
Ramanujan's infinite Series
One of
Ramanujan's infinite series is now the basis for methods used to compute Pi:
Ramanujan's
equation arrives at values of Pi to large numbers of decimal places more
rapidly than just about any other known series. Each extra term in the summation
adds around eight digits to the decimal expantion of π. Ramanujan
calculated the value of π to 14 decimal places. i.e. 3.141592653589793.
Ramanujan
also gave 14 other series for 1/π but offers little explanation of where they
came from. Even now, with the help of a more theoretical understanding aided by
mathematical tools such as computer software for manipulating algebric
expressions, mathematicians still find it hard to generate the kind of
identities that Ramanujan already found.
Ramanujan and Euler's Constant
Ramanujan
was evidently fascinated with Euler’s Constant
In his
second note book, Ramanujan gave many beautiful formulas for π and 1/ π and
Euler's constant γ =
0:57721566 … , which occurs in many well-known formulas involving the Gamma
function, the Riemann zeta function, the divisor function d(n), etc.
From 1970
onwards Mathematicians discovered the importance of Ramanujan’s work
on gamma, Riemann Zeta functions
& Euler’s constant in the
application of Computer Science,
particularly, in the field of
security of internet, etc.,
Magic square
A magic
square is an arrangement of numbers (usually integers) in a square grid, where the numbers in each row, and in each column, and
the numbers that run diagonally in both directions, all add up to the same
number.
Magic
square of order 3
The constant that is the sum of every row,
column and diagonal is called the magic constant or magic
sum, M. Every normal magic square has a unique constant determined solely by
the value of n, which can be calculated using this formula:
For example, if n = 3, the formula says M = [3
(32 + 1)]/2, which simplifies to 15. For normal magic squares of order n = 3,
4, 5, 6, 7, and 8, the magic constants are, respectively: 15, 34, 65, 111, 175,
and 260.
A construction of a magic square of order 4 :
Go left to right through the square counting
and filling in on the diagonals only. Then continue by going left to right from
the top left of the table and fill in counting down from 16 to 1. as shown
below.
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An extension of the above example for Orders 8 and 12 First
generate a "truth" table, where a '1' indicates selecting from the
square where the numbers are written in order 1 to n2 (left-to-right, top-to-bottom),
and a '0' indicates selecting from the square where the numbers are written in
reverse order n2 to 1. For M = 4, the "truth" table is as shown
below, (third matrix from left.)
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Continued
Fraction
Let us take P / Q as general form of a continued fraction. Where P and Q are whole, positive
numbers. Then expressing in the form of
a continued fraction,
=a+1/(b+1)/(c+1/(d+…….))) =a+
Where a, b, c, d, e, etc are all whole
numbers. If P/Q is less than 1, then the
first number a, will be 0.
Ramanujan developed a number of interesting
closed-form expressions for non-simple continued fractions. These include the almost integers.
1)
2)
The Hardy-Ramanujan Number :
The following is a famous story
told by G.H. Hardy about S.Ramanujan.
Once, in a taxi from London,
Hardy noticed its number, 1729.
When Hardy met Ramanujan in a hospital, he declared ‘1729’ as a dull
number,. Immediately, Ramanujan answered, “No Hardy, it is a very interesting
number. It is the smallest number, expressible as the sum of two cubes in two
different ways.”
The number 1729 has since become known as Hardy-Ramanujan number, “the sum of two positive cubes in two
different ways”
Ramanujan published 39 papers in
all, of which 5 were in collaboration with Hardy. He also proposed 59 questions
and/or Answer to Questions in the JIMS, during his short life span of 32 years,
4 months and 4 days.
The
Mathematic genius achieved
infinite things during his short life span, Today, the world of Mathematics
remembers him, honours him and several Departments and Institutes have been named after him.
Saturday, 1 November 2014
Suggetions for IAS,IPS and other Civil Services Examinations.
* Aspirants must develop their lingual ability to do well in the CSAT and also in the Main examination and in the Personality test.*Aspirants must develop their numerical ability and problem solving skills to do well in CSAT.
Candidates must practice to solve many puzzles in Mathematics. By writing model tests in a simulated
environment, this skill can be developed.
* Aspirants must develop special reading habits. Extensive reading of multiple news papers and magazines is to be cultivated.
*Aspirants must take interest in general studies ¤t affairs right from school -college studies so that general knowledge is gained as a routine.
*Candidates must make complete and thorough coverage of syllabus, with additional stress on important topics.
*At the examination ,judicious allocation of time over the number of questions to be answered is a must.
*Candidates should not leave hope, even if the success does not turn up in the first one or two attempts.Experience gained from the earlier attempts can be used to one's advantage in the next attempt.
*Besides one should choose quality coaching institute.
*Engineering graduates in large number can come forward to take up the exam as their success rate is higher than that of other students.
*Candidates must capitalize on educational achievements of their family members.
*Hard work, methodical preparation ,perseverance, etc are needed. Above all, a great degree of commitment and achievement motivation is a pre- requisite for success in the Civil Services Examination.
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