4-2023 What is ISBN ? How does it work ?

Have you ever noticed on the back cover of every book is a barcoded pattern with some numbers ? Ever wondered what could that possibly mean ? According to wikipedia "The International Standard Book Number (ISBN) is a numeric commercial book identifier that is intended to be unique. Publishers purchase or receive ISBNs from an affiliate of the International ISBN Agency. " It helps librarians and bookstores keep track of books in their custody. The bar code replaces the ISBN for automated inventory control.

The ISBN is structured as in the digram given on the right:

Recently, my new book on Ramanujan got an ISBN: 978-1-5457-5712-3 (shown in the image below).

Also see:: How do barcodes work in the book publishing industry ?

2-2021 This may happen to you, if you are a mathematician taking a flight !

Why should mathematicians avoid flying ?

This may happen to you too .....

Flight attendant: Is there a doctor on board?
Me: Yes, but I'm not that kind of…
Flight attendant: The pilots are arguing about whether there are as many irrational numbers as rational numbers.
Me: Okay. I’m here.

(Based on a Tweet by @LongFormMath, Jay Cummings, 2021-09-28)

2-2018 Teaching by misleading

A good teacher never misleads his/her students. Right ? Wrong ?

As a teacher, I often ask questions in the class, basically to nudge and provoke my students to think. Sometime these questions have a misleading hint, just to confuse the student and lead him/her to the right concept. My favourite one is in my class on "number theory" when I wave my palm with all fingers open, and ask the question "show me the number five". The students invariably fall for the visual cue (my open palm) and fumble around, till I emphasise that a number is only an abstraction and cannot be used/shown all alone. I feel that such (misleading) prompting questions can often be useful in the classroom. But, this should be done in moderation and very carefully.

What does this community think about my approach ? Send me a mail.

1-2017 More on the randomness of randomness.

Some time ago, I published this short article on randomness. I thought I was the only one who had such silly doubts on uch a well-known mathematical concept. And, now, I discover the profoundness of my question. I found this interesting article, on stackexchange. Thanks to the guys who posted the article and the responses. I love the opportunity to learn.

45 / 2012 FOSS for mathematics

I have added a detailed report on FOSS tools for those who use mathematics.

The report is downloadable from ::
http://www.freewebs.com/profpartha/publications/fossmath5.pdf

partha

1 / 2012 Happy New Year -- commemorating a historical blunder

Why is the circle divided into 360 degrees ?

What is the logic of choosing a weird number 360 to divide a circle ? Why not choose something more manageable, like 10, 100 or 1000 ?

Early mathematicians who invented the science of "geometry" decided to divide a circle into 360 degrees. But why ? Why 360 ?

There, goes a story many of us have not heard of, or have forgotten. The word geometry itself is inspired from geo -- earth, metry-- measurements (just like the geo in geo-graphy, or geo-logy). We have just started a New Year according to our common Gregorian calendar. They say, we saw the earth going around the sun in some 360 days (according to their crude and primitive measurements). The earth just completed going around the sun once. In fact, we have just seen 366 (or 365) sunrises, since the last new Year's Day. This was the begining of the blunder we imposed on ourselves.

Although, later this was proved wrong, we continue to stick to the 360 degrees rule of circles (each degree reminds us of one day in earth's annual excursion), a big blunder which the world has accepted since ages. So, every time we celebrate New Year, we must think of this historic blunder which we made several centuries ago.

Subsequent generations of mathematicians, corrected all this, giving rise to a bewildering variety of calendars. A good collection of calendar related information can be found at ::: http://www.hermetic.ch/cal_stud.htm

The science of geometry grew into the science of astronomy (now we start looking at the stars). We have now come to the stage when we can actually hope to visit these celestial bodies or even inhabit them.

Is'nt it incredible that all this started the faulty premise of 360 degrees to a circle ?

PS: In fact, mathematicians have a much more logical and intuitive, although clumsier way to divide a circle .

As usual, maths saves you from suffering the blunder.

partha

No nonsense intro to group theory

The intriguing concept of group theory is a nightmare for many learners (and teachers) of mathematics. Here is a no-nonsense way to approach this subject ::

http://dogschool.tripod.com/

Discover and enjoy !

partha

Well said...Prof. Einstein

(About mathematics) :: Why does this magnificent applied science, which saves work
and makes life easier, bring us so little happiness? The simple
answer runs: Because we have not yet learned to make sensible
use of it.
Albert Einstein

Why you should not be a maths Professor

Why you should not be a maths Professor ::

http://www.freewebs.com/profpartha/mathprof.htm

partha

Maths is no fun.... who says ?

Read these .....
http://blog.tanyakhovanova.com/?cat=9 (this one was written by a mathematician)


http://www.math.ualberta.ca/~runde/jokes.html (this one was written by a maths Prof)

....and now ask yourself the same question again.

partha

The Hardest Logic Puzzle Ever

The Hardest Logic Puzzle Ever -- by Raymond Smullyan

I have just received a book on logic puzzles, by Raymond Smullyan. Smullyan would be best described as the craziest and most gifted person in this world. He is a mathematician, a concert pianist, logician, writer, magician, conjurer, raconteur, all packed in one. Here is a masterpiece which I found on the Internet :

In 1992, George Boolos called the following "the hardest logic puzzle ever". I figured that people here would especially like it. It's certainly a Raymond Smullyan inspired puzzle and goes as follows.

"Three gods A, B, and C are called, in some order, True, False, and Random. True always speaks truly, False always speaks falsely, but whether Random speaks truly or falsely is a completely random matter. Your task is to determine the identities of A, B, and C by asking three yes-no questions; each question must be put to exactly one god. The gods understand English, but will answer all questions in their own language, in which the words for yes and no are 'da' and 'ja', in some order. You do not know which word means which."

Just for the sake of clarity, George Boolos gives the following four clarifications: (1) It could be that one god gets asked more than one question (and thus, some god is not asked any question at all). (2) What the second question is, and to which god it is put, may depend on the answer to the first question (likewise, for the third question). (3) Whether Random speaks truly or not should be thought of as depending on the flip of a coin hidden in his brain: if the coin comes down heads, he speaks truly; if tails, falsely. (4) Random will answer 'da' or 'ja' when asked any yes-no question.

Good luck!

partha

PS: The person who solves the above puzzle will be declared as the "second Smullyan", in this blog. You can email me your ssolutions.

PPS : To know more about Raymond Smullyan, visit ::
http://en.wikipedia.org/wiki/Raymond_Smullyan

PPPS: A solution is here.

PPPPS: This problem is described here

Problem solving books in mathematics

A good compilation of maths books is at :
http://ansomniac.blogspot.com/

This compilation was made by the same student from IIT Kharagpur, who was so very upset by the quality of his teachers (see my blog post "Lament of a student". Instead of brushing him aside as a "grumbler", I am happy that I decided to listen (that is what teachers should be doing).

I am sure this list should be useful for many of my colleague teachers.

partha

Lament of a student

I received this mail recently from a student of maths. If this is what a student feels, we teachers have a lot to think about.


partha



QUOTE //**
Dear Sir,

I am third year undergraduate student at Dept of Mathematics, IIT KGP. And the first thing I would like to say is that the Department Sucks!
I apologize for the language but this is the best I can do considering the enormous amount of frustration I have right now.

I love maths (mainly pure maths) and I am pretty good at it, well at least good enough to understand and appreciate the beauty and depth of this subject. I was up all night going through the awesome library of math books that I have created at my room, solving some olympiad problems and now I'll sleep till the evening missing all my lectures. Is it the right thing to do? Well if the "professors" who teach us maths have no love for the subject or teaching then I think that it is. And I even have real doubts about the competence of some profs as well. Ask them a problem and they'll fumble and they'll ask for some time till the next class and even then it seems like they just mugged up a solution.

It's pathetic! I want to complain, I want to shout at the administration, at the profs, abuse them! But I can't, because I fear they'll ruin my only chance of escape - going for a PhD in maths at a better place, a place where the people teach because they love teaching and because they are good at it.

I am sorry for bothering you with this mail, but after reading your article I felt that you are one of those people who can understand my frustration and I felt like venting.

**// UNQUOTE

The article which provoked the above mail was here originally ::

http://www.freewebs.com/profpartha/publications/futile.pdf

The above article is now at ::

https://drpartha.org.in/publications/futile.pdf

***

Abel Prize 2011

The Norwegian Academy of Science and Letters has decided to award the Abel Prize for 2011 to John Milnor, Institute for Mathematical Sciences, Stony Brook University, New York “for pioneering discoveries in topology, geometry and algebra”. Professor Milnor has received all the major awards in Mathematics: He was awarded the Fields Medal in 1962, the Wolf Prize in 1989 and is the only person to have won all the three Steele Prizes of the American Mathematical Society (AMS) in 1982, 2004 and early this year for seminal contribution to research, for mathematical exposition and for lifetime achievement respectively. He also received the U.S. National Medal of Science in 1967.

Prof Milnor's biography is at
http://www.abelprisen.no/en/prisvinnere/2011/.

Niels Henrik Abel (1802-1829) was a brilliant Norwegian mathematician who accomplished an amazing amount of brilliant work in his short lifetime. Abel died of tuberculosis at the age of 26 after being forced to live in miserable conditions because of his inability to obtain a university post. The offer of a professorship in Berlin was not forthcoming for four years, by which time it was too late. The letter arrived two days after Abel's death, informing him that he had been offered professorship at the University of Berlin.

For lovers of mathematics

Lovers of mathematics will

love this.

Take a look.

partha

I now have an entry in the Electronic World Directory of Mathematicians (EWDM) maintained by the International mathematical Union.

Visit ::

http://www.mathunion.org/ewdm/search.php

and search for "partha"


partha

Intl. Math. Union (IMU) Newsletter

IMU recently conducted the ICM2010 Conference in Hyderabad. Unfortunately, teachers like me, do not have the money to pay for the registration expenses. But there is some hope for us. We can keep ourselves informed, by subscribing to the FREE (gratis) newsletter of IMU:: IMU-Net.

There are two ways of subscribing to IMU-Net:

1. Click on http://www.mathunion.org/IMU-Net with a Web browser and go
to the "Subscribe" button to subscribe to IMU-Net online.

2. Send an e-mail to imu-net-request@mathunion.org with the Subject-line:
Subject: subscribe

In both cases you will get an e-mail to confirm your subscription so
that misuse will be minimized. IMU will not use the list of IMU-Net
addresses for any purpose other than sending IMU-Net, and will not
make it available to others.

Previous issues can be seen at:
http://www.mathunion.org/imu-net/archive/


The IMU General Assembly, at its
meeting in Bangalore, prior to the ICM, decided that Seoul, the
capital of the Republic of Korea, will host the ICM in 2014. This
congress will take place from August 13 to 21, 2014.

partha

Mathematical writing

"Mathematical Writing" by Donald E. Knuth, Tracy Larrabee, and Paul M. Roberts

This is a report based on a course given at Stanford University in 1987.

I stumbled on a pdf version of this classic by D E Knuth. Gives you many rules of clean and clear mathematical writing. It borrows many ideas from the classic book of style by Struk and White. This is a must-read for all those who (like me) use maths for making a living. Wish my maths teachers had read this book before teaching me maths.

partha

**************