Dr. S. D. Manjarekar (Ph.D.), BoS in Mathematics and Statistics, S. P. P. U. , Pune

Wednesday, January 24, 2024

What is an Erdős number ?

 What is an Erdős number?

  • It's a measure of the "collaborative distance" between a mathematician and the prolific Hungarian mathematician Paul Erdős, based on co-authorship of publications.
  • It's a way to track the interconnectedness of mathematicians and their collaborative networks.

How is it calculated?

  1. Erdős himself has an Erdős number of 0.
  2. Anyone who co-authored a paper directly with Erdős has an Erdős number of 1.
  3. Anyone who co-authored a paper with someone who has an Erdős number of 1 has an Erdős number of 2, and so on.

Key points:

  • Lower Erdős numbers generally indicate a closer connection to the world of mathematics and a greater degree of collaboration.
  • The average Erdős number is around 5, but it can range up to 13.
  • Over 11,000 people have an Erdős number of 2.
  • Having a finite Erdős number is considered a badge of honor among mathematicians.

Interesting facts:

  • Albert Einstein has an Erdős number of 2.
  • The actor Kevin Bacon has an Erdős–Bacon number of 6 (combining Erdős number and Bacon number, a similar concept for film collaborations).
  • There are databases and websites dedicated to tracking Erdős numbers, such as the Erdős Number Project at Oakland University.

Beyond mathematics:

  • The concept of Erdős numbers has been applied to other fields where collaboration is common, such as physics, chemistry, and computer science.
  • It's a fascinating way to visualize and study the interconnectedness of researchers and the spread of ideas within a field.
Where I can find my Erdős Number ?

                 Go to the webpage 

https://mathscinet.ams.org/mathscinet/freetools/collab-dist 

The only person with Erdos #0 is Erdos himself. Denote E0={Erdos}.

The set of persons with Erdos #1 is the set of those persons who have at least one published paper with Erdos. Call this set E1.

The set of persons with Erdos #2 is the set of those persons who do not belong to E1 and have at least one published paper with someone in E1. Call this set E2.

The set of persons with Erdos #3 is the set of those persons who do not belong to E1E2 and have at least one published paper with someone in E2. Call this set E3.

In general, you have Erdos # if you do not belong to E1E2E1 and have at least one published paper with someone in E1. Call this set E.


My Erdős Number is 6.



Artificial Bee Colony (ABC) algorithm

           The Artificial Bee Colony (ABC) algorithm is a swarm intelligence optimization algorithm inspired by the foraging behavior of honey bees. It was first proposed by Dervis Karaboga in 2005 and has since become a popular and effective tool for solving a wide range of optimization problems.

Here's a breakdown of the ABC algorithm:

Structure:

  • Bees: The bees in the ABC algorithm represent potential solutions to the optimization problem. Each bee is associated with a food source, which represents a candidate solution.
  • Types of bees: There are three types of bees in the ABC algorithm:
    • Employed bees: These bees are responsible for exploiting the food sources that they have discovered. They do this by modifying the positions of their associated food sources and evaluating the quality of the new solutions.
    • Onlooker bees: These bees watch the dances of the employed bees and choose food sources based on the information they gather. They may choose to exploit the food source of a successful employed bee or explore new areas of the search space.
    • Scout bees: These bees are responsible for exploring new areas of the search space and discovering new food sources. They do this by randomly generating new solutions.

Process:

  1. Initialization: The ABC algorithm starts by randomly initializing a population of food sources.
  2. Employed bee phase: Each employed bee modifies the position of its associated food source and evaluates the quality of the new solution. If the new solution is better than the old one, the bee replaces the old solution with the new one.
  3. Onlooker bee phase: The onlooker bees watch the dances of the employed bees and choose food sources based on the information they gather. They may choose to exploit the food source of a successful employed bee or explore new areas of the search space.
  4. Scout bee phase: If a food source has not been improved for a certain number of iterations, it is abandoned by its employed bee. A scout bee then replaces the abandoned food source with a new one that is randomly generated.
  5. Termination: The ABC algorithm terminates when a stopping criterion is met, such as a maximum number of iterations or a desired level of fitness is reached.

Benefits:

  • Simple and easy to implement: The ABC algorithm is relatively simple to implement compared to other optimization algorithms.
  • Effective for a wide range of problems: The ABC algorithm has been successfully applied to a wide range of optimization problems, including continuous, discrete, and mixed-integer problems.
  • Robust to noise: The ABC algorithm is robust to noise in the data and can find good solutions even when the data is not perfect.

Applications:

The ABC algorithm has been used to solve a wide range of problems, including:

  • Scheduling problems
  • Resource allocation problems
  • Engineering design problems
  • Machine learning problems
  • Data mining problems

Visualization:

Here's an image depicting the process of the ABC algorithm:

Image of Artificial Bee Colony Algorithm process

Role of Mathematics in NEP - 2020

               The National Education Policy 2020 (NEP 2020) places a significant emphasis on mathematics, recognizing its crucial role in developing crucial skills and fostering a vibrant knowledge-based society. Here's a breakdown of its role:

1] Foundational Literacy and Numeracy (FLN):

       NEP 2020 prioritizes strong FLN skills as the building blocks for all future learning. Early childhood care and education programs focus on developing basic numeracy skills like counting, addition, and subtraction. This strong foundation helps students grasp complex concepts later in their education.

2] Holistic and Integrated Approach:

     NEP 2020 promotes a shift from rote memorization to understanding and applying mathematical concepts. It encourages using real-life contexts and interdisciplinary connections to make learning more engaging and relevant. Students connect mathematics to other subjects like science, economics, and even art, fostering a holistic understanding.

3] Flexibility and Choice:

    NEP 2020 introduces a flexible credit-based system, allowing students to choose additional mathematics courses aligned with their interests and aptitudes. This caters to diverse learning styles and prepares students for various career paths.

4] Emphasis on Critical Thinking and Problem-Solving:

   NEP 2020 goes beyond calculations and formulas, focusing on developing critical thinking, reasoning, and problem-solving skills. Students learn to analyze situations, formulate solutions, and make informed decisions, essential skills for navigating the complexities of the 21st century.

5] Technology Integration:

  NEP 2020 encourages the use of technology in mathematics education, including coding and computational thinking. This helps students develop digital literacy skills and prepares them for future technological advancements.

6] Teacher Training and Support:

     NEP 2020 recognizes the importance of well-trained and motivated teachers for effective mathematics education. It emphasizes continuous professional development programs for teachers and innovative teaching methodologies.


         Overall, NEP 2020 envisions a mathematics education system that: Equips students with strong foundational skills and critical thinking abilities. Makes learning engaging and relevant to real-life situations. Provides flexibility and choice to cater to diverse needs. Prepares students for success in various fields and empowers them to be productive citizens in a knowledge-driven world. Remember, NEP 2020 is still in its early stages of implementation, and its impact on the role of mathematics in education will unfold over time. However, its focus on a holistic, flexible, and application-oriented approach holds immense promise for transforming mathematics education in India.


Sunday, January 14, 2024

Albert Einstein and Subrahmanyan Chandrasekhar

      The relationship between Albert Einstein and Subrahmanyan Chandrasekhar was complex and nuanced, encompassing elements of both collaboration and disagreement. While it wouldn't be entirely accurate to label it a simple "rivalry," it is true that there were periods of tension and differing viewpoints around Chandrasekhar's work on stellar evolution, particularly regarding the fate of massive stars.

Here's a breakdown of their relationship:


A) Early support and collaboration:


             Einstein initially recognized Chandrasekhar's talent and supported his early career. He helped him secure a fellowship at Cambridge University and even nominated him for the Nobel Prize in 1936.They collaborated on a paper in 1939 on the radiation of stars.

B) Friction and disagreement:

         Chandrasekhar's 1935 paper proposed the Chandrasekhar limit, which states that a white dwarf exceeding 1.44 solar masses would collapse under its own gravity. This contradicted Einstein's belief that white dwarfs could reach any mass.Einstein strongly opposed the Chandrasekhar limit, even publicly criticizing it for several years. This period of disagreement created some tension between them.

C) Reconciliation and mutual respect:

         Despite their differences, Einstein eventually acknowledged the validity of Chandrasekhar's work. He publicly admitted his mistake in 1966, citing new observational evidence.While their collaboration didn't resume, they maintained a level of mutual respect and admiration for each other's work.


Overall:

     While there were periods of disagreement and tension, it's important to avoid framing their relationship as solely a "rivalry." Their interactions were more complex, encompassing both support and criticism.Ultimately, their contrasting viewpoints led to further exploration and understanding of stellar evolution. Chandrasekhar's work, later confirmed by observation, paved the way for our current understanding of supernovae and black holes.


Here are some additional points to consider:

      Other scientists like Arthur Eddington also played a role in the debate surrounding the Chandrasekhar limit.

       The nature of scientific progress often involves disagreement and challenge. This can be a healthy process that leads to more robust understanding.


Saturday, January 13, 2024

What is Gödel numbering?

           It's a technique that assigns unique natural numbers (Gödel numbers) to symbols, formulas, and proofs within a formal language, like arithmetic or logic.

This makes it possible to represent mathematical statements and arguments as numbers, enabling their manipulation within arithmetic itself.

               Key steps involved:


1) Assigning numbers to symbols:

Each symbol in the formal language is assigned a unique prime number.

For example, 2 might represent "0", 3 might represent "=", 5 might represent "(", etc. Gödel numbering symbols


2) Gödel numbering symbols

Encoding sequences of symbols as numbers:

        To represent a sequence of symbols (like a formula), Gödel numbers are combined using exponentiation.

        Each symbol's prime number is raised to a power corresponding to its position in the sequence.

         The resulting powers are then multiplied together to create a unique Gödel number for the entire sequence. 

3) Gödel numbering formula example

Example:

The formula "0 = 0" would be encoded as:

Gödel number for "0": 2

Gödel number for "=": 3

Gödel number for "0": 2

Combining using exponentiation and multiplication: 2^1 * 3^2 * 2^3 = 2430


4) Significance:

       Encoding of mathematics within mathematics: Gödel numbering allows statements about mathematics to be expressed as mathematical statements themselves.

      Proving incompleteness theorems: Gödel used this technique to prove his famous incompleteness theorems, which demonstrate fundamental limitations of formal systems.

5) Other applications: 

         Gödel numbering has applications in computability theory, recursion theory, and other areas of logic and mathematics.

Key takeaways:

Gödel numbering provides a way to bridge mathematics and numbers.

It was crucial for proving fundamental limits of formal systems.

Its impact extends beyond logic into computer science and mathematics.

Contribution of Varāhamihira to Indian Knowledge System in Mathematics and Astronomy

                      Varāhamihira was an influential Indian scholar who made significant contributions to the fields of mathematics and ast...