what is a wormhole?

Wormholes are solutions to the Einstein field equations for gravity that act as "tunnels," connecting points in space-time in such a way that the trip between the points through the wormhole could take much less time than the trip through normal space.

The first wormhole-like solutions were found by studying the mathematical solution for black holes. There it was found that the solution lent itself to an extension whose geometric interpretation was that of two copies of the black hole geometry connected by a "throat" (known as an Einstein-Rosen bridge). The throat is a dynamical object attached to the two holes that pinches off extremely quickly into a narrow link between them.

This analysis forces one to consider situations...where there is a net flux of lines of force through what topologists would call a handle of the multiply-connected space and what physicists might perhaps be excused for more vividly terming a ‘wormhole’.

John Wheeler in Annals of Physics

Note to Visitors

The content viewed in this blog is a collection of various articles & newsletters and is placed only for educational purpose.

Monday, November 28, 2011

September 5th

September 5 is Teacher’s Day in “India”. It is the birthday of second President of India and teacher Dr. Sarvapalli Radhakrishnan. When Dr. Radhakrishnan became the president of India in 1962, some of hisstudents and friends approached him and requested him to allow them to celebrate 5 September, his birthday. In reply, Dr. Radhakrishnan said, “Instead of celebrating my birthday separately, it would be my proud privilege if September 5 is observed as “Teachers Day”.

This is not a holiday in India. It is considered a “celebration” day, where teachers and students report to school as usual but the usual activities and classes are replaced by activities of celebration, thanking and remembrance. At some schools on this day, the responsibility of teaching is taken up by the senior students as an appreciation for their teachers.

Traditionally,people in India have given tremendous respect and honor to teachers. An old Indian saying (usually taught to children), ranks teacher in the third place, even before God: “‘Maata, Pitha, Guru, Daivam’”, meaning Mother, Father and Teacher is God.

There is a difference between the spiritual teacher and a material teacher. For spiritual teacher, who causes to remove all the illusions from the mind of his disciple and makes him feel the precence of God, there is another saying in the form of a couplet (doha), which goes, “Guru Govind doou khare kake lagon paai? Balihari guru aap ki Govind deeo batai,” Meaning “I am in a fix whom to salute first: the teacher or the God. I shall choose the teacher as he is the one who is instrumental in me knowing the God”. Further, a central piece in Hindu scripture reads “Gurur Brahma, Gurur Vishnu, Guru devo Maheshwaraha - Gurussaakshaath param brahma tasmai shree gurave namaha,” which translates as “The Guru (Teacher) is the Lord Brahma (the Creator), the Guru is the Lord Vishnu (the Preserver), the Guru is the Lord Shiva (the Destroyer). The Guru is the Supreme Brahman (Ultimate Reality) visible to our eyes. To that Guru we offer our salutations”

There were always some confusions between a spiritual teacher to a material teacher. But these two are not at the same level and one must make sure that how to treat them individually.

Teacher’s Day Celebration

All across the world, Teacher’s Day celebrations are undertaken to commemorate the teachers for their efforts. By having celebrations on Teacher’s Day we convey the message that we care for our teachers. Celebrating Teachers Day is recognition of the devotion with which teachers undertake the responsibility of educating a child.

Teacher’s Day is one of the occasion on which teachers are praised. On this day, school students dress up like their teachers and attend classes acting like their teachers. As the day passes the students perform the activities that are performed by the teachers. Sometimes the teachers also sit in the classes acting like students, reliving the time when they, themselves, were students. This goes a long way towards creating an understanding between the teachers and their students.

Apart from being the day when we give recognition to our teacher’s hard work, this day enables a healthy interaction between students and teachers. However simple the celebrations may be, they reflect the fact that we care for our teachers. So, we should never forget to celebrate this special day for our teachers. There are many ways of celebrating Teacher’s Day. So, how to celebrate Teachers’ Day is to be decided by you.

Teacher’s Day

Teachers have an influencing role in the life of a student. They are like beacons of light guiding us in the formative years of our life. A teacher moulds us and in the process shapes our future. What we learn from our teachers remains with us throughout our life giving us direction. But very often, we fail to show our appreciation and gratitude for their devotion. Teachers do need encouragement and support from the community to feel that their efforts are being recognized. Towards this end only,

Teacher’s Day is celebrated throughout the world. By celebrating National Teacher’s Day we thank our teachers for providing us their invaluable guidance.

Monday, November 14, 2011

Theory and Research-based Principles of Learning

The following list presents the basic principles that underlie effective learning. These principles are distilled from research from a variety of disciplines. 

1. Students’ prior knowledge can help or hinder learning. 
  • Students come into our courses with knowledge, beliefs, and attitudes gained in other courses and through daily life. As students bring this knowledge to bear in our classrooms, it influences how they filter and interpret what they are learning. If students’ prior knowledge is robust and accurate and activated at the appropriate time, it provides a strong foundation for building new knowledge. However, when knowledge is inert, insufficient for the task, activated inappropriately, or inaccurate, it can interfere with or impede new learning. 

2. How students organize knowledge influences how they learn and apply what they know. 
  • Students naturally make connections between pieces of knowledge. When those connections form knowledge structures that are accurately and meaningfully organized, students are better able to retrieve and apply their knowledge effectively and efficiently. In contrast, when knowledge is connected in inaccurate or random ways, students can fail to retrieve or apply it appropriately. 

3. Students’ motivation determines, directs, and sustains what they do to learn. 
  • As students enter college and gain greater autonomy over what, when, and how they study and learn, motivation plays a critical role in guiding the direction, intensity, persistence, and quality of the learning behaviors in which they engage. When students find positive value in a learning goal or activity, expect to successfully achieve a desired learning outcome, and perceive support from their environment, they are likely to be strongly motivated to learn. 

4. To develop mastery, students must acquire component skills, practice integrating them, and know when to apply what they have learned. 
  • Students must develop not only the component skills and knowledge necessary to perform complex tasks, they must also practice combining and integrating them to develop greater fluency and automaticity. Finally, students must learn when and how to apply the skills and knowledge they learn. As instructors, it is important that we develop conscious awareness of these elements of mastery so as to help our students learn more effectively. 

5. Goal-directed practice coupled with targeted feedback enhances the quality of students’ learning. 
  • Learning and performance are best fostered when students engage in practice that focuses on a specific goal or criterion, targets an appropriate level of challenge, and is of sufficient quantity and frequency to meet the performance criteria. Practice must be coupled with feedback that explicitly communicates about some aspect(s) of students’ performance relative to specific target criteria, provides information to help students progress in meeting those criteria, and is given at a time and frequency that allows it to be useful. 

6. Students’ current level of development interacts with the social, emotional, and intellectual climate of the course to impact learning. 
  • Students are not only intellectual but also social and emotional beings, and they are still developing the full range of intellectual, social, and emotional skills. While we cannot control the developmental process, we can shape the intellectual, social, emotional, and physical aspects of classroom climate in developmentally appropriate ways. In fact, many studies have shown that the climate we create has implications for our students. A negative climate may impede learning and performance, but a positive climate can energize students’ learning.

7. To become self-directed learners, students must learn to monitor and adjust their approaches to learning. 
  • Learners may engage in a variety of metacognitive processes to monitor and control their learning—assessing the task at hand, evaluating their own strengths and weaknesses, planning their approach, applying and monitoring various strategies, and reflecting on the degree to which their current approach is working. Unfortunately, students tend not to engage in these processes naturally. When students develop the skills to engage these processes, they gain intellectual habits that not only improve their performance but also their effectiveness as learners.

Saturday, November 12, 2011

Black Hole


Every Black Hole Contains Another Universe? And our universe may sit in another universe's black hole, equations predict. Like part of a cosmic Russian doll, our universe may be nested inside a black hole that is itself part of a larger universe. In turn, all the black holes found so far in our universe—from the microscopic to the super-massive may be doorways into alternate realities.

According to a mind-bending new theory, a black hole is actually a tunnel between universes—a type of wormhole. The matter the black hole attracts doesn't collapse into a single point, as has been predicted, but rather gushes out a "white hole" at the other end of the black one, the theory goes. (Related: "New Proof Unknown 'Structures' Tug at Our Universe.")

In a recent paper published in the journal Physics Letters B, Indiana University physicist Nikodem Poplawski presents new mathematical models of the spiraling motion of matter falling into a black hole. His equations suggest such wormholes are viable alternatives to the "space-time singularities" that Albert Einstein predicted to be at the centers of black holes. According to Einstein's equations for general relativity, singularities are created whenever matter in a given region gets too dense, as would happen at the ultradense heart of a black hole. Einstein's theory suggests singularities take up no space, are infinitely dense, and are infinitely hot—a concept supported by numerous lines of indirect evidence but still so outlandish that many scientists find it hard to accept.

If Poplawski is correct, they may no longer have to. According to the new equations, the matter black holes absorb and seemingly destroy is actually expelled and becomes the building blocks for galaxies, stars, and planets in another reality. (Related: "Dark Energy's Demise? New Theory Doesn't Use the Force.")

Wormholes Solve Big Bang Mystery?

Collection of Books on Teaching Methods

Popular Posts