a weird coincidence !

This photo from NS tells most of the story:

The effects of gravitational fields are indistinguishable from the effects of accelerated motion. Read the whole story here

The 15-puzzle of Sam Loyd

The 15-puzzleis a sliding puzzle that consists of a frame of numbered square tiles in random order with one tile missing. Starting from the initial position of pic.1 we apply a finite number of planar reordering in such way that the bottom right square is not filled.

Every such reordering is a permutation of {1,2,…,15} , which is an element of . So the set G of all the permutations is a group of order 15.

The reordering is done by the means of the altering permutations like pic.2

Which are all the possible re orderings ? The answer is that G is equal to the group of even permutations. So

1 year zeracuse yeahhh…!!!

This gallery contains 6 photos.

 

 

 

~ grid generation is art … mesh around a klein bottle from Pointwise V17.1 R3 (for application notes look at the link).

Helen Arney showreel

Leonard Euler (15 April 1707)

306 years after Euler’s birth. Google made a mistake and wrote 360 and it’s spreading everywhere 😛 .

hobotopia again

these days sleep is a real value for everyone and for me even more 🙂

pay a visit  here

Hyde Park London (just for afrodite :P)

Largest Prime List Update …

New 17-million-digit monster is largest known prime  !!!

 is now the largest known prime number .The new prime, which has over 17 million digits, is only the 48th Mersenne prime ever found and the 14th discovered by GIMPS (Great Internet Mersenne Prime Search). Good news for cryptography …

nice one from here .Even if you don t like geometry problems , you should give it a try 🙂

PROBLEM :

What is the largest number of regions   that a plane is divided into by  straight lines in the plane?
Give  as a function of  and explain why your answer is correct.