Subject: Invitation of Kerry Pendergast to the Film
Date: Mon, 21 Jul 2008 03:03:36 EDT
If at all possible I suggest that Kerry Pendergast be invited to contribute to the film. He has an outstanding ability to put facts over in a way that will interest ordinary people, and is also very accurate in detail as this sample shows. He is a member of the Court of the University of Aberystwyth, its superme governing body, and has already contributed to such programmes as “The Sky at Night”, hosted by Sir Patrick Moore, FRS. This is the longest running TV series in the world. His work has also been fetaured in “The Times Educational Supplement” and he is the science master at West Monmouth School in Pontypool. His teaching skills come over clearly in his virtual best seller “Crystal Spheres” (_www.aias.us_ (http://www.aias.us) ).
Pleaase find below the latest page of the Moon as aCrystal Sphere.      The story of general relativity starts with Euclid and his Euclidian geometry dealing with flat surfaces, because general relativity allows us to understand the force of gravity in terms of the geometry.  Euclid gave us the means to draw lines and angles and relate them together by theorems which explained how they interacted and depended on one another. Euclid gave us the means to mathematically construct a box and Einstein was able to make his breakthrough in general relativity by considering how an observer inside a box would perceive the actions of acceleration and gravity.  This thought experiment led Einstein to formulate his equivalence principle in which hemade the important step of realizing that the acceleration due to gravity has something to do with geometry – the equivalence principle.  The development of general relativity from the equivalence principle to the famous Einstein-Hilbert Equation field equation of general relativity required Einstein to become acquainted with developments in mathematics describing how objects move in time and space.      Vectors came into use at the turn of the eighteenth century and the term is derived from the Latin verb to carry. The vector points in the specified direction with its length giving the magnitude of the force required to ‘carry’ in that direction. It was first used by astronomers to describe how the ‘radius vector’, a line drawn from a planet to the focus of an ellipse, ‘carries’ the planet around the centre. Vector usually appeared in the phrase radius vector. The French term was rayon vecteur as seen in Laplace’s ‘Celestial Mechanics, which was translated by the British Civil List Scientist, astronomer and mathematician Mary Fairfax-Somerville1780-1872.      The modern meanings of the terms ‘vector’ and ‘scalar’ were introduced by William Rowan Hamilton (1805-1865) of Trinity College Dublin, in his paper to the Royal Irish Academy in 1844 entitled ‘On Quaternions’. Quaternions are a non-commutative extension of complex numbers which still find use in three dimensional rotations, but have largely been replaced by vectors.  Hamilton also introduced the term ‘tensor’ in 1846.      In 1906 when Einstein when started thinking about general relativity he turned to his old classmate Marcel Grossmann from his days in Zurich’s ETH University for advice on how to proceed. Grossmann was a mathematical genius and was able to acquaint Einstein with the work of Riemann, Christoffel, Ricci and Levi Civita on a then new kind of geometry, generally known as Riemann geometry, in which space and time were merged together in spacetime, and in which the framework or frame of reference could be dynamic and curve. Bianchi’s work was also to be of seminal importance in Einstein’s quest to extend special relativity to include the effects of acceleration and gravity.      Professor Luigi Bianchi(1856-1928) was a great Italian mathematician who worked in Pisa with Gregorio Ricci-Curbastro (1853-1925) who invented tensor calculus and Tullio Levi-Civita (1873-1941) who was born in and worked from Padua. All three mathematicians developed ground breaking mathematical treatments which were needed for the geometrically based Einstein-Hilbert Equation of general relativity.      In 1900 ‘Ricci’ and Levi-Civita published their theory of tensors which Einstein studied to help him understand the spherical geometry need for general relativity. In 1915 Levi-Civita corresponded with Einstein to correct some errors in his calculus and also contributed work to Paul Dirac’s equations in 1933.  Levi-Civita became a professor in Rome in 1918 where he worked successfully until he was sacked by the Fascist government.      Einstein’s breakthrough to general relativity and curved space started in 1907 when he realized that the effect of gravity and acceleration are the same thing. This is his equivalence principle. This can be shown by considering a box that could be isolated in space or a lift suspended by a cable in Earth’s gravity. A person in the box who could feel the effect of gravity would not be able to tell if he was stationary in a lift or being accelerated by a rocket in space. Similarly if the person felt was weightless, he would not know if he was isolated in space or the lift was in free fall. This is Einstein’s equivalence principle. Kerry7
