Newton's Principia for the Common Reader (Physics)

Brilliantly Written! Professor Chandrasekhar simplifies Sir Isaac Newton’s monumental work and brings about great many aspects not obvious to most readers. It is the most famous scientific book ever written and the most difficult one also. Just fabulous! He was so greatly inspired to write on it, by the greatest human genius who ever lived! Kaiser T.

To appreciate this book, or even to understand it, you need to have graduate level physics. If you can meet this requirement you are in for a treat. Newton wrote his masterwork in Latin and used geometrical mathematics instead of calculus to derive his proofs, so this book owes its existence to some expert translators from Latin to English and then from Newtons obscure mathematics to modern methods. Prof Chandreshekar has done an outstanding job of presenting each part of Newtons work using modern calculus and then showing Newton s original and explaining how he derived his proofs. Using this approach he helps the reader to really see that Newton was a towering genius.

Even though the stated condition of the book was mostly correct, there was 1 marginal comment added in pen by the previous owner on page 41 where Newton's 1st and 2nd laws are mentioned. But this did not distract from the beautiful condition that this book was kept in. I am still completely satisfied with this purchase.

This book, which is Chandrasekhar's take on Newton's Principia (arguably the greatest scientific book ever written) is on a league of its own. Though it is an impressive work of scholarship, it is far from a mere retelling of Newton's great book. Chandrasekhar rederives in meticulous detail several of Newton's theorems and prodigiously restates the great man's theories using modern physics concepts and modern mathematical notation. Every serious physics student should read it (or at least read part of it, since the reading is far from easy going).

Properly printed

Very good.

Having browsed through this text over the years at a local college library, I finally broke down and bought this inexpensive paperback edition on Amazon. Realize this is not the complete Principia but Chandrasekhar has chosen to present and explain those parts which lead to the development of the theory of universal gravitation and its applications, e.g., lunar theory. This is not abridged, it's just what he selected. In addition to this at the end he adds four miscellaneous chapters which deal with variational type problems without Euler-Lagrange and even waves. In particular Newton's solution of the brachistochrone problem is presented and you see the idea of the small variation from the supposed true motion-all the ingredients which later lead to the Euler-Lagrange method are there though presented geometrically-a bit ahead of his time. Other reviews lead you to believe that a mastery of Euclid's Elements is needed to understand this text and/or the Principia. Actually if you remember the circle theorems for instance the measure of an angle inscribed in a circle is one-half the measure of its intercepted arc (arc measure is that of its central angle) and those ideas which lead to its proof as well as similarity and similar triangles and area of similar figures goes as the square of the proportionality constant and you can make sense out of what I just mentioned you're probably set. Newton does not simultaneously reproduce Euclid through his work or call upon Euclid's propositions by number but the ideas mentioned pervade a great deal of this work. Newton's more difficult constructions to be found in Principia were unknown to Euclid and many of these are not in Chandrasekhar's selections but they are built from these basic ideas. Newton discovered his calculus within the context of the analytic geometry of Descartes and there is little doubt that his mechanics was originally formulated in this framework also. Maybe Newton wanted to learn Euclid afresh for himself, maybe he believed the ancient Greek geometers had superior knowledge, though we now know he surpassed them considerably but his marriage of the calculus with Euclidean geometry extended its range considerably and was a prelude to differential geometry if not its most basic form. I'd like to give you a sample of Newton's creation where there is an interplay of geometry ideas and his calculus. For this I've chosen the first of Newton's "Superb" theorems which is in section 76 of chapter 15 in the Chandrasekhar text. If you imagine a particle placed anywhere within the interior space of a very thin spherical shell it will experience no net gravitational force from the shell or its mass. Draw a chord through the particle point which intersects the shell at two points on the inner side of the shell (inner and outer effectively coincide since thin). Draw another line through the particle point which makes a small angle dw with the chord-the line is assumed to cut outside the sphere in both of its directions. Now imagine this chord/line construct to be rigid and spin it about the chord as axis. It sweeps out a cone or if you like, two cones with the particle as apex. These cones obviously form identical solid angles (vertical angles are equal). If we assume the particle is not equidistant with the ends of the chord, we consider spheres with the particle as center and these two chordal distances for the lengths of the radii and we only consider the parts of the spheres which contain the solid angles or cones,i.e., the shorter cone is part of the smaller sphere and similar holds for the taller. These area caps at the ends of the cones partly extend outside the original sphere or shell. Next consider the original caps that we first cut from the shell when we spun about the chord. Draw radii from the shell center to the chordal endpoints. Note also the two radii just drawn and the chord form an isosceles triangle with base angles equal to the angle between the normal to the sphere at the chordal point and the extended chord line at each end. Now we apply a limiting procedure and we consider just one side as the other follows the same. Since we assumed at least within context that the chord is not a diameter the original cut cap is somewhat oblong with the shorter part coinciding with the cut circle diameter. Though we replaced the cut circle with a circular cap of different curvature due to sphere radius, as dw gets smaller they begin to coincide and go flat near zero. As the oblong original cap shrinks with dw it flattens forming an incline with the cone-an ellipse with minor axis the diameter of the cut circle. A bit of calculus to find ellipse area shows that the ratio of the ellipse area to the cut circle area is the major axis divided by the circle diameter and this forms a right triangle as dw approaches zero. Note the normal to the shell at the chordal point is perpendicular to the major axis (ellipse) and the normal to the circular cap is in line with the chord and also perpendicular to the circle diameter, i.e., the angle between the major axis and circle diameter is the same as a base angle of the isosceles triangle recently noted. Equivalently the ratio of the area of the spherical circular cap having chord end as vertex to the area of the portion of the spherical shell intercepted by the same cone is the cosine of the aforementioned base angle. This will be seen as needed to justify the last formula in the proof. If you get the book you'll understand the need for this monster-pardon my awkward prose. The idea is the spherical area parts originally cut by spinning about the chord each have area or mass proportional to the square of their respective distances from the particle as the areas become small or cone is thin but force goes as the inverse square so the force cancels for every chord-force goes as mass divided by inverse square. Those original parts were oblong and we found area to be the circular cap area divided by that base angle cosine as the cone thinned. The circular cap areas go as the squares of those aforementioned respective distances. So all the R's cancel and the cosines do too -base angles of an isosceles triangle. G-G=0. In truth it's easier by integrals- see Wikipedia or Vol. 1 of the Feynman Lectures. Later in the chapter Chandrasekhar notes that Newton used the method of images in a gravitational context and this was done 150 years before the credited discovery of Kelvin-Surprise Newton was first. No one noticed till Chandra did his study. In truth most physicists and engineers get predigested Newton or Newton lite and there's probably more that may be undiscovered here. That little blurb that I did above-Newton leaves it to the reader to complete the steps as did Chandrasekhar. You may yet profit from Newton and his biggest fan Chandrasekhar.

El producto llegó a tiempo, con Amazon no tengo queja. El problema es que no te dejan ver páginas internas en la vista previa y resulta que hay partes subrayadas por el autor que se ven bastante feas. Por otro lado, me pareció sorprendente la baja calidad del papel y la impresión del encuadernado, no sugiere que sea vendido por la Oxford Press Ed. Buscando el PDF en internet aparece de la misma manera, así que parece que el texto viene así de origen.

so hat sich auch Chandra für die Geschichte seiner Wissenschaft (und das ist die Physik) interessiert. Seine Bücher sind in der Regel nur mit Bleistift und Papier und viel Arbeit zu verstehen (so auch dieses!) aber wie immer lohnt sich der Aufwand! Man kaufe die Principia in der Bearbeitung von Cohen und Whitman The Principia: Mathematical Principles of Natural Philosophy und nehme Chandras Buch zur Interpretation mit dazu. Ein paar Monate harte Arbeit, und schon wird Newtons Principia zugänglich! Großartig!

Libro consegnato nei tempi previsti e in stato perfetto.

Not for the faint-hearted "general reader" (for whom it is said to be written). Even so a seamless exposition of Newton's mathematics in every area presented with clarity. Attractive diagrams too. You will need a very good command of mathematics to make the most of it.