To save content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about saving content to .
To save content items to your Kindle, first ensure no-reply@cambridge.org
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about saving to your Kindle.
Note you can select to save to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be saved to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
It is most useful that the true origins of memorable inventions be known, especially of those which were conceived not by accident but by an effort of meditation … One of the noblest inventions of our time has been a new kind of mathematical analysis, known as the differential calculus.
Gottfried Wiihelm von Leibniz. Historia et Origo Calculi Differentialis (1714)
THE DEVELOPMENT OF DIFFERENTIAL CALCULUS
After the advent of algebra in the sixteenth century, mathematical discoveries inundated Europe. The most important were differential calculus and integral calculus, bold new methods for attacking a host of problems that had challenged the world's best minds for more than 2000 years. Differential calculus deals with ideas such as speed, rate of growth, tangent lines, and curvature, whereas integral calculus treats topics such as area, volume, arc length, and centroids.
Work begun by Archimedes in the third century B.C. led ultimately to the birth of integral calculus in the seventeenth century. This development has a long and fascinating history to which we shall return in Chapter 7.
Differential calculus has a relatively short history. Its principles were first formulated early in the seventeenth century when a French mathematician, Pierre de Fermat, tried to devise a way of finding the smallest and largest values of a given function. He imagined the graph of a function having, at each of its points, a direction given by a tangent line, as suggested by the points labeled in Fig. 3.1.
If I wished to attract the student of any of these sciences to an algebra for vectors, I should tell him that the fundamental notions of this algebra were exactly those with which he was daily conversant … In fact, I should tell him that the notions which we use in vector analysis are those which he who reads between the lines will meet on every page of the great masters of analysis, or of those who have probed the deepest secrets of nature.
J W Gibbs, in Nature, 16 March 1893
THE RISE OF VECTOR ANALYSIS
Throughout their history, mathematics and physics have been intimately related; a discovery in one field led to an improvement in the other. Early natural philosophers grappling with quantities such as distance, speed, and time used geometry inherited from the Greeks to explore physical problems. But in the tumultuous years of the seventeenth century, physics underwent a transformation – a shift in emphasis from numerical quantities, such as distance and speed, to vector quantities, such as displacement and velocity, which have direction as well as magnitude.
The transition was neither abrupt nor confined to that century. It was necessary to invent new mathematical objects – vectors – and new mathematical machinery for manipulating them – vector algebra – to embody the properties of the physical quantities they were to represent.
I do not consider these principles to be certain mysterious qualities feigned as arising from characteristic forms of things, but as universal laws of Nature, by the influence of which these very things have been created. For the phenomena of Nature show that these principles do indeed exist, although their nature has not yet been elucidated. To assert that each and every species is endowed with a mysterious property characteristic to it, due to which it has a definite mode in action, is really equivalent to saying nothing at all. On the other hand, to derive from the phenomena of Nature two or three general principles, and then to explain how the properties and actions of all corporate things follow from those principles, this would indeed be a mighty advance in philosophy, even if the causes of those principles had not at the time been discovered.
Roger Boscovich, A Theory of Natural Philosophy (1763)
FORMS OF ENERGY
The concept of energy, as we saw in Chapter 13, is subtle, elegant, and rich. It describes a dynamic property of the universe which is strictly and absolutely conserved; energy can neither be created nor destroyed. Not even in the presence of friction is energy ever lost; it is simply transformed into other forms. Nevertheless, the universe is winding down. Energy tends to be transformed from well-organized forms into more disorganized forms, until it becomes completely useless.