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Đây là bộ sách tiếng anh về chuyên ngành vật lý gồm các lý thuyết căn bản và lý liên quan đến công nghệ nano ,công nghệ vật liệu ,công nghệ vi điện tử,vật lý bán dẫn. Bộ sách này thích hợp cho những ai đam mê theo đuổi ngành vật lý và muốn tìm hiểu thế giới vũ trụ và hoạt độn ra sao.
[...]... published a historical and critical analysis of mechanics in which he rejected Newton’s concept of an absolute space, precisely because it was unobservable Mach demanded that the laws of physics should be based only on concepts which could be related to observations Since motion still had to be referred to some frame at rest, he proposed replacing absolute space by an idealized rigid frame of fixed stars... which would have been too revolutionary at the time Newton’s contemporary and competitor Gottfried Wilhelm von Leibnitz (1646– 1716) also regarded the Universe to be spanned by an abstract infinite space, but in contrast to Newton he maintained that the stars must be infinite in number and distributed all over space, otherwise the Universe would be bounded and have a centre, contrary to contemporary philosophy... (1.19) The Hubble Constant The value of this constant initially found by Hubble was H0 = 550 km s−1 Mpc−1 : an order of magnitude too large because his distance measurements were badly wrong To establish the linear law and to determine the global value of H0 one needs to be able to measure distances and expansion velocities well and far out Distances are precisely measured only to nearby stars which... spotted some errors in the second edition, and who proposed some improvements in case I were writing a third edition This came at the appropriate time and led to a collaboration in which Thomas S Coleman read the whole manuscript, corrected misprints, improved my English, checked my calculations, designed new figures and proposed clarifications where he found the text difficult My wife Jacqueline has many... the whole sky covered by stars viewed by an observer at the centre, An dr Since n is the star count per volume element, An has the dimensions of number of stars per linear distance The inverse of this, = 1 /An, (1.4) is the mean radial distance between stars, or the mean free path of photons emitted from one star and being absorbed in collisions with another We can also define a mean collision time:... more convenient to normalized it to its present value, and thereby define a dimensionless quantity, the cosmic scale factor: (1.16) a(t) ≡ R(t)/R0 The cosmic scale factor affects all distances: for instance the wavelength λ of light emitted at one time t and observed as λ0 at another time t0 : λ λ0 = R0 R(t) Let us find an approximation for a(t) at times t < t0 by expanding it to firstorder time differences,... corrected Herschel made many important discoveries, among them the planet Uranus, and some 700 binary stars whose movements confirmed the validity of Newton’s theory of gravitation outside the Solar System He also observed some 250 diffuse nebulae, which he first believed were distant galaxies, but which he and many other astronomers later considered to be nearby incandescent gaseous clouds belonging to our... static Kant thought that he had settled the argument between Newton and Leibnitz about the finiteness or infiniteness of the system of stars He claimed that either type of system embedded in an infinite space could not be stable and homogeneous, and thus the question of infinity was irrelevant Similar thoughts can be traced to the scholar Yang Shen in China at about the same time, then unknown to Western... (1693–1762) discovered the aberration of starlight, and explained it as due to the changes in the velocity of the Earth in its annual orbit In our time, Newton’s theory of gravitation still suffices to describe most of planetary and satellite mechanics, and it constitutes the nonrelativistic limit of Einstein’s relativistic theory of gravitation Historical Cosmology 3 Newton considered the stars to be suns evenly... was thus dethroned to live on an average-sized planet orbiting around an average-sized sun The stars were understood to be suns like ours with fixed positions in a static Universe The Milky Way had been resolved into an accumulation of faint stars with the telescope of Galileo The anthropocentric view still persisted, however, in locating the Solar System at the centre of the Universe Newton’s Cosmology . Solar System. Humankind was thus dethroned to live on an average-sized planet orbiting around an average-sized sun. The stars were understood to be suns like. Cataloging-in-Publication Data Roos, Matts. Introduction to cosmology / Matt Roos. – 3rd ed. p. cm. Includes bibliographical references and index. ISBN 0-4 7 0-8 490 9-6