- Hendrik Antoon Lorentz (18 July 1853 – 4 February 1928) was a Dutch physicist who shared the 1902 Nobel Prize in Physics with Pieter Zeeman for the discovery and theoretical explanation of the Zeeman effect. - The action of the Royal Society at its meeting in London on November 6, in recognizing Dr. - Albert Einstein's “theory of relativity” has caused a great stir in scientific circles on both sides of the Atlantic. - The present revival of interest in it is due to the remarkable confirmation which it received in the report of the observations made during the sun's eclipse of last May to determine whether rays of light passing close to the sun are deflected from their course.. - The actual deflection of the rays that was discovered by the astro- nomers was precisely what had been predicted theoretically by Einstein many years since. - Einstein himself when he was in- terviewed by a correspondent of the New York Times at his home in Ber- lin. - ‘uniform motion.’ The person would then naturally reach bottom on the opposite side. - According to Galileo and Newton, time and space were absolute entities, and the moving systems of the universe were dependent on this absolute time and space. - The relation of the two is, however, of such a. - But these equa- tions were entangled with the hypothesis of the ether, and with the no- tion of motion relative to the ether. - The mo- tion of the earth relatively to the ether should have been different at dif- ferent points of its orbit, and measurable phenomena should have resul- ted from this difference. - The equations on which the theory of relativity is based are due to Lorentz, but Einstein connected them with his general principle, namely, that there must be nothing, in observable phenomena, which could be attributed to absolute motion of the observer.. - At this point Einstein intervened with a hypothesis which, apart alto- gether from subsequent verification, deserves to rank as one of the great monuments of human genius. - In these geometries the sum of the angles of a triangle is not two right angles, and the departure from two right angles increases as the size of the triangle increases. - Einstein supposes that space is Euclidean where it is sufficiently re- mote from matter, but that the presence of matter causes it to become slightly non-Euclidean—the more matter there is in the neighborhood, the more space will depart from Euclid. - By the help of this hypothesis, together with his previous theory of relativity, he deduces gravita- tion—very approximately, but not exactly, according to the Newtonian law of the inverse square. - There are, so far, three crucial tests of the relative accur- acy of the new theory and the old.. - The results of the observations have now been published, and are found to verify Einstein's prediction. - taking the average of the best series of observations, the deflection at the sun's limb is found to be 1.98″, with a probable error of about 6 per cent., whereas the deflection calculated by Einstein's theory should be 1.75″. - The discrepancy is well within what might be expected in view of the minuteness of the meas- urements. - If his theory is correct as it stands, there ought, in a gravitational field, to be a displacement of the lines of the spectrum towards the red. - The new law has been so amazingly successful in two of the three tests that there must be some thing valid about it, even if it is not exactly right as yet.. - Einstein's theory has the very highest degree of aesthetic merit: every lover of the beautiful must wish it to be true. - It gives a vast unified sur- vey of the operations of nature, with a technical simplicity in the critical assumptions which makes the wealth of deductions astonishing. - It is a case of an advance arrived at by pure theory: the whole effect of Einstein's work is to make physics more philosophical (in a good sense), and to restore some of that intellectual unity which belonged to the great scientific systems of the seventeenth and eighteenth centuries, but which was lost through increasing specialization and the overwhelming mass of detailed knowledge. - Lorentz, of the University of Leyden. - The total eclipse of the sun of May 29, resulted in a striking confirma- tion of the new theory of the universal attractive power of gravitation de- veloped by Albert Einstein, and thus reinforced the conviction that the defining of this theory is one of the most important steps ever taken in the domain of natural science. - For centuries Newton's doctrine of the attraction of gravitation has been the most prominent example of a theory of natural science.. - Through the simplicity of its basic idea, an attraction between two bodies proportionate to their mass and also proportionate to the square of the distance. - through the completeness with which it explained so many of the peculiarities in the movement of the bodies making up the solar sys- tem. - and, finally, through its universal validity, even in the case of the far-distant planetary systems, it compelled the admiration of all.. - But, while the skill of the mathematicians was devoted to making more exact calculations of the consequences to which it led, no real pro- gress was made in the science of gravitation. - While in electric effects an influence exercised by the matter placed between bodies was speedily observed—the starting-point of a new and fertile doctrine of electricity—in the case of gravitation not a trace of an influence exercised by intermediate matter could ever be discovered. - Only when we look at ob- jects outside the train, or when the air can enter the car, do we notice in- dications of the motion. - In place of the air now comes, so it was reasoned formerly, the ether which fills the spaces of the universe and is the carrier of light and of electro-magnetic phenomena. - all the phenomena examined were evidently independent of the motion of the earth. - If the spaces of the universe are filled with an ether, let us suppose with a substance, in which, aside from eventual vibrations and other slight movements, there is never any crowding or flowing of one part alongside of another, then we can imagine fixed points existing in it. - If, consequently, one of the points is chosen as an “original point” we can, proceeding from that point, reach any other point through three steps in the common perpendicular directions in which the points are arranged. - The figures showing how many meters are com- prized in each of the steps may serve to indicate the place reached and to distinguish it from any other. - In this “system of co-ordinates” the numbers that fix the position of one or the other of the bodies may now be read off at any moment.. - This is the means which the astronomers and their mathematical as- sistants have always used in dealing with the movement of the heavenly bodies. - Thus the picture that one forms of the phenomena stands there as if it were sketched on the canvas of the motionless ether.. - Since Einstein has cut loose from the ether, he lacks this canvas, and therewith, at the first glance, also loses the possibility of fixing the posi- tions of the heavenly bodies and mathematically describing their move- ment—i.e., by giving comparisons that define the positions at every mo- ment. - On the surface of the earth the attraction of gravitation causes all bod- ies to fall along vertical lines, and, indeed, when one omits the resistance of the air, with an equally accelerated movement. - The relative movement of the body with regard to the measure should be without ac- celeration, and if we had to judge only by what we observed in the spot where we were and which was falling itself, then we should get the im- pression that there was no gravitation at all. - If the measure goes down with an acceleration equal to a half or a third of what it just was, then the relative motion of the body will, of course, be accelerated, but we should find the increase in velocity per second one-half or two-thirds of 981. - Thus we see that we, also when the measure is not attached to the earth, disregarding its displacement, may describe the motion of the body in respect to the measure always in the same way—i.e., as one uni- formly accelerated, as we ascribe now and again a fixed value to the ac- celeration of the sphere of gravitation, in a particular case the value of zero.. - But in the spaces of the solar system we have, now that we have abandoned the ether, no such support. - That in all these cases for fixed bodies that do not participate in the movement or the remodelling of the system other co-ordinates will be read off again and again is clear.. - Therefore he made it his aim so to arrange the theory that, no matter how the choice was made, the phenomena of gravitation, so far as its effects and its stimulation by the attracting bodies are con- cerned, may always be described in the same way—i.e., through compar- isons of the same general form, as we again and again give certain values to the numbers that mark the sphere of gravitation. - (For the sake of sim- plification I here disregard the fact that Einstein desires that also the way in which time is measured and represented by figures shall have no in- fluence upon the central value of the comparisons.). - it appeared necessary for the fixation of the field of gravitation in one or the other point in space to introduce no fewer than ten quantities in the place of the one that occurred in the ex- ample mentioned above.. - the principle of the freedom of choice in co-ordinates was the only one by which he needed to allow himself to be guided. - Although thus there was no special effort made to reach a connection with the theory of Newton, it was evident, fortunately, at the end of the experiment that the connection existed. - If we avail ourselves of the simplifying circumstance that the velocities of the heavenly bodies are slight in comparison with that of light, then we can deduce the theory of Newton from the new the- ory, the “universal” relativity theory, as it is called by Einstein. - Now, there was a difficulty in the movement of the planet Mercury which could not be solved. - attraction of other planets had been taken into account, there remained an inexplicable phenomenon—i.e., an extremely slow turning of the el- lipsis described by Mercury on its own plane. - Thus with a single blow he solved one of the greatest puzzles of astronomy.. - Still more remarkable, because it has a bearing upon a phenomenon which formerly could not be imagined, is the confirmation of Einstein's prediction regarding the influence of gravitation upon the course of the rays of light. - If we limit the light to a flicker of the slightest duration, so that only a little bit, C, of a ray of light arises, or if we fix our attention upon a single vibration of light, C, while we on the other hand give to the pro- jectile, B, a speed equal to that of light, then we can conclude that B and C in their continued motion can always remain next to each other. - The bending of a ray of light thus described is much too light on the sur- face of the earth to be observed. - But the attraction of gravitation exer- cised by the sun on its surface is, because of its great mass, more than twenty-seven times stronger, and a ray of light that goes close by the su- perficies of the sun must surely be noticeably bent. - The rays of a star that are seen at a short distance from the edge of the sun will, going along the sun, deviate so much from the original direction that they strike the eye of an observer as if they came in a straight line from a point somewhat further removed than the real position of the star from the sun. - The Einstein theory teaches that the displace- ment is in inverse proportion to the apparent distance of the star from the centre of the sun, and that for a star just on its edge it will amount to seconds). - This is approximately the thousandth part of the apparent diameter of the sun.. - Naturally, the phenomenon can only be observed when there is a total eclipse of the sun. - then one can take photographs of neighboring stars and through comparing the plate with a picture of the same part of the heavens taken at a time when the sun was far removed from that point the sought-for movement to one side may become apparent.. - Thus to put the Einstein theory to the test was the principal aim of the English expeditions sent out to observe the eclipse of May 29, one to Prince's Island, off the coast of Guinea, and the other to Sobral, Brazil.. - The first-named expedition's observers were Eddington and Cottingham, those of the second, Crommelin and Davidson. - In the report is- sued regarding the results the following figures, which are the average of the measurements made from the seven plates, are given for the dis- placements of seven stars:. - If we consider that, according to the theory the displacements must be in inverse ratio to the distance from the centre of the sun, then we may deduce from each observed displacement how great the sideways move- ment for a star at the edge of the sun should have been. - As the last of the displacements given above—i.e., 0 ″ .24 is about one-eighth of this, we may say that the influ- ence of the attraction of the sun upon light made itself felt upon the ray at a distance eight times removed from its centre.. - The displacements calculated according to the theory are, just because of the way in which they are calculated, in inverse proportion to the dis- tance to the centre. - The proportion of the first and the last observed sidewise movements is 4.2, and that of the two most extreme of the cal- culated numbers is 4.4.. - Indeed, such a refraction should cause a deviation in the observed direction, and, in order to produce the displacement of one of the stars under observation itself a slight proximity of the vapor ring should be sufficient, but we have every reason to expect that if it were merely a question of a mass of gas around the sun the diminishing effect accom- panying a removal from the sun should manifest itself much faster than is really the case. - We cannot speak with perfect certainty here, as all the factors that might be of influence upon the distribution of density in a sun atmosphere are not well enough known, but we can surely demon- strate that in case one of the gasses with which we are acquainted were held in equilibrium solely by the influence of attraction of the sun the phenomenon should become much less as soon as we got somewhat fur- ther from the edge of the sun. - If the displacement of the first star, which amounts to 1.02-seconds were to be ascribed to such a mass of gas, then the displacement of the second must already be entirely inappreciable.. - So far as the absolute extent of the displacements is concerned, it was found somewhat too great, as has been shown by the figures given above. - it also appears from the final result to be 1.98 for the edge of the sun—i.e., 13 per cent, greater than the theoretical value of 1.75. - (The observations made with a second instrument at Sobral gave a res- ult of 0.93, but the observers are of the opinion that because of the shift- ing of the mirror which reflected the rays no value is to be attached to it.). - During a discussion of the results obtained at a joint meeting of the Roy- al Society and the Royal Astronomical Society held especially for that purpose recently in London, it was the general opinion that Einstein's prediction might be regarded as justified, and warm tributes to his geni- us were made on all sides. - Any one reading it will, in my opinion, come to the conclusion that the basic ideas of the theory are really clear and simple. - It is true that, according to Einstein's theory, because it leaves us entirely free as to the way in which we wish to represent the phenomena, we can imagine an idea of the solar system in which the planets follow paths of peculiar form and the rays of light shine along sharply bent lines—think of a twisted and distorted planetarium—but in every case where we apply it to concrete questions we shall so arrange it that the planets describe al- most exact ellipses and the rays of light almost straight lines.. - Especially in former years were such in- terpretations current and repeated attempts were made by speculations about the nature of the ether and about the mutations and movements that might take place in it to arrive at a clear presentation of electro-mag- netic phenomena, and also of the functioning of gravitation. - Nevertheless, even without the color and clearness that the ether the- ories and the other models may be able to give, and even, we can feel it this way, just because of the soberness induced by their absence, Einstein's work, we may now positively expect, will remain a monument of science. - He attended the last meeting of the de- partment of natural philosophy of the Royal Academy of Sciences, and the members then had the privilege of hearing him explain, in his own fascinating, clear and simple way, his interpretations of the fundamental questions to which his theory gives rise.. - Public speaking is public utter- ance, public issuance, of the man himself. - Unless there be something of value within, no tricks of training can ever make of the talker anything more than a machine--albeit a highly perfected machine--for the delivery of other men's goods. - Beyond Good and Evil (German: Jenseits von Gut und Böse), sub- titled "Prelude to a Philosophy of the Future". - knowledge and the perilous condition of the modern individual.. - A portion of the work consists of practical advice on sex. - is attributed to Nandi the sacred bull, Shiva's doorkeeper, who was moved to sac- red utterance by overhearing the lovemaking of the god and his wife Parvati and later recorded his utterances for the benefit of mankind.. - Charles Darwin's On the Origin of Species, in which he writes of his theories of evolution by natural selection, is one of the most important works of scientific study ever published.. - The Art of War is one of the oldest books on military strategy in the world. - It is the first and one of the most successful works on strategy and has had a huge influence on Eastern and Western military thinking, business tactics, and beyond. - The United States Declaration of Independence is a statement ad- opted by the Continental Congress on July 4, 1776, announcing that the thirteen American colonies then at war with Great Britain were no longer a part of the British Empire. - Written primarily by Thomas Jefferson, the Declaration is a formal explanation of why Congress had voted on July 2 to declare independence from Great Britain, more than a year after the outbreak of the American Re- volutionary War. - The birthday of the United States of Amer- ica—Independence Day—is celebrated on July 4, the day the wording of the Declaration was approved by Congress.. - An Inquiry into the Nature and Causes of the Wealth of Nations. - Adam Smith's masterpiece, first published in 1776, is the founda- tion of modern economic thought and remains the single most im- portant account of the rise of, and the principles behind, modern capitalism
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