‎Physique‎

‎"BOHR, N(IELS).‎

‎On the Theory of the Decrease of Velocity of Moving Electrified Particles on passing through Matter. [Off-print From the Philosophical Magazine (Vol. 25, No. 145) for January 1913 ]. - [THE FOUNDATION OF BOHR'S ATOMIC THEORY - PRESENTATION-COPY]‎

‎[London, Taylor & Francis], 1913. 8vo. Original printed wrappers. The fragile wrappers are detached, but fully intact. Merely tiny parts of the thin backstrip lacking. Three small tears to front wrapper, no loss, as well as a couple of creses. Back wrapper with a slight bend to the corner and minor fading to extremities. Pp. (9)-31.‎

‎Scarce first edition, off-print issue with presentation-inscription, of Bohr's seminal first work on nuclear physics, being the work that lays the foundation for his atomic theory (published before his ""On the Constitution of Atoms and Molecules""), in which he is able to conclude ""that a hydrogen atom contains only 1 electron outside the positively charged nucleus, and that a helium atom only contains 2 electrons outside the nucleus ."" ""Bohr's 1913 paper on alpha-particles [i.e. the present], which he had begun in Manchester, and which had led him to the question of atomic structure, marks the transition to his great work, also of 1913, on that same problem. While still in Manchester, he had already begun an early sketch of those entirely new ideas."" (Pais, p. 128). The present work must be considered one of the most important to the birth of modern atomic theory.The work is inscribed to renowned Danish physicist and meteorologist Dan la Cour (1876-1942), son of the great Poul la Cour (1846-1908), who is considered the ""Danish Edison"". The inscription reads as thus: ""Hr. Docent Afdelingschef D. la Cour/ med venlig Hilsen/ fra/ Forfatteren."" [In Danish, i.e.: ""Mr. Assistant Professor Head of Department D. la Cour/ with kind regards/ from/ the author.""].Dan la Cour was the assistant of Niels Bohr's father, Christian Bohr, and a well known scientist. From 1903, he was head of the department of the Meteorological Institute, and from 1923 leader thereof. From 1908 he was Associate Professor at the Polytechnic College. His original scientific works are highly respected, as are his original apparati for measuring earth magnetism which are considered highly valuable. ""His original intelligence, which in many ways resemble that of his father, also bore fruit in his patenting of various inventions: the ""Pyknoprobe"", developed to quickly determine the different layers of the sea"" a use of termite in quickly heating food and drinks out in the open under unfavourable weather conditions."" (From the Danish Encyclopaedia - own translation). He wrote a number of important and esteemed works and was member of the Danish Scientific Academy as well as many prominent international scientific commissions of meteorology and geophysics (i.e. president of the International Geodetical and Geophysical Union). He was also honorary Doctor at the George Washington University. After finishing his studies in Copenhagen, Bohr went to Cambridge in order to pursue his studies on electron theory under the guidance of J.J. Thompson. Thompson, who was beginning to lose interest in the subject by now, did, however, not recognize the genious of the young Bohr, and as soon as he could, Bohr went to Manchester, where Ernest Rutherford had established a laboratory. ""There, from March to July 1912, working with utmost concentration, he [i.e. Bohr] laid the foundation for his greatest achievements in physics, the theory of the atomic constitution."" (DSB). Bohr's survey of the implications of Rutherford's atomic model had led him to attack the much harder problem which lay at the core of it, namely determining the exact nature of the relation between the atomic number and the number of electrons in the atom. ""Bohr obtained a much deeper insight into the problem by a brilliant piece of work, which he - working, as he said, ""day and night"" - completed with astonishing speed"" (DSB), that paper being the present ""On the Theory of the Decrease of Velocity of Moving electrified Particles on passing through Matter"", which thus constitutes his very first publication on the subject, published immediately after this dense period of 1912, in the Philosophical Magazine of January 1913. ""The problem was one of immediate interest for Rutherford's laboratory: in their passage through a material medium, alpha particles continually lose energy by ionizing the atoms they encounter, at a rate depending on their velocity. Their energy loss limits the depth to which the particles can penetrate into the medium, and the relation between this depth, or range, and the velocity offers a way of determining this velocity. What Bohr did was to analyze the ionizing process on the basis of the Rutherford model of the atom and thus express the rate of energy loss in terms of the velocity by a much more accurate formula than had so far been achieved-a formula, in fact, to which modern quantum mechanics adds only nonessential refinements"" (DSB). In the present work, Bohr was thus able to conclude: ""In this paper the theory of the decrease of velocity of moving electrified particles in passing through matter is given in a form, such that the rate of the decrease in the velocity depends on the frequency of vibration of the electrons in the atoms of the absorbing material."" as well as the seminal words that have been formative for the birth of the modern atomic theory: ""Adopting Prof. Rutherford's theory of the constitution of atoms, it seems that it can be concluded with great certainty, from the absorption of alpha-rays, that a hydrogen atom contains only 1 electron outside the positively charged nucleus, and that a helium atom only contains 2 electrons outside the nucleus "". Bohr continues: ""These questions and some further information about the constitution of atoms which may be got from experiments on the absorption of alpha-rays, will be discussed in more detail in a later paper."" (pp. 30-31 of the original paper) - the last sentence referring directly to his three part ""On the Constitution of Atoms and Molecules"", in which he went on to present his postulates of the orbital structure of the electrons and their quantized radiation. Rosenfeld, Bohr Bibliography No. 5. Rosenfeld, Dictionary of Scientific Biography II, pp. 240-41. Pais, Niels Bohr's Times, pp. 117-31.‎

Référence libraire : 45726

‎"BOHR, N. (+) D. COSTER [DIRK].‎

‎Röntgenspektren und periodisches System der Elemente. Mit vier Abbildungen.‎

‎Berlin, Julius Springer, 1923. 8vo. Contemp. hcloth. A stamp to titlepage. Entire volume 12 of ""Zeitschrift für Physik"". IV, 380 pp. Entire volume offered). The paper: pp. 342-75. Internally clean and fine.‎

‎"BOHR, N. (+) D. COSTER [DIRK].‎

‎Röntgenspektren und periodisches System der Elemente. Mit vier Abbildungen.‎

‎Berlin, Julius Springer, 1923. 8vo. Entire volume 12 of ""Zeitschrift für Physik"" bound in contemporary black half cloth with gilt title to spine. Library stamp to title-page and paper label pasted on to lower part of spine. Minor wear to extremities. A nice and clean copy. Pp. 342-75. [Entire volume: IV, 380 pp.].‎

‎First printing of Bohr's conceptions about atomic structure including electronic orbits. The paper was written in the months during which element 72 was discovered (first named Hafnia, the Latin name for Copehagen, then Danium, and finally the official name became Hafnium), and in the paper, element 72 is mentioned but not named. This is Bohr's first paper with joint authorship.""Element 72 is included, but it is still indicated as unknown. In the second section of the paper a classification is given of the known X-ray spectra of 48 elements, from magnesium to uranium."" (Bohr. Collected Works: The periodic system (1920-1923), p. 33).The volume also contains the following paper by Erwin Schrödinger:""Über eine bemerkenswerte Eigenschaft der Quantenbahnen eines einzelnen Elektrons"" in which he made a new remarkable characteristic of the quanta channnel of a single electron.‎

Référence libraire : 43717

‎"BOHR, N. (+) D. COSTER [DIRK].‎

‎Röntgenspektren und periodisches System der Elemente. Mit vier Abbildungen.‎

‎Berlin, Julius Springer, 1923. 8vo. Bound in contemporary half cloth with gilt lettering to spine. In ""Zeitschrift für Physik"", 12 band, 1923. The entire volume offered. Library stamp to title page. Internally a fine and clean copy. Pp. 272-286. [Entire volume: IV, 383 pp.].‎

‎First printing of Bohr's conceptions about atomic structure including electronic orbits. The paper was written in the months during which element 72 was discovered (first named Hafnia, the Latin name for Copehagen, then Danium, and finally the official name became Hafnium), and in the paper, element 72 is mentioned but not named. This is Bohr's first paper with joint authorship.""Element 72 is included, but it is still indicated as unknown. In the second section of the paper a classification is given of the known X-ray spectra of 48 elements, from magnesium to uranium."" (Bohr. Collected Works: The periodic system (1920-1923), p. 33).The volume also contains the following paper by Erwin Schrödinger:""Über eine bemerkenswerte Eigenschaft der Quantenbahnen eines einzelnen Elektrons"" in which he made a new remarkable characteristic of the quanta channnel of a single electron.‎

Référence libraire : 49489

‎"BOHR, N. (+) J. A. WHEELER (+) J. R. OPPENHEIMER (+) H. SNYDER.‎

‎The mechanism of nuclear fission [N. Bohr. & J. A. Wheeler] ""On continued gravitational contraction"" [J. R. Oppenheimer & H. Snyder]. - [THE FIRST THEORETICAL DESCRIPTION OF A SINGULARITY]‎

‎Lancaster, American Institute of Physics, 1939. Royal8vo. In the original green printed wrappers. In ""The Physical Review"", Volume 56, Second Series, Number 5, September 1. With cloth back-strip. A quire, affecting both papers, detached but without any loss of paper. A few minor tear throughout, far from affecting text. [Bohr & Wheeler:] Pp. 426-50. [Oppenheimer & Snyder:] Pp. 455-59. [Entire volume: Pp. 387-486].‎

‎First printing of two landmark papers, all of seminal importance in history of physics: The intricacies of the fission process, the groundwork for atomic and hydrogen bombs and the forgotten birth of black holes: The first theoretical description of a black hole, the production of a singularity when a sufficiently large neutron star collapses.Oppenheimer and Snyder's ""ON CONTINUED GRAVITATIONAL CONTRACTION"" constitute the very first theoretical prediction of a singularity when a sufficiently large neutron star collapses. This phenomenon was later to be coined as a black hole. ""Had J. Robert Oppenheimer not led the US effort to build the atomic bomb, he might still have been remembered for figuring out how a black hole could form."" (American Physical Society). The paper has by several physics historians been described as the forgotten birth of black holes. ""Oppenheimer and his graduate student George Volkoff presented the first analysis of the formation of a neutron star in a 1939 Physical Review paper titled, ""On Massive Neutron Stars"". Oppenheimer wondered what would happen to a very massive neutron star. The Schwartzschild analysis of General Relativity has a theoretical limit, called the ""Schwartzschild limit"", when the ratio of mass-to-radius of a star is 236,000 times greater than the ratio for our sun. When this limit is exceeded, the Schwartzschild analysis does not yield a solution. Oppenheimer believed that a neutron star could have sufficient mass to exceed this limit. What would happen to it? Oppenheimer and his graduate student Hartland Snyder applied General Relativity theory to a star with sufficient mass and density to exceed the Schwartzschild limit. The Schwartzschild analysis assumed that the size of the star stays constant with time. Oppenheimer and Snyder found that they could achieve a real solution from General Relativity when the Schwartzschild limit is exceeded by assuming that the diameter of the star decreases with time. They presented their analysis in a 1939 Physical Review paper, titled, ""On Continual Gravitational Contraction,"" which concluded with: ""When all thermonuclear sources of energy are exhausted, a sufficiently heavy star will collapse. Unless fission due to rotation, the radiation of mass, or the blowing off of mass by radiation, reduce the star's mass to the order of that of the sun, this contraction will continue indefinitely."" This analysis concluded that when the Schwartzschild limit is exceeded, the star must collapse indefinitely until it reaches a singularity having an infinite density of matter"" (Bjornson, Singularity Predictions of General Relativity, P. 4).The Chandrasekhar / Eddington controvery in the mid 30ies did discuss the fate of neutron stars but the first thoroughly theoretical desciption was first published here. ""THE MECHANISM OF NUCLEAR FISSION"" is the first fully worked out theory of nuclear fission, which laid the groundwork for atomic and hydrogen bombs.""Wheeler's technical mastery of physics is best seen in the classic paper of Bohr and Wheeler. Bohr and Wheeler wrote the paper in Princeton, where Bohr was visiting in the spring of 1939, a few months after the discovery of fission. The paper is a masterpiece of clear thinking and lucid writing. It reveals, at the center of the mystery of fission, a tiny world where everything can be calculated and everything understood. The tiny world is a nucleus of uranium 236, formed when a neutron is freshly captured by a nucleus of uranium 235. The uranium 236 nucleus sits precisely on the border between classical and quantum physics. Seen from the classical point of view, it is a liquid drop composed of a positively charged fluid. The electrostatic force that is trying to split it apart is balanced by the nuclear surface tension that is holding it together. The energy supplied by the captured neutron causes the drop to oscillate in various normal modes that can be calculated classically. Seen from the quantum point of view, the nucleus is a superposition of a variety of quantum states leading to different final outcomes. The final outcome may be a uranium 235 nucleus with a re-emitted neutron, or a uranium 236 nucleus with an emitted gamma-ray, or a pair of fission-fragment nuclei with one or more free neutrons. Bohr and Wheeler calculate the cross-section for fission of uranium 235 by a slow neutron and get the right answer within a factor of two. Their calculation is a marvelous demonstration of the power of classical mechanics and quantum mechanics working together. By studying this process in detail, they show how the complementary views provided by classical and quantum pictures are both essential to the understanding of nature. Without the combined power of classical and quantum concepts, the intricacies of the fission process could never have been understood. Bohr's notion of complementarity is triumphantly vindicated"" (John Archibald Wheeler, Proceedings of the American Philosophical Society 154 (2010)).‎

Référence libraire : 54015

‎"BOHR, N. (NIELS). - THE ATOMIC MODEL AND THE ""STATIONARY STATE""‎

‎On the Quantum Theory of Radiation and the Structure of the Atom. (+) On the Decrease of velocity of Swiftly Moving Electrified Particles passing through Matter. (2 papers).‎

‎London, Taylor & Francis, 1915. Contemp. hcalf. Spine gilt, title- and tomelabels with gilt lettering. Spine a bit rubbed, some cracking to hinges, but covers not detached. In: ""The London, Edinburgh, and Dublin Philosophical Magazine and Journal of Science"", Vol. XXX, Sixth Series. VIII,824 pp., textillustr. and 18 plates. (Entire volume offered). Bohr's papers: pp. 394-413 and pp. 581-612. A stamp to verso of titlepage. Internally clean and fine.‎

‎"BOHR, NIELS (+) H.A. KRAMERS (+) J.C. SLATER.‎

‎Über die Quantentheorie der Strahlung. (The quantum theory of radiation). - [TOWARDS QUANTUM MECHANICS]‎

‎Braunschweig, Berlin, Vieweg & Sohn u. Julius Springer, 1924. 8vo. Bound in contemporary halfcloth. In ""Zeitschrift für Physik"", Bd. 23 & 24. (Entire volume offered). No stamps, not an ex library copy. Fine and clean. Pp.69-87. [Entire volume: IV,412 pp].‎

‎"BOHR, NIELS (+) H.A. KRAMERS (+) J.C. SLATER.‎

‎Über die Quantentheorie der Strahlung. (The quantum theory of radiation). - [TOWARDS QUANTUM MECHANICS]‎

‎Braunschweig, Berlin, Vieweg & Sohn u. Julius Springer, 1924. 8vo. Bound in contemporary halfcloth. In ""Zeitschrift für Physik"", Bd. 23 & 24. (Entire volume offered). No stamps, not an ex library copy. Fine and clean. Pp.69-87. [Entire volume: IV,412 pp].‎

‎First apperance (simultaneously printed in Philosophical Magazine) of a fundamental paper in the development of the Quantum Theory. Three fundamental ideas were set forth here: 1. Slater's idea of 'a Virtual radiation field', 2. statistical conservation of energy and momentum, and 3. statistical independence of the processes of emission and absorption in distant atoms. (See Van der Waerden ""Sources of Quantum Mechanics"" No. 5).""In an effort to reconcile the particulate and wavelike properties of radiation, Bohr, Kramers, and Slater in 1924 formulated a new quantum theory of radiation. According to their hypothesis, momentum and energy-are conserved only statistically in interactions between radiation and matter."".The present paper became a great influence to Bothe and his Compton collisions and the Coincidence method which eventually resulted in him being awarded the Nobel Prize in Physics.‎

Référence libraire : 48981

‎"BOHR, NIELS (+) HENRY MOSELEY.‎

‎On the Constitution of Atoms and Molecules. 3 Parts (all). (+) The High-Frequency Spectra of the Elements. - [THE BIRTH OF MODERN ATOMIC THEORY (PMM 411)]‎

‎London, Taylor & Francis, 1913. 8vo. Bound in one nice contemporary half calf binding with gilt leather title-label to spine. Published in ""The London, Edinburgh, and Dublin Philosophical Magazine and Journal of Science"", Vol. 26. No. 151-156 offered. Small repair to spine and blind stamped to lower part of title page. Front hindge a bit loose. A fine copy. The Bohr papers: pp. 1-25" pp. 476-502 pp. 857-875. [Moseley:] Pp. 1024-1034. [Entire volume: VIII, 1064 pp.+ 24 plates].‎

‎First edition of Bohr's seminal main work, which constitutes the departure from classical theories to the birth of modern atomic physics" by incorporating Planck's quantum postulate it became possible to calculate the wavelength of the hydrogen emission and thus to explain the regularity of the Balmer-lines. In 1922 Bohr was awarded the Nobel Prize ""for his services in the investigation of the structure of atoms and of the radiation emanating from them"".""Bohr's three-part paper postulated the existence of stationary states of an atomic system whose behavior could be described using classical mechanics, while the transition of the system from one stationary state to another would represent a non-classical process accompanied by emission or absorption of one quantum of homogeneous radiation, the frequency of which was related to its energy by Planck's equation"" (Norman).In his previous paper (""On the Theory of Decrease of Velocity of Moving Electrified Particles on passing through Matter"") Bohr had adopted Rutherford's nuclear model of the atom, and had become convinced that it was the peripherical electrons that determined the chemical properties of an element, whereas the nucleus determine the radioactive properties. However, Rutherford's model had an apparent explanatory problem: Why were the negatively charged electrons held away from the positive nucleus? In his doctorial dissertation on the electron theory of metals, Bohr had clarified the limitations of this theory, in particular its ability to explain magnetic properties, and he had shown how this arose from the classical nature of some of its foundations. Bohr strongly expected that the key to solving this problem was to be found in some way of introducing Planck's law of quantum action.In the beginning of 1913 Bohr heard about Rydberg's remarkable discovery in spectroscopy. Rydberg's formula could represent the frequencies of the lines of the hydrogen spectrum in the simplest form in terms of two integers. As soon as Bohr saw this formula, he immediately recognized that it gave him the missing clue to the correct way to introduce Planck's law of quantum of action into the description of the atomic systems. The rest of the academic year was spent reconstructing the whole theory upon the new foundation and expounding it in a large treatise, which was immediately published as these three papers in the 'Philosophical Magazine'. It was in these papers that Bohr first gave his postulates of the orbital structure of the electrons and their quantized radiation.Bohr's atomic theory inaugurated two of the most adventurous decades in the history of science. Bohr introduced the following postulates: 1. An electron can revolve about its nucleus only in certain special circular orbits. 2. The ordinary electron revolves about its nucleus in an invariable orbit, without radiating or absorbing energy. 3. Radiation takes place when and only when the electron falls from an orbit with greater energy to one of less energy.""In his great papers of 1913, Bohr presented his theory as being founded upon two postulates, whose formulation he refined in later papers. The first postulate enunciates the existence of stationary states of an atomic system, the behavior of which may be described in terms of classical mechanics" the second postulate states that the transition of the system from one stationary state to another is a nonclassical process, accompanied by the emission or absorption of one quantum of homogeneous radiation, whose frequency is connected with its energy by Planck's equation. As for the principle by which the possible stationary states are selected, Bohr was still very far from a general formulation" indeed, he was keenly aware of the necessity of extending the investigation to configurations other than the simple ones to which he had restricted himself. The search for sufficiently general quantum conditions defining the stationary states of atomic systems was going to be a major problem in the following period of development of the theory."" (DSB).Also contained in the volume is Henry Moseley's famous paper ""The High-Frequency Spectra of the Elements"" in which he ""used the method of X-ray spectroscopy devised by Braggs to calculate variations in the wave length of the rays emitted by each element. These he was able to arrange in a series according to the nuclear charge of each element. [...] It was now possible to base the periodic table on a firm foundation, and to state with confidence that the number of elements up to uranium is limited to 92."" (PMM 407).PMM 411Rosenfeld, Bohr Bibliography No. 6.‎

Référence libraire : 51728

‎"BOHR, NIELS - NAMING ""THE PRINCIPLE OF CORRESPONDENCE""‎

‎Über die Serienspektra der Elemente. (Vortrag gehalten am 27. April 1920 in der Sitzung der Deutschen Physikalischen Gesellschaft in Berlin).‎

‎Braunschweig, Vieweg & Sohn, 1920. Contemp. Hcloth. Stamp on titlepage. In ""Zeitschrift für Physik"", Bd. 2. IV,478 pp. (Entire volume offered). Bohr's paper: pp. 423-469. A very faint dampstain to right margins.‎

‎First edition of this fundamental paper in which Bohr for the first time gives name to a theory, which was for the first time used in his work ""The quantum theory of line Spectra"" from 1918, but now for the first time called ""Korrespondenzprincip"" (The Principle of Correspondence) and explained in the offered paper. The principle was introduced ""in order to obtain the necessary relation to the ordinary theory of radiation in the limit of slow vibrations we are therefore led directlyto certain conclusions about the probability of transition between two stationary states in this limit."".The ""Principle of Correspondence"" is the physical priciple that the behaviour of atomic and other systems should approximate to that predicted by classical physics in certain specific circumstances where quantum effects are expected to be unimportent. Bohr used the principle to explain his theory of the hydrogen atom, which among other things successfully predicted many features of the spectrum of light emitted by energetic hydrogen atoms. The principle formed an importent component of the early quantum theory of Bohr, Sommerfeld and others.Betty Schultz: 17.‎

Référence libraire : 48726

‎"BOHR, NIELS AND F. KALCKAR. - THE LIQUID DROP MODEL OF BOHR INTRODUCED.‎

‎On the Transmutation of Atomic Nuclei by Impact of Material Particles. I. General theoretical Remarks. (all published)‎

‎Copenhagen, Levin & Munksgaard,1937. 8vo. Uncut in orig. printed wrappers. In: ""Det KGL. Danske Videnskabernes Selskab. Mathematisk-fysiske Meddelelser. XIV,10"". 40 pp. Fine and clean.‎

‎First edition of the work in which Bohr introduced his famous Liquid Drop Model of the atom in order to interprete the nuclear structure. (The paper was not continued as Kalckar died the following year).""It had, of course, been clear to Bohr that analogies with atomic spectra could not be of help in interpreting his (earlier) picture of nuclear structure. Peripheral electrons, thinly spread within the atomic volume, can be compared to a dilute gas of particles interacting in pairs only. By contrast Bohr's picture of intranuclear motions of tightly bound nucleons should show 'essential collective aspects', he said. Now, together with Kalckar, he suggested that for nuclei a much more proper comparison would be with a drop of liquid. That analogy should not be taken too literally, the dynamics of a true liquid drop is vastly different from thta of nucleai. Yet the comparison, treated cautiously, was tempting and in the event proved fruitful in many respects, particularly in regard to collective motions.""(Pais ""Niels Bohr's Times"", pp. 339-40).""In the liquid drop model, formulated by Niels Bohr, the nucleons are imagined to interact strongly with each other, like the molecules in a drop of liquid. A given nucleon collides frequently with other nucleons in the nuclear interior, its mean free path as it moves about being substantially less than the nuclear radius. This constant ""jiggling around"" reminds us of the thermal agitation of the molecules in a drop of liquid. The liquid drop model permits us to correlate many facts about nuclear masses and binding energies"" it is useful in explaining nuclear fission. It also provides a useful model for understanding a large class of nuclear reactions."" (FAQ).Rosenfeld No 56.‎

Référence libraire : 48816

‎"BOHR, NIELS und L. ROSENFELD.‎

‎Zur Frage der Messbarkeit der elektromagnetischen Feldgrössen.‎

‎København (Copenhagen), Levin & Munksgaard, 1933. Orig. printed wrappers. Backstrip with 2 small nicks and frontcover a bit faded at margins. 65 pp. (Det Kgl. Danske Videnskabernes Selskab, Mathematisk-fysiske Meddelelser XII,8).‎

‎First edition of this fundamental papers in the development of quantum field theory. The process of measuring electromagnetic fields involves the observation of charged test bodies in those fields. Therefore the theory of electrodynamics is an inseparable extension of mechanics. A quantum theory of fields thus inherits, in some form, the limitations of measurement which lie at the foundation of quantum mechanics. In 1931 Landau and Peierls published a critical analysis of the consequences of such limitations in a relativistic quantum theory of fields. Landau and Peierls came to the negative conclusion that in several cases, the concept of momentum was without physical meaning and quantities such as the strength of a field was un-measurable. In their famous paper from 1933 Bohr and Rosenfeld (the work offered) carefully reviewed the arguments of Landau and Peierls and showed, through the use of particular measuring arrangements, that a consistent quantum theory of fields is possible without further limitations than the ones which secure the consistency of quantum mechanics. The BR-paper is often credited with having laid the foundation for quantum electrodynamics. Bohr continued his work in this field, and in 1937 he completed a manuscript entitled ""Field and Charge Measurement in Quantum Theory"", but this was never published. When, in the late 1940s the important work on QED by Tomonaga, Schwinger, Dyson, and Feynman appeared in The Physical Review, Bohr and Rosenfeld again joined and published the essentials of the 1937 manuscript in the same journal.See Abraham Pais: Bohr's Times, pp.358-364. Mehra & Rechenberg: The Historical Development of Quantum Theory, vol. 6, pp.697-703. Collected Works of Niels Bohr, vol. 7, pp.3-33.‎

Référence libraire : 38701

‎"BOHR, NIELS.‎

‎Abhandlungen über Atombau aus den Jahren 1913-1916.‎

‎Braunschweig, Friedr. Vieweg, 1921. Uncut in orig. printed wrappers. Lower right corner of frontwrapper gone, no loss of text. 2 small nicks in upper part of frontwrapper. Some of the first quires loosening. XX, 156 pp. Internally clean. Backstrip intact.‎

‎"BOHR, NIELS.‎

‎Atomernes Bygning og Stoffernes fysiske og kemiske Egenskaber.‎

‎Copenhagen: Jul. Gjellerup, 1922 8vo. In the original printed wrappers. Offprint from ""Fysisk Tidsskrift, 19"" (1921). Light miscolouring to extremities, lower outer corner of front wrapper bended, otherwise nice and clean. (2), 70 pp.‎

‎First seperate edition of a lecture delivered by Bohr before the Physical Society of Copenhagen on October 18, 1921. In this lecture Bohr attacked the problem of atomic constitution by asking the question: ""How may an atom be formed by the successive capture of the electrons one by one in the field of force surrounding the nucleus?"" The answers are found primarly from an analysis of the observed spectra with quidance from the chemical properties and the correspondance principle. (Collected Works, vol. 4, pp.20). The lecture was quickly translated into German and published in 'Zeitschrift für Physik'‎

Référence libraire : 61578

‎"BOHR, NIELS.‎

‎Atomteori og Naturbeskrivelse. 3 Artikler med en indledende Oversigt. - [PRESENTATION-COPY]‎

‎Copenhagen, Bianco Lunas, 1929. Royal 8vo. Original printed wrappers. Torn at top of front wrapper, no loss. Small loss to capitals. Tear to top of title-page, causing loss of ab. 1x1 cm, but not to the inscription, nor to lettering. The tear goes through the first part of the inscription, but there is no loss of any of it. 76 pp.‎

‎"BOHR, NIELS.‎

‎Atomteorien og Grundprincpperne for Naturbeskrivelsn.‎

‎København, 1930. Orig. bogtrykte omslag. 12 pp. Særtryk af Fysisk Tidsskrift.‎

‎First edition. Offprint from ""Fysisk Tidsskrift"".‎

Référence libraire : 39221

‎"BOHR, NIELS.‎

‎Determination of the Surface-Tension of Water by the Method of Jet Vibration. Offprint from: Philosophical Transactions of the Royal Society of London, Series A, Vol. 209. pp. 281-317. - [BOHR'S FIRST PUBLISHED PAPER - PRESENTATION COPY]‎

‎London, Harrison & Sons, 1909 Large4to. Original printed wrappers. Offprint from: ""Philosophical Transactions of the Royal Society of London, Series A, Vol. 209. pp. 281-317."" With cloth backstrip and I small nick to upper and lower corner of front wrapper. A fine and clean copy. Pp. 281-317.‎

‎Scarce first edition, off-print issue, of Bohr's first published paper, constituting his only ever work in experimental physics. ""His first research project, a precision measurement of the surface tension of water by the observation of a regularly vibrating jet, was completed in 1906, when he was still a student, and it won him the gold medal from the Academy of Sciences. It is a mature piece of work, remarkable for the care and thoroughness with which both the experimental and theoretical parts of the problem were handled."" (DSB).This Bohr's fist paper grew out of a work which Bohr did in 1906, and for which he won a gold medal from the Academy of Sciences. The subject was to experimentally investigate a method, proposed by Lord Rayleigh, for measuring the surface tension of water by the observation of a regularly vibrating jet. ""Bohr [...] included in his work essential improvements on Rayleigh's theory by taking into account the influence of the liquid's viscosity and of the ambient air, and by extending the earlier theory from infinitesimal to arbitrary large vibration amplitudes. In order to execute his experiments he had first of all to cope with one complication. The university had no physics laboratory."" (Pais, p. 101). Bohr thus constructed many of the instruments himself using his father's laboratory. """"I did the experiments completely alone alone in the physiological laboratory... it was a great amount of work"", which was technically demanding."" (Pais, p. 102). In spite of being Bohr's only ever work in experimental physics, it documents his deep understanding of the methods of experimentalists.""On 23 February 1907 the Academy notified him that he had won its gold medal. In 1908 he submitted a modified version to the Royal Society in London. It was his first and last paper on experiments he himself performed. His second publication was his last to deal with surface tension of liquids"" it was purely theoretical. Both papers were favorably referred to in later literature.The manuscript of the prize essay, never published in its original form, is preserved in the Bohr Archives. It is handwritten, by Harald Bohr [i.e. his brother]."" (Pais, p. 102), Rosenfeld, Bohr Bibliography No. 1. Rosenfeld, Dictionary of Scientific Biography II, pp. 239. Pais, Niels Bohr's Times, pp. 101-02.‎

Référence libraire : 54014

‎"BOHR, NIELS.‎

‎Drei Aufsätze über Spektren and Atombau. Mit sieben Abbildungen.‎

‎Braunschw., 1922. Orig.printed wrappers. VIII,148 pp.‎

‎First edition in bookform of ""Ueber die Wasser stoffspektrum"", ""Ueber die Serienspektren der Elemente"", ""der Bau der Atome und die physikalischen und chemischen Eigenschaften der Elemente"" - Rosenfeldt:24.‎

Référence libraire : 1454

‎"BOHR, NIELS.‎

‎Les Spectres et la Structure de L'Atome Trois Conferences. Traduit sur le Manuscrit de l'Auteur par A. Corvisy.‎

‎Paris, Libraire Scientifique, 1923. 8vo. Uncut in orig. printed wrappers. Tears to backstrip but preserved. A small nick to upper left corner of frontwrapper.‎

‎First French editions of the three famous papers: ""Ueber die Wasser stoffspektrum"", ""Ueber die Serienspektren der Elemente"", ""Der Bau der Atome und die physikalischen und chemischen Eigenschaften der Elemente"" - Rosenfeld:24.‎

Référence libraire : 40621

‎"BOHR, NIELS.‎

‎Linienspektren und Atombau.‎

‎Leipzig, Johann Ambrosius Barth, 1923. Contemp. full buckram. In: ""Annalen der Physik"", Vierte Folge, band 71. Stamp on verso of titlepage. Portrait as frontisp. (2),605,VI pp. (Entire volume offered). Bohr's paper: pp. 228-288 and 8 plates (on 2 leaves). Punched with cords in inner margins. Clean and fine.‎

‎First appearance of the only part of Bohr's planned new comprehensive treatise on atomic structure, announcing that this was 'the first of a series of essays....on atomic structure'.‎

Référence libraire : 48026

‎"BOHR, NIELS.‎

‎On the Quantum Theory of Line-Spectra, Part I - III. - [BOHR'S CORRESPONDENCE PRINCIPLE]‎

‎København, Bianco Lunos Bogtrykkeri, 1918 - 1922. 4to. Uncut unopened in the original printed wrappers. In ""D. Kgl. Danske Vidensk. Selsk. Skrifter, afd., 8, række IV, 1-3"" / ""Mémoires de l'Académie Royale des Sciences et des Lettres de Danemark"". Wrapper with a few minor nicks and tears but otherwise a very fine and clean copy. 118 pp.‎

‎Collected offprint-edition of Bohr's seminal work ""On the Quantum Theory of the Line-Spectra"", marking the beginning of the quantum revolution in physics, introduced the concept of quantized energy levels, provided an explanation for the observed line spectra, and served as a foundational model that inspired further developments in quantum mechanics. It is conseidered one of Bohr's most important papers and the basis for his Nobel Prize. These papers give the first clear formulation of his 'correspondence principle' establishing the limit agreement of quantum and classical physics. ""By 1918 Bohr had visualized, at least in outline, the whole theory of atomic phenomena. ... He of course realized that he was still very far from a logically consistent framework wide enough to incorporate both the quantum postulates and those aspects of classical mechanics and electrodynamics that seemed to retain some validity. Nevertheless, he at once started writing up a synthetic exposition of his arguments and of all the evidence upon which they could have any bearing" in testing how well he could summarize what was known, he found occasion to check the soundness of his ideas and to improve their formulation. In the present case, however, he could hardly keep pace with the growth of the subject the paper he had in mind at the beginning developed into a four-part treatise, 'On the Theory of Line Spectra', publication of which dragged over four years without being completed" the first three parts appeared between 1918 and 1922, and the fourth, unfortunately, was never published. Thus, the full impact of Bohr's view remained confined to the small but brilliant circle of his disciples, who indeed managed better than their master to make them more widely known by the prompter publication of their own results"" (D.S.B. 2: 246-47).‎

Référence libraire : 60501

‎"BOHR, NIELS.‎

‎On the Quantum Theory of Line-Spectra. Part I-II. [Off-print from ""D. Kgl. Danske Vidensk. Selsk. Skrifter"". - [BOHR'S CORRESPONDENCE PRINCIPLE - PRESENTATION-COPIES]‎

‎Copenhagen, Bianco Lunos, 1918. 4to. Both parts uncut and in the original printed wrappers. Wrappers detached and with small nicks and tears to extremities. Internally fine and clean. Part I unopened. 36 pp. + pp. (37) - 100.‎

‎First editions, author's off-prints (with ""Separate Copy"" printed to front wrappers), presentation-copies, of the first two parts of Bohr's seminal work ""On the Quantum Theory of the Line-Spectra"" (which appeared in three parts and which was never finished, the third part of which, published 4 years later, is almost never found in presentation-sets), in which Bohr gave his first clear presentation of his groundbreaking ""correspondence principle"": ""Which would play a pivotal role in the later development of atomic theory and its transformation into quantum mechanics."" (Kragh, Quantum Generations, p. 56). It eventually became a cornerstone in the quantum mechanics formulated by Heisenberg and Schrödinger. ""There was rarely in the history of physics a comprehensive theory which owed so much to one principle as quantum mechanics owed to Bohr's correspondence principle"" (Jammer 1966, p. 118). The evolution of quantum theory is divided into two distinct periods"" from 1900 to 1925, usually referred to as the period with the old quantum theory still grounded in classical physics and the second period with quantum mechanics from 1925 onwards. The general rules of quantum mechanics are very successful in describing objects on an atomic level. But macroscopic systems are accurately described by classical theories like classical mechanics and classical electrodynamics. If quantum mechanics were to be applicable to macroscopic objects, there must be some limit in which quantum mechanics reduces to classical mechanics. Bohr's correspondence principle demands that classical physics and quantum physics give the same answer when the systems become large. ""A major tool he developed for dealing with quantum problem, [...], was the correspondence principle, which establishes links between predictions of the classical theory and expectations for the quantum theory."" (Pais, Niels Bohr's Times, p. 20.). In this sense, the correspondence principle is not only an exceedingly important methodological principle, it also represents the transition to quantum mechanics and modern physics in general and it became the cornerstone of Bohr's philosophical interpretation of quantum mechanics which later would be closely tied to his thesis of complementarity and to the Copenhagen interpretation. Another version of the correspondence principle lives on in philosophical literature where it has taken form as a more general concept representing a development of new scientific theories.""By 1918 Bohr had visualized, at least in outline, the whole theory of atomic phenomena. ... He of course realized that he was still very far from a logically consistent framework wide enough to incorporate both the quantum postulates and those aspects of classical mechanics and electrodynamics that seemed to retain some validity. Nevertheless, he at once started writing up a synthetic exposition of his arguments and of all the evidence upon which they could have any bearing" in testing how well he could summarize what was known, he found occasion to check the soundness of his ideas and to improve their formulation. In the present case, however, he could hardly keep pace with the growth of the subject the paper he had in mind at the beginning developed into a four-part treatise, 'On the Theory of Line Spectra', publication of which dragged over four years without being completed" the first three parts appeared between 1918 and 1922 [of which the two first from 1918 are offered here], and the fourth, unfortunately, was never published. Thus, the full impact of Bohr's view remained confined to the small but brilliant circle of his disciples, who indeed managed better than their master to make them more widely known by the prompter publication of their own results"" (D.S.B. II: 246-47).Inscribed to ""Hr. Docent D. la Cour/ Venskabeligst/ fra/ Forfatteren"" on both front wrappers. The renowned Danish physicist and meteorologist Dan la Cour (1876-1942), was the son of the great Poul la Cour (1846-1908), who is considered the ""Danish Edison"". Dan la Cour was the assistant of Niels Bohr's father, Christian Bohr, and a well known scientist. From 1903, he was head of the department of the Meteorological Institute, and from 1923 leader thereof. From 1908 he was Associate Professor at the Polytechnic College. His original scientific works are highly respected, as are his original apparati for measuring earth magnetism which are considered highly valuable. ""His original intelligence, which in many ways resemble that of his father, also bore fruit in his patenting of various inventions: the ""Pyknoprobe"", developed to quickly determine the different layers of the sea"" a use of termite in quickly heating food and drinks out in the open under unfavourable weather conditions."" (From the Danish Encyclopaedia - own translation). He wrote a number of important and esteemed works and was member of the Danish Scientific Academy as well as many prominent international scientific commissions of meteorology and geophysics (i.e. president of the International Geodetical and Geophysical Union). He was also honorary Doctor at the George Washington University. Rosenfeld, Bohr-Bibliography, 15.‎

Référence libraire : 46542

‎"BOHR, NIELS.‎

‎On the Quantum Theory of Line-Spectra. Part II, On the Hydrogen Spectrum. - [AUTHOR'S OFFPRINT - PRESENTATION-COPY]‎

‎Copenhagen, Bianco Lunos, 1918. 4to. Original printed wrappers. Lower right corner of front wrapper bent. Small closed tear to front wrapper. Spine strip renewed. Otherwise fine and clean throughtout.‎

‎First printing of the second part of Bohr's seminal work ""On the Quantum Theory of the Line-Spectra"" (which appeared in three parts and which was never finished), author's off-print (with ""Separate copy"" printed on front wrapper), presentation-copy, inscribed by Bohr: ""Hr. Professor K. Prytz / med venlig Hilsen / fra Forfatteren"".""By 1918 Bohr had visualized, at least in outline, the whole theory of atomic phenomena. ... He of course realized that he was still very far from a logically consistent framework wide enough to incorporate both the quantum postulates and those aspects of classical mechanics and electrodynamics that seemed to retain some validity. Nevertheless, he at once started writing up a synthetic exposition of his arguments and of all the evidence upon which they could have any bearing" in testing how well he could summarize what was known, he found occasion to check the soundness of his ideas and to improve their formulation. In the present case, however, he could hardly keep pace with the growth of the subject the paper he had in mind at the beginning developed into a four-part treatise, 'On the Theory of Line Spectra', publication of which dragged over four years without being completed" the first three parts appeared between 1918 and 1922 [of which the second from 1918 is offered here], and the fourth, unfortunately, was never published. Thus, the full impact of Bohr's view remained confined to the small but brilliant circle of his disciples, who indeed managed better than their master to make them more widely known by the prompter publication of their own results"" (D.S.B. 2: 246-47).The present second part deals with the hydrogen spectrum, whereas the first part dealt with the general theory, and the third with the spectra of elements of higher atomic structure. Peter Kristian Prytz (1851-1929), to whom the work is inscribed, was an important physicist of the generation before Bohr. He did immense work to better the conditions of the teaching of physics at the Polytechnic Institute in Copenhagen, where Bohr studied for many years and where he later became a teacher. Prytz introduced the teaching of experimental physics here and fought for more space, more apparatus, more money for teaching assistance and more time for teaching. Thus, he played a great role in the physics-environment in Copenhagen both during Bohr's years as a student and as a teacher.Most importantly, it was Prytz who (in 1907) attracted the necessary money for the institute which enabled him to create the physical laboratory that constituted the foundation of Danish experimental physics, the field of which Bohr became professor in 1916 (till 1920 - the years during which he was working on the ""On the Quantum Theory of the Line Spectra"").Rosenfeld, Bohr-Bibliography, 15.‎

Référence libraire : 35773

‎"BOHR, NIELS.‎

‎On the Theory of Decrease of Velocity of Moving Electrified Particles on passing through Matter - [THE FOUNDATION OF BOHR'S ATOMIC THEORY]‎

‎London, Taylor & Francis, 1913. 8vo. Bound in one nice contemporary half calf binding with gilt leather title-label to spine. Published in ""The London, Edinburgh, and Dublin Philosophical Magazine and Journal of Science"", Vol. 25. No. 145-150 offered. Small repair to spine and blind stamped to lower part of title page. The Bohr papers: pp. 10-31. [Entire volume: VIII, 876 pp.+ 10 plates].‎

‎Bohr's seminal first work on nuclear physics, being the work that lays the foundation for his atomic theory (published before his ""On the Constitution of Atoms and Molecules""), in which he is able to conclude ""that a hydrogen atom contains only 1 electron outside the positively charged nucleus, and that a helium atom only contains 2 electrons outside the nucleus ."" ""Bohr's 1913 paper on alpha-particles [i.e. the present], which he had begun in Manchester, and which had led him to the question of atomic structure, marks the transition to his great work, also of 1913, on that same problem. While still in Manchester, he had already begun an early sketch of those entirely new ideas."" (Pais, p. 128). The present work must be considered one of the most important to the birth of modern atomic theory.After finishing his studies in Copenhagen, Bohr went to Cambridge in order to pursue his studies on electron theory under the guidance of J.J. Thompson. Thompson, who was beginning to lose interest in the subject by now, did, however, not recognize the genious of the young Bohr, and as soon as he could, Bohr went to Manchester, where Ernest Rutherford had established a laboratory. ""There, from March to July 1912, working with utmost concentration, he [i.e. Bohr] laid the foundation for his greatest achievements in physics, the theory of the atomic constitution."" (DSB). Bohr's survey of the implications of Rutherford's atomic model had led him to attack the much harder problem which lay at the core of it, namely determining the exact nature of the relation between the atomic number and the number of electrons in the atom. ""Bohr obtained a much deeper insight into the problem by a brilliant piece of work, which he - working, as he said, ""day and night"" - completed with astonishing speed"" (DSB), that paper being the present ""On the Theory of the Decrease of Velocity of Moving electrified Particles on passing through Matter"", which thus constitutes his very first publication on the subject, published immediately after this dense period of 1912, in the Philosophical Magazine of January 1913. ""The problem was one of immediate interest for Rutherford's laboratory: in their passage through a material medium, alpha particles continually lose energy by ionizing the atoms they encounter, at a rate depending on their velocity. Their energy loss limits the depth to which the particles can penetrate into the medium, and the relation between this depth, or range, and the velocity offers a way of determining this velocity. What Bohr did was to analyze the ionizing process on the basis of the Rutherford model of the atom and thus express the rate of energy loss in terms of the velocity by a much more accurate formula than had so far been achieved-a formula, in fact, to which modern quantum mechanics adds only nonessential refinements"" (DSB). In the present work, Bohr was thus able to conclude: ""In this paper the theory of the decrease of velocity of moving electrified particles in passing through matter is given in a form, such that the rate of the decrease in the velocity depends on the frequency of vibration of the electrons in the atoms of the absorbing material."" as well as the seminal words that have been formative for the birth of the modern atomic theory: ""Adopting Prof. Rutherford's theory of the constitution of atoms, it seems that it can be concluded with great certainty, from the absorption of alpha-rays, that a hydrogen atom contains only 1 electron outside the positively charged nucleus, and that a helium atom only contains 2 electrons outside the nucleus "". Bohr continues: ""These questions and some further information about the constitution of atoms which may be got from experiments on the absorption of alpha-rays, will be discussed in more detail in a later paper."" (pp. 30-31 of the original paper) - the last sentence referring directly to his three part ""On the Constitution of Atoms and Molecules"", in which he went on to present his postulates of the orbital structure of the electrons and their quantized radiation. Rosenfeld, Bohr Bibliography No. 5. Rosenfeld, Dictionary of Scientific Biography II, pp. 240-41. Pais, Niels Bohr's Times, pp. 117-31.‎

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‎"BOHR, NIELS.‎

‎Original photography.‎

‎""Geneva / 12-15. Februar 1952"". 17 x 11,7 cm. A stamp on the back stating: ""Copyright / URS G. ARNI / REPORTER-PHOTOGRAPHIE / 15, R. CHARLES-GIRON TÉL 2.37.55 / GENÈVE"". In pencil: ""Nils Bohr / atomphysikkonferens / Geneva / 12-15. Februari 1952"". The photo depicts an elderly Bohr with a briefcase under his arm in white shirt, tie and three piece suit.‎

‎The picture shows Bohr participating in what would become one of the most important physic conferences in the second half of the 20th century. Here CERN, the European Organization for Nuclear Research, was established. Niels Bohr had been one of the central figures in the development of atomic theory in the early 20th century and was the father to the exceedingly important Copenhagen Interpretation. These merits made him the head of the theoretical division of CERN which was located in Copenhagen. ""In Geneva the representatives of 12 European governments signed the convention setting up the interim organization, which came into being on 15 February 1952 with the title of ""European Council for Nuclear Research"", called ""CERN"" for short after the initials of the French title. Belgium, Denmark, France, the German Federal Republic, Greece, Italy, the Netherlands, Norway, Sweden, Switzerland and Yugoslavia were then provisionally united to carry out nuclear research. During the whole lifetime of the interim CERN, the United Kingdom remained simply an observer, although the interest shown in the project by that country soon took the shape of new ideas, the provision of consultants and gifts."" (CERN COURIER).‎

Référence libraire : 45018