Significance
ampere current hypothesis molecules of great importance, on the one hand, that the magnet and the magnet, and the magnet current, current and the current, and the current all these magnet magnetic interaction attributed to the role of current and the current, the establishment of ampere's law, creating the electric and magnetic linking magnetic interaction theory; on the other hand, the molecular model to replace the current magnetic charge model, reveals the substance of polarization and magnetization fundamentally internal relations, because the current is nothing more than some kind of molecules moving charge.
Development
Ampere molecular current hypothesis can not be confirmed in the case of the structure of matter little knowledge at that time, and it comes with considerable speculation ingredients; today have learned from the substance molecules, composed of atoms and molecules, atoms, electrons around the nucleus has motion, from the viewpoint of modern, "molecular current" is the nucleus consists of the orbital motion around the atomic electrons, and the spinning motion of each electron nucleus spin motion constituted. Ampere molecular current hypothesis thus have real content, it has become an important basis for understanding the magnetic material.
form ── "molecular currents" thought of "Trilogy"
Throughout the history of physics books and related papers on "molecular current" ideological and formation, though, or more or less been discussed, but the lack of a clear clue. I believe that the formation of amps thought "molecular currents" experienced three leap in understanding, although apart each time not long, but it is a step to a higher level, or "trilogy."
and other scientists compared amps have a notable feature that is extremely sensitive in science, the most acceptable outcome of others. This decision is a valuable quality amps and not someone else made a "molecular current hypothesis."
1820 In early September, the French physicist Arago (Framcois4rago, 1786 ~ 1853) from Switzerland back to the Danish physicist Oster (HansChristianOersted, 1777 ~ 1851) found that the magnetic effect of current news immediately aroused great repercussions in the French scientific community. Ampere has given this extraordinary response, he repeated the next day in Oster current experiments on the role of the needle. During the experiment, Ampere gradually realized, is not an isolated phenomenon of magnetic and electric separate, but one aspect of the many features of the electricity, as he tried to explain electromagnetic phenomena have been found from the electrical point of view. A week later, ie on September 18 he submitted to the French Academy of Sciences, the first paper reported he repeated Oster experiment results, the first step in the formation of molecular he thought the current proposed: the current round has played the magnet effect possibilities.
Next, amps creatively developed the content of the experiment, to study the interaction between the current and the current, which Biaosite experiment has greatly step forward September 25 he submitted to the French Academy of Sciences the second paper, he describes the experiment proved two straight parallel conductors, when the current direction at the same time attract each other in the opposite direction when the current report on mutually exclusive. After carrying wires he used a variety of curve shapes, study the interaction between them, and on October 9 submitted a third paper, took a second step of forming a molecular current idea, put forward: magnet a rotating about the presence of macroscopic currents magnetic axis.
amps in his paper, said: "to consider, and the interaction of two magnetic interaction between a current and a magnet, we will find that in both cases will be subject to the same laws that govern As long as the upper surface of the magnet provided to the other electrode from a straight line drawn on the source that have established a current in a plane perpendicular to the magnetic axis (rotation). on reflection of all the facts, we can not simply such current then suspected around the magnetic axis. "
" Thus, the results produced a peek, i.e. magnetic phenomena uniquely determined by the power, and in addition to the two poles of a magnet thereof with respect to the current configuration of the outer magnets, there is no difference, the magnetic south pole on the right side of these currents, the magnetic north pole at their left. "
The ampere is a molecule commentators, assuming that the current macroeconomic his existence to his magnet is based on Volta (AlessandroVolta, 1745 ~ 1827) electrical schematic heap simply explained. He believes voltaic cell is able to produce current, because the results of different metal contact. Similarly, the contact of the magnet iron molecule will generate a current. That it is seen as a series of magnets voltaic pile, which currents flow in concentric circles around the shaft for movement of the magnet.
Fresnel (AngustinJeanFresnel, 1788 ~ 1827) is a good friend of Ampere, he later learned amps paper points out amps this assumption can not be established that the magnet can not exist as envisaged in the macro-ampere otherwise, due to the presence of macroscopic currents will heat magnet, but the magnet can not actually own the hotter than the surrounding environment of some. In a letter to the Fresnel Ampere's suggestion, why not assume that the current macro-changed surrounds each molecule of it? Thus, if these molecules can be lined up, these currents will concentric current required for the synthesis microscopic. After
received a letter from the Fresnel, Ampere immediately abandoned the original assumption and took a Fresnel advice, before and after January 1821, took the third step of the molecular current thinking: put forward the famous "molecular current hypothesis" and thus within the scope of classical physics profoundly reflects the nature of magnetic objects.
Ampere his interpretation of "molecular current hypothesis" is inside the object per molecule and two kinds of current quality etheric decomposition, a current is generated around the circular molecule, a small magnet is formed; when the external magnetic field effects when they are in a regular arrangement, it is an object presents a macroscopic magnetism.
formThus, the "molecular currents" thought experienced a "possibility", "current macro" and "molecular currents" in three stages, in line with people's elementary distributed, by the phenomenon to the nature of cognitive processes. "Molecular current hypothesis" put forward by the amps, and also his unique scientific quality inseparable. Recalling amps live years, especially after the Aust discovered the magnetic effect of current, many scientists are engaged in research on the links between electricity and magnetism, such as: British Faraday (MichaelFaraday, 1791 ~ 1867) France Biot (JeanBaptisteBiot, 1774 ~ 1862) and Germany Seebeck (ThomasJohannSeebeck, 1770 ~ 1831) and so on. They are by no means ordinary, if not timely amps and development Oster repeated experiments, if not immediately accept the Fresnel Ampere's suggestion that if the amps do not have extremely sensitive in science, the most acceptable outcome to others unique qualities, perhaps "molecular current hypothesis," the authors of the will changed hands.
"Molecular current hypothesis" proposed initial Debate
in accordance with the foregoing explanation of amperes "molecular current hypothesis", is the unacceptable. On this issue, amps was ahead of the times. Because at the time, people do not understand the structure of atoms, molecules and therefore can not explain how the current internal material formed. After until 1911, Rutherford (EnrstRutherford, 1871 ~ 1937) analysis and calculation of α scattering experiment, all atoms have proposed as a model core rotating around "cores, such as electronic planet, only the orbital moment concept. in 1922 Stern (OttOSteen1888 ~ 1969) and Gerlach (W.Grelach) with silver atoms successfully done later named Hinako to their experiments and found that there is a track magnetic atoms that can ` magnetic moment moment to explain the order to explain this issue, Uhlenbeck (GeorgeEugeneUhlenbeck, 1900 ~) and high-Des Mitt (SamnelAbrahamGondsmit, 1902 ~ 1978) have made assumptions about the electron spin in 1925, successfully Stern explains the results ── Gerlach experiment. today we know that it is the movement of electrons within these microscopic particles of atoms, molecules form a "molecular currents." but we can not use the same physical development after decades of level to require amps, otherwise it is too harsh,
"molecular current hypothesis" put forward in the future, amps, although no further explanation, but he was on his belief is very strong. he has inspired and Arago is recommended as the solenoid is energized with a magnetized needle in which the experiment. in the September 25, 1820, Arago reported the results of the experiment to the French Academy of Sciences and the success of the experiment is the nature of the magnetic amps of electricity thought to be strengthened. in 1821, he replied in Dutch physicist Van Baker (VanBeck) in a letter insisting that this hypothesis can not only be used to explain magnetic phenomena, but also can be used to explain the chemical compounds and chemical affinity. the latter has become his doctrine could not be immediately and an important cause of universally accepted because accepting this doctrine means to accept a new theory about the structure of matter. molecule was coupled with the current model as if covered with a layer of mist so that people can not see it. so "molecular current hypothesis" Although profoundly reflects the nature of the object of magnetic, but it was rejected at that time most physicists.
Out of "molecular current hypothesis" challenge . physicists, the most typical is probably to the number of Faraday 1822, he designed an experiment: wrapped with insulated wire, made solenoid on a glass, half immersed in water and then horizontally in the water. floating a long needle according amperes view, corresponding to an end of the solenoid magnetic south pole, and the other end corresponding to the magnetic north pole, south pole pointing to the needle if the solenoid Arctic, will be attracted to the north pole and the solenoid stopped at the end of the Arctic. Faraday pointed out that this does not match with the experimental results of his experiments needle Antarctica continues through the solenoid, solenoid until near the south Pole. Faraday argued that if the needle is unipolar, it We will continue endlessly move along magnetic field lines. Faraday considered, and a carrier corresponding to the solenoid magnet is not solid, but rather is a cylindrical magnet.
amps retorted, a cylindrical magnet And solenoids are not the same. Current hypothesis according to its molecule, the current cylindrical magnet is a small circle in a small circle alone, and the current in the solenoid along the great circle. To demonstrate the cylindrical magnet currents cancel each other, he made a public presentation:
The insulated wire wound a plurality of turns, the coil is made. Placed inside the coil by a ring made of thin copper sheet, taking a ring magnet disposed in the vicinity, if there are copper rings macroscopic currents, magnetic drives copper ring will deflect. Otherwise, there can be only molecular current. Ampere's experiments show that the copper ring, only molecular current.
Ampere later with ferromagnetic horseshoe above experiment was repeated, found deflection copper rings. But he put out experiments in induced current macro-molecular trying to also be interpreted as the result of current action. This idea amps until 1825 to Herschel (JohnHerschel, 1793 ~ 1871) is still sticking to the letter, he said in the letter: "The phenomenon is caused by a current or magnet for small current generated." Although Ampere It does not say that these small molecules current is current, but the current number of molecules having the same size as the current level. This suggests that the molecular ampere current thinking is very firm. Unfortunately, he attributed his induction current molecular current, do not accept the induced current alone. He admitted that if the induced current, then his theory of molecular current hypothesis on almost deprived of. Otherwise, there is the phenomenon of electromagnetic induction may be brought forward seven or eight years is amps rather than Faraday discovered.
amperes during "molecular current hypothesis" established in the academic debate also occurred between amperes Biot. For the debate, the physical historians who each have their own views on this, but one thing is the same, that this debate makes amps more clearly see the need to simplify the magnetic current, but also to his "molecular current hypothesis "becomes more clear up.
German physicist Seebeck also oppose amps molecular current hypothesis, he believes that something more fundamental is the magnetic current is the result of the role of magnetic.
Until then, the idea was Ampere Newman (F.E.Neumann, 1798 ~ 1895) and Weber (WilhelmEduardWeber, 1804 ~ 1891) accepted and promoted in the 1840s and developed into their electrodynamics.
After"molecular current hypothesis" put forward, experienced a "very clear", "rejected" to "increasingly clear" that form the basis of several stages of development electrodynamics, which also tells us that science the findings, scientific theories and acceptance of scientific results, not all plain sailing, but beneficial academic debate can contribute to the development of science.