scholarly journals The passage of neutrons through matter

1932 ◽  
Vol 138 (835) ◽  
pp. 460-469 ◽  
Keyword(s):  
Quantum Theory ◽  
Charged Particle ◽  
Hydrogen Atom ◽  
Experimental Method ◽  
Nuclear Structure ◽  
Quantum State ◽  
Mathematical Description ◽  
Elastic Collisions ◽  
Satisfactory Theory

The discovery of the neutron by Chadwick is of very great importance to the theory of nuclear structure for it is apparently a much simpler unit than the α-particle and so more amenable to mathematical description. It is, therefore, very necessary to obtain as much knowledge as possible of the field of force surrounding the particle. If this field be known a very strict test of any theory of the nature of the particle is provided. The experimental method used to determine the field of force consists in the observation of the collisions of neutrons with material particles such as electrons and protons. The interpretation of these results requires the development of a satisfactory theory of such collisions. Fortunately, in most cases the smallness of the field of interaction between a neutron and a charged particle leads to the possibility of applying the simple approximate quantum theory of collisions due to Born. In this paper we will discuss the application of the theory to the elastic collisions of neutrons with material particles. A neutron model consisting of a hydrogen atom in a nearly zero quantum state will be considered in particular and the probability of disintegration of such a model by nuclear impact estimated. It will be shown that the available experimental material indicates that the radius of such an atom must be less than 2·0 × 10 -13 cm.

Probability and Explanation

2017 ◽  
Author(s):  
Richard Healey
Keyword(s):  
Quantum Theory ◽  
Quantum State ◽  
Causal Explanation ◽  
Born Rule ◽  
Correct Application

We can use quantum theory to explain an enormous variety of phenomena by showing why they were to be expected and what they depend on. These explanations of probabilistic phenomena involve applications of the Born rule: to accept quantum theory is to let relevant Born probabilities guide one’s credences about presently inaccessible events. We use quantum theory to explain a probabilistic phenomenon by showing how its probabilities follow from a correct application of the Born rule, thereby exhibiting the phenomenon’s dependence on the quantum state to be assigned in circumstances of that type. This is not a causal explanation since a probabilistic phenomenon is not constituted by events that may manifest it: but each of those events does depend causally on events that actually occur in those circumstances. Born probabilities are objective and sui generis, but not all Born probabilities are chances.

Entanglement

2017 ◽  
Author(s):  
Richard Healey
Keyword(s):  
Quantum Theory ◽  
Quantum State ◽  
Physical Condition ◽  
Physical System ◽  
Polarization State ◽  
Quantum Systems ◽  
Ghz State ◽  
Mathematical Representation ◽  
Entangled State ◽  
Physical Relation

Often a pair of quantum systems may be represented mathematically (by a vector) in a way each system alone cannot: the mathematical representation of the pair is said to be non-separable: Schrödinger called this feature of quantum theory entanglement. It would reflect a physical relation between a pair of systems only if a system’s mathematical representation were to describe its physical condition. Einstein and colleagues used an entangled state to argue that its quantum state does not completely describe the physical condition of a system to which it is assigned. A single physical system may be assigned a non-separable quantum state, as may a large number of systems, including electrons, photons, and ions. The GHZ state is an example of an entangled polarization state that may be assigned to three photons.

TOPOLOGICAL QUANTIZATION OF THE MAGNETIC FLUX

2000 ◽  
Vol 15 (24) ◽  
pp. 1491-1495 ◽  
Author(s):  
DANIEL WISNIVESKY
Keyword(s):  
Quantum Theory ◽  
Charged Particle ◽  
Magnetic Flux ◽  
Linear Group ◽  
Connected Region ◽  
Magnetic Tube ◽  
Dirac Monopole ◽  
Multiply Connected ◽  
Quantum Problem ◽  
Multiply Connected Region

We discuss the quantum problem of a charged particle in a multiply connected region encircling a magnetic tube, using a theory in which space and internal coordinates are derived from the parameters of a linear group of transformations (group space quantum theory). Based only on symmetry considerations, we show that, the magnetic flux in the tube must be quantized in multiples of the Dirac monopole charge.

scholarly journals The orbits of a charged particle round an electric and magnetic nucleus

1915 ◽  
Vol 91 (628) ◽  
pp. 273-290
Keyword(s):  
Charged Particle ◽  
Hydrogen Atom ◽  
Magnetic Moment ◽  
Equatorial Plane ◽  
Central Mass ◽  
Magnetic Nucleus ◽  
Chief Interest ◽  
Revolving Body ◽  
Charged Nucleus ◽  
Positively Charged

The following communication is formally a complement to one published in the 'Proceedings' of the Society on "The Effect of the Magneton on the Scattering of α-Rays." In the present paper the more general case of a central positively charged nucleus possessing mass and a magnetic moment is considered. The case is treated as if the mass of the nucleus is so large compared with that of the revolving particle that it may be regarded as fixed. It is, therefore, not directly applicable when the revolving body is an α-particle except in cases where the central mass is large compared with that of the hydrogen atom. It is shown later what modification is needed when the motion of the nucleus is not large enough to affect its magnetic quality. The former paper was suggested by certain theories relating to the scattering of α and β-particles by matter. In the present, however, the chief interest lies in the discussion of the nature and properties of the various orbits, more especially of such as do not extend to infinity, or as they may be called "local orbits." In both cases the motion in the equatorial plane of the magneton alone is considered.

Losing Sight of the Forest for the ψ‎

2020 ◽  
pp. 185-211
Author(s):  
Alisa Bokulich
Keyword(s):  
Quantum Theory ◽  
Quantum State ◽  
Configuration Space ◽  
Mathematical Formalism ◽  
Alternative Formulation ◽  
Quantum Hydrodynamics ◽  
Many Body ◽  
Quantum Realism ◽  
The World ◽  
The Many

Traditionally \1 is used to stand for both the mathematical wavefunction (the representation) and the quantum state (thing in the world). This elision has been elevated to a metaphysical thesis by advocates of wavefunction realism. The aim of Chapter 10 is to challenge the hegemony of the wavefunction by calling attention to a littleknown formulation of quantum theory that does not make use of the wavefunction in representing the quantum state. This approach, called Lagrangian quantum hydrodynamics (LQH), is a full alternative formulation, not an approximation scheme. A consideration of alternative formalisms is essential for any realist project that attempts to read the ontology of a theory off the mathematical formalism. The chapter shows that LQH falsifies the claim that one must represent the many-body quantum state as living in 3n-dimensional configuration space. When exploring quantum realism, regaining sight of the proverbial forest of quantum representations beyond the \1 is just the beginning.

scholarly journals Estimation of Systematic Errors for Deuteron Electric Dipole Moment Search at COSY

2016 ◽  
Vol 40 ◽  
pp. 1660099 ◽  
Author(s):  
Stanislav Chekmenev
Keyword(s):  
Dipole Moment ◽  
Charged Particle ◽  
Experimental Method ◽  
Electric Dipole Moment ◽  
Electric Dipole ◽  
Systematic Errors ◽  
Great Level ◽  
Spin Motion ◽  
Wien Filter ◽  
Systematic Effects

An experimental method which is aimed to find a permanent EDM of a charged particle was proposed by the JEDI (Jülich Electric Dipole moment Investigations) collaboration. EDMs can be observed by their influence on spin motion. The only possible way to perform a direct measurement is to use a storage ring. For this purpose, it was decided to carry out the first precursor experiment at the Cooler Synchrotron (COSY). Since the EDM of a particle violates CP invariance it is expected to be tiny, treatment of all various sources of systematic errors should be done with a great level of precision. One should clearly understand how misalignments of the magnets affects the beam and the spin motion. It is planned to use a RF Wien filter for the precusor experiment. In this paper the simulations of the systematic effects for the RF Wien filter device method will be discussed.

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