title: Macroscopic quantum phenomena

authors: Munro, William John

subjects: Quantum theory

abstract: This thesis consists of two parts. Although both are concerned with macroscopic quantum phenomena, I choose to present the two parts quite separately.  

Macroscopic Quantum Phenomena: Tests of Quantum Mechanics 

The correctness of quantum mechanics has been verified in numerous situations. A particularly strong test of quantum mechanics was suggested by Bell, who showed that the predictions of all classical theories, based as they are on the assumptions of local realism, contradict those of quantum mechanics. Later work by Greenberger, Horne, and Zeilinger showed that the GHZ phenomena also contradicts all classical theories. Experimental tests of Bells inequality performed to date support quantum mechanics (No experimental test of the GHZ phenomenon has yet been attempted). However, such tests have been so far restricted to microscopic systems in the sense that one particle is at a detector at a time.  
Our interest here in the first part of this thesis is in tests of quantum mechanics against local realistic theories in macroscopic or mesoscopic systems where there is a significant number of particles incident on each analyser. The states considered in the first two chapters are not simple quantum superpositions of macroscopically distinct states, but we nevertheless show how one can obtain tests of quantum mechanics in situations involving large numbers of particles. A more elementary macroscopic quantum state, and one in which the deviation from classical interpretations is striking, is the Schrodinger Cat state considered by Schrodinger in his famous "Schrodinger Cat" paradox. In Chapter Three we consider a scheme for generating such a state. 

The Quantum Brownian Motion Master Equation 

The second section of this thesis involves an examination of various aspects of the Quantum Brownian Motion Master Equation. We begin with a discussion of the recent problem occurring from the study of the quantum Brownian motion (QBM) master equation, which can occur because the QBM master equation is not of the Lindblad form. We examine two specific examples, namely the damped free particle and the two level atom. More specifically, in the case of the evolution of a free particle, we show that the equation of motion for the Wigner function (which is exactly the same as the Fokker-Planck equation for classical Brownian motion) gives unphysical results if the initial position distribution is well localised. In the case of the two level atom we show that unphysical results can also occur even in the steady state. 
The last chapter of the thesis involves using the quantum Brownian motion master equation to estimate the rate of diagonalisation of the off diagonal elements of a Fermion system. These elements contain the "quantum information" and hence knowledge of how long they exist can determine the type of model required to describe the semiconductor medium. Using a very simplistic approach we can show that there are two main time scales present and for normal parameters one of these is very small. If we neglect electron-electron scattering we can show that the the many electron system solution is simply a product of the one electron solutions.

text: Macroscopic quantum phenomena This thesis consists of two parts. Although both are concerned with macroscopic quantum phenomena, I choose to present the two parts quite separately.  

Macroscopic Quantum Phenomena: Tests of Quantum Mechanics 

The correctness of quantum mechanics has been verified in numerous situations. A particularly strong test of quantum mechanics was suggested by Bell, who showed that the predictions of all classical theories, based as they are on the assumptions of local realism, contradict those of quantum mechanics. Later work by Greenberger, Horne, and Zeilinger showed that the GHZ phenomena also contradicts all classical theories. Experimental tests of Bells inequality performed to date support quantum mechanics (No experimental test of the GHZ phenomenon has yet been attempted). However, such tests have been so far restricted to microscopic systems in the sense that one particle is at a detector at a time.  
Our interest here in the first part of this thesis is in tests of quantum mechanics against local realistic theories in macroscopic or mesoscopic systems where there is a significant number of particles incident on each analyser. The states considered in the first two chapters are not simple quantum superpositions of macroscopically distinct states, but we nevertheless show how one can obtain tests of quantum mechanics in situations involving large numbers of particles. A more elementary macroscopic quantum state, and one in which the deviation from classical interpretations is striking, is the Schrodinger Cat state considered by Schrodinger in his famous "Schrodinger Cat" paradox. In Chapter Three we consider a scheme for generating such a state. 

The Quantum Brownian Motion Master Equation 

The second section of this thesis involves an examination of various aspects of the Quantum Brownian Motion Master Equation. We begin with a discussion of the recent problem occurring from the study of the quantum Brownian motion (QBM) master equation, which can occur because the QBM master equation is not of the Lindblad form. We examine two specific examples, namely the damped free particle and the two level atom. More specifically, in the case of the evolution of a free particle, we show that the equation of motion for the Wigner function (which is exactly the same as the Fokker-Planck equation for classical Brownian motion) gives unphysical results if the initial position distribution is well localised. In the case of the two level atom we show that unphysical results can also occur even in the steady state. 
The last chapter of the thesis involves using the quantum Brownian motion master equation to estimate the rate of diagonalisation of the off diagonal elements of a Fermion system. These elements contain the "quantum information" and hence knowledge of how long they exist can determine the type of model required to describe the semiconductor medium. Using a very simplistic approach we can show that there are two main time scales present and for normal parameters one of these is very small. If we neglect electron-electron scattering we can show that the the many electron system solution is simply a product of the one electron solutions.

year: 1994

title: An empirical investigation of agency costs and ownership structure in unlisted small businesses

authors: Wellalage, Nirosha Hewa

subjects: agency costs

abstract: The study uses panel data to investigate agency costs, both principal-agent (PA) and principal-principal (PP), in 240 small businesses not listed on the New Zealand Stock Exchange. Results show that both forms of agency cost vary according to industry, the life of the business and size. The results indicate that the degree of owner involvement in the business influences firm PA and PP agency costs. Moreover, this study finds non-linear relationship between agency costs and ownership structure align with convergence of interest hypothesis and managerial entrenchment hypothesis. It is noted that the distortion between equity returns and debt returns gives rise to a preference for quasi-equity and distorts the productive base and effective pricing of risk. The analysis indicates there is considerable variability in the burden of agency cost and that this raises the potential for regulatory and policy reforms that may enhance the productivity and growth in the sector.

text: An empirical investigation of agency costs and ownership structure in unlisted small businesses The study uses panel data to investigate agency costs, both principal-agent (PA) and principal-principal (PP), in 240 small businesses not listed on the New Zealand Stock Exchange. Results show that both forms of agency cost vary according to industry, the life of the business and size. The results indicate that the degree of owner involvement in the business influences firm PA and PP agency costs. Moreover, this study finds non-linear relationship between agency costs and ownership structure align with convergence of interest hypothesis and managerial entrenchment hypothesis. It is noted that the distortion between equity returns and debt returns gives rise to a preference for quasi-equity and distorts the productive base and effective pricing of risk. The analysis indicates there is considerable variability in the burden of agency cost and that this raises the potential for regulatory and policy reforms that may enhance the productivity and growth in the sector.

year: 2012

title: Te Karauna Hou: the senior Ngati Rahiri rangatira

authors: Hart, Philip

abstract: Te Karauna Hou, the principal Ngati Rahiri rangatira living at Te Aroha in 1880, had a distinguished whakapapa linking him to several hapu. Before settling permanently at Te Aroha in the 1870s he lived in several places, especially at Kaitawa, on the southern outskirts of Thames. One of the principal rangatira in Hauraki, he was loyal to the Crown during the Waikato War, and later assisted Pakeha settlement. To emphasize his mana and that of his hapu, he held big festivities at Kaitawa and at Omahu pa at Te Aroha. 
In 1871, when Ngati Haua won a (temporary) victory in the land court over the ownership of the Aroha Block, Karauna took control of it on behalf of the Marutuahu confederation, and subsequently kept Ngati Haua at bay. For a time he opposed road-making on this block, but later agreed to it, for financial reasons. Like all rangatira, he sought to maximize his ownership of as many blocks of land as possible, sometimes having his lies exposed through his contradicting his earlier evidence. He also denied receiving money for land when his denials were easily disproved. Despite leasing and selling land, selling timber and gum, and opening his land to miners, he often struggled financially.  
Karauna claimed to have found gold in Hauraki in 1852, and was willing to open his land at Thames to miners, but did not invest in any claims before the Te Aroha rush, when he attempted to extract a bonus of £1,000 from the government for opening the field. After his death in 1885, Pakeha remembered with gratitude his friendly attitude to them, but they also remembered his drunkenness, which meant he lost the respect of both Maori and Pakeha in his latter years.

text: Te Karauna Hou: the senior Ngati Rahiri rangatira Te Karauna Hou, the principal Ngati Rahiri rangatira living at Te Aroha in 1880, had a distinguished whakapapa linking him to several hapu. Before settling permanently at Te Aroha in the 1870s he lived in several places, especially at Kaitawa, on the southern outskirts of Thames. One of the principal rangatira in Hauraki, he was loyal to the Crown during the Waikato War, and later assisted Pakeha settlement. To emphasize his mana and that of his hapu, he held big festivities at Kaitawa and at Omahu pa at Te Aroha. 
In 1871, when Ngati Haua won a (temporary) victory in the land court over the ownership of the Aroha Block, Karauna took control of it on behalf of the Marutuahu confederation, and subsequently kept Ngati Haua at bay. For a time he opposed road-making on this block, but later agreed to it, for financial reasons. Like all rangatira, he sought to maximize his ownership of as many blocks of land as possible, sometimes having his lies exposed through his contradicting his earlier evidence. He also denied receiving money for land when his denials were easily disproved. Despite leasing and selling land, selling timber and gum, and opening his land to miners, he often struggled financially.  
Karauna claimed to have found gold in Hauraki in 1852, and was willing to open his land at Thames to miners, but did not invest in any claims before the Te Aroha rush, when he attempted to extract a bonus of £1,000 from the government for opening the field. After his death in 1885, Pakeha remembered with gratitude his friendly attitude to them, but they also remembered his drunkenness, which meant he lost the respect of both Maori and Pakeha in his latter years.

year: 2016