On the Machian Origin of Inertia

We examine Sciama's inertia theory: we generalise it, by combining rotation and expansion in one unique model, we find the angular speed of the Universe, and we stress that the theory is zero-total-energy valued. We compare with other theories of the same null energy background. We determine the numerical value of a constant which appears in the Machian inertial force expression devised by Graneau and Graneau[2], by introducing the above angular speed. We point out that this last theory is not restricted to Newtonian physics as those authors stated but is, in fact, compatible with other cosmological and gravitational theories. An argument by Berry[7] is shown in order to "derive" Brans-Dicke relation in the present context.Comment: 10 pages including front one. New version was accepted to publication by Astrophysics and Space Scienc

Influence of qubit displacements on quantum logic operations in a silicon-based quantum computer with constant interaction

The errors caused by qubit displacements from their prescribed locations in an ensemble of spin chains are estimated analytically and calculated numerically for a quantum computer based on phosphorus donors in silicon. We show that it is possible to polarize (initialize) the nuclear spins even with displaced qubits by using Controlled NOT gates between the electron and nuclear spins of the same phosphorus atom. However, a Controlled NOT gate between the displaced electron spins is implemented with large error because of the exponential dependence of exchange interaction constant on the distance between the qubits. If quantum computation is implemented on an ensemble of many spin chains, the errors can be small if the number of chains with displaced qubits is small

Non-Resonant Effects in Implementation of Quantum Shor Algorithm

We simulate Shor's algorithm on an Ising spin quantum computer. The influence of non-resonant effects is analyzed in detail. It is shown that our ``$2\pi k$''-method successfully suppresses non-resonant effects even for relatively large values of the Rabi frequency.Comment: 11 pages, 13 figure

Silicon solar cells improved by lithium doping

Results of conference on characteristics of lithium-doped silicon solar cells and techniques required for fabrication indicate that output of cells has been improved to point where cells exhibit radiation resistance superior to those currently in use, and greater control and reproducibility of cell processing have been achieved

The Agent Orange Veteran Payment Program

This thesis discusses how to enhance the public discussion of moral and political questions. Enhancing public ‘deliberation’ is desirable since it provides citizens with influence, it enables coming to an understanding, and it ensures legitimacy. The concept of ethico-political judgment, with its two conditions, is elaborated on as an ideal that suggests how we should deliberate. In order to understand how we actually deliberate, an empirical inquiry into the public discourse on prenatal diagnosis and screening in the Netherlands and Sweden is conducted. On the basis of Kant’s ethics and his theory of the faculty of judgment, the two conditions for public deliberation are developed. These conditions are the giving of and asking for normative reasons as well as aiming at impartiality of judgment. Normative reasons are prescriptive, universal, and internal and these are related to Kant’s ethics. Impartiality is related to Kant’s ‘enlarged thought’, to think from the standpoint of others, as well as Kant’s practical philosophy. We need to think from the standpoints of others in order to consider whether or not the principle of our action applies to all. Four thematic foci in the public discourse on prenatal diagnosis are investigated – the unborn life, attitudes toward the disabled, implications of new choices, and the limits of medicine. The conclusion is that – if we wish to enhance public deliberation on the basis of the two conditions of ethico-political judgment – we should deal with both interpretive differences over universal principles (such as respect for autonomy and human dignity) and varying representations of ‘the other’ (such as the fetus, disabled persons, mothers-to-be, and future parents).I denna avhandling diskuteras hur offentlig diskussion kring moraliska och politiska frågor kan intensifieras. Att intensifiera offentlig diskussion är önskvärt för att ge medborgare inflytande, för att främja förståelse och för att skapa legitimitet. Begreppet etisk-politisk bedömning utvecklas som ett ideal för hur vi bör diskutera. För att undersöka hur vi faktiskt diskuterar görs en empirisk undersökning av det offentliga samtalet om fosterdiagnostik i Nederländerna och Sverige. Med utgångspunkt i Kants etik och hans teori om omdömesförmågan utvecklas två villkor för offentlig diskussion. Dessa villkor är att ge och efterfråga normativa skäl och att sträva efter opartiskhet av omdömesförmågan. Normativa skäl är preskriptiva, universella och interna. Begreppet utvecklas utifrån Kants etik. Opartiskhet baseras på Kants ’utvidgade tänkande’: att tänka utifrån andras perspektiv. Denna idé relateras till Kants praktiska filosofi. Det ’utvidgade tänkandet’ innebär att vi tar ställning till om principen som vi väljer för en handling gäller alla. Fyra teman i det offentliga samtalet om fosterdiagnostik analyseras – det ofödda livet, attityder gentemot handikappade, implikationer av nya val och den medicinska praktikens gränser. Slutsatsen är att om vi önskar intensifiera offentlig diskussion med utgångspunkt i de två villkor som utvecklas, bör vi ta itu med tolkningsskillnader när det gäller universella principer (som respekt för autonomi och människovärde) samt olika representationer av ’den andra’ (som fostret, handikappade, gravida kvinnor och blivande föräldrar)

Creation of entanglement in a scalable spin quantum computer with long-range dipole-dipole interaction between qubits

Creation of entanglement is considered theoretically and numerically in an ensemble of spin chains with dipole-dipole interaction between the spins. The unwanted effect of the long-range dipole interaction is compensated by the optimal choice of the parameters of radio-frequency pulses implementing the protocol. The errors caused by (i) the influence of the environment,(ii) non-selective excitations, (iii) influence of different spin chains on each other, (iv) displacements of qubits from their perfect locations, and (v) fluctuations of the external magnetic field are estimated analytically and calculated numerically. For the perfectly entangled state the z component, M, of the magnetization of the whole system is equal to zero. The errors lead to a finite value of M. If the number of qubits in the system is large, M can be detected experimentally. Using the fact that M depends differently on the parameters of the system for each kind of error, varying these parameters would allow one to experimentally determine the most significant source of errors and to optimize correspondingly the quantum computer design in order to decrease the errors and M. Using our approach one can benchmark the quantum computer, decrease the errors, and prepare the quantum computer for implementation of more complex quantum algorithms.Comment: 31 page

Effects of solar proton flares on the power output of solar cells having various configurations

Solar proton flare effects on silicon photovoltaic power system for deep space mission

Stability of the Ground State of a Harmonic Oscillator in a Monochromatic Wave

Classical and quantum dynamics of a harmonic oscillator in a monochromatic wave is studied in the exact resonance and near resonance cases. This model describes, in particular, a dynamics of a cold ion trapped in a linear ion trap and interacting with two lasers fields with close frequencies. Analytically and numerically a stability of the ``classical ground state'' (CGS) -- the vicinity of the point ($x=0, p=0$) -- is analyzed. In the quantum case, the method for studying a stability of the quantum ground state (QGS) is suggested, based on the quasienergy representation. The dynamics depends on four parameters: the detuning from the resonance, $\delta=\ell-\Omega/\omega$, where $\Omega$ and $\omega$ are, respectively, the wave and the oscillator's frequencies; the positive integer (resonance) number, $\ell$; the dimensionless Planck constant, $h$, and the dimensionless wave amplitude, $\epsilon$. For $\delta=0$, the CGS and the QGS are unstable for resonance numbers $\ell=1, 2$. For small $\epsilon$, the QGS becomes more stable with increasing $\delta$ and decreasing $h$. When $\epsilon$ increases, the influence of chaos on the stability of the QGS is analyzed for different parameters of the model, $\ell$, $\delta$ and $h$.Comment: RevTeX, 38 pages, 24 figure