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Full-Text Articles in Physics
Adiabatic Invariance With First Integrals Of Motion, Artur D. Adib
Adiabatic Invariance With First Integrals Of Motion, Artur D. Adib
Dartmouth Scholarship
The construction of a microthermodynamic formalism for isolated systems based on the concept of adiabatic invariance is an old but seldom appreciated effort in the literature, dating back at least to P. Hertz [Ann. Phys. (Leipzig) 33, 225 (1910)]. An apparently independent extension of such formalism for systems bearing additional first integrals of motion was recently proposed by Hans H. Rugh [Phys. Rev. E 64, 055101 (2001)], establishing the concept of adiabatic invariance even in such singular cases. After some remarks in connection with the formalism pioneered by Hertz, it will be suggested that such an extension can …
Location Of Pc 1–2 Waves Relative To The Magnetopause, R E. Denton, J Labelle, X Zhu
Location Of Pc 1–2 Waves Relative To The Magnetopause, R E. Denton, J Labelle, X Zhu
Dartmouth Scholarship
Spacecraft-borne and ground-based magnetome- ters frequently detect magnetospheric micropulsations in the period range 0.2–10s, termed Pc 1–2, and attributed to electromagnetic ion cyclotron waves driven by temperature anisotropy (T⊥ > T∥). Previous surveys of Pc 1 occur- rence locations have been limited to L ≤ 9. We present AMPTE/IRM observations of the distribution of Pc 1 waves out to the magnetopause, for a limited region of MLT = 10–14. The probability of wave occurrence Pwav is large (> 0.15) between L = 7–12, peaking at L = 8–10 (Pwav ∼ 0.25). When the L-value is normalized to the magnetopause position Lmp, …
Higher-Order Evaluation Of The Critical Temperature For Interacting Homogeneous Dilute Bose Gases, Frederico F. F. De Souza Cruz, Marcus Pinto, Rudnei O. Ramos, Paulo Sena
Higher-Order Evaluation Of The Critical Temperature For Interacting Homogeneous Dilute Bose Gases, Frederico F. F. De Souza Cruz, Marcus Pinto, Rudnei O. Ramos, Paulo Sena
Dartmouth Scholarship
We use the nonperturbative linear δ expansion method to evaluate analytically the coefficients c1 and c''2 that appear in the expansion for the transition temperature for a dilute, homogeneous, three-dimensional Bose gas given by Tc=T0(1+c1an1/3+[c′2ln(an1/3)+c''2]a2n2/3+O(a3n)), where T0 is the result for an ideal gas, a is the s-wave scattering length, and n is the number density. In a previous work the same method has been used to evaluate c1 to order δ2 with the result c1=3.06. Here, we push the calculation to the next two orders obtaining c1=2.45 at order δ3 and c1=1.48 at order δ4. Analyzing the topology …
Entanglement And Decoherence Of A Micromechanical Resonator Via Coupling To A Cooper-Pair Box, A. D. Armour, M. P. Blencowe, K. C. Schwab
Entanglement And Decoherence Of A Micromechanical Resonator Via Coupling To A Cooper-Pair Box, A. D. Armour, M. P. Blencowe, K. C. Schwab
Dartmouth Scholarship
We analyze the quantum dynamics of a micromechanical resonator capacitively coupled to a Cooper-pair box. With appropriate quantum state control of the Cooper box, the resonator can be driven into a superposition of spatially separated states. The Cooper box can also be used to probe the decay of the resonator superposition state due to environmental decoherence.
Nonperturbative Effects In A Rapidly Expanding Quark Gluon Plasma, A. K. Mohanty, P. Shukla, Marcelo Gleiser
Nonperturbative Effects In A Rapidly Expanding Quark Gluon Plasma, A. K. Mohanty, P. Shukla, Marcelo Gleiser
Dartmouth Scholarship
Within first-order phase transitions, we investigate pretransitional effects due to the nonperturbative, large-amplitude thermal fluctuations which can promote phase mixing before the critical temperature is reached from above. In contrast with the cosmological quark-hadron transition, we find that the rapid cooling typical of the relativistic heavy ion collider and large hadron collider experiments and the fact that the quark-gluon plasma is chemically unsaturated suppress the role of nonperturbative effects at current collider energies. Significant supercooling is possible in a (nearly) homogeneous state of quark gluon plasma.
Mutually Unbiased Binary Observable Sets On N Qubits, Jay Lawrence, Časlav Brukner, Anton Zeilinger
Mutually Unbiased Binary Observable Sets On N Qubits, Jay Lawrence, Časlav Brukner, Anton Zeilinger
Dartmouth Scholarship
The Pauli operators (tensor products of Pauli matrices) provide a complete basis of operators on the Hilbert space of N qubits. We prove that the set of 4N−1 Pauli operators may be partitioned into 2N+1 distinct subsets, each consisting of 2N−1 internally commuting observables. Furthermore, each such partitioning defines a unique choice of 2N+1 mutually unbiased basis sets in the N-qubit Hilbert space. Examples for 2 and 3 qubit systems are discussed with emphasis on the nature and amount of entanglement that occurs within these basis sets.
Nonequilibrium Precursor Model For The Onset Of Percolation In A Two-Phase System, Marcelo Gleiser, Rafael C. Howell, Rudnei O. Ramos
Nonequilibrium Precursor Model For The Onset Of Percolation In A Two-Phase System, Marcelo Gleiser, Rafael C. Howell, Rudnei O. Ramos
Dartmouth Scholarship
Using a Boltzmann-like equation, we investigate the nonequilibrium dynamics of nonperturbative fluctuations within the context of Ginzburg-Landau models. As an illustration, we examine how a two-phase system initially prepared in a homogeneous, low-temperature phase becomes populated by precursors of the opposite phase as the temperature is increased. We compute the critical value of the order parameter for the onset of percolation, which signals the breakdown of the conventional dilute gas approximation.