It has been repeatedly argued, most recently by Nicholas Maxwell, that the special theory of relativity is incompatible with the view that the future is in some degree undetermined; and Maxwell contends that this is a reason to reject that theory. In the present paper, an analysis is offered of the notion of indeterminateness (or “becoming”) that is uniquely appropriate to the special theory of relativity, in the light of a set of natural conditions upon such a notion; and reasons are given for regarding this conception as (not just formally consistent with relativity theory, but also) philosophically reasonable. The bearings upon Maxwell's program for quantum theory are briefly considered.
In addition to ground state wave functions and energies, excited states and their energies are also obtained in a standard Rayleigh-Ritz variational calculation. However, their accuracy is generally much lower. Using the super-symmetric (SUSY) form of quantum mechanics, we show that better accuracy and more rapid convergence can be obtained by taking advantage of calculations of the ground states of higher sector SUSY Hamiltonians, followed by application of the SUSY "charge operators". Our proof of principle study uses a general family of one-dimensional anharmonic oscillator models. We first obtain the exact, analytic ground states for a general family of anharmonic systems. We give the general, factorized form of the Hamiltonian for the hierarchy that arises in SUSY theory. The "charge" operators can then be used to convert states among the sectors. We illustrate the approach with two specific anharmonic oscillator models. Using the ground state of the second sector Hamiltonian, we show that the corresponding excited state energies and wave functions of the first sector are accurately obtained by applying the charge operators, using significantly smaller basis sets than are required in a standard variational approach applied to the original Schrodinger equation. This is a consequence of the higher accuracy of the Rayleigh-Ritz variational method when applied for ground states.
At present the basic intellectual aim of academic inquiry is to improve knowledge. Much of the structure, the whole character, of academic inquiry, in universities all over the world, is shaped by the adoption of this as the basic intellectual aim. But, judged from the standpoint of making a contribution to human welfare, academic inquiry of this type is irrational. Three of four of the most elementary rules of rational problem-solving are violated. A revolution in the aims and methods of academic inquiry is needed so that the basic aim becomes to promote wisdom, conceived of as the capacity to realize what is of value, for oneself and others, thus including knowledge and technological know-how, but much else besides. This urgently needed revolution would affect every branch and aspect of the academic enterprise.
Background: Hypertrophic cardiomyopathy (HCM) remains the commonest cause of sudden cardiac death among young athletes. Differentiating between physiologically adaptive left ventricular (LV) hypertrophy observed in athletes' hearts and pathological HCM remains challenging. By quantifying the diffusion of water molecules, diffusion tensor imaging (DTI) MRI allows voxelwise characterization of myocardial microstructure. Purpose: To explore microstructural differences between healthy volunteers, athletes, and HCM patients using DTI. Study Type: Prospective cohort. Population: Twenty healthy volunteers, 20 athletes, and 20 HCM patients. Field Strength/Sequence: 3T/DTI spin echo. Assessment: In-house MatLab software was used to derive mean diffusivity (MD) and fractional anisotropy (FA) as markers of amplitude and anisotropy of the diffusion of water molecules, and secondary eigenvector angles (E2A)-reflecting the orientations of laminar sheetlets. Statistical Tests: Independent samples t-tests were used to detect statistical significance between any two cohorts. Analysis of variance was utilized for detecting the statistical difference between the three cohorts. Statistical tests were twotailed. A result was considered statistically significant at P ≤ 0.05. Results: DTI markers were significantly different between HCM, athletes, and volunteers. HCM patients had significantly higher global MD and E2A, and significantly lower FA than athletes and volunteers. (MD HCM = 1.52 ± 0.06 × 10 −3 mm 2 /s, MD Athletes = 1.49 ± 0.03 × 10 −3 mm 2 /s, MD volunteers = 1.47 ± 0.02 × 10 −3 mm 2 /s, P < 0.05; E2A HCM = 58.8 ± 4 , E2A athletes = 47 ± 5 , E2A volunteers = 38.5 ± 7 , P < 0.05; FA HCM = 0.30 ± 0.02, FA Athletes = 0.35 ± 0.02, FA volunteers = 0.36 ± 0.03, P < 0.05). HCM patients had significantly higher E2A in their thickest segments compared to the remote (E2A thickest = 66.8 ± 7, E2A remote = 51.2 ± 9, P < 0.05). Data Conclusion: DTI depicts an increase in amplitude and isotropy of diffusion in the myocardium of HCM compared to athletes and volunteers as reflected by increased MD and decreased FA values. While significantly higher E2A values in HCM and athletes reflect steeper configurations of the myocardial sheetlets than in volunteers, HCM patients
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