1,000 research outputs found
THE ROLE OF REASON IN PLATO’S PHILOSOPHY
The world of the Platonic teaching is a realm of changelessness for a heart saddened by the spectacle of inevitable change. It is order for a mind perturbed by a nightmare of endless chaos. It is the cosmos of reason, of which one may have a glimpse in anything of beauty ... It is the pattern which the mind of man may come to know ... (Edman 1927: xxxviii
Remnant superfluid collective phase oscillations in the normal state of systems with resonant pairing
The signature of superfluidity in bosonic systems is a sound wave-like
spectrum of the single particle excitations which in the case of strong
interactions is roughly temperature independent. In fermionic systems, where
fermion pairing arises as a resonance phenomenon between free fermions and
paired fermionic states (examples are: the atomic gases of lithium or potassium
controlled by a Feshbach resonance, polaronic systems in the intermediary
coupling regime, d-wave hole pairing in the strongly correlated Hubbard
system), remnants of such superfluid characteristics are expected to be visible
in the normal state. The single particle excitations maintain there a sound
wave like structure for wave vectors above a certain q_{min}(T) where they
practically coincide there with the spectrum of the superfluid phase for
T<T_{c}. Upon approaching the transition from above this region in q-space
extends down to small momenta, except for a narrow region around q=0 where such
modes change into damped free particleComment: 5 pages, 3 figures; to appear in Phys Rev
Interplay between pairing and correlations in spin-polarized bound states
We investigate the single and multiple defects embedded in a superconducting
host, studying interplay between the proximity induced pairing and
interactions. We explore influence of the spin-orbit coupling on energies,
polarization and spatial patterns of the bound (Yu-Shiba-Rusinov) states of
magnetic impurities in 2-dimensional square lattice. We also address the
peculiar bound states in the proximitized Rashba chain, resembling the Majorana
quasiparticles, focusing on their magnetic polarization which has been recently
reported by S. Jeon et al., [Science 358, 772 (2017)]. Finally, we study
leakage of these polarized Majorana quasiparticles on the side-attached
nanoscopic regions and confront them with the subgap Kondo effect near to the
singlet-doublet phase transition.Comment: 10 pages, 9 figure
WHY OUGHT WE TO OBEY THE LAW? PLATO'S STARTLING ANSWER
Picture this scenario. Criminal charges have been brought against you. You are tried,
convicted, and sentenced to death. (Mercifully, this could not happen in present-day
South Africa.) While you have been given a procedurally fair trial, the charges
brought against you and your conviction are substantively unjust. You are now in
prison. Two days hence you are to die. What is your state of mind? Calm? Agitated?
Depressed? Now suppose a friend arrives to visit you. He tells you that plans have
been made for your escape, that your warder can easily be bribed, and that a car is
waiting outside to whisk you away to a safe and secret destination. How do you react?
Rejoice and run? Stay put and face the prospect of death? Most people in such a
situation, we may agree, would escape without hesitation
Rating of Mixed Split Residential Air Conditioners
A methodology is presented for rating the performance
of mixed, split residential air conditioners.
The method accounts for the impact on system
performance of the indoor evaporator, expansion
device and fan; three major components that are
likely to be substituted for the matched components
in a mixed system. The method allows calculation of
capacity at 95°F rating point and seasonal energy
efficiency ratio, SEER, without performing laboratory
test of the complete system. Limitations of
the procedure, present work, and anticipated
improvements are also discussed
Simple theory of extremely overdoped HTS
We demonstrate the existence of a simple physical picture of
superconductivity for extremely overdoped CuO2 planes. It possesses all
characteristic features of HTS, such as a high superconducting transition
temperature, the symmetry of order parameter, and the
coexistence of a single electron Fermi surface and a pseudogap in the normal
state. Values of pseudogap are calculated for different doping levels. An
orbital paramagnetism of preformed pairs is predicted.Comment: 7 pages, 1 figur
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