31,451 research outputs found
Golan v. Holder: Copyright in the Image of the First Amendment
Does copyright violate the First Amendment? Professor Melville Nimmer asked this question forty years ago, and then answered it by concluding that copyright itself is affirmatively speech protective. Despite ample reason to doubt Nimmerâs response, the Supreme Court has avoided an independent, thoughtful, plenary review of the question. Copyright has come to enjoy an all-but-categorical immunity to First Amendment constraints. Now, however, the Court faces a new challenge to its back-of-the-hand treatment of this vital conflict. In Golan v. Holder the Tenth Circuit considered legislation (enacted pursuant to the Berne Convention and TRIPS) ârestoringâ copyright protection to millions of foreign works previously thought to belong to the public domain. The Tenth Circuit upheld the legislation, but not without noting that it appeared to raise important First Amendment concerns. The Supreme Court granted certiorari. This article addresses the issues in the Golan case, literally on the eve of oral argument before the Court. This article first considers the Copyright and Treaty Clauses, and then addresses the relationship between copyright and the First Amendment. The discussion endorses an understanding of that relationship in which the Amendment is newly seen as paramount, and copyright is newly seen in the image of the Amendment
Emissivity measurements of reflective surfaces at near-millimeter wavelengths
We have developed an instrument for directly measuring the emissivity of reflective surfaces at near-millimeter wavelengths. The thermal emission of a test sample is compared with that of a reference surface, allowing the emissivity of the sample to be determined without heating. The emissivity of the reference surface is determined by oneâs heating the reference surface and measuring the increase in emission. The instrument has an absolute accuracy of Îe = 5 x 10^-4 and can reproducibly measure a difference in emissivity as small as Îe = 10^-4 between flat reflective samples. We have used the instrument to measure the emissivity of metal films evaporated on glass and carbon fiber-reinforced plastic composite surfaces. We measure an emissivity of (2.15 ± 0.4) x 10^-3 for gold evaporated on glass and (2.65 ± 0.5) x 10^-3 for aluminum evaporated on carbon fiber-reinforced plastic composite
First-principles calculations of the vibrational properties of bulk CdSe and CdSe nanowires
We present first-principles calculations on bulk CdSe and CdSe nanowires with
diameters of up to 22 \AA. Density functional linear combination of atomic
orbitals and plane wave calculations of the electronic and structural
properties are presented and discussed. We use an iterative, symmetry-based
method to relax the structures into the ground state. We find that the band gap
depends on surface termination. Vibrational properties in the whole Brillouin
zone of bulk CdSe and the zone-center vibrations of nanowires are calculated
and analyzed. We find strongly size-dependent and nearly constant modes,
depending on the displacement directions. A comparison with available
experimental Raman data is be given
Entanglement genesis by ancilla-based parity measurement in 2D circuit QED
We present an indirect two-qubit parity meter in planar circuit quantum
electrodynamics, realized by discrete interaction with an ancilla and a
subsequent projective ancilla measurement with a dedicated, dispersively
coupled resonator. Quantum process tomography and successful entanglement by
measurement demonstrate that the meter is intrinsically quantum non-demolition.
Separate interaction and measurement steps allow commencing subsequent data
qubit operations in parallel with ancilla measurement, offering time savings
over continuous schemes.Comment: 5 pages, 4 figures; supplemental material with 5 figure
Composite infrared bolometers with Si_3N_4 micromesh absorbers
We report the design and performance of 300-mK composite bolometers that use micromesh absorbers and support structures patterned from thin films of low-stress silicon nitride. The small geometrical filling factor of the micromesh absorber provides 20Ă reduction in heat capacity and cosmic ray cross section relative to a solid absorber with no loss in IR-absorption efficiency. The support structure is mechanically robust and has a thermal conductance, G < 2 Ă 10^(â11) W/K, which is four times smaller than previously achieved at 300 mK. The temperature rise of the bolometer is measured with a neutron transmutation doped germanium thermistor attached to the absorbing mesh. The dispersion in electrical and thermal parameters of a sample of 12 bolometers optimized for the SunyaevâZelâdovich Infrared Experiment is ±7% in R (T), ±5% in optical efficiency, and ±4% in G
RSFQ devices with selective dissipation for quantum information processing
We study the possibility to use frequency dependent damping in RSFQ circuits
as means to reduce dissipation and consequent decoherence in RSFQ/qubit
circuits. We show that stable RSFQ operation can be achieved by shunting the
Josephson junctions with an circuit instead of a plain resistor. We derive
criteria for the stability of such an arrangement, and discuss the effect on
decoherence and the optimisation issues. We also design a simple flux generator
aimed at manipulating flux qubits
Resolving Non-Determinism in Choreographies
Resolving non-deterministic choices of choreographies is a crucial task. We introduce a novel notion of realisability for choreographies âcalled whole-spectrum implementationâ that rules out deterministic implementations of roles that, no matter which context they are placed in, will never follow one of the branches of a non-deterministic choice. We show that, under some conditions, it is decidable whether an implementation is whole-spectrum. As a case study, we analyse the POP protocol under the lens of whole-spectrum implementation
Satisfying the Einstein-Podolsky-Rosen criterion with massive particles
In 1935, Einstein, Podolsky and Rosen (EPR) questioned the completeness of
quantum mechanics by devising a quantum state of two massive particles with
maximally correlated space and momentum coordinates. The EPR criterion
qualifies such continuous-variable entangled states, where a measurement of one
subsystem seemingly allows for a prediction of the second subsystem beyond the
Heisenberg uncertainty relation. Up to now, continuous-variable EPR
correlations have only been created with photons, while the demonstration of
such strongly correlated states with massive particles is still outstanding.
Here, we report on the creation of an EPR-correlated two-mode squeezed state in
an ultracold atomic ensemble. The state shows an EPR entanglement parameter of
0.18(3), which is 2.4 standard deviations below the threshold 1/4 of the EPR
criterion. We also present a full tomographic reconstruction of the underlying
many-particle quantum state. The state presents a resource for tests of quantum
nonlocality and a wide variety of applications in the field of
continuous-variable quantum information and metrology.Comment: 8 pages, 7 figure
0.75 atoms improve the clock signal of 10,000 atoms
Since the pioneering work of Ramsey, atom interferometers are employed for
precision metrology, in particular to measure time and to realize the second.
In a classical interferometer, an ensemble of atoms is prepared in one of the
two input states, whereas the second one is left empty. In this case, the
vacuum noise restricts the precision of the interferometer to the standard
quantum limit (SQL). Here, we propose and experimentally demonstrate a novel
clock configuration that surpasses the SQL by squeezing the vacuum in the empty
input state. We create a squeezed vacuum state containing an average of 0.75
atoms to improve the clock sensitivity of 10,000 atoms by 2.05 dB. The SQL
poses a significant limitation for today's microwave fountain clocks, which
serve as the main time reference. We evaluate the major technical limitations
and challenges for devising a next generation of fountain clocks based on
atomic squeezed vacuum.Comment: 9 pages, 6 figure
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