226 research outputs found
One thousand good things in Nature: aspects of nearby Nature associated with improved connection to Nature
As our interactions with nature occur increasingly within urban landscapes, there is a need to consider how âmundane natureâ can be valued as a route for people to connect to nature. The content of a three good things in nature intervention, written by 65 participants each day for five days is analysed. Content analysis produced themes related to sensations, temporal change, active wildlife, beauty, weather, colour, good feelings and specific aspects of nature. The themes describe the everyday good things in nature, providing direction for those seeking to frame engaging conservation messages, plan urban spaces and connect people with nearby nature
Resourceâbased learning strategies: Implications for students and institutions
This paper reports some findings from a project in implementing resourceâbased learning in economics, and identifies some implications for students and institutions. These include student responses to a midâsemester evaluation and the views of the project team. The latter have been informed by action research which sought to recognize studentsâ individual differences, employ active learning methods and, above all, integrate IT into the curriculum. While innovative strategies are clearly welcomed, students show strong attachment to some traditional methods. Most of those who suggested changes to the range of activities asked for reinstatement of at least some lectures, generally as additions to existing activities. Implications include the need for students and staff to acquire a wide range of new skills, for largeâscale curriculum review if new learning technologies are to be fully integrated, and the need to acknowledge that, given student and staff perceptions of change, the process may be long and costly
Integrability breaking and bound states in Google's decorated XXZ circuits
Recent quantum simulation by Google [Nature 612, 240 (2022)] has demonstrated
the formation of bound states of interacting photons in a quantum-circuit
version of the XXZ spin chain. While such bound states are protected by
integrability in a one-dimensional chain, the experiment found the bound states
to be unexpectedly robust when integrability was broken by decorating the
circuit with additional qubits, at least for small numbers of qubits () within the experimental capability. Here we scrutinize this result by
state-of-the-art classical simulations, which greatly exceed the experimental
system sizes and provide a benchmark for future studies in larger circuits. We
find that the bound states consisting of a small and finite number of photons
are indeed robust in the non-integrable regime, even after scaling to the
infinite time and infinite system size limit. Moreover, we show that such
systems possess unusual spectral properties, with level statistics that
deviates from the random matrix theory expectation. On the other hand, for low
but finite density of photons, we find a much faster onset of thermalization
and significantly weaker signatures of bound states, suggesting that anomalous
dynamics may only be a property of dilute systems with zero density of photons
in the thermodynamic limit. The robustness of the bound states is also
influenced by the number of decoration qubits and, to a lesser degree, by the
regularity of their spatial arrangement.Comment: 19 pages, 15 figure
The invisible plan: how English teachers develop their expertise and the special place of adapting the skills of lesson planning
This paper analyses how English teachers learn to become expert designers of learning and why sharing that expertise is increasingly vital. Its conceptual framework is the widely recognised, empirically tested, five-stage developmental Dreyfus model of skill acquisition, exemplifying the development of teacher expertise, constituted by the âmilestoneâ [m] and âtransitoryâ [t] phases connecting with the five stages of: Novice [m], Advanced Beginner [t], Competent [m], Proficient [t] and Expert [m]. Teacher planning is analysed as one key tacit or non-tangible component of developing expertise. Focusing specifically on English teachers as key participants in this pioneer teacher cognition study, the defining characteristics of milestone stages of expertise development are explored with specific attention to the remarkably under-researched area of planning. We introduce three new categories, defining modes of planning: (i) visible practical planning, (ii) external reflective planning and (iii) internal reflective planning, demonstrating their role in teacher development through the Dreyfus five stages. English is a subject which suffers from frequent disruptive changes to curriculum and assessment: new learning designs are constantly demanded, making planning an ongoing challenge. The implications for practice include the importance of an explicit understanding of how teachersâ planning moves through the three phases from the very âvisibleâ novice phase to the internal relatively âautomaticâ competent teacher and finally the seemingly âinvisibleâ expert phase. Further research is needed to explore how English teachers can share planning expertise between the three phases to improve teachersâ skills and student learning
All-sky LIGO Search for Periodic Gravitational Waves in the Early S5 Data
We report on an all-sky search with the LIGO detectors for periodic
gravitational waves in the frequency range 50--1100 Hz and with the frequency's
time derivative in the range -5.0E-9 Hz/s to zero. Data from the first eight
months of the fifth LIGO science run (S5) have been used in this search, which
is based on a semi-coherent method (PowerFlux) of summing strain power.
Observing no evidence of periodic gravitational radiation, we report 95%
confidence-level upper limits on radiation emitted by any unknown isolated
rotating neutron stars within the search range. Strain limits below 1.E-24 are
obtained over a 200-Hz band, and the sensitivity improvement over previous
searches increases the spatial volume sampled by an average factor of about 100
over the entire search band. For a neutron star with nominal equatorial
ellipticity of 1.0E-6, the search is sensitive to distances as great as 500
pc--a range that could encompass many undiscovered neutron stars, albeit only a
tiny fraction of which would likely be rotating fast enough to be accessible to
LIGO. This ellipticity is at the upper range thought to be sustainable by
conventional neutron stars and well below the maximum sustainable by a strange
quark star.Comment: 6 pages, 1 figur
Search for Gravitational Wave Bursts from Soft Gamma Repeaters
We present the results of a LIGO search for short-duration gravitational
waves (GWs) associated with Soft Gamma Repeater (SGR) bursts. This is the first
search sensitive to neutron star f-modes, usually considered the most efficient
GW emitting modes. We find no evidence of GWs associated with any SGR burst in
a sample consisting of the 27 Dec. 2004 giant flare from SGR 1806-20 and 190
lesser events from SGR 1806-20 and SGR 1900+14 which occurred during the first
year of LIGO's fifth science run. GW strain upper limits and model-dependent GW
emission energy upper limits are estimated for individual bursts using a
variety of simulated waveforms. The unprecedented sensitivity of the detectors
allows us to set the most stringent limits on transient GW amplitudes published
to date. We find upper limit estimates on the model-dependent isotropic GW
emission energies (at a nominal distance of 10 kpc) between 3x10^45 and 9x10^52
erg depending on waveform type, detector antenna factors and noise
characteristics at the time of the burst. These upper limits are within the
theoretically predicted range of some SGR models.Comment: 6 pages, 1 Postscript figur
Quantum state preparation and macroscopic entanglement in gravitational-wave detectors
Long-baseline laser-interferometer gravitational-wave detectors are operating
at a factor of 10 (in amplitude) above the standard quantum limit (SQL) within
a broad frequency band. Such a low classical noise budget has already allowed
the creation of a controlled 2.7 kg macroscopic oscillator with an effective
eigenfrequency of 150 Hz and an occupation number of 200. This result, along
with the prospect for further improvements, heralds the new possibility of
experimentally probing macroscopic quantum mechanics (MQM) - quantum mechanical
behavior of objects in the realm of everyday experience - using
gravitational-wave detectors. In this paper, we provide the mathematical
foundation for the first step of a MQM experiment: the preparation of a
macroscopic test mass into a nearly minimum-Heisenberg-limited Gaussian quantum
state, which is possible if the interferometer's classical noise beats the SQL
in a broad frequency band. Our formalism, based on Wiener filtering, allows a
straightforward conversion from the classical noise budget of a laser
interferometer, in terms of noise spectra, into the strategy for quantum state
preparation, and the quality of the prepared state. Using this formalism, we
consider how Gaussian entanglement can be built among two macroscopic test
masses, and the performance of the planned Advanced LIGO interferometers in
quantum-state preparation
First LIGO search for gravitational wave bursts from cosmic (super)strings
We report on a matched-filter search for gravitational wave bursts from
cosmic string cusps using LIGO data from the fourth science run (S4) which took
place in February and March 2005. No gravitational waves were detected in 14.9
days of data from times when all three LIGO detectors were operating. We
interpret the result in terms of a frequentist upper limit on the rate of
gravitational wave bursts and use the limits on the rate to constrain the
parameter space (string tension, reconnection probability, and loop sizes) of
cosmic string models.Comment: 11 pages, 3 figures. Replaced with version submitted to PR
Astrophysically Triggered Searches for Gravitational Waves: Status and Prospects
In gravitational-wave detection, special emphasis is put onto searches that
focus on cosmic events detected by other types of astrophysical observatories.
The astrophysical triggers, e.g. from gamma-ray and X-ray satellites, optical
telescopes and neutrino observatories, provide a trigger time for analyzing
gravitational wave data coincident with the event. In certain cases the
expected frequency range, source energetics, directional and progenitor
information is also available. Beyond allowing the recognition of gravitational
waveforms with amplitudes closer to the noise floor of the detector, these
triggered searches should also lead to rich science results even before the
onset of Advanced LIGO. In this paper we provide a broad review of LIGO's
astrophysically triggered searches and the sources they target
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