4,618 research outputs found
Delayed-choice gedanken experiments and their realizations
The wave-particle duality dates back to Einstein's explanation of the
photoelectric effect through quanta of light and de Broglie's hypothesis of
matter waves. Quantum mechanics uses an abstract description for the behavior
of physical systems such as photons, electrons, or atoms. Whether quantum
predictions for single systems in an interferometric experiment allow an
intuitive understanding in terms of the particle or wave picture, depends on
the specific configuration which is being used. In principle, this leaves open
the possibility that quantum systems always either behave definitely as a
particle or definitely as a wave in every experimental run by a priori adapting
to the specific experimental situation. This is precisely what is tried to be
excluded by delayed-choice experiments, in which the observer chooses to reveal
the particle or wave character -- or even a continuous transformation between
the two -- of a quantum system at a late stage of the experiment. We review the
history of delayed-choice gedanken experiments, which can be traced back to the
early days of quantum mechanics. Then we discuss their experimental
realizations, in particular Wheeler's delayed choice in interferometric setups
as well as delayed-choice quantum erasure and entanglement swapping. The latter
is particularly interesting, because it elevates the wave-particle duality of a
single quantum system to an entanglement-separability duality of multiple
systems
Sustainability in the Fashion Industry
This paper examines companies\u27 ratings related to sustainability, particularly for fast fashion brands. The low costs of fast fashion have become an attractive purchase option for consumers, however, in more recent years, social, environmental, and economic concerns have placed sustainability at the center of research studies. It is expected that fast fashion products will continue to influence consumers to purchase from brands that are less sustainable than other brands that may incur higher prices. Factors taken into consideration include three different Fashion Transparency Indexes, Good on You rating, the Company’s yearly sales, and the age of the company. The results will shed light on whether consumers are conscious of, and take into consideration, the ethical, social, economic, or environmental issues when purchasing clothing
Visual Question Answering with Memory-Augmented Networks
In this paper, we exploit a memory-augmented neural network to predict
accurate answers to visual questions, even when those answers occur rarely in
the training set. The memory network incorporates both internal and external
memory blocks and selectively pays attention to each training exemplar. We show
that memory-augmented neural networks are able to maintain a relatively
long-term memory of scarce training exemplars, which is important for visual
question answering due to the heavy-tailed distribution of answers in a general
VQA setting. Experimental results on two large-scale benchmark datasets show
the favorable performance of the proposed algorithm with a comparison to state
of the art.Comment: CVPR 201
Natural Language Processing with Small Feed-Forward Networks
We show that small and shallow feed-forward neural networks can achieve near
state-of-the-art results on a range of unstructured and structured language
processing tasks while being considerably cheaper in memory and computational
requirements than deep recurrent models. Motivated by resource-constrained
environments like mobile phones, we showcase simple techniques for obtaining
such small neural network models, and investigate different tradeoffs when
deciding how to allocate a small memory budget.Comment: EMNLP 2017 short pape
Experimental quantum teleportation over a high-loss free-space channel
We present a high-fidelity quantum teleportation experiment over a high-loss
free-space channel between two laboratories. We teleported six states of three
mutually unbiased bases and obtained an average state fidelity of 0.82(1), well
beyond the classical limit of 2/3. With the obtained data, we tomographically
reconstructed the process matrices of quantum teleportation. The free-space
channel attenuation of 31 dB corresponds to the estimated attenuation regime
for a down-link from a low-earth-orbit satellite to a ground station. We also
discussed various important technical issues for future experiments, including
the dark counts of single-photon detectors, coincidence-window width etc. Our
experiment tested the limit of performing quantum teleportation with
state-of-the-art resources. It is an important step towards future
satellite-based quantum teleportation and paves the way for establishing a
worldwide quantum communication network
Good news or bad news, which do you want first? The importance of the sequence and organization of Information for financial decision-making: a neuro-electrical imaging study
Investment decisions are largely based on the information investors received from the target firm. Thaler introduced the hedonic editing framework, in which suggests that integration/segregation of information influence individual's perceived value. Meanwhile, when evaluating the evidence and information in a sequence, order effect and biases have been found to have an impact in various areas. In this research, the influence of the Organization of Information (Integration vs. Segregation) and the Sequence of Information (Negative-Positive order vs. Positive-Negative order) on individual's investment decision-making both at the behavioral level (decision) and neurometrix level (measured by an individual's emotion and Approach Withdraw tendency) was assessed for the three groups of information: a piece of Big Positive Information and a piece of Small Negative Information, a piece of Big Negative Information and a piece of Small Positive Information, and a piece of Small Negative information. The behavioral results, which are an individual's final investment decision, were consistent for all three scenarios. In general, individuals will invest more/retire less when receiving two pieces of information in a Negative-Positive order. However, the neurometric results (Emotional Index, Approach Withdraw Index and results from LORETA) show differences among information groups. An effect of the Sequence of Information and the Organization of Information was found for the different scenarios. The results suggest that in the scenarios that involve large-scale information, the organization of information (Integration vs. Segregation) influences the emotion and Approach Withdraw tendency. The results of this investigation should provide insight for effective communication of information, especially when large-scale information is involved
Salir de la zona de confort. Dilemas y Desafíos en el EEES
Este artículo trata sobre las resistencias del estudiantado y el profesorado ante los desafíos que supone trabajar con metodologías coherentes con el EEES, centrándonos en el tránsito entre la zona de confort y la zona de aprendizaje. Para dar cuenta ello se analizan y relatan los desafíos, dilemas y avances respecto a este reto, en el marco del trabajo realizado en el grupo de innovación docente Indaga-t, destacando como se ha ido configurando un nuevo rol de docente y estudiante
A high-speed tunable beam splitter for feed-forward photonic quantum information processing
We realize quantum gates for path qubits with a high-speed,
polarization-independent and tunable beam splitter. Two electro-optical
modulators act in a Mach-Zehnder interferometer as high-speed phase shifters
and rapidly tune its splitting ratio. We test its performance with heralded
single photons, observing a polarization-independent interference contrast
above 95%. The switching time is about 5.6 ns, and a maximal repetition rate is
2.5 MHz. We demonstrate tunable feed-forward operations of a single-qubit gate
of path-encoded qubits and a two-qubit gate via measurement-induced interaction
between two photons
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