Search results for "ustice"
showing 10 items of 1381 documents
Political Responsibility Refocused: Thinking Justice after Iris Marion Young
2015
One of the most significant challenges that twenty-first-century philosophy has to face is to think about our moral and political responsibility in collective and global contexts. In our globalized...
La argumentación y el humor desde la ética del discurso
2019
En este trabajo me concentro en el hecho de la argumentación en Karl-Otto Apel, para intentar comprender, según este autor, en qué consiste, por qué es tan importante para la fundamentación de la ética y qué significa argumentar racionalmente. A partir de ahí camino con Apel más allá de Apel mostrando la importancia de incorporar la dimensión del humor para que la argumentación realmente avance hacia la verdad y la justicia. In this paper I concentrate on the fact of arguing in Karl-Otto Apel, to try to understand, according to this author, what it is, why it is so important for the foundation of ethics and what it means to argue rationally. From there I walk with Apel beyond Apel showing t…
Justice in Finnish Food Policies
2023
Abstract The need to create more sustainable food systems calls for careful attention to justice in making the transition. However, to achieve a just transition and create policies to support the goal of developing sustainable food systems, we need more knowledge of the ways current policies tackle justice. This knowledge can reveal blind spots and development needs and increase the transparency of potentially conflicting goals, which is essential for designing just transition policies. From the normative perspective of food justice, a food system should produce three principal outcomes: food security and nutrition, livelihoods and fair income, and environmental sustainability. In this arti…
Size-And Wavelength-Dependent Two-Photon Absorption Cross-Section of CsPbBr3 Perovskite Quantum Dots
2017
All-inorganic colloidal perovskite quantum dots (QDs) based on cesium, lead, and halide have recently emerged as promising light emitting materials. CsPbBr3 QDs have also been demonstrated as stable two-photon-pumped lasing medium. However, the reported two photon absorption (TPA) cross sections for these QDs differ by an order of magnitude. Here we present an in-depth study of the TPA properties of CsPbBr3 QDs with mean size ranging from 4.6 to 11.4 nm. By using femtosecond transient absorption (TA) spectroscopy we found that TPA cross section is proportional to the linear one photon absorption. The TPA cross section follows a power law dependence on QDs size with exponent 3.3 +- 0.2. The …
Foundations of quantum mechanics and their impact on contemporary society
2018
Nearing a century since its inception, quantum mechanics is as lively as ever. Its signature manifestations, such as superposition, wave-particle duality, uncertainty principle, entanglement and nonlocality, were long confronted as weird predictions of an incomplete theory, paradoxes only suitable for philosophical discussions, or mere mathematical artifacts with no counterpart in the physical reality. Nevertheless, decades of progress in the experimental verification and control of quantum systems have routinely proven detractors wrong. While fundamental questions still remain wide open on the foundations and interpretations of quantum mechanics, its modern technological applications have …
Scattering Amplitudes from Superconformal Ward Identities
2018
We consider finite superamplitudes of N=1 matter, and use superconformal symmetry to derive powerful first-order differential equations for them. Because of on-shell collinear singularities, the Ward identities have an anomaly, which is obtained from lower-loop information. We show that in the five-particle case, the solution to the equations is uniquely fixed by the expected analytic behavior. We apply the method to a nonplanar two-loop five-particle integral. We consider finite superamplitudes of N=1 matter, and use superconformal symmetry to derive powerful first-order differential equations for them. Due to on-shell collinear singularities, the Ward identities have an anomaly, which is …
Structure formation during an early period of matter domination
2014
In this work we show that modifying the thermal history of the Universe by including an early period of matter domination can lead to the formation of astronomical objects. However, the survival of these objects can only be possible if the dominating matter decays to a daughter particle which is not only almost degenerate with the parent particle but also has an open annihilation channel. This requirement translates in an upper bound for the coupling of such a channel and makes the early structure formation viable.
Spin-layer locking of interlayer excitons trapped in moir\'e potentials
2019
Van der Waals heterostructures offer attractive opportunities to design quantum materials. For instance, transition metal dichalcogenides (TMDs) possess three quantum degrees of freedom: spin, valley index, and layer index. Further, twisted TMD heterobilayers can form moir\'e patterns that modulate the electronic band structure according to atomic registry, leading to spatial confinement of interlayer exciton (IXs). Here we report the observation of spin-layer locking of IXs trapped in moir\'e potentials formed in a heterostructure of bilayer 2H-MoSe$_2$ and monolayer WSe$_2$. The phenomenon of locked electron spin and layer index leads to two quantum-confined IX species with distinct spin-…
Momentum structure of the self-energy and its parametrization for the two-dimensional Hubbard model
2016
We compute the self-energy for the half-filled Hubbard model on a square lattice using lattice quantum Monte Carlo simulations and the dynamical vertex approximation. The self-energy is strongly momentum dependent, but it can be parametrized via the non-interacting energy-momentum dispersion $\varepsilon_{\mathbf{k}}$, except for pseudogap features right at the Fermi edge. That is, it can be written as $\Sigma(\varepsilon_{\mathbf{k}},\omega)$, with two energy-like parameters ($\varepsilon$, $\omega$) instead of three ($k_x$, $k_y$ and $\omega$). The self-energy has two rather broad and weakly dispersing high energy features and a sharp $\omega= \varepsilon_{\mathbf{k}}$ feature at high tem…
The Vlasov Limit for a System of Particles which Interact with a Wave Field
2008
In two recent publications [Commun. PDE, vol.22, p.307--335 (1997), Commun. Math. Phys., vol.203, p.1--19 (1999)], A. Komech, M. Kunze and H. Spohn studied the joint dynamics of a classical point particle and a wave type generalization of the Newtonian gravity potential, coupled in a regularized way. In the present paper the many-body dynamics of this model is studied. The Vlasov continuum limit is obtained in form equivalent to a weak law of large numbers. We also establish a central limit theorem for the fluctuations around this limit.