On the embeddability of certain infinitely divisible probability measures on Lie groups

We describe certain sufficient conditions for an infinitely divisible probability measure on a class of connected Lie groups to be embeddable in a continuous one-parameter convolution semigroup of probability measures. (Theorem 1.3). This enables us in particular to conclude the embeddability of all infinitely divisible probability measures on certain Lie groups, including the so called Walnut group (Corollary 1.5). The embeddability is concluded also under certain other conditions (Corollary 1.4 and Theorem 1.6).Comment: 24 page

Symmetry and optical selection rules in graphene quantum dots

Graphene quantum dots (GQD's) have optical properties which are very different from those of an extended graphene sheet. In this Article we explore how the size, shape and edge--structure of a GQD affect its optical conductivity. Using representation theory, we derive optical selection rules for regular-shaped dots, starting from the symmetry properties of the current operator. We find that, where the x- and y-components of the current operator transform with the same irreducible representation (irrep) of the point group - for example in triangular or hexagonal GQD's - the optical conductivity is independent of the polarisation of the light. On the other hand, where these components transform with different irreps - for example in rectangular GQD's - the optical conductivity depends on the polarisation of light. We find that GQD's with non-commuting point-group operations - for example dots of rectangular shape - can be distinguished from GQD's with commuting point-group operations - for example dots of triangular or hexagonal shape - by using polarized light. We carry out explicit calculations of the optical conductivity of GQD's described by a simple tight--binding model and, for dots of intermediate size, \textcolor{blue}{($10 \lesssim L \lesssim 50\ \text{nm}$)} find an absorption peak in the low--frequency range of the spectrum which allows us to distinguish between dots with zigzag and armchair edges. We also clarify the one-dimensional nature of states at the van Hove singularity in graphene, providing a possible explanation for very high exciton-binding energies. Finally we discuss the role of atomic vacancies and shape asymmetry.Comment: 24 pages, 15 figure

Ethnographic Moment: Navajo Nation Changing Racial Terminology in Response to Black Lives Matter Protests

Given Navajo Nation debates about changing racial terminology in response to Black Lives Matter protests, I will argue that modification of Diné Bizaad (Diné Bizaad means Navajo Language) is a progressive and positive shift. Language is constantly changing across social groups and time. From generation to generation, words take on different meanings. Words are invented and acquired from a variety of sources. Furthermore, unused words can expire from everyday usage. How do shifts in language occur

A Grief Intervention for Early Perinatal Loss

Early pregnancy loss has a multidimensional effect on patients, touching the body, soul, and spirit. This project addresses patients’ lack of spiritual and emotional support following early pregnancy loss, commonly called a miscarriage. The available research on the emotional impact of early pregnancy loss has grown stronger over the last three decades. However, there is a deficit of research exploring the spiritual implications of miscarriage and how faith is used as a coping mechanism for pregnancy grief. In modern culture, the term spirituality can mean many different things. With this awareness, Mercy Healthcare embraces and supports patients wherever they find themselves spiritually. As a faith-based institution, Mercy acknowledges the importance of spirituality and personal faith in the healing process. When supporting early pregnancy loss at Mercy Springfield, the Pastoral Services department has a definitive standard of care. Nevertheless, a lack of vital ongoing support is unavailable for patients who desire additional assistance in their grief. This study creates an intervention to support the grief of early pregnancy loss patients through an eight-week phenomenological review considering individual life and faith stories. This project, led by a professionally trained chaplain, applied both qualifiable and quantifiable research techniques using patient and stakeholder surveys and the project leader’s observational data. It investigates whether further understanding one’s life stories and faith experiences can promote quality patient care in their grieving process. The project will also provide additional resources to promote awareness and support of the spiritual aspects of miscarriage grief. In addition, this study will serve as a guide to further evaluate quality patient care offered by Pastoral Services at Mercy Springfield

Cancer

This poster for the Natural Sciences Poster Session at Parkland College features the constellation Cancer, its ten brightest stars and Messier objects. Cancer (the crab) is a zodiac constellations located between Leo and Gemini. The student identified the ten different key stars and graphed their altitudes and azimuth to calculate their lifespans. He also described the two Messier objects and calculated how many days are in a year according to the rise times of a star in the constellation

Cancer

This poster for the Natural Sciences Poster Session at Parkland College features the constellation Cancer, its ten brightest stars and Messier objects. Cancer (the crab) is a zodiac constellations located between Leo and Gemini. The student identified the ten different key stars and graphed their altitudes and azimuth to calculate their lifespans. He also described the two Messier objects and calculated how many days are in a year according to the rise times of a star in the constellation

Strong Electronic Correlation Effects in Coherent Multidimensional Nonlinear Optical Spectroscopy

We discuss a many−body theory of the coherent ultrafast nonlinear optical response of systems with a strongly correlated electronic ground state that responds unadiabatically to photoexcitation. We introduce a truncation of quantum kinetic density matrix equations of motion that does not rely on an expansion in terms of the interactions and thus applies to strongly correlated systems. For this we expand in terms of the optical field, separate out contributions to the time−evolved many−body state due to correlated and uncorrelated multiple optical transitions, and use “Hubbard operator” density matrices to describe the exact dynamics of the individual contributions within a subspace of strongly coupled states, including “pure dephasing”. Our purpose is to develop a quantum mechanical tool capable of exploring how, by coherently photoexciting selected modes, one can trigger nonlinear dynamics of strongly coupled degrees of freedom. Such dynamics could lead to photoinduced phase transitions. We apply our theory to the nonlinear response of a two−dimensional electron gas (2DEG) in a magnetic field. We coherently photoexcite the two lowest Landau level (LL) excitations using three time−delayed optical pulses. We identify some striking temporal and spectral features due to dynamical coupling of the two LLs facilitated by inter−Landau−level magnetoplasmon and magnetoroton excitations and compare to three−pulse four−wave−mixing (FWM) experiments. We show that these features depend sensitively on the dynamics of four−particle correlations between an electron−hole pair and a magnetoplasmon/magnetoroton, reminiscent of exciton−exciton correlations in undoped semiconductors. Our results shed light into unexplored coherent dynamics and relaxation of the quantum Hall system (QHS) and can provide new insight into non−equilibrium co−operative phenomena in strongly correlated systems

When evaluating a president’s economic performance, voters look across their entire record – not just the recent short term.

How do voters decide? Do they take everything into account that happened over the government’s time in office? Or do they rely only on the recent past? Timothy Hellwig and Dani M. Marinova report that voters, counter to conventional understandings, are not so short-sighted. Their analysis of vote intentions in the run up to the 2012 presidential election reveals that voters are no more accurate in assessing economic performance over the short term compared to the long term. Voters, it turns out, are more misinformed than short-sighted

Ultrafast Enhancement of Ferromagnetism via Photoexcited Holes in GaMnAs

We report on the observation of ultrafast photo-enhanced ferromagnetism in GaMnAs. It is manifested as a transient magnetization increase on a 100-ps time scale, after an initial sub-ps demagnetization. The dynamic magnetization enhancement exhibits a maximum below the Curie temperature Tc and dominates the demagnetization component when approaching Tc. We attribute the observed ultrafast collective ordering to the p-d exchange interaction between photoexcited holes and Mn spins, leading to a correlation-induced peak around 20K and a transient increase in Tc.Comment: 4 page

Pemetaan Kerawanan Banjir dengan Aplikasi Sistem Informasi Geografis di Sub DAS Karang Mumus Provinsi Kalimantan Timur

Sub DAS Karang Mumus merupakan bagian dari sistem DAS Mahakam yang lebih besar, memiliki luas ±30.000 ha dianggap memiliki kontribusi dalam menentukan kerawanan banjir yang sering terjadi di Kota Samarinda dan sekitarnya. Tujuan penelitian ini adalah memetakan daerah yang termasuk dalam daerah rawan kebanjiran dan daerah yang berpotensi sebagai pemasok air banjir menggunakan metode teknik mitigasi bencana dan Sistem Informasi Geografis (SIG). Teknik mitigasi bencana membagi dua kajian utama, yakni kajian daerah rawan kebanjiran menggunakan parameter bentuk lahan, lahan kiri-kanan sungai, percabangan sungai, sinusitas sungai, bangunan air. Kajian daerah potensi pemasok air banjir menggunakan parameter hidrologi sungai yakni curah hujan, bentuk DAS, gradien sungai, kerapatan drainase, kemiringan lereng, penggunaan lahan. Analisis dilakukan dengan menggunakan metode skoring dan pembobotan. Sistem Informasi Geografis digunakan sebagai permodelan spasial dalam memetakan kerawanan dan potensi banjir menggunakan teknik overlay/intersect dan merepresentasikannya dalam bentuk peta