Absorption and Direct Processes in Chaotic Wave Scattering

Recent results on the scattering of waves by chaotic systems with losses and direct processes are discussed. We start by showing the results without direct processes nor absorption. We then discuss systems with direct processes and lossy systems separately. Finally the discussion of systems with both direct processes and loses is given. We will see how the regimes of strong and weak absorption are modified by the presence of the direct processes.Comment: 8 pages, 4 figures, Condensed Matter Physics (IV Mexican Meeting on Mathematical and Experimental Physics), Edited by M. Martinez-Mares and J. A. Moreno-Raz

Anderson Localization in Disordered Vibrating Rods

We study, both experimentally and numerically, the Anderson localization phenomenon in torsional waves of a disordered elastic rod, which consists of a cylinder with randomly spaced notches. We find that the normal-mode wave amplitudes are exponentially localized as occurs in disordered solids. The localization length is measured using these wave amplitudes and it is shown to decrease as a function of frequency. The normal-mode spectrum is also measured as well as computed, so its level statistics can be analyzed. Fitting the nearest-neighbor spacing distribution a level repulsion parameter is defined that also varies with frequency. The localization length can then be expressed as a function of the repulsion parameter. There exists a range in which the localization length is a linear function of the repulsion parameter, which is consistent with Random Matrix Theory. However, at low values of the repulsion parameter the linear dependence does not hold.Comment: 10 pages, 6 figure

Restrictive Immigration Policies and Latino Immigrant Identity in the United States

The United States is presently characterized by rising anti-immigrant sentiment, repressive immigration enforcement, and the negative framing of Latinos as threatening and undesirable. As a result, social boundaries between immigrants and natives have hardened and boundary crossing has become more difficult. Under these circumstances, the prediction of classical assimilation theory is turned on its head: the more time that immigrants spend in the United States and the more contact they have with Americans and American society, the more aware they become of the harsh realities of prejudice and discrimination and the more they come to experience the rampant inequalities of the secondary labor market. Rather than ideologically assimilating, therefore, the greater their experience in the United States, the more likely immigrants are to express a reactive ethnicity that rejects the label “American.” Our work suggests that the greatest threat to the successful assimilation of immigrants comes not from foreign involvements or transnational loyalties, but from the rejection, exclusion, and discrimination that immigrants experience in the United States.Immigration, Exclusion, Discrimination, Latinos, Identity

Restrictive Immigration Policies and Latino Immigrant Identity in the United States

The United States is presently characterized by rising anti-immigrant sentiment, repressive immigration enforcement, and the negative framing of Latinos as threatening and undesirable. As a result, social boundaries between immigrants and natives have hardened and boundary crossing has become more difficult. Under these circumstances, the prediction of classical assimilation theory is turned on its head: the more time that immigrants spend in the United States and the more contact they have with Americans and American society, the more aware they become of the harsh realities of prejudice and discrimination and the more they come to experience the rampant inequalities of the secondary labor market. Rather than ideologically assimilating, therefore, the greater their experience in the United States, the more likely immigrants are to express a reactive ethnicity that rejects the label “American.” Our work suggests that the greatest threat to the successful assimilation of immigrants comes not from foreign involvements or transnational loyalties, but from the rejection, exclusion, and discrimination that immigrants experience in the United States.Immigration, Exclusion, Discrimination, Latinos, Identity