Approximately 5 wt% H2O must be driven from a shale to convert it to a high-grade metapelitic rock. Conversely, several wt% H2O must be added to an anhydrous basalt to convert it to a chlorite schist. Clearly, metamorphism in these cases must involve the transport of considerable quantities of H2O. Similarly, CO2 released by decarbonation reactions must also be transported away from the rock.

There are basically two types of nonlinear optical frequency converters. The majority are based on parametric processes, which require phase matching. Devices that use the nonparametric third-order processes of stimulated Raman or Brillouin scattering to shift the optical frequency are the other type. In this chapter, only those based on parametric processes are considered. The first six sections cover practical optical frequency converters that are based on second-order parametric processes, including second-harmonic generation, sum-frequency generation, difference-frequency generation, optical parametric up-conversion, optical parametric down-conversion, optical parametric amplification, optical parametric generation, and optical parametric oscillation. Frequency conversion based on the third-order parametric four-wave mixing of small frequency shifts is discussed in Section 10.7. The generation of high-order harmonics is discussed in Section 10.8.

Although the majority of the U.S. population falls into the middle class, it is often the people at the ends of the distribution who attract the most attention. This chapter discusses the top end of the hierarchy: the upper class. The term millionaire is often used to discuss the wealthy, and indeed, having a million dollars has its advantages. You might be surprised, however, to know that about 12 percent of Americans have $1 million or more in net worth. Those who are truly elite – that is, the smaller proportion of households who own the largest fortunes – have much more than a million dollars in wealth. Indeed, as we saw in Chapter 1, the group at the very top of the wealth distribution – the one percent – has at least $8 million in assets. In this chapter, we build on the basic estimates we provided in Chapter 1 and look more closely at who the top households are. If you are interested in learning about how many Americans fall into various wealth categories, you might explore this online tool: https://dqydj.com/how-many-millionaires-decamillionaires-america/

Education is arguably the most important institution in modern society. While societies have always transmitted knowledge from one generation to another, education today functions as a moderator of stratification and inequality (Buchmann 2001; Shavit and Blossfield 1993). As we can imagine, the lives of the 12 percent of students who drop out of school before earning a high school diploma or certificate (USCB 2018) are vastly different compared to the lives of the 10 percent who earn a graduate or professional degree (NCES 2020a). As we will see, education helps determine what some would consider personal characteristics such as one’s social status (Shavit and Blossfield 1993), occupation (Buchmann and Brakewood 2000; Shavit and Mueller 1997), and family size (Astone and Upchurch 1994). These same factors also predict the educational achievement (Blake 1989; Bourdieu 1977) and attainment (Astone 1991; deGraaf 1988; Pong 1997; Powell and Steelman 1993) of one’s children. Moreover, education correlates with economic well-being, family stability, health, and social connections, that affect not only individuals, but also communities, states, and nations; more educational success equates with national successes (Hout 2012). Education systems can be both formal and informal, however this chapter is primarily interested in formal education systems.

In this chapter we examine how thermodynamic principles can be used to explain why magmas have the compositions they do and what minerals will crystallize from them under any given set of environmental conditions. We do this through the use of phase diagrams, which graphically depict the phase relations. We begin by considering two-component systems, which introduce all of the possible phase relations that can be encountered in the generation of igneous rocks. We then add a third component, which complicates the graphical representations but allows us to deal with compositions that closely approach those of magmas.

Volatile constituents play important roles in the formation and differentiation of magmas. This chapter begins with a discussion of the volatile constituents commonly found in magmas, the most direct evidence for which comes from the gases released during volcanic eruptions. On occasion, these produce violent eruptions that can have global effects on climate.

In previous chapters we have dealt with the specific details of the formation of rocks. In this final chapter, we examine the broader question of their ultimate origin. What conditions in the Earth bring about the formation of rocks? Most rocks are a direct product of changing conditions brought about by tectonic plate motion, which is a direct consequence of convective cooling of the planet.

Almost all igneous and metamorphic rocks consist of aggregates of crystalline minerals. How these crystals form and grow is the subject of this chapter. Thermodynamics tells us which minerals should form under any set of conditions, but the nucleation and growth of these phases is determined by kinetic factors.

To most people, race is essential – meaning it is necessary, basic, and defining. We generally talk about race as something based on physical characteristics, nationality, and religion. However, as we will learn in this chapter, racial categories are often arbitrary in nature and do not precisely describe groups of people, and these categories shift and change across time. Instead, sociologists often refer to ethnicity rather than race when discussing a nexus of behaviors shared by a particular group of people.

On an average day, Jeff Bezos, Amazon’s founder, makes almost $215 million dollars or $21.5 million an hour if we assume he works a ten-hour day. This estimate is based on changes in Bezos’ net worth which is, at least partly, tied to Amazon stocks and fluctuates regularly. But even as a basic estimate, this suggests that Bezos receives considerably more than the average Amazon employee who receives about $15 an hour or $28,466 per year. This amounts to a ratio of 1,433,333:1 in hourly income. Jeff Bezos is currently the richest person in America with a net worth of $137 billion, a sum that allowed him to buy both a $165 million mansion in Beverly Hills and a $90 million plot of land also in Los Angeles (from Microsoft co-founder Paul Allen) in 2020. These purchases were in addition to other properties he already owns in Los Angeles, Seattle, and New York City, which are together worth hundreds of millions of dollars.

In our final chapter, we will answer: who has the power to change society? Clearly, part of the answer is found in the political system. We begin by addressing the power structures associated with a democracy, elections. Who makes the rules that others must follow? As you may recall from previous chapters where the distribution of power was the outcome of interest, this question is perhaps the most pivotal in inequality. While we have seen different theoretical approaches to finding the answer to, “who rules and why?” the fact is, an exceedingly small group of people have immense power over a much larger group.

This chapter deals with three important physical properties of magma: temperature, density, and viscosity. These properties play pivotal roles in the ascent of magma, determining the form of igneous bodies, the style of volcanic eruptions, and the differentiation of magma.