One of the first applications of quantum information to cryptography to be discovered is to the creation of money that cannot be copied. Due to the no-cloning principle, which states that there is no procedure that can copy an arbitrary quantum state, we can hope to create perfectly secure money based on quantum information. In this chapter we study how this can be done by following Wiesner’s idea from the 1970s. To analyze the security of Wiesner’s scheme we develop a formalism for general quantum attacks by studying quantum channels, and encounter some limitations of Wiesner’s scheme.

Chapter 3 reviewed the extraordinary progress in genome sequencing from the completion of the Human Genome Project to the present when it can be said to be crucial in practically every area of biological research. In the context of cancer, huge sequence databases are under construction that have already catalogued several hundred mutations in potential cancer ‘driver’ genes, the ultimate aim being to define mutational signatures for the major cancers. The assignation of ‘potential driver’ distinguishes genes and their protein products that are known or thought to be involved in the regulation of cell proliferation from the majority of ‘passenger’ mutations (see Chapter 2). Before we turn to how mutations in specific genes might cause abnormal proliferation, it behoves us to review how, in normal cells, information from the outside world is transmitted to the cell interior and to the nucleus so that gene expression is appropriately regulated.

This chapter introduces the basic mathematical formalism for working with quantum information. We discover qubits, or quantum bits, how to combine them using the tensor product, and how to measure them by choosing a basis. We discuss unitary operations, which are elementary transformations on qubits. The chapter ends with a convenient representation of qubits as vectors on the 3-dimensional Bloch sphere, and a useful “cheat sheet,” which summarizes useful definitions and identities.

Following our discussion of English vowels in Chapter 3 and rhoticity in Chapter 4, this chapter introduces you to English consonants, as well as variation in consonant inventories across varieties of English. We begin the chapter with a discussion of the characteristics of consonants, focusing on the classification of consonant sounds by place of articulation, manner of articulation, and voicing. This overview also examines consonant inventories cross-linguistically, to help you understand which consonants – and consonant features – are the most common across languages, and why.

The next two sections of the chapter provide an overview of English consonants by introducing the consonant phonemes common to many varieties of English, with variation in these inventories discussed as relevant. A brief overview of modern-day spelling of English consonants is also given. Consonant variation within varieties of English and phonological rules that govern this variation are then discussed. In the final section of the chapter, you will be guided through exercises designed to check your understanding of the content of the chapter and an analysis of your own English consonant inventory.

Delegated computation is a two-party task where there is a large asymmetry between the two parties: on the one hand, Alice would like to execute a quantum computation, but she does not have a powerful enough quantum computer to execute it. On the other hand, Bob has a quantum computer, but he is not trusted by Alice. Can Alice make sure that Bob executes her computation correctly for her? In this chapter we present three very different approaches to this problem. Each of the approaches is based on a different model for quantum computation, and the chapter also serves as an introduction to these models.

A quantum key distribution (QKD) protocol allows two honest users Alice and Bob to harness the advantages of quantum information processing to generate a shared secret key. The most well-known, and indeed the first QKD protocol that was discovered, is called BB’84, after its inventors Bennett and Brassard and the year in which their paper describing the protocol was published. In this chapter we describe the BB’84 protocol and we introduce the main ideas for showing that the protocol is secure.

This chapter will introduce you to the concepts of stress and rhythm in relation to languages and to varieties of English. The chapter begins by defining stress both acoustically and articulatorily, and then examining stress across varieties. This is examined first at the level of the syllable through a focus on strong vs weak syllables in English, and the relationship between strong/weak syllables and stress. The discussion then focuses on the concept of word stress in varieties of English, after which rhythm and pitch accent are introduced, through an examination of stress- and syllable-timing, in different languages as well as varieties of English. This discussion will also present information about the function of stress and pitch accent in various substrate languages for different varieties - such as Cantonese, Malay, Filipino, Spanish, among others - to help you understand the different stress and rhythm patterns that exist across varieties. In the final section of the chapter, you will be guided through exercises designed to check your understanding of the content of the chapter.

This chapter introduces the concept of accent, particularly in relation to dialects and varieties of English.The chapter first defines the word 'accent', and the relationship among accent, dialect, and variety. The chapter then focuses on how we understand and describe accents, and the social meaning that accents convey in different contexts. The chapter then discusses variation within different regional varieties of English, and the use of umbrella terms such as 'British English' or 'American English' to encompass a range of social, regional, and ethnic varieties. The chapter then describes the features of the book; the final section of the chapter has a series of exercises and tasks to guide you through a revision of the contents of the chapter.

In this chapter, we move from discussing English segmentals – individual consonant and vowel sounds – to suprasegmentals, the units of sound above the level of the segment. This includes stress, pitch, and tone, and extends above individual vowel and consonants to syllables, words, phrases, and sentences. At the core of our discussion of suprasegmentals is the syllable, which can be defined as a unit of organization for sound sequences. Every word is made up of minimally one syllable; in some languages, including English, words often contain multiple syllables.

We begin the chapter by examining what we mean by 'syllable', and the components of a syllable, including the onset, nucleus, and coda. We then examine syllable inventories cross-linguistically, with a special focus on the languages that influence varieties of English. An overview of English syllable structure is then provided, with a focus on how syllable structure varies across varieties. In the final section of the chapter, you will be guided through exercises designed to check your understanding of the content of the chapter and to analyse your own English syllable inventory.

Κατέβην χθὲς εἰς Πειραιᾶ µετὰ Γλαύκωνος τοῦ Ἀρίστωνος

In the previous chapters, we examined the vowel inventories across varieties of English, noting that historical changes in English, as well as the influence of different languages, have resulted in substantial differences in how English is spoken around the world.We also mentioned that rhoticity – the production of the ‘r’ sound after a vowel in words such as car and hear – impacts the number of vowels in different varieties of English.Rhoticity is one of the main phonological features distinguishing different varieties; therefore, in this chapter, we will discuss rhoticity in more depth. The chapter first focuses on defining and measuring rhoticity, particularly in terms of formants, which were introduced in Chapter 2. A detailed discussion of both historical and current patterns of rhoticity in varieties of English is then presented. The chapter also discusses /r/-sandhi in varieties of English, and the relationship between /r/-sandhi and rhoticity.

In the final section of the chapter, you will be guided through exercises designed to check your understanding of the content in the chapter. You will also be guided through an analysis of rhoticity in your own English.