Exact bidirectional X-wave solutions in fiber Bragg gratings

We find exact solutions describing bidirectional pulses propagating in fiber Bragg gratings. They are derived by solving the coupled-mode theory equations and are expressed in terms of products of modified Bessel functions with algebraic functions. Depending on the values of the two free parameters the general bidirectional X-wave solution can also take the form of a unidirectional pulse. We analyze the symmetries and the asymptotic properties of the solutions and also discuss about additional waveforms that are obtained by interference of more than one solutions. Depending on their parameters such pulses can create a sharp focus with high contrast

The Regime Complex for Managing Global Cyber Activities

When we try to understand cyber governance, it is important to remember how new cyberspace is. “Cyberspace is an operational domain framed by use of electronics to…exploit information via interconnected systems and their associated infra structure” (Kuehl 2009). While the US Defense Department sponsored a modest connection of a few computers called ARPANET (Advanced Research Projects Agency Network) in 1969, and the World Wide Web was conceived in 1989, it has only been in the last decade and a half that the number of websites burgeoned, and businesses begin to use this new technology to shift production and procurement in complex global supply chains. In 1992, there were only a million users on the Internet (Starr 2009, 52); today, there are nearly three billion, and the Internet has become a substrate of modern economic, social and political life. And the volatility continues. Analysts are now trying to understand the implications of ubiquitous mobility, the “Internet of everything” and storage of “big data.” Over the past 15 years, the advances in technology have far outstripped the ability of institutions of governance to respond, as well as our thinking about governance. Since the 1970s, political scientists have looked at the international governance processes of various global affairs issues through the perspective of regime theory (Keohane and Nye 1977; Ruggie 1982). This paper is a mapping exercise of cyber governance using regime theory. Regimes are the “principles, norms, rules and procedures that govern issue areas in international affairs,” but these concepts have rarely been applied to the new cyber domain (Krasner 1983). In its early days, thinking about cyber governance was relatively primitive. Ideological libertarians proclaimed that “information wants to be free,” portraying the Internet as the end of government controls. In practice, however, governments and geographical jurisdictions have been playing a major role in cyber governance right from the start

Leadership and American Foreign Policy

Conference by Joseph S. Nye, Jr. at the bilateral seminar on 'Foreign Policy Priorities for the Next US President', held in Madrid on 19 May 2008 and organised by the Center for Strategic & International Studies (CSIS) and the Elcano Royal Institute, with the cooperation of the Spanish Ministry of Foreign Affairs and Cooperation

The Information Revolution and Soft Power

The rise of digital networks is diffusing power to new players. Fourth in a series on soft power

Book review: “is the American century over?”

In his latest book, Is the American Century Over?, Professor Joseph S. Nye argues that, despite the rise of China, America is not declining. Instead, he writes, we are seeing the rise of the rest. The book is reviewed by Jonathan Freeman

Nuclear Lessons for Cyber Security?

Identifying “revolutions in military affairs” is arbitrary, but some inflection points in technological change are larger than others: for example, the gunpowder revolution in early modern Europe, the industrial revolution of the nineteenth century, the second industrial revolution of the early twentieth century, and the nuclear revolution in the middle of the last century. In this century, we can add the information revolution that has produced today’s extremely rapid growth of cyberspace. Earlier revolutions in information technology, such as Gutenberg’s printing press, also had profound political effects, but the current revolution can be traced to Moore’s law and the thousand-fold decrease in the costs of computing power that occurred in the last quarter of the twentieth century. Political leaders and analysts are only beginning to come to terms with this transformative technology

Transformational Leadership And American Foreign Policy: A Preliminary Analysis

Foreign policy is usually over-determined. The “national interest” often appears to be an immutable dictation of the international system and of domestic politics. As Henry Kissinger put it when he was Secretary of State, “the essential outlines of U.S. policy will remain the same no matter who wins the U.S. Presidential election” (Wittkopf, 2003, 524). Yet sometimes, “reality” is more malleable than it first appears. Not so long ago, it seemed “unimaginable” that the Soviet Union would disappear and Germany would be peacefully reunited. As former National Security Advisor Brent Scowcroft put it in 2003, the main divisions in foreign policy today are not between liberals and conservatives, but between the traditionalists and the transformationalists.1 The transformationalists believe that “we know what has to be done and have the power to do it. What has to be done is to transform the Middle East into a collection of democracies. That will bring peace and stability” (Rothkopf, 2005, 428). Transformational leadership has become a central part of the current debate about American foreign policy

Preface and Chapter Five “Soft power and American foreign policy”, in Soft Power, Public Affairs, New Hampshire, 2004, ps. IX-XIII y 127-147

El presente fragmento de la famosa obra del profesor Nye, nos introduce en el concepto y repercusiones del poder blando. Definido como “la habilidad de obtener lo que quieres a través de la atracción antes que a través de la coerción o de las recompensas”, este concepto tiene una gran relevancia para la política exterior de Estados Unidos. Tras exponer las diferentes corrientes de la política exterior americana y las consecuencias negativas que para la misma tuvo el hecho de malgastar este tipo de poder durante la Guerra de Irak, Nye subraya la necesidad de utilizar conjuntamente tanto del poder duro como del poder blando, con lo que quedará conformado un nuevo concepto de poder, el poder inteligenteThis fragment of Professor´s Nye famous book introduces the concept and the repercussions of the soft power. Defined as “the ability to get what you want through attraction rather than coercion or payments”, it is of great relevance for the foreign policy of the United States. After exposing the different American foreign policy traditions and the negative consequences of the waste of this kind of power during the Iraq War, Nye underlines the need of using hard power as well as soft power, shaping a new concept of power, the Smart Powe