Chapter 5
Summary
This report documents the following regarding nonlinear science:
- NLS is important to a variety of future Navy technologies and related research and development efforts at NRL;
- NLS is inherently interdisciplinary and gains dramatically when researchers in different fields can recognize and exploit common nonlinear phenomena;
- NLS requires a balanced, quadripartite methodology, including modeling, analytic, computational, and experimental investigations; and
- NLS does not evolve along a straightforward, linear path from basic research to technological application but instead follows a convoluted (nonlinear) path and flourishes best in environments in which basic researchers and applied technologists are encouraged to interact and are rewarded for doing so.
The panel is pleased to note that in recent years, NRL has supported nonlinear science through the Special Project in Nonlinear Science (SPNLS). This investment has paid off handsomely, with notable successes from NRL researchers in the areas of controlling chaos, signal recognition and encryption, combustion and reactive flow studies, advanced orbital dynamics, development of novel sensors based on nonlinear materials, and many others.
It is the panel's view that the continued existence of SPNLS, or the creation of a similar repository of nonlinear expertise, is crucial to maintenance of the interactive, interdisciplinary environment required for success in nonlinear science. Although it need not be large, this core effort must involve excellent researchers and should be funded in a stable, multiyear manner. Stable support is particularly critical in nonlinear science because its inherently interdisciplinary nature makes it especially vulnerable to the give and take of internal budget battles among large, well-established, discipline-oriented groups. Well-funded and highly developed fields, such as solid-state science, can, by their very nature, generate a much larger number of publications on topics that incrementally advance their disciplines. The goal in supporting nonlinear science should be of longer range and greater scope, with the hope of repeating successes such as that of controlling chaos.
It is essential that clear guidelines be given this group regarding its mission and the measures of success. Although this report stresses the need for NRL to recognize the long-term nature of its investment in nonlinear science, it is equally important that SPNLS or its successor be evaluated and reviewed on a regular basis. The panel's suggestions for the guidelines to form both the mandate and the basis for evaluation of SPNLS follow:
- Maintenance of an internationally recognized experimental, theoretical, and computational research effort in several specific areas of nonlinear science;
- Fostering of nonlinear science within NRL, by informing the staff of relevant recent developments in nonlinear science and by germinating effective collaborations among NRL researchers in both basic and applied areas;
- Ongoing identification of specific developments in nonlinear science, such as controlling chaos, adaptive pattern recognition, and others mentioned in the previous chapters, which have a potential impact on future Navy needs and technologies, and the coordination of initial efforts to provide proof of principle for the applications of these developments; and
- Enhancement of contacts by NRL and its researchers with external centers of excellence in nonlinear science.
In reviewing the current balance of nonlinear science research at NRL, the panel felt that the computational and theoretical science and engineering efforts were of appropriate size and strength but that the experimental nonlinear science and applied mathematics efforts, although containing very strong individuals, were perhaps subcritical in staffing. Efforts to enhance these latter two areas, by selective hiring of outstanding, interactive individuals interested in contributing to the nonlinear science effort across NRL, could be of great benefit. Both to foster interactions within NRL and to enhance contacts with the external nonlinear community, it is important for SPNLS to maintain the following:
- A high-visibility, intellectually exciting program of seminars, colloquia, and conferences;
- An active program of support for joint postdoctoral research fellows, graduate student interns, and summer students; and
- An attractive environment for visits by university faculty and other non-NRL researchers, with suitable arrangements for visits ranging from a few days to a full yearlong sabbatical.
Allocation of sufficient resources to enable these programs should be a priority for NRL.
In summary, by focusing and expanding slightly its sound existing base of expertise in nonlinear science and by leveraging its investment through interactions with external centers of excellence in this area, NRL can ensure that all its researchers and ultimately the Navy will continue to receive the full intellectual and technological benefits of the ongoing revolution in our understanding of inherently nonlinear phenomena.