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An Overview: Physics Through the 1990's (1986)

Chapter: Supplement 2 - Education and Supply of Physicists

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Suggested Citation:"Supplement 2 - Education and Supply of Physicists." National Research Council. 1986. An Overview: Physics Through the 1990's. Washington, DC: The National Academies Press. doi: 10.17226/626.
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Supplement 2 Education and Supply of Physicists Numerous opportunities for major advances in physics during the coming decades are described elsewhere in this overview volume and throughout the panel reports. International cooperation and competition can be expected to continue to stimulate the scientific enterprise, but maintenance of a U.S. leadership role in physics is essential to the vitality of physics everywhere and to the technological strength of our nation. Such leadership is possible only with a strong base of highly educated scientists. This supplement describes the changing patterns in the supply and employment of physicists in the United States and poses questions concerning our manpower resources in the future. The events of the past two decades have left us with an aging academic community, a smaller core of physicists regularly engaged in basic research, and a continuing high outflow of physics Ph.D.s to related areas of science and engineering. Although graduate enrollments in physics began to increase in the 1980s, most of the increase reflected the rapid growth of the foreign-student component. The number of U.S. physics graduate students has continued to decline slowly. The decline, coupled with a low retention of Ph.D.s in physics, leads us to expect only minor increases in the physics labor force in the near future. By the middle to late 1990s, the retirement rate is expected to increase significantly as a result of the large number of entries in the 1960s. The supply of entrants into the physics labor force could decline at the very time that retirements will be most numerous. Although pleas for a return to the high production levels of graduates during the late 1960s would be inappropriate, concern over the effects of a potentially diminishing labor force is warranted. In the following sections we describe the major features of the current situation and the issues on which they focus attention, including an analysis of the contributory events of the past two decades. We conclude the supplement 91

92 PHYSICS THROUGH THE 1990s: AN OVERVIEW by projecting the contour of physics manpower in the coming decades. Because the production of highly skilled physicists is a long-term process calling for extensive lead time, immediate consideration of such projections takes on added importance. PRODUCING TRAINED YOUNG PHYSICISTS HISTORICAL OVERVIEW Initial decisions affecting (or precluding) later careers in science are typically made in the early teen years. Secondary-school students who fail to take the advanced science and mathematics sequence are unlikely to take college-level science courses, and they are even less likely to major in physics. In the United States, however, less than half of secondary-school students take more than 2 years of science and mathematics. A much smaller proportion (less than 20 percent of 1980 graduating seniors) is exposed to physics. The value of even that limited exposure is being questioned in light of the shortage of qualified mathematics and science teachers. Many of the competent teachers have left for more prestigious and remunerative jobs, while the number of new science teachers being trained has declined severely. The deteriorating condition of precollege science and mathematics education has long been of concern to the physics community, and by the 1980s it had become a national concern.* The crisis in secondary-school education raises serious questions about the future scientific literacy of the nation and the development of the needed pool of potential scientists. Training professional physicists is a lengthy and selective process. Only a small fraction of the students exposed to physics at the college level major in physics. A still smaller fraction undertake graduate study and emerge 4 to 9 years later with a Ph.D. in physics. This core of Ph.D. physicists is a precious national resource. It is the group that must sustain our physics research effort; train the next generation of students, researchers, and teachers; and provide the talent for a wide variety of related scientific and engineering disciplines. The number of physics graduate students soared during the 1960s, following a rekindled interest in the physical sciences brought on by Sputnik and increased federal support. More than 1500 Ph.D.s were graduated in each of the last 3 years of the decade. In 1969-1970, Ph.D. production peaked at 1545 (Figure S2. 1), a 148 percent increase since the beginning of the decade.) * See, for example, A Nation at Risk: The Imperative for Educational Reform, The National Commission on Excellence in Education (1983), and Educating Americans for the 21st Century, The National Science Board Commission on Precollege Education in Mathematics, Science and Technology (National Science Foundation, Washington, D.C., 1983). t Data are derived from American Institute of Physics' (AIP's) annual departmental surveys of enrollments and degrees. Figures may differ slightly from those obtained from other sources, e.g., National Academy of Sciences and National Science Foundation. Nearly 100 percent of physics departments have traditionally responded to these annual AIP surveys. Data missing from some departments are estimated on the basis of the previous year's responses.

EDUCATION AND SUPPLY OF PHYSICISTS 93 1400 UJ z 1100 CI: 1 000 m 700 600 1500 _ 1300 1200 _ 900 _ 800 _ /1111 1 961 1965 1969 1 973 1 977 1981 ACADEMIC YEAR FIG U RE S2. I Physics doctoral degrees granted, 1961-1983. Employment opportunities in academe were bright during the early 1960s because of the upsurge in student enrollments and the increased federal grant money for research. The number of positions in research and teaching expanded rapidly, and new physics Ph.D.s quickly filled the assistant professor ranks. Although it was difficult to believe at the time, such a high rate of expansion could hardly be expected to continue indefinitely.* It did not. Toward the end of the decade, when the physics enrollment was approaching its peak size, harbingers of difficulties ahead began to appear. Federal funding for basic research slowed with the nation's heightened involvement in the * Physics Survey Committee, Physics: Survey and Outlook, National Academy of Sciences National Research Council, Washington, D.C., 1966.

94 PHYSICS THROUGH THE 1990s: AN OVERVIEW Vietnam War.* The Mansfield Amendment had the effect of curbing basic research support from many of the traditional mission agencies, and the National Science Foundation was unable to assume the full burden of support. New academic positions diminished in number, and the economy (which had not been particularly robust) presented only limited alternative job opportuni- ties. By the time the large new classes of physics Ph.D.s entered the employment marketplace at the beginning of the 1970s, traditional opportunities had nearly vanished. Many Ph.D.s took temporary postdoctoral positions, hoping to wait out the economic doldrums. Despite the unfavorable job market, most new physics Ph.D. s found science-related positions, although not necessarily long-term jobs in physics research. The dashing of expectations for traditional university research careers in the first half of the 1970s brought bitterness to some and chanced the perspectives of manY.T As the decade progressed . . ~ . . . . . . . . . . . . Industrial employment grew In physics and In related science and eng~neenng areas. Physics Ph.D.s adjusted their expectations and pursued the changing opportunities. As new employment avenues began to expand in the 1970s, degree produc- tion in physics plummeted. Bachelor's degrees had already begun to decline by the late 1960s; Ph.D.s soon followed, dropping from over 1500 at the beginning of the 1970s to little more than 900 by the end of the decade. This reaction to the difficult market conditions of the early 1970s eased the employment situation for the new Ph.D.s emerging in the middle to late 1970s. Job offers increased; by 1980, only 2 percent of the Ph.D.s lacked job offers at the time their degrees were granted, compared with 25 percent at the start of the decade. While this steep decline in physics degree production was taking place, the number of postsecondary-school students was rapidly growing. The children of the extended demographic baby boom of the l950s, encouraged by the availability of educational loans, filled the colleges in the 1970s. Many students entered the biological and social sciences, but few majored in physics. Ph.D.s in physics, in fact, represented only 7 percent of all natural science and engineering doctorates in the late 1970s, down from the 11 percent figure that had been relatively constant for several decades. Although such a shift augured well for the competitive employment position of new physics-degree holders, it raised concern about the availability of future human resources in physics. The one area where employment opportunities for new physics Ph.D.s had not altered by the beginning of the 1980s was academe. The young physicists who had swelled the ranks of assistant professors in the 1960s were now tenured, but they were far from retirement. In 1980, assistant professors represented only 14 percent of academic physics staffs, a lower percentage than in any other scientific discipline. With few senior positions opening, many of these assistant professors could not be awarded tenure. The effect of this "missing generation" of young academics is reflected in the dramatic aging of university physics department staffs from a median age of 38 in 1973 to 44 in 1981. * See Supplement 3 on research funding for further details. ~ The Transition in Physics Doctoral Employment, 1960-1990 (American Physical Society, 1979).

EDUCATION AND SUPPLY OF PHYSICISTS 95 This brief history of the past two decades provides a background for discussing the human-resource issues facing physics in the 1980s. ENROLLMENTS AND DEGREES: THE PROLONGED DECLINE As noted, physics Ph.D. production declined rapidly throughout the 1970s, dropping to the low 900s by 1980, and hovering at that level since. In 1980 the first-year physics graduate student enrollment was 2439, down 44 percent from the middle 1960s. It appeared that graduate physics enrollments had finally bottomed out; 1981 saw the first rise in enrollments in 15 years. While it would be another 5 to 6 years before these increases could be reflected in Ph.D. production, an eventual turnaround seemed on the horizon. U.S. and Foreign Composition Detailed analysis of enrollments, however, pointed up a new phenomenon. In the 1970s foreign students constituted about one fifth of physics graduate students, or about 600 new foreign nationals a year. As the total number of first-year physics graduate students reached its nadir in 1980 and then began to rise, a major change in the citizenship composition of these students was also occurring. By 1983, more than 1000 of the first-year physics graduate students were foreign citizens~O percent of that entering class. U.S. university physics departments were drawing students from many countries, providing particular opportunities for students from the less-developed countries in Asia and the Middle East. This influx of foreign students, however, clouded another trend. The decline in first-year graduate enrollment of U.S. citizens in physics did not, in fact, bottom out in 1980; it continued through 1983 (Figure S2.2~. If there had previously been concern about the availability of highly trained physics manpower in the United States, these data only heightened it. What lay behind the continued decline in U.S. graduate students? Although there were few academic opportunities, the general employment situation for new physics Ph.D.s was healthy. Job offers were plentiful, and starting salaries were high. Were the front-page breakthroughs in the biosciences, the new technology excitement of computer science, and the financial rewards of the professions drawing bright potential physics students away? Such changes in student career directions could have a major impact on a comparatively small area of concentration like physics. In 1984, the number of first-year foreign graduate students continued to increase; however, U.S. enrollments for the first time in many years increased even more. Although 1985 saw a flattening of these trends, the changes in what had been a long decline in U.S. first-year enrollments provided at least a temporary sense of relief to the physics community. Women and Minorities Despite intensified efforts on the part of professional societies in physics and of related women's groups, the approximately 3 percent of Ph.D. physicists that women still represent (Figure S2.3) is the lowest among the major scientific areas. New physics Ph.D.s do include a higher proportion of.women, but the actual number of doctorates awarded to women in the United States

96 PHYSICS THROUGH THE 1990s: AN OVERVIEW 3500 3000 2500 `r 2000 m - - Z 1 500 1000 500 o 1971 1973 1975 I 1 1 1 1 U.S. Citizenship 1 1 1977 1979 1981 1983 1985 ACADEMIC YEAR FIGURE S2.2 First-year graduate physics students by citizenship, 1971-1983. has not changed since the middle 1970s approximately 65 per year. In most science and engineering areas, increased degree production has reflected the growing participation of women. Enrollment of women in the formerly male bastions of engineering and computer science, particularly at the undergradu- ate level, has skyrocketed. The same cannot be said of physics. The reasons for the continuing underrepresentation of women in physics are not yet fully understood. Women constitute the major untapped future re- source for the physical sciences and engineering; nowhere is that more true than in physics. Whether one is thinking of the future development of the field or of equal access by all segments of the population, the minimal participation of women in physics remains a major concern. If the representation of women in physics is low, the representation of indigenous U.S. minorities, e.g., blacks, Puerto Ricans, Mexican Americans, and Native American Indians, is even lower. They make up less than 1 percent of the physics labor force; total production at all degree levels remains low.

EDUCATION AND SUPPLY OF PHYSICISTS 97 22 20 18 16 14 12 LO 10 C: 8 6 4 2 - - Biology ~ / - - - Earth & Environmental Sciences ~ - All Science & Engineering Fields - Mathematics Chem istry - Physics & Astronomy 1 1 1 1 1 973 1 975 1977 1 979 1 981 1 983 YEAR FIGURE S2.3 Women as a proportion of all doctoral scientists by selected fields, 1973-1983. Full representation is found only among U.S. Orientals. This is a problem shared throughout the science and engineering community. Some inroads have been made at the bachelor's level in such fields as engineering and chemistry and, probably, computer science. Physics, with few such direct entry-level positions, has seen no increase in the representation of indigenous minorities. If anything, the number may be decreasing.

98 PHYSICS THROUGH THE I990s: AN OVERVIEW TABLE S2.1 Number of Physics Doctorates by Subfield, 1969-1983 Academic Year Subfield 1969 1970 1971 1972 1973 1974 197S 1976 1977 1978 1979 1980 1981 1982 1983 Solid State 360 402 442 393 400 351 319 282 257 243 243 202 250 235 221 Elementary 220 258 278 198 222 148 124 128 138 135 119 117 117 118 136 Particle Nuclear 188 212 227 234 182 144 130 96 93 77 103 73 62 53 90 Atomic and Molecular 127 152 124 150 122 120 138 116 105 88 72 69 65 96 71 Plasmas 61 85 86 93 74 57 53 75 72 68 62 59 65 69 72 Astrophysics 55 63 54 66 67 77 71 72 57 74 57 69 59 50 65 Optics 16 30 25 3 1 33 26 33 50 3 1 33 46 43 54 42 50 Acoustics 11 22 20 20 15 11 12 9 12 14 13 23 13 11 14 Fluids 24 21 20 27 28 22 22 20 14 13 14 15 14 13 15 Other 345 364 405 360 383 322 331 309 307 257 321 263 266 274 258 1407 1609 1681 1572 1526 1278 1233 1 157 1086 1002 1050 933 965 961 992 SOURCE: NAS. ~ Between 1969 and 1982, this category was listed as Nuclear Structure. In 1983, it was changed to Nuclear Physics, which it was felt more accurately described the scope of the subfield. This change to a broader definition is probably responsible for the apparent upswing in degree production in this subfield between 1982 and 1983. The earlier dramatic decline in degree production in the late 1970s and early 1980s reflected only degrees awarded in nuclear structure, an underestimate of the total number produced in nuclear physics. Declining Enrollments in Physics Subfields The steep decline in physics Ph.D. production affected most of the major subfields of physics during the 1970s (Table S2.1~. Degrees in solid-state physics; elementary-particle physics; nuclear physics; and atomic, molecular, and optical physics had dropped to less than half of their peak early 1970s levels by the beginning of the following decade. They have remained relatively stable since. Any continued erosion in subfield degree production may present threats to the research vitality of an area and could be a cause for concern in the entire physics community. While degrees in plasma physics and astrophysics also declined from their peaks in the early 1970s, the drops were not so precipitous. Only in optics, one of the most applied of the major physics subfields could a countertrend be observed; here, Ph.D. production doubled between 1971 and 1981. A similar increase was occurring in medical physics, although this area was not yet being monitored by the National Research Council. RETENTION OF PHYSICS DEGREE HOLDER~MOBILITY Physics has traditionally trained practitioners for other disciplines: at the bachelor's level for engineering, at the masters level for.education and

ED UCA TI ON AND S UPP L Y OF PH YSI CIS TS 99 business, and at the Ph.D. level for a multitude of developing science and engineering areas. More than any other scientific discipline, physics has sent its Ph.D.s to related disciplines to serve society's growing technological needs. Much of the outward mobility of physics Ph.D.s has been into engineering and interdisciplinary areas such as geophysics, materials research, and bio- physics; but Ph.D. physicists also work in areas ranging from chemistry to the biosciences. Some of this mobility occurred within academe where physicists teach and conduct basic research in related science and engineering depart- ments. Most of it, however, occurred in the industrial sphere where applica- tions of physics research move easily across disciplinary barriers. While patterns of high outward mobility have been typical of physics and have actually alleviated potential problems during periods of surplus, one must re-examine their impact during periods of dwindling supply. In the early 1970s, 30 percent of Ph.D. physicists were working outside of physics. As the economic support for physics research declined and alternative opportunities arose, the proportion increased to approximately 40 percent. Since the middle 1970s, employment opportunities in physics have improved; nevertheless, physics continues to provide needed skilled resources to other science and engineering areas at the same high rate. As the 1980s began, a large number of Ph.D. physicists were moving into the growing areas of systems and electronic engineering and computer science. In 1981, 27,000 physics Ph.D.s were employed in the United States; 10,400 of them were working in nonphysics areas. Physics will certainly continue to provide many of its well-trained research- ers to the new, growing areas of the future. Concern, however, may arise when this high level of outward mobility is coupled with a decline in the supply of new physics degree recipients the dominant pattern of the past decade. AN AGING COMMUNITY The declining physics Ph.D. production during the 1970s, coupled with the departure of many young Ph.D.s to neighboring science and engineering areas, has produced an aging of the physics community over the past decade. This aging was most marked in academe where opportunities for young physics faculty remained blocked by the highly tenured-in staff at most physics departments and the lack of funds for staff expansion (Figure S2.41. In the early 1970s, physics faculties, at a median age of 38, may have been unusually young, reflecting the heavy influx of new Ph.D.s during the previous decade. This was certainly not true in 1981, by which time the academic physics community had aged by an average of 6 years to 44. They were not only the oldest group within the physics community but they were also older than academics in other science disciplines (Table S2.2~. Most of the full professors who by 1981 made up the majority of the academic physics staffs were still more than a decade away from retirement. Thus, additional aging is expected in academe through the 1980s, although some expansion of opportu- nities appears likely as retirements slowly begin to increase. The universities provide the major stimulus for the important basic research that drives the development of the entire field. An aging faculty raises a number of issues: the most obvious is the lack of academic opportunities for young

100 PHYSICS THROUGH THE ~990.s: AN OVERVIEW 45 44 43 42 LLJ By LL ~ 40 41 39 38 37 OIL University ;~ ~~_~/ /~ / Federally Funded R&D Centers 1 1 1 1 1973 1975 1977 YEAR /Government ,, I nd ustry 1979 1981 FIGURE S2.4 Changing median age of physicists by employment sector, 1973-1981. physics Ph.D.s.* At the predoctoral, postdoctoral, and junior faculty levels young physicists have traditionally made creative contributions to forefront basic research in physics." The full effect of these contributions frequently does not appear for several decades; thus, many of the accolades of the 1980s have their source in the research activities of young physicists in the halcyon decade of the late l950s and early 1960s. The relative absence of young researchers from today's academic scene is a cause for concern about our ability to pursue effectively the opportunities that lie ahead in physics. Physicists have also aged in other areas of research. Except for the in-house government laboratories where funding cutbacks had been particularly large however, such aging was minimal in contrast to that observed in the univer- * Physics Careers, Employment and Education, AIP Conference Proceedings Num- ber 39 (1978). ~ See, for example, J. R. Cole and S. Cole, Social Stratification in Science (University of Chicago Press, Chicago, 1973), pp. 107-109; R. K. Merton, The Sociology of Science (University of Chicago Press, Chicago, 1973).

EDUCATION AND SUPPLY OF PHYSICISTS 101 TABLE S2.2 Age Distribution of Full-Time Employed Ph.D. Faculty Members by Selected Departments, Spring 1980 Age (Percentage) Under Over Field 30 30-39 40-49 50 All Fields 5 33 32 30 Physics 2 25 38 35 Chemistry 4 30 34 31 . . . . ~ ng~neenng 6 28 36 29 Computer Science 12 43 26 18 Biological Science 3 35 29 33 SOURCE: National Science Foundation. sities. In fact, the median age of the population of physicists employed in industry decreased during the 1970s as young physicists sought out new avenues of employment both within and outside physics. CHANGING PATTERNS OF EMPLOYMENT Patterns of physics employment have undergone major changes in the past decade. In the early 1970s, half of all physics Ph.D.s were academically employed. By 1981, the proportion had dropped to about 40 percent. Academic growth in physics during the decade was sluggish, and teaching staffs actually declined in size through 1979. Employment of physics Ph.D.s in industry, on the other hand, burgeoned from under 5000 Ph.D.s in 1973 to more than 8500 in 1981, representing in the latter year nearly one third of all employed physics Ph.D.s. The steady growth in industrial employment of physicists reflected the favorable climate in that sector as well as the closing of academic doors. Although some of these new industrial opportunities were in physics itself, the areas of highest growth were in related sciences and engineering. The physicists who pursued these open- ings were, in general, primarily involved in development and design, and secondarily in applied research. Basic research has generally played a minor role in industrial employment. The proportion of industrially employed Ph.D.s engaged in basic research continued to decline over the period, falling to below 10 percent by the end of the 1970s. Employment in the national laboratories, which had remained virtually unchanged during the otherwise expanding 1960s, increased steadily through the 1970s.* These laboratories offered special opportunities, in addition to * National laboratories, such as Brookhaven and Fermi Laboratories, are completely funded by the federal government but are administered by universities, industry, and nonprofit groups.

102 PHYSICS THROUGH THE 1990s: AN OVERVIEW providing a home for some of the basic physics research that had traditionally been carried out in the universities. However, the major increases occurred in the areas of applied research, as the national laboratories took on more diversified missions. In fact, by the beginning of the 1980s, a shift in emphasis at these laboratories from basic to applied research had occurred. Employment at in-house government laboratories showed only minimal growth throughout the decade. These changing patterns of employment, particularly in the industrial sphere, allowed the absorption into the economy of the unusually large number of new physics Ph.D.s who made their appearance in the marketplace during the early 1970s. These Ph.D.s were not always doing what has been tradition- ally termed physics, but relatively few of them experienced any prolonged unemployment. In 1970, when Physics in Perspective was being developed, in the midst of a period of increasing economic hardship, the National Academy of Sciences report* noted: The 1970's have begun with recognition of a critical employment situation and the realization that the traditional patterns of employment in physics are changing....If physicists understand the nature of this change, are flexible in their attitudes, and will undertake careers not only in physics but in related disciplines and specialties that also offer challenging problems, the outlook for the future could be more encouraging than was first assumed. Physics Ph.D.s appear to have followed this dictum well. The entry of young physicists into the growing areas of applied research and technology provided an important stimulus for the development of a multitude of exciting new applications of physics research, from telecommunications through medicine. Basic physics research did not enjoy the same healthy expansion, although a core of dedicated researchers did manage to weather the vagaries of an uncertain decade and continued to carve out new avenues of exploration at the forefront of physics. If basic research is to remain vital through the rest of the twentieth century, it is important to guard against any further erosion in this dwindled pool of human resources and to encourage the infusion of new talent. PROJECTIONS Projections of demand and supply are crucial to any understanding of future balances in scientific manpower. These projections are an attempt to portray what is most likely to happen to the physics labor force under different assumptions regarding expected changes in demand and supply. The projects should not be treated as predictions but rather as probable outcomes under given scenarios. Table S2.3 summarizes the critical parameters of the demand and supply models. * Physics Survey Committee, Physics in Perspective (National Academy of Sciences, Washington, D.C.,1972), Vol. I, p. 856.

EDUCATION AND SUPPLY OF PHYSICISTS 103 TABLE S2.3 Parameters in Demand and Supply Scenarios Parameters in Demand Scenarios Demand for physicists in universities and colleges Openings, no growth Death and retirement: age structure Outmobility from academe Patterns of replacement Service course loads and demographics: future enrollments Promotion rates Age and tenure status of new hirees Demand for physicists in industry, government, and federal laboratories Openings due to replacement Death and retirement Outmobility from physics Openings due to growth Economic growth, R&D, and defense spending Parameters ir' Supply Scenarios Physics Ph.D. production Demographic age factors and patterns of enrollment in higher education Perception of technological opportunities and choice of major Retention in the educational system Entry of foreign graduate students Available supply of new physics Ph.D.s Net migration of foreign nationals Immediate outmobility to other fields Demand Projections The demand for Ph.D. physicists in the future involves both replacements for current positions and growth, both directly in physics and indirectly in related disciplines. Because the expected demand scenarios in academe and outside it are quite different, they will be treated separately. Scenarios cover the period 1981-2001.* Estimated figures are presented for cumulative S-year periods to minimize unpredictable year-by-year fluctuations. ACADEME The academic employment of Ph.D. physicists has undergone tumultuous changes during the past two decades. Few labor force analysts writing during * The NAS biennial surveys have been used both to establish the employment patterns of physicists in the base year 1981 and to estimate mobility rates. 1981 is the last year for which data from the NAS biennial surveys are available.

104 PHYSICS THROUGH THE 1990s: AN OVERVIEW the expansionary period of the 1960s envisaged the tight academic market that would dominate the physics scene throughout the 1970s and into the 1980s.* These abrupt changes have produced a unique age structure: in 1981, 40 percent of university physics faculty were over 50 years old, while another 40 percent were between the ages of 40 and 49. This middle-aged "bulge'' has a major effect on any projections of future academic openings. Death, retirement, outmobility, and promotion rates take on added impor- tance when such large numbers of individuals are concentrated in the older age groups. We are assuming constant age-specific death rates for our academic professorial, based on current TIAA-CREF mortality schedules for males.T However, while the age-specific death rates remain constant, the numbers of probable deaths and potential openings will escalate as the middle-aged bulge of 1981 ages further. Retirement practices are not so clear-cut. The laws deferring mandatory retirement to age 70 were extended to academe in 1982. However, TIAA- CREF officials do not yet see any evidence of a further shift toward delayed retirement. If anything, they see some increased tendency for academics to seek early retirement. Thus our model allows for some early retirement and for half of the physics faculty members still working at age 65 to remain employed beyond that age. The combined effects of death and retirement should thus bring a dramatic increase in university employment opportunities in the l990s. Academic positions can also be freed by mobility. However, few tenured older faculty have left academe in recent years, and, conversely, not many senior-level physicists have been drawn into academe from industry or Government. Movement into and out calf academe hv vounner researchers on O , , ~ ~ , _ . . . . . . . . . . .. . . the other hand, Is an elastic and volatile phenomenon closely related to promotion rates and the availability of permanent senior positions. While American Association of University Professors rules set maximum time periods for which one can remain in untenured positions, they do not establish minimum times. If shortages develop, promotion policies are perhaps the most manipulable in the system. The model focuses on expected future openings in the senior ranks as the best indicator of long-term employment opportunities. In addition to replacement needs, academic openings can result from growth. Total faculty demand is, we believe, more tied to service course loads than to basic research needs. By the mid-199Os, the 18- to 24-year-old age group, from which college students are traditionally drawn, will decline by over 20 percent. How many of them will attend college and take physics is, of course, the central issue. If tomorrow's students continue to need a strong technological background, then it is unlikely that enrollments in traditional *Alan Cartter was less sanguine than many of his colleagues about the continuing expansionary needs of the future, but his voice was not the dominant one at the time. t TIAA-CREF is the retirement annuity fund of the great majority of academics. Thus, their mortality schedules are most appropriate for use here. They will also be used when dealing with nonacademic physicists, since general mortality schedules would indicate death rates abnormally high for professional workers. In a community that is 95 percent male, the dependency on male death-rate schedules should not need comment.

EDUCATION AND SUPPLY OF PHYSICISTS 105 science areas such as physics would suffer as precipitous a decline. However, it is questionable whether they would move so counter to the overall expected decline in student bodies as to produce a demand for faculty growth. Thus, the following scenarios assume that there will be no real growth in academic physics faculties through most of the remainder of the century. DEMAND SCENARIOS UNIVERSITIES Our projections for university physics demand involve the following three major scenarios. In each scenario, replacement positions refer to existing senior positions vacated through death, retirement, and mobility out of academe. · All replacement positions are filled. · 10 percent of replacement positions become unavailable. · 20 percent of replacement positions become unavailable. All three scenarios recognize the expected decline in number of traditional university students in the late 1980s and 1990s and incorporate some countervailing swing toward increased demand for service courses in physics and other hard sciences. We believe that the second scenario, which assumes a moderate shift toward a more science-oriented student body, is the most likely. It should be recognized that any cuts in physics faculty will hit some institutions harder than others. Under the three replacement scenarios, the median age of the university physics professorial 44 in 1981- can be expected to continue to climb by an additional 4 to 6 years through the early 1990s, peaking at somewhat over 50. Thereafter, a rapid decline in median age is expected as staff from the middle-aged bulge of 1981 begin to retire and young academics fill out the professorial ranks. Figure S2.5 illustrates the probable ranges in future median ages based on extrapolations from past hiring and promotion practices. By 2001, professors under 40 will increase to between one quarter and one third of the total physics staff, not so high a proportion as was found in the early 1970s but a more substantial base than is currently observed. DEMAND SCENARIOS~-YEAR COLLEGES Physics faculties at the 4-year colleges are considerably smaller in number, and their age structure is notably younger, than are their counterparts in the universities. Possible openings due to death and retirement through 2001 are thus relatively limited. We expect the declining number of traditional college- age students enrolling by the 1990s to have a dramatic effect on the physics programs at the 4-year colleges, many of which are even now experiencing financial difficulties. We present three possible scenarios, ranging from a severe staff reduction of 30 percent to a more modest one of 10 percent. Technological opportunities of the future and the relevance of a solid physics background may pull college students into physics courses at a higher rate than currently observed.

106 PHYSICS THROUGH THE 1990s: AN OVERVIEW 53 51 111 a: 49 47 45 F - l Best Estimate J / 1 , , 1 1981 1 986 1991 1996 2001 YEAR FIGURE S2.5 Projected median age of university physics professorial at S-year intervals, 1981-2001. However, to achieve only minor staff reductions, physics departments at 4-year colleges will need to recruit more nontraditional students. The accompanying tables for universities (Table S2.4) and 4-year colleges (Table S2.5) indicate the expected academic openings between 1981 and 2001 under the major scenarios outlined above. According to our intermediate scenario, tenured academic openings will increase steadily, swelling from 750 for the first 5-year interval (1981-1986), to nearly 1200 in 1996-2001. Whether new physicists will be available to fill these openings will be addressed later. DEMAND SCENARIOS INDUSTRIAL AND OTHER NONACADEMIC SECTORS Opportunities for physicists over the coming decade will derive prirnanly from openings in industry, government laboratories, and nonprofit organlza- tions, where 60 percent of Ph.D. physicists are currently employed. About half of these physics Ph.D.s are working directly in physics. Since only 20 percent of these physicists were over the age of 50 in 1981, death and retirement will not be major sources of openings during the rest of the century. Most analysts, however, project some growth, in contrast to the projections for academe. Highest growth is expected among small consulting

EDUCATION AND SUPPL Y OF PHYSICISTS 107 TABLE S2.4 Projected Number of Physics Openings in Universities Resulting from Death and Retirement of Senior Staff, 1981-2001a Academic Years 1981- 1986- 1991- 1996- 1986 1991 1996 2001 Total 1981- 2001 Number of Openings Due to Death and Retirement 769 911 1018 1119 3815 Number of Openings Filled by Replace- ment Scenariob Low 615 729 814 895 3053 Intermediate 692 820 916 1007 3436 High 769 911 1018 1119 3815 a Senior staff are defined as physics Ph.D.s employed as Associate or Full Professors . . . . In universities. b The three scenarios: low, intermediate, and high reflect the hiring to fill 80, 90, and 100%, respectively, of senior staff openings. TABLE S2.5 Projected Number of Physics Openings in 4-Year Colleges Resulting from Death and Retirement of Senior Staff, 1981- 2001a Academic Years 1981- 1986- 1991- 1996- 1986 1991 1996 2001 Total 1981- 2001 Number of Openings Due to Death and Retirement Number of Openings Filled By Replace- ment Scenariob Low Intermediate High 114 154 243 299 39 64 89 810 53 84 103 279 456 633 87 137 168 120 190 234 a Senior staff are defined as physics Ph.D.s employed as Associate or Full Professors In 4-year colleges. b The three scenarios: high, intermediate, and low reflect the reduction of the total physics professorial in 4-year colleges by 10, 20, and 30%, respectively.

108 PHYSICS THROUGH THE 1990s: AN OVERVIEW firms and medical laboratories.* Growth is also expected in the larger elec- tronics and communications industries where many physicists are concen- trated. While federal employment is not expected to be a major source of new positions, the national laboratories should continue to provide moderate growth in employment opportunities for physicists. We will use variations around the Bureau of Labor Statistics' (BLS) intermediate projections to describe expected growth in overall physics employment outside of academe.t We pose two basic scenarios for growth in nonacademic physics employ- ment. The first scenario assumes a moderately paced economy reflecting nonacademic growth at approximately the levels that occurred during the 1973-1981 period; This growth would average 3 percent per year, which is consistent with the BLS intermediate projection for physicists through 1995. The second scenario assumes a somewhat slower growing economy, reflecting a more conservative increase in nonacademic opportunities. Demand would be above replacement but below that suggested in the preceding scenario. This growth would average 2 percent per year. Based on expectations over the long term for an increasingly technological labor market calling on sophisticated research and development skills, we believe that the moderate growth scenario is the most likely forecast. Positions opened by physicists leaving the field are also an important source of future employment. Currently the net outmobility of physicists is nearly 1.5 percent a year. If the supply of physics Ph.D.s falls short of the demand, the level of outmobility may decrease despite a strong continuing pull into other fields. Thus the model poses two levels of net outmobility: moderate outmobil- ity consistent with current levels and low outmobility of approximately 1 percent a year. Table S2.6 indicates the number of positions in physics expected to be open in the 1981-2001 period under these two basic scenarios. The potential demand for physics Ph.D.s in related areas of science and engineering is difficult to measure precisely because there is often only a fine line separating them from physics. Nevertheless, demand for physics Ph.D.s in these areas is also expected to increase in the next decade. Thus, there are several hundred potential nonphysics or interdisciplinary openings for Ph.D.s in addition to those described in the scenarios above. Supply Projections Projections of supply depend on a number of interdependent variables: the size of the age groups from which the supply is drawn, patterns of enrollments in higher education, choice of major, retention in the educational system, and career directions following receipt of the degree. Perceptions of economic and * See, for example, Industry—Occupational Employment Matrix, BLS data tape, 1980, and Problems of Small, High-Technology Firms, NSF 81-305. ~ Occupational Projections and Training Data, BLS, Spring 1984.

EDUCATION AND SUPPLY OF PHYSICISTS 109 TABLE S2.6 Employment Opportunities for Ph.D. Physicists Working in Physics Outside of Academe by Demand Scenario and S-Year Groupings, 1981-2001 Academic Years 1981- 1986- 1986 1991 1991- 1996- 1996 2001 Conservative Growth (2% per year) Low Outmobility (1% per year) Replacement 803 939 1146 1362 New Openings 757 757 757 757 Total 1560 1696 1903 2119 Moderate Outmobility (1.45% per year) Replacement 963 1103 1305 1509 New Openings 757 757 757 757 Total 1720 1860 2062 2266 Moderate Growth (3% per year) Low Outmobility (1% per year) Replacement 803 960 1188 1428 New Openings 1136 1136 1136 1136 Total 1939 2096 2324 2564 Moderate Outmobility (1.45% per year) Replacement New Openings Total 963 1136 2099 1132 1136 2268 1364 1136 2500 1600 1136 2763 occupational demand also have an erect.* Long-term projections of possible changes are of particular import for physics, where the training pipeline frequently requires more than 10 years. Potential physics Ph.D.s of the middle l990s are making their career decisions now. We will first present short-range projections for the production of Ph.D. physicists and then venture into the uncharted territory of the remainder of the twentieth century. PHYSICS PH.D. PRODUCTION Most of the new physics Ph.D.s of the late 1980s are already in the graduate school pipeline. Extrapolating from first-year graduate students at Ph.D.- * See, for example, R. Freeman, The Labor-Market for College-Trained Manpower (Harvard University Press, Cambridge, Mass., 1971); R. Freeman, `'Supply and Salary Adjustments to the Changing Science Manpower Market: Physics, 1948-1973," Ameri- can Economic Review 65:27-39 (March 1975).

1 lO PHYSICS THROUGH THE 1990s: AN OVERVIEW PhD s PRODUCED 700_ 600_ 500_ 400_ 300_ - Resorted Pioeline W ''// 1 ___I = _ US HiCh `e,gn ALL ------~'~~~foreiqn LO'V--------- ! --— Long Term Scenarios — — — — 200_ ' 1 ~ 1 ~ 1 i 1 ~ 1 ' 1 ' 1 ' 1 1 1 19 81 1983 1985 1987 1989 1991 1993 1995 1997 1999 2001 ACADEMIC YEAR FIGURE S2.6 Physics Ph.D. production by citizenship, 1981-2001. granting departments a best past-production predictor we expect 6800 physics Ph.D.s to be awarded between 1984 and 1990.* Note should be made of the projected increase in the foreign component, a reflection of the dramatic increase in first-year foreign graduate students since 1979 (Figure S2.6~. Projections of Ph.D. production through the remainder of the century involve analysis of the education pipeline leading to graduate school. The group of 18- to 24-year-old males, from which traditional undergraduate physics majors and subsequent bachelors are drawn, will have decreased by over 20 percent by 1996. However, because of the increasing emphasis on the utility of a scientific background in tomorrow's technological society. our . . . . - · · . . . . - pronaule scenario assumes a more modest Decline in bachelor s Degrees in physics of 10 percent from current levels. The assumption presupposes that steps will be taken to alleviate the currently deteriorating condition of precollege science education so that potential physics majors are not disen- chanted with science in general before even entering college. Approximately one third of recipients of bachelor's degrees in physics go on to physics graduate study. Another 15 percent of first-year physics graduate students come from other disciplines. Our model assumes that the latter relationships will remain relatively stable in the future. * Physics Ph.D. students complete their programs in 4-9 calendar years at the following rates: 3, 7.5, 14, 11, 6, and 1.3 percent, respectively. Thus, on the average, approximately 43 percent of the first-year students eventually earn their Ph.D.s. The last 2 years of the short-term projections were supplemented by extrapolations of first-year graduate students from junior majors using linear regression analysis.

EDUCATION AND SUPPLY OF PHYSICISTS 111 The participation of foreign graduate students, which has increased dramat- ically since 1979, will have an important influence on future Ph.D. production in physics. The scientific and technological needs of both developed and developing countries are expected to stay high during the remainder of the century. Our model thus assumes a growth in the number of foreign students of between 1 and 2~/: percent a year through 2001. The erect on Ph.D. production will depend on the graduate-school completion rate of these students. In the final years of the century, we project between 980 and 1100 physics Ph.D.s a year (Figure S2.7~. Under the most extreme scenario, U.S. citizens around the end of the century may become a minority among physics Ph.D. recipients. SUPPLY OF PHYSICS PH.D.S: 1981-2001 Physics Ph.D. production does not equal supply. Two major factors that reduce this pool must be taken into account: immediate outmobility from physics and the return migration of foreign degree recipients. Many physics Ph.D.s traditionally about 20 percent move into nonphysics employment within 3 years of having received their degree. This outmobility increased to 30 percent during the difficult employment market of the early and middle 1970s, and it has not shown any marked decrease since. The current high level, however, seems to be guided more by pull than by push factors. Our model assumes that the outmobility will move toward the more typical 20 percent level as basic research opportunities in physics improve during the 1990s. PhD's PRODUCED _ 1500_ 1400_ 1300_ 1200_ 1100_ 1000_ 900_ 19 71 , . . ~ - 1976 1981 1986 1991 1996 2001 ACADEMIC YEAR FIGURE S2.7 Physics Ph.D. production, 1971-2001.

112 s~ rD z o ,,C, Ct ~ ~ .— o · _ Ct ~.c U. ~ Cd o o ~o oc ._ o Ct o C', s~ ~D z _ . _ o o L~ o o o o o o o o o o ', oo ', ~ _ ~ ~ ~ o _ ~ ~ _ - , _ ~ ~ d. 1 1 1 1 1 1 1 1 1 1 o o o o o o o o o o v ~ ~ ~ cr~ oo oo ~ X ~ C~ X ox o o o o o o o o oo ~ oo ~ oo ~ X ~ oo _ ~ _ ~ _ _ ~ o ~ 5> ~ s°~ Z P~, ~ 't 3 ~ ~ ~ ~ ~ ~ v o° o° ~o ·0 E~ Z ~ ~ ~ V~ o . - C~ c) · - c~ p~ v) E-. c~ ct e s .~o- ~ ~ c c c gu "o~ ~ ~o ~ ~o o~ ~ 3 c 3 c s: ~ ~ ~ ~ ~ ° ~ ~ 0 3 ~ ° ~ ~ - ° ~, SC, ~ o ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ o _ ~ ~ _ Ct 't ;~~ o . _ o ~ D _ ~ ~ ~o 3 ~ `:: C¢ ~ O _ ~ _ ~7 ~ -0 . ~ ~ ~ _ ·_ U, . _ — C t-O4 ~ ~ ~ O ~ U'— ~ Ce C<~ C) .= ~ ~ c¢ ~ o~ ~ ~ o ~ ~ :: ~ ;:; 3 ~ ~ ~ o 'D ~ - Ct ~ CO ~ o ~ ~ "D ~ ~ ~ . Ce = V ~ C~ ~ 2C ~ .') ~ o ~ ~ ~ ~ t 3 3 ° o ~ o .= ~ V, ·= s~ aO=~30 ~ ~ 3 ,,- c, E~ ~ ~ _ o Ct s~ ~ ^ — :>., ~_ Ct

EDUCATION AND SUPPL Y OF PHYSICISTS 1 13 4250 4000_ 375= 350Q 3250_ 3000_ 27SO_ 2500_ 2 250_ 2000_ S ,..... .:-:-:-:.:: :::::. ·:-:-:-:-:- ........... ........... :::::::::: _ ::::: :-:-:-:-:- ::::: ,....... ......... .......... :-:-:-:-:- ·:-:-:-:-: ......... ........ .:.:.:,:.: :::::::::: ·:-:-:-:-: S ,.... ...... ... 1 1 1 1 1981 -1986 1986-1991 1991-1996 1996-2001 Best Estimate Demand - D Supply -S Estimate .... FIGURE S2.8 Projected demand for and supply of physicists by 5-year period, academic years 1981-2001.

114 PHYSICS THROUGH THE 1990s: AN OVERVIEW The second factor affecting the supply of new physicists is the return home of new Ph.D.s who are foreign citizens. We estimate on the basis of past experience that one half of these foreign nationals will return home, either immediately after receiving their degrees or following an ensuing postdoctoral or other temporary position. The phenomenon is sensitive to change. With the foreign component potentially approaching half of the Ph.D. production, such changes could have a major effect on the available supply. While the number of U.S. citizen physics Ph.D.s is expected to decline, the supply of foreign Ph.D.s could double by 2001 (Table S2.7). The Demand-Supply Balance Figure S2.8 illustrates the projected range of supply of new physicists and demand for Ph.D.s to work in physics. As discussed, forecasting either supply or demand involves many parameters, some unknowable. The shaded portions of the figure reflect our best estimates of the likely demand and supply levels during each of the four 5-year periods through the remainder of the century. We project a balance between likely demand and supply through 1991. Later in the 1990s, however, it appears that the supply of new physicists may not match the number of possible physics openings. If this mismatch occurs, there is likely to be increased competition among employers for well-trained physi- cists. The divergence between probable demand and supply may be even greater than we have indicated because it does not include the projected increase In employment opportunities in the many neighboring scientific and engineering areas where physicists have always made contributions of major import. CONCLUSION If the assumptions outlined in the previous pages hold over the remainder of the twentieth century, we project a precarious balance between demand and supply through the early 1990s. Beyond that, there are likely to be more opportunities than there are new physicists to fill them. There will be keen competition among disciplines for the brightest students and among employers for new Ph.D.s. Under each of our scenarios, employers of physicists are seen as becoming increasingly dependent on non-U.S. citizens. Given the large numbers, any changes in the retention of the foreign component could have a strong effect on the overall demand and supply picture. The rest of the century represents a broad span of time during which the activities of the physics community, the federal government, and industry could certainly help to alleviate any pending shortages. The excitement now inherent in physics and the current opportunities for further research are great. It would be unfortunate if an insufficient supply of qualified physicists left these Opportunities less then fully realized. Now is the time for the physics community to seriously consider means for attracting the bright students of tomorrow. As we do so, we should recognize that the largest untapped pool of potential physicists will be found among those groups underrepresented in the past.

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An Overview: Physics Through the 1990's is part of an eight-volume research assessment of the major fields of physics that reviews the developments that have taken place and highlights research opportunities. An Overview summarizes the findings of the panels discussed in the other seven volumes and addresses issues that broadly concern physics.

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