High Energy Physics,horizons*

The previous sessions have borne witness to the fact &at high energy accelerator and storage ring technology is a.subject of continuing vitality. Nothing dramatizes this more convincingly than the chart (Fig. 1) which shows the growth in energy of the world’s accelerators in time. If one includes in this chart the equivalent laboratory energy of existing and projected colliding beam storage rings then the chart reflects an exponential increase starting from 1930 risiug in laboratory energy at the rate of approximately one decade every six years. Clearly this growth cannot go on forever but if the next generation of t’super” storage rings which have been discussed during this session become reality on the approximate schedule their proponents project, then this exponential increase is maintained. This graph has many implications some good, some bad. It bears witness to the fact that as any one accelerator technology became fully exploited new ideas have produced a new and successful attack on I&e problem. One result of this pattern has been that the cost per GeV has gone down almost as dramatically as the energy has gone up. Consequently the range of investment in each new installation starting from the MeV region to the many hundred GeV covers only one, or at most two, orders of magnitude. A conclusion one can draw from this’fact is that no region of the world seriously participating in high energy physics can affort to stand still because otherwise one would be frozen in a situation of much less effective technology. This growth rate has many complicating implications in the present climate of fiscal constraint. While the laboratory energy increases by a bctor of 10 every six years or so, the lead time from proposal to completion of a new installation has averaged around tea years in the past. Therefore it is no surprise that laboratories which have just acquired new facilities should at the same time be worrying about the next step of innovation. This circumstance has drawn a great deal of criticism from supporting agencies and the public, but in view of the time scale shown here there is no other way unless of course there is an overall drastic sIowdown in the evoIution of this field on an international scale.