Laser‐driven electron–positron colliders

By 1987, two very large colliding‐beam accelerators, LEP at CERN and SLC at SLAC, should be providing high‐energy physicists with 100‐GeV collisions of electrons and positrons. But what of the next generation? With the 27‐km‐circumference LEP storage ring costing about $400 million and consuming as much electrical power as a city of 150 000 souls, can one really afford to build significantly larger $e−e+$ accelerators at the turn of the next century?