String theory needs the graviton. But guess what. They would have to freely admit to gravity waves having not be proven, yet theorectially they have moved past this with the gravitons introduction. It would seem premature,:) yet this is the way of it that the mathematics have gone down this route, and boldly gone, where no one else has gone? Does not mean it is real, its just that with what Einstein has given us we have to agree on some assumptions being made and act accordingly. LISA and LIGO have been introduced to the measurement issue. If these fail to record simuatneous events hapening within the cosmo, through all its detectors, guess what? Yep it can prove really unsettling to a lot of people. But from Webber, the road had to be proven, so the quest is still on. LIsa be space mounted, would be used in accordance with LIGO detectors(earth based) for validation?