I have a very lamans understanding of particle accelerators, one of the things I gather is that their large size allows for the particles to be accelerated to higher speeds. This can't be done easily at smaller sizes because a smaller circumference will mean a more extreme angle for the particles to bend round (apologise for probably appalling phrasing on this topic). Is this the case? If so is making progressively larger accelerators the only option or could better technologies achieve the same result? This question is prompted by hearing a statement that at some point in the future particle physics of this sort would come up against a hard limit; that limit being the circumference of the Earth itself (assuming one build an accelerator along the equator). The statement wasn't said as though this would actually happen but more illustrating the point. I've done a bit of googling but it's hard to find a resource that isn't too popsci that is accessable.