How dangerous can the Switzerland Big bang experiment be if it explode ?
They’re not worried about it “exploding”. The big issue with this is, hypothetically, when blasting two particles at eachother at near the speed-of-light the physics involved could temporarily create a very small “black hole” that theoretically would not last long enough to have any effect. Some physicists believe that it will create a black hole that will not go away and slowly begin devouring matter which will increase in rate until it sucks you and me into oblivion. You probably won’t live long enough to know about it though if it got big enough to do so, so I wouldn’t worry about it.