In trying to understand matter and energy, scientists have discovered four basic forces or interactions (gravity, electromagnetism, and the strong and weak nuclear interactions). The "Standard Model" of particle physics describes how dozens of fundamental particles (e.g. different types of quarks, leptons and bosons) that make up the more well-known atomic particles like protons and neutrons, and the three interactions other than gravity, "work" together.
Gravity is the odd force out, and only one of the fundamental particles, the Higgs boson, has not yet been observed. It is believed that the Higgs boson holds the key to gravity, and why it is a much weaker force than the others.
Creating the conditions where a Higgs boson (and a few other hypothetical particles and miniature black holes) can be created requires accelerating protons (which are one type of hadron) to speeds approaching that of light, and then smashing them against each other to create, in a small space and for a short time, enormous temperatures and forces such as existed at the very beginning of the universe when the particles were first forming out of energy.
And so the European Nuclear Research Centre (CERN), supported by thousands of scientists and 20 countries, has spent billions of dollars building the "Large Hadron Collider" (LHC) underground in Switzerland - an enormous, 17 mile long particle accelerator that will produce the required high velocities. It is due to open soon.
And now, at the last minute, some scientists are challenging the operation of the LHC in the European Court of Human Rights. They claim the safety of the LHC is in doubt, because it may be able to produce miniature black holes which could then begin eating the earth from the inside due to their intense gravitational pull.
CERN has produced a safety report which concludes that there is "little theoretical chance of the collider producing mini black holes that would be capable of posing a danger to the earth". Doubtless they are correct and their critics wrong, but with the earth itself at stake, one would have thought "little chance" was still a little too much.
But we all trust scientists, don't we?