The first particles have been injected into the biggest atom smasher on the planet, marking the start of the countdown to probing the secrets of the universe. Scientists are pushing ahead with powering up the machine, shrugging off speculative fears that it could destroy all life on Earth by sucking it into a black hole.

The most powerful atom-smasher ever built could make some bizarre discoveries, such as invisible matter or extra dimensions in space, after it is switched on in August. But some critics fear the Large Hadron Collider could exceed physicists' wildest conjectures: Will it spawn a black hole that could swallow Earth?

Our planet is not at risk from the world's most powerful particle physics experiment, a report has concluded. The document addresses fears that the Large Hadron Collider is so energetic, it could have unforeseen consequences.

When the world's most powerful particle accelerator starts up later this year, exotic new particles may offer a glimpse of the existence and shapes of extra dimensions. Researchers from the University of Wisconsin-Madison and the University of California-Berkeley say that the telltale signatures left by a new class of particles could distinguish between possible shapes of the extra spatial dimensions predicted by string theory.

A fireball created in a US particle accelerator has the characteristics of a black hole, a physicist has said.

Physicists met to discuss plans to link supercomputing centers worldwide into a massive global grid that will help process super collider data.

The international high-energy physics community is campaigning for a 30-kilometer long, internationally funded, particle accelerator that could "offer a precise tool to explore some of the most important unanswered questions in physics."

James Blodgett has setup a new website to discuss the risks that upcoming high energy collider experiments might destroy the earth or even the universe.

Gregg Easterbrook offers a skeptical guide to the most common doomsday scenarios.

Scientists are becoming increasingly confident that they will be able to create black holes on demand, in quantity, using the new atom-smashers due to come online in the next five years. Some estimates suggest that the new Large Hadron Collider (LHC) will be able to create an average of one black hole each second.