When it comes to research in experimental physics in areas that already exist, the frontiers that are usually explored are those of precision and size.

In the case of the precision frontier, the idea is to measure something more precisely than it has been done before because with greater precision there is a better chance of finding disagreement with theoretical expectations. Such disagreements (or ‘anomalies’), especially if they persist and are recognized as not being due to some errors in experiment or theoretical calculations, are the basis for thinking that there might be something new going on and may lay the foundations for some kind of breakthrough.

The other frontier is to extend the range of the parameters and in the case of high-energy physics, that means going to higher and higher energies. But this is enormously expensive. The Large Hadron Collider that was built at CERN at a cost of billions of dollars reached the existing energy limit and it resulted in the detection of the long-sought Higgs boson.

I had thought that there would be no political will to think of spending even greater amounts to built an even bigger accelerator but it appears that one is indeed being proposed.

The LHC reaches the end of its life around 2041 and Cern’s member states must decide what comes next. The frontrunner is a colossal machine called the Future Circular Collider or FCC.

According to Cern’s feasibility report, the FCC would be more than three times the size of the LHC, calling for a new 91km circular tunnel to be bored up to 400 metres underground. The machine would be built in two stages. The first, starting in the late 2040s, would collide electrons into positrons, their anti-matter partners. At some point in the 2070s, that machine would be ripped out to make way for a new collider that smashes protons at seven times the energy of the LHC. The first phase will cost an estimated 15bn Swiss francs or £14bn.

The engineering alone is ambitious, but the FCC faces wider challenges. Cern’s member states, who will vote on the project in 2028, cannot foot the whole bill, so other contributors are needed. Meanwhile, a debate is rumbling on over whether it is the best machine for making new discoveries. It is not guaranteed to answer any big questions in physics: what is the dark matter that clumps around galaxies; what is the dark energy that pushes the universe apart; why is gravity so weak; and why did matter win out over antimatter when the universe formed? With no clear prize to aim for, [the director general of CERN Mark Thompson’s] job will be harder.

When the LHC was first proposed, the size of it was astonishing. The sheer size of the new FCC machine is staggering.

This is going to be very controversial. It is likely to face opposition not just from budget-conscious politicians but also from within the science and even the physics communities. This is because all those scientists who do not work in this particular area will fear that any money allocated for this will result in squeezing the budgets of every other area of science research. This debate was very heated even during the planning of the LHC. In these days, when science budgets are being severely cut in the US, the potential for tension and conflicts within science is going to be even greater.