Particle Accelerators

I’ve seen pictures of the massive underground circular and linear particle accelerators and watched shows on their complex construction. They appear to be a costly thing to build.
From reading about them on line all I’ve found out about them is how they work and what they do (smash atoms) and a general statement about how they are used to study the composition of matter.
So I have 4 questions about these things.

What are they hoping to find in their tests?
What have they found in their tests?
What are they hoping to use the results for?
What have they used the results for?

Is there any real use for them or are they just a means of studying matter for the sake of answering “unknown” questions about the make up of an atom?

The real use is studying matter for the sake of answering unknown questions about the makeup of an atom. Are you saying that’s not enough?

I haven’t heard any plans to use the resulting knowledge to make a better TV set, but you never know.

The point of particle physics is to probe the smallest constituents of matter. Originally that was the atom and we discovered protons and neutrons. As the energies climb higher and higher we can probe deeper (i.e. smaller) and deeper into the basic make up of the universe.

One of the great achievements of the 20th century was the Standard Model which basically describes how the all the fundamental forces (except gravity) particles of nature interact. So by probing deeper into the basic make up of the universe we better understand light, radioactive decay, stellar evolution, particle interaction and a host of other things.

It is basic, fundamental physics though. The purpose is to achieve a more accurate picture of the universe and how it behaves. It opens up newer avenues for applied physics to move down, but practical applications are not its focus.

Another use is to generate intense beams of light (synchrotron radiation). It’s by far the most powerful X-ray source available. Synchrotron beams are used for medical research (e.g. extremely high-resolution X-ray images of tissue samples), biochemistry (e.g. analyzing protein structures), material science (e.g. analyzing crystal structures), testing X-ray optics and detectors, and many other fields that benefit from having a bright X-ray source. I’m an astronomer and I’ve used such facilities to test astronomical X-ray detectors.

Such experiments used to be a fringe benefit of accelerators built for particle physics. But it’s so useful that new accelerators are built for the express purpose of genrating synchrotron radiation.

Semi-practical application: the laser-wakefield accelerator. I’d forgotten about these. It basically puts a km long high energy source on a tabletop. What that will allow people to do likely can’t be imagined right now.

Applications deriving from the frontiers of physics typically lag a few decades behind the raw discoveries. Technology transfer happens somewhat more quickly. Present particle physics experiments have as little obvious practical use as hundreds of other experiments over the past century and a half which have, in time, led to things like:

  • electricity as we know it
  • transistors (and, consequently, absolutely everything in BestBuy)
  • nuclear power / nuclear weapons
  • innumerable medical tools: X-rays, MRI, PET, CAT, radiation therapy

1990- and 2000-era neutrino detector designs are being successfully adapted (using literally the same equipment) into small scale neutron detectors for placement at border crossings. In a similar vein, our understanding (obtained in particle detectors) of the process of muon multiple scattering allows for muon radiography of vehicle contents.

The motivation for the folks working on particle physics experiments today is primarily the love of discovery. The motivation for the funding agencies is the knowledge that clever people always have and always will come up with ways to apply the knowledge gained. You can bet the farm that in 2060 your kids or grandkids will benefit from something that stemmed from these accelerator-based physics experiments.

I want my Higgs boson-based TV set!

I tried getting one of those home once, but it was too heavy to fit into my car.

That’s what happens when you drive a Toyota Tercel. You should get a Yukawa Pion–it runs on strong nuclear interaction. Or Technicolor-based t.v. instead.


Yeah, if they came up with a matter-antimatter annihilation engine, your car’s fuel tank could be the size of a peanut and never need refilling. And I mean the nutmeat, not the entire shell assembly.

Of course the engine itself would have to be huge.

Oh, and you’d need dilithium.

I have read a couple books on this subject ,but not recently. The accelerator tries to accelerate the particles near the speed of light. into other particles. After the crash they look at photos showing the tracks and relative size of the new particles.
These are interpreted. The interpretations are not always agreed upon.When the quarks were being hunted the top and bottom were therorized but no real evidence had been found. It was a real feather in ones cap to find it. Cern claimed to find the bottom ,but it required some outside agreement. Egos and trying to be first were part of the equation.