When the launch of world’s largest particle accelerator, the Large Hadron Collider (LHC) at CERN (Counseil Europeen pour la Recherche Nucleaire) on France-Switzerland border near Geneva, were announced, there were some rumours that their experiments would result in earthquakes and natural accidents, but why people were afraid of it and why it was needed to be built in the first place? and what exactly is a Particle Accelerator?
So, let’s start with common questions regarding LHC:
What is a particle accelerator? and what it does?
A particle accelerator is a machine that uses electromagnetic fields to to accelerate charged particles to very high speeds and energies and to keep them in planned path.
So, what really is the use of it?
Well, we all know the story of how Ernest Rutherford discovered Nucleus. He bombarded a foil with alpha particles and noticed there is something material in center of atom and called it nucleus. It implies that if we want to see and observe what is inside atom and then individual particles is to make them collide and and see what they break into. Thats the simplest way to study anything. You want to know what is your smartphone made of? Break it and see what is inside of it (Only if you can afford it, Do it at your own expanse).
So, a particle accelerator, accelerates subatomic particles with magnetic fields and makes them collide, and then scientist study the debris of the collision to know what they are made of.
There are hundreds of particle accelerators around the world. LHC at CERN is most commonly known. Others that are famous are at SLAC National Accelerator laboratory in Menlo Park, California and at ESRF (European Synchrotron Radiation Facility) in in Grenoble, France.
What is Large Hadron Collider? and why it is special?
Because it is the largest in the world. The bigger the electromagnetic field’s path and stronger they are, bigger the speeds can be achieved. According to some reports, LHC can accelerate particles at 99% of light-speed. LHC’s tunnel in which particles are accelerated and are collided is 27 km in length.
Why it is called “Large Hadron Collider”?
If you have studied some particle physics, you would remember something called ” Standard Model of Fundamental Particles” which contained 16 particles before 2013 and then 17 including Higgs Particle (will be discussed later), which were called the elementary particles, meaning they are indivisible.
And among those six quarks namely up, down, charm, strange, top and bottom, they combine in various configurations to make other particles like protons and neutrons and many others like Pions, Kaons etc. These combination particles are called as “Hadron” and thus the name “Large Hadron Collider” meaning it collides togather hadrons and observes its debris.
How LHC works?
LHC is a somewhat elliptical ring, in which two beams, which contain about 100 billion proton are fired in opposite direction and are propelled with the help of superconducting electromagnetic fields. These beams pass each other at some point, where some portion of beams collide while the rest stays in their circular paths. Reason they miss is because atoms are mostly empty space. Scientists monitor these collisions and study their debris in the hunt for new particles. As there are billions of collisions per second because beams collide and uncollided beams comes back to collide again, thats why there are four collision points, or collision detectors namely ATLAS, ALICE, LHC-B and CMS (Compact Muon Solenoid) where collisions are observed.
LHC is operational since 2008 and it has several findings discoveries under its belt. Some of them are listed below:
1. In 2013, CMS discovered the Higgs Boson, which was theorized by English Physicist Peter Higgs decades ago, which was added to standard model of fundamental particles. Peter Higgs then received Nobel Prize for this prediction.
2. On December 22, 2012, a new particle named bottomonium was reported.
3. On November 8, 2012, LHC reported an experiment which was seen as “golden” test in supersymmetry theories in physics.
A new LHC High luminosity upgrade is planned, which will be functional by 2026 which will provide 14 TeV collision energy to particles, further expanding the possibilities of new discoveries.
Why LHC is called as “The Big Bang Machine”?
LHC is called sometimes as the big bang machine because it was considered to be creating the conditions for the big bang, the event which led to formation of our universe and this led to widespread fear among general public that this will generate some kind of black hole or release energy that may be hazardous to earth and human population. This even led to novels, movies and TV shows ideas like in Dan Brown’s Angels and Demons, LHC creates antimatter that causes an explosion on top of Vatican City and on CW’s The Flash, an explosion in a a particle accelerator at STAR labs creates superpowered so-called metahumans. Well scientifically, above consequences cannot occur.
Real reason it is called ” Big bang machine” is because it aims to break the pigments of universe down to a point which according to theory was what spawned the big bang. Atoms breaks into subatomic particles and then those particles breakdown further and this goes on and on until that elusive point.
No matter your perception is of LHC, one must marvel at its audacity and it tells a story that if human minds work collectively for a common goal, nothing is impossible and no secret of universe is elusive.