The very tiniest particles that make up all of the matter that we can’t see are being discovered by the largest single machine ever created on planet Earth. With experiments having begun again at the Large Hadron Collider operated by the European Organization for Nuclear Research, or CERN, teams of thousands of scientists are hopeful that discoveries of dark matter and antimatter may yield up important answers, perhaps in the next few months to such fundamental questions as “Why are we here?”
Since its opening in 2008, CERN’s Large Hadron Collider, or LHC for short, has been the subject of some wild fanfare by the media. Most notably, CERN’s 2012 announcement that scientists at the LHC had discovered the long-theorized Higgs boson, which many news outlets were quick to label as “the God particle.” Officials at CERN have announced that, after massive upgrades and a few year hiatus, the LHC will again be used for a group of experiments and perhaps even yield discoveries into supersymmetric particles, which would establish a new theory of physics that goes beyond the Standard Model which has been in place since the mid-1970s.
These things are important, but not all of us possess an innate knowledge of the differences between dark matter and antimatter or why those particles even matter at all. A great deal of confusion in the mainstream over the science behind these experiments has even prompted fears about the end of the world. Perhaps far more likely than that doomsday scenario is the potential for a new periodic table of the elements and a greater knowledge of highly combustible antimatter, which has been theorized as a fuel source by such physics pop culture touchstones as Star Trek. In any event, the LHC will more than likely show us the definitive future of our universe as it expands and possibly even contracts.
What Is the Large Hadron Collider and Why Collide Particles?
The LHC, which sits more than 100 meters below the ground at the Franco-Swiss border near Geneva, runs along a circular track and is 27 kilometers, or nearly 17 miles, in length. The LHC functions as a particle accelerator to collide two particles together at super high speeds, guided towards a head-on collision by a series of superconducting electromagnets. To operate in the superconducting state, the magnets must be chilled with liquid helium as they work to a temperature of -271.3?, a temperature colder than outer space. Thousands upon thousands of magnets of various types, including dipole and quadrupole, are carefully coordinated to create the highly precise conditions for colliding particles.
The LHC was strong enough in its prior state to collide particles at a speed capable of discovering the Higgs boson. Recent upgrades, however, have dramatically increased the particle accelerator’s capabilities. The superconducting magnets that are new to the machine have increased the collision energy from 8 teraelectronvolts (TeV) to 13 TeV; one teraelectronvolt is about the force of energy of a flying mosquito, but compacted down to an area no greater than an atom the denser energy becomes a much greater force. Other improvements include electrical fault protections installed on more than 10,000 electrical interconnections between the magnets and the addition of more than 100 petabytes of data storage to handle additional data generated by experiments, which can take place once every 25 nanoseconds.
Scientists are hopeful that the renovations will not only generate more information on antimatter, which can be trapped in a magnetic field and studied for its physical properties before incinerating, but dark matter as well. Antimatter and dark matter are two different things, but they are somewhat related. Antimatter particles have the same mass as normal matter particles but they have opposite charges and unique physical properties, including the tendency to become annihilated when contacted with normal matter. Antimatter was incredibly abundant when the universe began, comprising half of all matter along with dark matter and normal matter, but is almost non-existent today. Discoveries of why antimatter disappeared could answer questions about how our universe was formed. Dark matter does not give off the same gamma ray signature of antimatter and it makes up more than two-thirds of the composition of our entire universe. Normal matter, which includes everything with mass that has ever been observed by humans, makes up less than five percent of the universe, according to NASA. A greater understanding of dark matter could tell us if our universe is forever expanding or will reach a limit at which point the universe will begin to collapse back in on itself.
After the Higgs boson discovery, discoveries for proving supersymmetry and string theory seem to be the next stop for scientists. The supersymmetric model, which is theorized but has yet to be confirmed, infers that each subatomic particle that we’ve discovered has a superpartner. For instance, an electron would have a boson called a selectron (as opposed to the positron, which is the antimatter correspondent to the electron). If this scientific model is correct, a mixture of supersymmetric particles known as the neutralino could end up being discovered as the essential substance which comprises dark matter. If neutralinos, gluinos and other supersymmetric particles cannot be detected in particle collisions, scientists all over the world have to start back at square one to find the essential force that keeps galaxies from spinning apart as they move through the universe, a riddle which has stumped researchers since Einstein predicted that space could have energy as part of his theory on gravity.
However, all technologies grow obsolete, and it won’t be too long before the LHC is no longer the world’s largest machine. By 2045, China plans to build a supercollider which would be twice the size of CERN’s LHC, large enough to circle Manhattan. The supercollider would be configured to recreate the intense forces and energy that existed around the time of the Big Bang, making it even easier to chart a course for physics beyond the Standard Model.
Experiments Being Conducted at the LHC
A couple of alarms have been raised in some areas of the world inspired by fears of what could happen if these particle accelerators do find the dark matter for which they’re searching. There is a theorized link between dark matter and black holes and there are those who have questioned, like the story linked in this article’s introduction, whether particle collisions could trigger the formation of a black hole that would swallow Earth. Thankfully, using proven models and not the theoretical science attempting to be confirmed by experiments at the LHC, this is impossible. The creation of a black hole isn’t impossible, to be fair, and it would be a big step towards proving string theory physics as a working theory of everything. The principles of Hawking radiation, which are based on quantum mechanics, shows that a microscopic black hole, the only kind the LHC could create, would quickly lose its energy and dissipate. In the fraction of a second during which the black hole would exist, it could easily slip through solid layers of any physical material at the speed of light, escaping Earth without ever having sucked up a single proton.
CERN has faced other controversies regarding its experiments and some have even called into question the organization’s famed discovery of the Higgs boson. In November of last year, researchers from the Center for Cosmology and Particle Physics Phenomenology at the University of Southern Denmark reported that the data doesn’t reflect the Higgs boson particle but rather a techni-higgs particle which is not an elementary particle, unlike the theorized Higgs boson. If the particle were to be the techni-higgs and not the Higgs boson, a totally different model of subatomic physics, the Technicolor model, would be correct and string theory would be disproven.
Thousands of scientists will be engaged at the LHC over the next three years of its operation. More than 3,000 physicists from 38 different countries will contribute to the ATLAS experiment, which is focused on the study of the Higgs boson and dark matter leading to the understanding of the extra dimensions of space and the unification of fundamental forces. A Large Ion Collider Experiment, or ALICE, is an experiment involving more than 1,500 researchers looking into the effects of extreme heat, like the heat generated within our solar system’s sun, on matter of all kinds. Other experiments will make use of the Compact Muon Solenoid, a general purpose detector built around a large solenoid magnet providing different technical solutions to address questions similar to those posed by ATLAS.
There are plenty of ways that the discovery of dark matter or antimatter could greatly impact our world. Antimatter positrons have already been used for positron emission tomography (PET), a medical imaging technique used to track the progression of cancer within a patient which has been around for a few decades. There are some who theorize that dark matter could help scientists find a new form of energy that could be used here on Earth. None of this will happen soon, to be sure, but the scientific community will certainly be very focused on the world beyond known subatomic physics over the next few years.