By Chris Conway
Physics has the potential to reveal the fundamental nature of the universe. Recent theories show that neither ``common sense" nor our senses are reliable interpreters of reality.
Located in Switzerland, the Large Hadron Collider (LHC) can expand our limited understanding. It has particles collide into each other at high speeds. By observing these collisions, scientists can check if the latest theories are correct. This article will focus on the implications of the LHC for ``String Theory."
String Theory could represent the fulfillment of Albert Einstein's dream. Einstein wanted to unite the four fundamental forces under one theory. These are electromagnetism (involved with light and electrical appliances), the strong and weak nuclear force (connected to atoms) and gravity (the attractive force between objects). Though he never succeeded, the tendency for theories to apply on wider scales suggests it's a valid aim.
String Theory says that all forces and particles are made of extremely small strings. This is an attractive idea because it brings together the zoo of particles that gives physicists a headache. Just as musical strings make different sounds, vibrations of these strings make different particles such as electrons, protons, neutrons, and so forth. Think of the universe as a symphony of vibrations or a knitted jumper!
Such strings are too small for current technology to prove or disprove. Fortunately, the theory allows for the existence of larger strings, which require less energy to create. Should they exist, the high-energy collisions of the LHC present the best chance to find them. Possible confirmation of strings would be tremendous as the theory states they constitute the smallest building block of matter. However, String Theory makes an even more exciting claim.
``Common sense" tells us that we occupy four dimensions (length, width, height and time). Amazingly, the equations of String Theory require the existence of eleven dimensions (ten for space and one for time)! Where are these hidden dimensions? String Theory offers two possible answers: They are either too small or too big for us to perceive.
The LHC will again play a critical role in verifying hidden dimensions by investigating the gravity mystery. Why is gravity much weaker than the other three fundamental forces previously mentioned? When you use a magnet to pick up a paper clip from the ground, it is overcoming the gravitational pull of the entire planet! String theorists believe gravity is strong and appears weak because it leaks into these hidden dimensions. Therefore, on extremely small scales we can assess the actual power of gravity before leakage occurs.
How can the LHC resolve this issue? The high-energy environment there would be conducive to the creation of tiny black holes. Contrary to irrational claims made by some, these black holes are unstable and would disappear very quickly. Given that black holes are products of extreme gravity, their abundance in the LHC would support the idea of strong gravity. This in turn would present strong evidence for multiple dimensions.
Let's not forget that the ideas of String Theory have not been experimentally confirmed. This is why the findings of the LHC are so important to interested physicists and lay people. Should the theory be disproved, physicists can move on to test new theories. If the theory is proved, it will raise our conception of reality to the next level.
Confirmation of String Theory would also bridge the divide between general relativity (theory relevant to big things) with quantum mechanics (theory relevant to small things). Such a fusion would allow physicists to comprehend objects that are both big and small, such as black holes and the seed that expanded into the universe.
Next time ― what can the LHC tell us about the origins and composition of the universe?
The writer is a teacher at Ulsan Institute of Foreign Language Education. He can be reached at chrisconway007@yahoo.co.uk.