Written by: Yonatan Najman-Licht '24
Edited by: Abigail Li '23
In the early 20th century, Albert Einstein theorized and experimented with his “theory of relativity.” This theory added to Newton’s understanding of the universe, by arguing that the fabric of spacetime is shockingly flat until it is warped by matter. However, Einstein’s theory failed to tie in the effect of electromagnetic forces . Since the 1960s, physicists have studied a theory known as “string theory.” String theory states that our universe is made up of little “strings” of energy that vibrate at different frequencies. However, the catch with this theory is that it can only work if there are more than three dimensions in the universe — a number which could be as many as eleven. These non-observable miniscule dimensions surround the strings and influence their vibrations . Understanding these strings can help answer why particles act the way they do.
Testing string theory directly is impossible with modern technology because the strings are so small; in addition, the theory hasn’t been completely worked out yet. But we can potentially test clues to string theory that may strengthen the theory . Scientists who work at CERN, an organization for nuclear research, use the Large Hadron Collider, a massive particle accelerator laced with magnets, to ram together particles and test something called supersymmetry - a theory that unifies the building blocks of the universe with the force carriers , particles that contain bundles of energy and create forces in between two objects by traveling back and forth between the affected particles. An example of this is the photon, a massless fundamental particle that travels at the speed of light in between particles to induce electromagnetic forces. Unfortunately, no evidence has been found for supersymmetry through the LHC .
Roger Penrose, a world renowned physicist and recent Nobel laureate, argues that string theory is extremely attractive because of its simplicity and ambition, but nonetheless it remains a fantasy . Scientists have now worked on it for a few decades with no empirical evidence proving its existence. Penrose has famously gone against the tide of mainstream modern physics with his skepticism of the theory. With billions of dollars spent on the endeavors of string theorists, Penrose raises the realist’s question: is all the money, time, and effort worth it?
For years, work has been done using the LHC and until now they have made only one notable discovery: the Higgs Boson. Although many scientists working at CERN do research on proving string theory, they have yet to find any true evidence . Penrose argues that they are grasping at straws.
Searching for a unified theory is a rare gem that physicists will continue to seek until it is proven — one way or another. Finding success when it comes to string theory comes with a reward for a scientist far greater than anyone can imagine. It would tell us that the secrets of our universe are able to be discovered in one simple string of vibrating energy. However, as the years progress and attempts fall short, physicists may have to accept that Einstein’s theory was missing a piece that may not be related at all.
Roger Penrose is not alone in his skepticism of string theory. Many physicists have expressed how they are unimpressed with the bold aspirations of these projects. As long as there is the prospect of achieving such an ideal grasp of our universe, though, I believe physicists all over the world will still try to prove string theory by coming at the problem from every angle imaginable .
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