Tag Archive | String Theory

Introduction to Particle Physics Part 4: Beyond the Standard Model

We know the Standard Model can’t be everything, as it only explains 3 of the fundamental forces of nature (the missing one being gravity). When we look out into the universe, we see that galaxies are spinning at the wrong speeds, that things that should be unstable are stable and that galactic clusters are bending light more than they should. This is strong evidence for a new form of matter that doesn’t interact with light – so called dark matter.

And if that isn’t crazy enough, the universe seems to be getting bigger at a faster rate (imagine throwing a ball in the air and it shooting upwards with ever increasing speed, totally counter intuitive). This is caused by something we call dark energy, which is a mysterious substance now believed to make up the vast majority of the energy content of our universe. As to what it actually is, we still don’t know.

Galaxy rotation curves - evidence for dark matter

Galaxy rotation curves – evidence for dark matter

So after all that hard work, it seems that the Standard Model only explains about 5% of the universe, oh well, it was nice trying. BUT WAIT! If there’s one thing Physicists are good at, it’s creating seemingly crazy ideas that just might turn out to be right…

One potential explanation of dark matter is that there is a whole new collection of super-heavy particles that we haven’t seen yet – the so called theory of supersymmetry. If we find evidence of such particles in particle colliders, it could even help us pave the way towards understanding if string theory is correct or not!

A Calabi-Yau manifold – welcome to the strange world of string theory

A Calabi-Yau manifold – welcome to the strange world of string theory

A recurring theme throughout our story was how things that once seemed disconnected are actually part of a deeper underlying truth, so it’s natural to wonder if one day we could unify all the fundamental forces into a single explanation – a theory of everything. The Large Hadron Collider may finally be the window to open our eyes to such new and exciting possibilities.

One thing is clear though: we stand on the precipice of perhaps the greatest change in our understanding of the universe – and the Higgs boson might just be the key to unlocking it all.

(Next time: What is the Higgs boson?)