On 21 October 2020, Professor Neil Lambert delivered a BMUCO talk tracing the conceptual thread from the Higgs mechanism—which explains how particles acquire mass—to superstring theory's vision of fundamental physics.
The Higgs Discovery
"The Higgs boson represents just one manifestation of deeper symmetries that may unify all forces and particles."
The lecture illuminated how the Higgs boson, discovered at CERN in 2012, represents just one manifestation of deeper symmetries that may unify all forces and particles.
How Particles Get Mass
The Higgs mechanism solves a profound puzzle: why do some particles have mass while others (like photons) don't?
The answer involves a field—the Higgs field—that permeates all of space. Particles interact with this field as they move through it:
- Strong interaction: Heavy particles like the top quark
- Weak interaction: Light particles like electrons
- No interaction: Massless particles like photons
When the Higgs field "freezes" into a particular configuration (much like water freezing into ice), particles that interact with it acquire mass through this interaction.
The String Theory Connection
Prof. Lambert explained how string theory proposes that the universe's fundamental constituents are not point-like particles but vibrating strings, with different vibration modes corresponding to different particles.
Why Strings?
String theory offers several compelling features:
- Natural gravity: The theory automatically includes gravitons—particles that carry gravitational force
- Unification: All particles emerge from a single fundamental object (strings)
- Quantum consistency: The mathematics resolves contradictions between quantum mechanics and gravity
- Rich structure: Multiple dimensions and sophisticated geometry emerge naturally
From Points to Strings
In conventional particle physics, particles are mathematical points with no internal structure. String theory replaces this with one-dimensional strings—tiny loops or segments vibrating in space.
Just as a violin string produces different musical notes depending on how it vibrates, fundamental strings produce different particles—electrons, quarks, photons, gravitons—through their various vibration patterns.
The Higgs boson would be one such vibration mode, but string theory predicts many more particles yet to be discovered, along with extra spatial dimensions beyond the three we experience.
Unifying Everything
The ultimate goal is a "theory of everything"—a single mathematical framework that describes all forces and particles. String theory offers a candidate for this framework, though experimental confirmation remains an ongoing challenge.
Watch the full lecture:
youtube.com/watch?v=tNRcFXkTPOA