Related Experiment Video
Updated: Aug 14, 2026

07:46
Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
A Clifford algebra approach to bosonic strings with fermionic boundaries
Andrew Hamilton1, Tyler McMaken2
1University of Colorado Boulder , Boulder, CO, USA.
Summary
Bosonic string theory aligns with the Standard Model by incorporating fermions and a Higgs-like tachyon, challenging the need for supersymmetry. This geometric algebra approach offers a new perspective on fundamental forces.
Area of Science:
- Theoretical Physics
- High Energy Physics
- Geometric Algebra
Background:
- The Brauer-Weyl theorem establishes an isomorphism between spinor tensor product algebras and Clifford algebras.
- The Standard Model's fermion-boson relationships align with the Brauer-Weyl theorem, but not with supersymmetry.
- Supersymmetry is often considered essential for string theory due to perceived issues with non-supersymmetric bosonic string theory.
Purpose of the Study:
- To rebut common objections to non-supersymmetric bosonic string theory.
- To demonstrate how bosonic string theory can accommodate fermions and a Higgs-like field.
- To propose bosonic string theory as a unified framework for fundamental forces.
Main Methods:
- Re-examination of the Brauer-Weyl theorem's implications for particle physics.
- Analysis of fermionic states within the D-brane boundary of open strings.
- Characterization of the open-string tachyon as a Higgs field.
Main Results:
- Bosonic string theory admits fermions on D-brane boundaries.
- The open-string tachyon exhibits properties consistent with the Higgs field.
- The 1970s formulation of bosonic string theory, when viewed as a theory of all forces, aligns with the Standard Model.
Conclusions:
- Supersymmetry is not a necessary requirement for string theory.
- Bosonic string theory provides a viable framework for unifying fundamental forces and describing the Standard Model.
- Geometric algebra offers powerful tools for understanding modern physics.
Related Concept Videos
Boundary Conditions for Current Density
Current density becomes discontinuous across an interface of materials with different electrical conductivities. The normal component of the current density is continuous across the boundary.
Electrostatic Boundary Conditions
Consider an external electric field propagating through a homogeneous medium. When the electric field crosses the surface boundary of the medium, it undergoes a discontinuity. The electric field can be resolved into normal and tangential components. The amount by which the field changes at any boundary is given by the difference between the field components above and below the surface boundary.
The surface integral of an electric field is given by Gauss's law in integral form and is related to...
The surface integral of an electric field is given by Gauss's law in integral form and is related to...
Boundary Conditions: Lossless Lines
Consider a single-phase, two-wire, lossless transmission line terminated by an impedance at the receiving end and a source with Thevenin voltage and impedance at the sending end. The line, with length, has a surge impedance and wave velocity determined by the line's inductance and capacitance.
At the receiving end, the boundary condition states that the voltage equals the product of the receiving-end impedance and current. This relationship is expressed as a function of the incident and...
At the receiving end, the boundary condition states that the voltage equals the product of the receiving-end impedance and current. This relationship is expressed as a function of the incident and...
Electrostatic Boundary Conditions in Dielectrics
When an electric field passes from one homogeneous medium to another, crossing the boundary between the two mediums imparts a discontinuity in the electric field. This results in electrostatic boundary conditions that depend on the type of mediums the field propagates through.
Consider a case where both the mediums across a boundary are two different dielectric materials. Recall that the electric field and electric displacement are proportional and related through the material's permittivity.
Consider a case where both the mediums across a boundary are two different dielectric materials. Recall that the electric field and electric displacement are proportional and related through the material's permittivity.
MO Theory and Covalent Bonding
The molecular orbital theory describes the distribution of electrons in molecules in a manner similar to the distribution of electrons in atomic orbitals. The region of space in which a valence electron in a molecule is likely to be found is called a molecular orbital. Mathematically, the linear combination of atomic orbitals (LCAO) generates molecular orbitals. Combinations of in-phase atomic orbital wave functions result in regions with a high probability of electron density, while...
Couples: Scalar and Vector Formulation
One might wonder how the captain of a large ship can navigate through the ocean with just a turn of the steering wheel. The answer lies in the concept of two parallel forces that are equal in magnitude and opposite sense, creating a couple moment.
A couple moment is a rotational force that tends to rotate the steering wheel. The wheel's rotation can either be in a clockwise or anticlockwise direction. The right-hand rule is a helpful method for determining the direction of a couple moment. To...
A couple moment is a rotational force that tends to rotate the steering wheel. The wheel's rotation can either be in a clockwise or anticlockwise direction. The right-hand rule is a helpful method for determining the direction of a couple moment. To...

