By AI, a compilation of sources
Supersymmetry (SUSY) is a theoretical framework in physics that proposes a fundamental symmetry between bosons and fermions, suggesting that each known particle has a heavier “superpartner” with different spin. This symmetry aims to address several shortcomings of the Standard Model of particle physics, potentially explaining the weakness of gravity, the existence of dark matter, and the Higgs boson’s mass.
Here’s a more detailed explanation:
Core Idea:
- Symmetry between Bosons and Fermions: Supersymmetry posits that for every known boson (force-carrying particle), there exists a corresponding fermion (matter particle) with similar properties, and vice versa.
- Superpartners: These hypothetical particles, called superpartners, have different spin values than their Standard Model counterparts. For example, the superpartner of an electron (a fermion) would be a scalar particle called a selectron (a boson), and the superpartner of a photon (a boson) would be a photino (a fermion).
Motivations:
- Hierarchy Problem: Supersymmetry could explain why the Higgs boson’s mass is so much lighter than predicted by the Standard Model, by having superpartners cancel out contributions from Standard Model particles.
- Dark Matter: The lightest superpartner, often a neutralino, could be a candidate for dark matter, an unknown form of matter that makes up a significant portion of the universe’s mass.
- Unification of Forces: Supersymmetry could potentially help unify gravity with the other fundamental forces, as it predicts that gravity’s force-carrying particle, the graviton, would have a superpartner.
Status and Experimental Evidence:
- No Direct Detection: Despite extensive searches at particle accelerators like the Large Hadron Collider (LHC), no superpartners have been directly detected, leading to some skepticism about the theory.
- Indirect Evidence: While direct detection is lacking, some researchers believe there might be indirect evidence for supersymmetry, such as the existence of dark matter. Further research is ongoing.
- Challenges and Alternative Theories: The lack of direct evidence has led to the development of other theoretical frameworks that attempt to address the shortcomings of the Standard Model, such as string theory.
In essence, supersymmetry is a compelling theoretical framework that offers potential solutions to some of the biggest mysteries in particle physics, but it remains unproven and faces challenges in terms of experimental verification.
S. James Gates, Jr: https://81018.com/2019/04/09/gates/
https://81018.com/reformatting/#Susy
Much more work to come…
Bruno Zumino, Julius Wess, Peter van Nieuwenhuizen. Sergio Ferrara
In 1971, he and Julius Wess wrote an important paper on anomalies—quantum effects that spoil the symmetries of classical field theories. It introduced what came to be known as “Wess-Zumino terms,” and had far-reaching ramifications both in physics and mathematics. Later, in 1974, Bruno and Julius were studying string theory—according to which the point particles of quantum field theory are replaced by tiny two-dimensional objects, or “strings,” to describe the strong force. Originally formulated as a theory of bosons—particles with integer spin, or intrinsic angular momentum, string theory was generalized by Pierre Ramond, and by André Neveu and John Schwarz, to include fermions—half-integer spin particles. After these three physicists introduced a symmetry relating bosons and fermions in the two-dimensional system that described the coordinate along the string as a function of time, Julius and Bruno asked themselves if a similar symmetry—now known as supersymmetry—could be realized in our four-dimensional world.
Also, in Moscow Yuri Golfand and Evgeny Likhtman, then in Kharkov by Dmitrij Volkov, Vladimir Akulov, and Vyacheslav Soroka…
“N = 8 supergravity.”
Mary K. Gaillard (wife of Bruno Zumino) Berkeley, CERN, CRNS, theoretical physicist. “I am interested in pushing particle theory beyond the well-established Standard Model. My work in recent years has focused on the symmetry breaking mechanism by which particles acquire masses, and more specifically on supersymmetry and supergravity. Supersymmetry provides a possible mechanism for understanding the large hierarchy in scale between the masses of particles studied with accelerators and the “natural” scale of physics which is the Planck mass.” https://physics.berkeley.edu/people/faculty/mary-k-gaillard. Died: May 2025