1. Spontaneous Symmetry Breaking and Analogies to the Higgs-Mechanism
Superconductivity and Ferromagnetism
Spontaneous Symmetry Breaking and Analogies to the Higgs-Mechanism
Robin Zech

2. Outline Review: Spontaneous Symmetry Breaking Ferromagnetism
Superconductivity
The BEH-Field as a Cosmic Superconductor
Robin Zech

3. Spontaneous Symmetry Breaking
breaking parameter
(e.g. temperature)
Robin Zech

4. Spontaneous Symmetry Breaking
Symmetric physical laws but nonzero ground state (expectation value)
“Breaking” with respect to a certain symmetry group
Excitations around minimum
 (gauge) particles
Robin Zech

5. Spontaneous Symmetry Breaking
Higgs-Mechanism
Ferromagnetism
Superconductivity
Superfluidity
Origin of hadron masses
Robin Zech

6. Ferromagnetism
Electrons have an angular momentum (spin)  microscopic magnetic field
Over Curie temperature: no macroscopic magnetization can build up
Lowering temperature  spontaneous aligning of microscopic dipoles creates macroscopic dipole field
 broken rotational invariance
Robin Zech

7. Ferromagnetism http://www.tulane.edu/~sanelson/images/curiet.gif
Robin Zech

8. Superconductivity
Electrical resistance exactly zero under critical temperature
BCS theory (1972)
Cooper pairs of electrons, which all have the same phase
 Bose-Einstein-Condensate
Breaking of U(1) phase symmetry (before: changing the phase via photon exchange of two electrons)
Robin Zech

9. Superconductivity Meissner effect: Virtual photon mass
Superconductor is ideal diamagnetic  no electromagnetic fields
Characteristic penetration depth (≈10…100 nm)
Virtual photon mass
Second length scale: coherence length
Robin Zech

10. Superconductivity External magnetic field …
Type I: breakdown of superconductivity at critical value
Type II: formation of magnetic vortices
Robin Zech

11. The BEH-Field as a Cosmic Superconductor
Superconductivity
BEH Field
‘Sea’ of electric charges (Bose-Einstein-Condensate)
‘Sea’ of weak charges
Breaking of U(1) phase symmetry
Breaking of SU(2) symmetry
Condensation at ≈ 1…200K
≈ 1015 K
Cancellation of electromagnetic fields or photons
Cancellation of weak force or W/Z-Bosons
Penetration depth (≈100 nm)
Range of weak force (10-18 m)
Coherence Length (≈100 nm)
Mass of the Higgs Boson
Robin Zech

12. The BEH-Field as a Cosmic Superconductor
 Superconductivity for electromagnetic charge is analogue to Higgs mechanism for weak charge!
BEH field 10 billion times more effective than superconductivity!
Robin Zech

13. The BEH-Field as a Cosmic Superconductor
Question: BEH-Field = elementary field?
Superconductivity: ‘bosons made of fermions’
 technicolor theory
Robin Zech

14. Sources
Coughlan, Dodd and Gripaios, 2006, “The Ideas of particle Physics, An Introduction for Scientists, Third Edition”
Thomson, 2013, “Modern Particle Physics”
Dixon, 1996,
Kobel, 2013,
Robin Zech