1. Einstein’s Brane

2. 1632 1642 1687 1904 1905 1915 1907 1616

3. NEWTON’S GRAVITATIONAL CONSTANT SPEED OF LIGHT EINSTEIN’S COSMOLOGICAL CONSTANT EINSTEIN’S COSMOLOGICAL CONSTANT

5. Weyl, 1918 Kaluza, 1921 Klein, 1926 Einstein 1925  Some good ideas but many ingredients are missing! Some good ideas but many ingredients are missing! Gauge Invariance

6. Three ``families’’ of elementary particles! ++ + = Quantum of Electromagnetic wave Quantum of Electromagnetic wave

7. TWO GIFTS FROM the SEVENTIES Unifies matter and forces    Not (yet) seen!

8. Small amplitude wave: Ideal Strings v 2 = T/ρ v  (kg/m) (Newtons) (Energy density)

9. Kinds of string Energy density

10. Lowest oscillation state is the graviton But, need supersymmetry AND 9 space dimensions There are just five of these

11. Open strings end on branes: (extended in 2 space dimensions)

12. p=1. p=2. p=3. p=4....... possible with extra space dimensions! Space filling!

13. Kinds of Branes T T T T T Surface Tension T Mass density ρ String theory branes saturate the bound: T= ρc 2 String theory branes saturate the bound: T= ρc 2 e.g. a drum T << ρc 2 e.g. a drum T << ρc 2 T ≤ ρc 2

14. Membrane in 10 space dimensions String in 9 space dimensions Kaluza-Klein at work Now, even strings are really branes

15. Brane Democracy (but some are more equal than others) That’s because they are all made from the same T= ρc 2 ``stuff’’ That’s because they are all made from the same T= ρc 2 ``stuff’’ String 3-brane (for example)

16. electron Higgs boson positron.. Quark Particles are quanta of fluctuations of branes

17. BRANES vs BULK Interact only via gravity Branes

18. Equivalent to filling space with a T= ρc 2 tensile materiala Vos calculs sont corrects mais votre physique est abominable

19. Why is Gravity different? Gravity resists unification with other forces of nature. As formulated by Einstein, it appears incompatible with Quantum Mechanics M-theory explains why: Gravity governs the dynamics of the BULK Other forces act only on BRANES

20. Modern idea: it emerges holographically from quantum fields on branes Holograph image fuzzy image

21. Pointillism vs Ondulism Seurat Monet