Selected developments in Physics during the last few centuries

1. Selected developments in Physics during the last few centuries E. Matsinos (mato@zhaw.ch)

2. On how progress is made Is this the end of Physics?

3. On how progress is made Complacency Is this the end of Physics?

4. On how progress is made Is this the end of Physics?

5. On how progress is made Dissension Is this the end of Physics?

6. On how progress is made Maximisation of activity (mainly by theorists) Is this the end of Physics?

7. On how progress is made Creativity phase Nothing seems to make sense Is this the end of Physics?

8. On how progress is made Complacency Is this the end of Physics?

9. The scientific method “Principles and procedures for the systematic pursuit of knowledge involving: • the recognition and formulation of a problem, • the collection of data through observation and experiment, and • the formulation and testing of hypotheses” [Webster's dictionary] Is this the end of Physics?

10. From Mythology to Geometry Eratosthenes of Cyrene (276 BC – ca. 195 BC) First measurement of the Earth radius First measurement of the Moon radius (eclipse) First measurement of the Earth-Moon distance Is this the end of Physics?

11. From Mythology to Geometry Aristarchus of Samos (310 BC – ca. 230 BC) First measurement of the Earth-Sun distance (a factor of 20 off!) First measurement of the Sun radius Is this the end of Physics?

12. From Mythology to Geometry Aristarchus of Samos (310 BC – ca. 230 BC) Heliocentric Cosmology • Why was Aristarchus’ Heliocentric Cosmology not accepted? • If the Earth moved, there should be constant ‘wind’ and the ground should disappear under our feet • If the Sun were the centre of the universe, then all objects (on the Earth) should fall onto (move toward) it • Stellar parallax Friedrich Wilhelm Bessel, 1838; 313.6 mas (0.00008710) Today’s value: 287.18 mas (→ 11.36 ly) Is this the end of Physics?

13. From Mythology to Geometry Claudius Ptolemy (ca. 90 – 168) • Almagest: the only surviving comprehensive ancient treatise on astronomy • Tables to compute future (or past) positions of the Sun, Moon, and planets; also the rising and the setting of the stars Geocentric Cosmology Is this the end of Physics?

14. Medieval Cosmology Wycliffe Translation Psalm 93:1 for he [the Lord] made steadfast the world; that shall not be moved Psalm 96:10 and he [the Lord] hath amended the world, that shall not be moved Psalm 104:5 which hast founded the earth on his stableness; it shall not be bowed into the world of world 1 Chronicles 10:3 for he [the Lord] hath founded the world unmoveable Ecclesiastes 1:5 the sun riseth, and goeth down, and turneth again to his place; and there it riseth again Is this the end of Physics?

15. Starting the scientific revolution Nicolaus Copernicus (1473 – 1543) • Heliocentric Cosmology removed the Earth from its privileged status of being the ‘centre of the universe’ De revolutionibus orbium coelestium, 1543 Is this the end of Physics?

16. Starting the scientific revolution From Copernicus' Commentariolus (1514): • There is no one centre of all the celestial circles or spheres. • The centre of the Earth is not the centre of the universe, but only of gravity and of the lunar sphere. • All the spheres revolve about the Sun... • ... the distance from the Earth to the Sun is imperceptible in comparison with the height of the firmament. • Whatever motion appears in the firmament arises not from any motion of the firmament, but from the Earth's motion. The Earth ... performs a complete rotation on its fixed poles in a daily motion, while the firmament and highest heaven abide unchanged. • What appear to us as motions of the Sun arise not from its motion but from the motion of the Earth ... We revolve about the Sun like any other planet. • The apparent retrograde and direct motion of the planets arises not from their motion, but from the Earth's. The motion of the Earth alone, therefore, suffices to explain so many apparent inequalities in the heavens. Is this the end of Physics?

17. Observations Haec immatura a me iam frustra leguntur oy (These are at present too young to be read) Cynthiae figuras aemulatur Mater Amorum (Cynthia's figures are imitated by the Mother of Love) Is this the end of Physics?

18. History Isaac Newton (1642 – 1727) • Foundation of Classical Mechanics Is this the end of Physics?

19. History • The nature of light • Newton (particle aspect) • Huygens (wave aspect) • Rømer (c is finite, Io’s eclipses, 1676) • Young’s experiment (1803) • The classification of the elements • Lavoisier • Gay-Lussac • Mendeleyev • Electromagnetism • Ørsted • Faraday Is this the end of Physics?

20. History Differential form of Maxwell’s ‘microscopic’ equations Gauss’ law Gauss’ law for magnetism Faraday’s law Ampère’s law Is this the end of Physics?

21. History Classical Physics • Gravitation (Newton) • Electromagnetism (Maxwell) Galilean transformation • Open questions/problems • Invariance of laws of Physics • Relativity principle • Introduction of aether • Structure of matter Is this the end of Physics?

22. History The Michelson–Morley experiment (1887) Aimed at detecting the relative motion of matter relative to the luminiferous aether (aether wind) Negative result Is this the end of Physics?

23. History Albert Einstein (1879 – 1955) Special Theory of Relativity (1905) General Theory of Relativity (1915) • Strong gravitational fields distort the space-time • It did not take long for GR to be tested and verified • precession of Mercury’s perihelion, • deflection of light of remote galaxies, … Is this the end of Physics?

24. History • General Relativity generalises Special Relativity and Newton’s law of universal gravitation, providing a unified description of gravity as a geometric property of space-time Is this the end of Physics?

25. History Precession of the perihelion of Mercury’s orbit Recognised in 1859 as a problem in celestial mechanics by Urbain Le Verrier (re-analysis of the transits of Mercury over the Sun’s disk from 1697 to 1848); Le Verrier estimated an anomaly of 38 arcsec/century Is this the end of Physics?

26. An ‘extreme case’ of precession PSR B1913+16 (Hulse–Taylor binary pulsar) • Binary-star system: two neutron stars (M~1.4M☼) orbiting each other → precession of the periastron: 4.20 yr-1 • T=7.751939106 hr • e=0.617131 • a=1,950,100 km • Rate of decrease of orbital period: 76.5 ms/yr • Rate of decrease of semi-major axis: 3.5 m/yr • Calculated lifetime: 300 Myr Is this the end of Physics?

27. History Gravitational deflection of light arcsec Is this the end of Physics?

28. History Gravitational deflection of light Is this the end of Physics?

29. History The ray-frenzy era Röntgen von Laue Bequerel Curie’s Rutherford First Solvay Conference, 1911 Is this the end of Physics?

30. History Plum-pudding model ‘… as if you fired a 15-inch shell at a piece of tissue paper and it came back and hit you’ First ‘realistic’ model of the atom Is this the end of Physics?

31. History Fifth Solvay Conference, 1927 Quantum mechanics Planck Rutherford Bohr Pauli Heisenberg Schrödinger de Broglie Born Dirac Is this the end of Physics?

32. Fundamental forces and elementary particles (1st half of 20th century) Electromagnetism Quantum Theory Gravitation Electron (Thomson, 1897) Proton (Rutherford, 1919) Neutron (Chatwick, 1932) - Rutherford Antielectron (Anderson, 1932) - Dirac Muon (Anderson, 1936) Pion (Powell, 1947) - Yukawa One problem solved (electrons in stable orbits), another remained (stability of the nucleus) Is this the end of Physics?

33. Fundamental forces and elementary particles (2nd half of 20th century) Birth of Quantum Electrodynamics (QED) Feynman, Schwinger, and Tomonaga (Maxwell’s equations + Quantum Theory + Special Theory of Relativity) Is this the end of Physics?

34. Fundamental forces and elementary particles (2nd half of 20th century) Cyclotron (Lawrence) Cockcroft-Walton Synchrotron (McMillan) 1952: BNL, proton synchrotron, 3 GeV; Cosmotron Is this the end of Physics?

35. Fundamental forces and elementary particles (2nd half of 20th century) 1954: Berkeley, 6 GeV; Bevatron 1957: Dubna, 10 GeV; Synchrophasotron New particles were discovered with these accelerators Further discoveries Electron neutrino (Cowen and Reines, 1953) - Pauli Muon neutrino (Steinberger, Ledermann, and Schwartz, 1962) 1957: CERN, 28 GeV; PS ring Is this the end of Physics?

36. Fundamental forces and elementary particles (2nd half of 20th century) Is this the end of Physics?

37. Fundamental forces and elementary particles (2nd half of 20th century) Gell-Mann and Ne’eman arranged the existing hadrons in geometrical patterns Gell-Mann predicted the existence of a new particle in 1962, discovered one year later Friedman, Kendall, and Taylor showed that the proton has structure Gell-Mann and Zweig introduced the quarks as elementary blocks of matter Introduction of ‘colour’ Baryons consist of three quarks Mesons consist of a quark-antiquark pair Quantum Chromodynamics (QCD) is born Fritzsch, Gell-Mann, and Leutwyler (early 1970s) The six quarks (u, d, c, s, t, and b) are the building blocks of the hadrons and they interact by exchanging gluons Is this the end of Physics?

38. Fundamental forces and elementary particles (2nd half of 20th century) GR QED Weak QCD Do these states really exist? 10-38 1/137 10-13 1 Is this the end of Physics?

39. Fundamental forces and elementary particles (2nd half of 20th century) GR QED Weak QCD Electroweak Glashow, Weinberg, and Salam (Higgs, t’ Hooft) Standard Model ~ 125 First evidence for gluons (three-jet events, PLUTO, 1978) First evidence for W+, W-, Z0 (UA1 and UA2, 1983) The Higgs boson was tentatively confirmed to exist on 14 March 2013 (ATLAS and CMS, 4 July 2012) Is this the end of Physics?

40. Unification: problems • There is no real unification between the Electroweak interaction and QCD; they simply co-exist within the Standard Model • There is little logics in the grouping of the elementary blocks of matter • Fermion-boson asymmetry • The Standard Model contains 24 parameters which cannot be obtained from ‘principles’ • GRAVITY AND QUANTUM THEORY ARE CONCEPTUALLY INCOMPATIBLE Is this the end of Physics?

41. Unification: why bother? • Order and simplicity • At the early times of the Universe, gravitation was equally important as the other forces • Quantum fluctuations in the ‘primeval soup’ led to the creation of stars and galaxies Is this the end of Physics?

42. Unification String Theory (1980s) All the particles (and all forms of energy) in the Universe may be identified as one-dimensional, tiny 'strings' Our Universe is functioning in ten (or eleven) dimensions! Five string theories have emerged and seem to be self-consistent! M-theory (Witten, 1994) ‘The true sign of intelligence is not knowledge, but imagination’ [Albert Einstein] Is this the end of Physics?

43. Future 'The most important fundamental laws and facts of physical science have all been discovered, and these are now so firmly established that the possibility of their ever being supplemented in consequence of new discoveries is exceedingly remote... Our future discoveries must be looked for in the sixth place of decimals.' Albert Michelson, University of Chicago, 1894 Is this the end of Physics?

44. Thank you! E. Matsinos (mato@zhaw.ch) Is this the end of Physics?