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From Physics Graduate Student in the '70s to Observing Supernovae Today

A Festschrift and Conference on THE GOLDEN AGE OF PARTICLE PHYSICS AND ITS LEGACY Boston University In honour of Lawrence Sulak. From Physics Graduate Student in the '70s to Observing Supernovae Today. Charling Tao Centre de Physique des Particules de Marseille IN2P3/CNRS and U. Méditerranée

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From Physics Graduate Student in the '70s to Observing Supernovae Today

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  1. A Festschrift and Conference onTHE GOLDEN AGE OF PARTICLE PHYSICS AND ITS LEGACY Boston UniversityIn honour of Lawrence Sulak From Physics Graduate Student in the '70s to Observing Supernovae Today Charling Tao Centre de Physique des Particules de Marseille IN2P3/CNRS and U. Méditerranée ITA NAOC Beijing

  2. :-* OK! The title of your talk is: From Physics Graduate Student in the '70s to Observing Supernovae Today Foreword We would particularly be interested in hearing your thoughts on ``The life of a physics graduate student in the '70's". Aie !!Yaie!!! I am not a sociologist!!!!   wish I had Tom Wolfe’ s talent for a « I am Charlotte Simmons » speech! Perhaps I could talk about my present work on SN and Dark Energy. Would be easier for me…

  3. My graduate years: 1975-1979 Harvard U. My Thesis (R. Wilson) : The Structure and Formation of Hadrons: An Experiment with a Muon Beam of 219 GeV on a Hydrogen Target. Test of QCD:logarithmic breaking of scale invariance Frontiers of physics at the time

  4. My Harvard graduate school environment :-) Adviser:Richard Wilson, (+ A.L. Sessoms + T. Loomis) Teachers: Sidney Coleman : QFT (John Lo Secco) Shelly Glashow: Group Theory Alvaro de Rujula: Weak Interactions Steven Weinberg: General Relativity and Cosmology Carlo Rubbia: Particle Physics Howard Georgi,… Lots of other people around at the time: N. Ramsey, P. Martin, F.Pipkin, K. Strauch, Ed Witten, D. Politzer, G. t’Hooft, P. MacIntyre, W. Skocpol, Tinkham, …. Students at the time present today ; Witold Kozanecki, Jim Strait, Michael Levi, Bruce Cortez, Ian Affleck, Dave Hannah, Wesley Smith, …

  5. Harvard PhD 1979, 10/20 in particle physics • AFFLECK, IAN KEITH,. Some Results on Vacuum Decay. (Coleman) • ALVAREZ, ORLANDO, Conformal Invariance in Quantum Field Theory. (Weinberg) • DAVIS, SAMUEL, Predictions and Limitations of Perturbative QCD. (Georgi) • DE LUCCIA, FRANK JOSEPH, The Fate of the False Vacuum: Induced Decay and Gravitational Effects on Spontaneous Decay. (Coleman) • RICH, JAMES ARNOLD, Trimuon Production by High Energy Neutrinos. (Rubbia) • ROCEK, MARTIN,. Aspects of Spontaneous Symmetry Breakdown of Supersymmetry. (Wu) • SHEIMAN, JOHATHAN LEWIS, Topics in the Theory of Leptoproduction. (Georgi) • SMOLIN, LEE, Studies in Quantum Gravity. (Coleman) • SOBELMAN, GERALD EDWARD, Asymptotic Estimates and Borel Resummation for a Doubly Anharmonic Oscillator. (Coleman) • TAO, CHARLING SUN,The Structure and Formation of Hadrons: An Experiment with a Muon Beam of 219 GeV on a Hydrogen Target. (Wilson)

  6. :-* 1975 class: 32 graduate students 1 female and only 1 other 6 years before! Year after : 2 female graduate students Since then, at least 1 graduating /year Not great! But not 0 Thank you Larry (and Beth) for the conscious effort to bring more women in science

  7. What did I learn from Graduate school in the 70’s? • The Feynman Problem Solving Algorithm:1) Write down the problem. 2) Think very hard. 3) Write down the solution. :-)

  8. What did I learn from Graduate school in the 70’s? - A lot of physics, and detector building, of course, - need to work hard But more important is the Scientific Method When faced with any problem: Don’t be afraid,ask questions Example of Larry : an ever young, enthusiastic and curious mind And do not forget to be socially conscious and active

  9. What is Physics? Physics is an art, the art of unveiling the invisible

  10. What is Physics? Physics is a language, a « universal » human language that translates the « real » world into something « understandable »

  11. What did I learn from Graduate school in the 70’s? There are many ways to do physics and understand Nature Reductionnist / Emergent Theoretical / experimental/ phenomenology Different fields Choose one path in graduate school and learn the techniques

  12. Why did I do a thesis on tests of QCD in Deep Inelastic Muon Scattering in 1975 ? And why SNIa search today? The Larry Sulak/Harvard Spirit Frontiers of Physics

  13. (

  14. g strong g electromagnetic Z0 , W+ ,W- weak gravitation ‘G’ Vector bosons of interactions 1970’s frontiers of physics? ne nm nt leptons m e t c u t ‘H0’ quarks s d b 3 fermion families Fundamental particles interactions

  15. g strong g electromagnetic Z0 , W+ ,W- weak gravitation ‘G’ Vector bosons of interactions 1970’s frontiers of physics? ne nm nt leptons m e Completing our knowledge of Fundamental Particle constituents of matter and Fundamental interactions t c u t ‘H0’ quarks s d b 3 fermion families Fundamental particles interactions

  16. The Golden Age of particle physics In 1950-s : advent of particle accelerators beams of electrons or protons with high kinetic energy. the 4.5-inch model cyclotron built by Lawrence and Livingston. Oct. 20, 1955: discovery of the antiproton

  17. Can plan the experiments and repeat them! High energy physics  Particle physics second name •  many new particles • new classification: leptons, mesons, baryons « the eightfold way » Gell-man & Neeman Nobel Prize in Physics 1969 • Leptons and quarks

  18. Sheldon Glashow Steven Weinberg Abdus Salam 1970’s frontiers of physics? Towards the Standard Model of the Fundamental interactions SU(3) x SU(2) x U(1) 1973 • Asymptotic freedom:Quantum Chromodynamics (QCD) - Unification of weak and electromagnetic interactions (discovery of Neutral currents)

  19. Nobel for v beams and vm 1970’s frontiers of physics? Completing the particle constituent table ~1975 - J/Psi discovered (S.Ting et al., Richter et al.) evidence for charm, postulated in 1973 (GIM) - tau lepton (M. Perl et al.): Indication for a third family Completing the third family 1977: beauty (Lederman et al.) 1995: top quark discovery

  20. 1980’s: Triumph of the Standard Model • Unification electromagnetism and weak interaction Prediction of W, Z observed at CERN UA1/2 experiments (C. Rubbia et al….) First W First Z

  21. Where was ? IMB Proton decay + Neutrino Osc. + SN1987A

  22. n First hint of neutrino masses: Next frontiers ? Beyond the SM of particle physics First hint with neutrino masses ? L. Wolfenstein

  23. Solar neutrino problem A pioneering experiment… 1970 R. Davis 600 tons of C2Cl4 ne+ 37Cl 37Ar + e- Homestake

  24. Probing the Universe with neutrinos SuperKamiokande neutrino image of the Sun Pioneering Involvement in neutrino telescopes DUMAND started in 1976 IMB/ SuperK in 1978/1979

  25. The ANTARES underwater detector in the Mediterranean sea 12 lines (900 PMTs) 25 storeys / line 3 PMTs/storey Horizontal layout P.Coyle 2500 m 40 km to shore storey 14.5 m 350 m 100 m Junction box 70 m Readout cables

  26. )

  27. Next frontiers • Cosmology • Dark Matter • Dark Energy Quantum theory • SUSY • Superstrings • Quantum Gravity Is the cosmological constant, constant? What is its relationship with quantum vacuum fluctuations? New particles? Extra dimensions? Negative energies? Space topologies? Violation of Lorentz invariance?  Accelerator physics is fundamental but new physics hints could be coming from « astro » and « cosmo » data (Back to Cosmic Ray physics!)

  28. A mysterious Universe 1/3 Dark Matter 2/3 Dark Energy WMAP Position 1st peak WT=1.02 +/- 0.02 Flat universe Definition:W=r/rc (rc=10-29 g/cm3) Ratio (2/1) peaks WB =0.046 +/- 0.006 Ordinary Matter: 4% • CMB, + SN, clusters, galaxies redshift surveys, Weak Lensing, … • Concordant LCDM model with Cold Dark MatterandCosmological constant

  29. Why SNIa search today? Mystery of the Dark Universe ! (Michael Levi) • What expertise do we bring to the field? Handling of large sample of data • Control of systematics: from a 2s measurement to a credible result • SNLS is one step • Nearby supernovae program VERY important! • SNAP/JDEM 1% measurement Today’s Frontiers of physics

  30. Different standardisation methods Before:mB After, eg, stretch correction: mBcor = mB – a (s-1) Different standardisation methods :stretch (SCP), MLC2k2 (HiZ), Dm15, ...

  31. SN Ia in 2004: A selection by Riess et al,astro-ph 0402512 16 new SN Ia with HST(GOOD ACS Treasury program) 6 / 7 existing with z >1.25 + Compilation (Tonry et al. 2003): 172 with changes from… * Knop et al, 2003, SCP : 11 new 0.4 < z < 0.85 reanalysis of 1999, Perlmutter et al. *15 / original 42 excluded/inaccurate colour measurements and uncertain classification * 6 /42 and 5/11: fail « strict  SNIA » sample cut * Barris et al, 2003, HZT: 22 new:varying degrees of completeness on photometry and spectroscopy records * Blakesly et al, 2003 : 2 with ACS on HST • + Low z : 0.01 < z < 0.15 • Calan-Tololo (Hamuy et al., 1996) : 29 • CfA I (Riess et al. 1999): 22 • CfA II (Jha et al, 2004b): 44

  32. A Dm=0.27 shift of low z data Use Kosmoshow by A. Tilquin! Shift z <0.15 data by Dm= 0.27  Wm= 0.43 +/-0.2 and WL= 0 +/-0.34 • No need for L • But Universe is not flat!

  33. The CFHT Legacy Survey Supernovæ Program SNLS http://snls.in2p3.fr/people/snls-members.html

  34. The CFHT Legacy Survey Supernovæ Program Canada and France (CPPM) Extra collaborators : VLT:ESO, Portugal, Sweden, UK. Keck:US. Gemini:UK, US.

  35. SNLS First year results with 71 SNIa astroph/0510447 to appear in A&A with CFHTLS and VLT, Gemini, Keck for spectroscopy At the end 700 SNIa!

  36. First results: Cosmological parameter fits • SNLS first year contours, combined with Baryon oscillation results (Eisenstein et al 2005)

  37. First results: numbers • For a flat LCDM cosmology • For a flat WM,w cosmology, • Combined with Baryonic acoutic oscillation (Eisenstein 2005) WM=0.263 +- 0.042 (stat) +- 0.032 (syst) WM= 0.271 +- 0.021 (stat) +- 0.007 (syst) w = -1.023 +- 0.090 (stat) +- 0.054 (syst) No surprise result! But better control of systematics

  38. Need for multiprobes to constraint w Ch. Yèche, A.Ealet, A. Réfrégier, C. Tao, A. Tilquin, J.-M. Virey, and D. Yvon.

  39. Stronger constraints thanks to correlations • For m-w0 and for w0-wa, we observe • orthogonal correlations between (CMB-WL) • and SNIa • It allows to break the degeneracies. • Actually we have 9-dim correlations, we gain more than the simple 2-dim overlap! • We use the full correlation matrix. 40

  40. Gravitationnal arcs Indication of Dark Matter in the Universe

  41. Weak Lensing effects A. Réfrégier Distorsion of background images by foreground matter Without lensing Lensing effect

  42. “Weak Lensing” A. Réfrégier Deformation matrix: • Direct measure of mass distribution in the Universe Other methods measure light distribution

  43. Principles of “Weak Lensing” Deformation matrix: Convergence: Shear Critical surface density Weak lensing:  << 1 (linear approximation) Measure shear  and solve for projected mass 

  44. “Shear” measurement Quadrupole Moments : Ellipticity: Shear: Relation:

  45. Acoustic series in P(k) becomes a single peak in x(r)! Pure CDM model has no peak. Warning: Correlated Error Bars Baryon acoustic oscillations from SDSS LRGs 0.2 < z < 0.5 CDM with baryons is a good fit: c2= 16.1 with 17 dof.Pure CDM rejected at Dc2= 11.7

  46. The Golden age of Cosmology HST map of the sky The Elementary block: a Galaxy From COBE to WMAP to Planck Surveyor

  47. Cosmology today … and tomorrow SNLS, ESSENCE, SNIFS, CSP, … Weak Lensing, CFHTLS, DUNE

  48. Is particle physics useful outside the lab?  YES! • Tune Kamae: Turning the Cosmos into a Particle Physics Lab OR/AND: using particle physics to understand the X-Cosmos

  49. c - n, g, p, e+ The Golden age of « astro particles » experiments

  50. Neutrino mass from Cosmology? All upper limits 95% CL, but different assumed priors ! Slide from Ofer Lahav

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