Gravitation Hartmut Abele Sommersemester 2006

Präsentation zum Thema: "Gravitation Hartmut Abele Sommersemester 2006"—  Präsentation transkript:

1 Gravitation Hartmut Abele Sommersemester 2006
L & G As you have already seen in the other talks, , neutrons are quite multi-purpose particles The topic I would like to present today is In this talk, I will concentrate on the topic particle physics with neutrons. Particle physics deals basically with the ultimate constituents of matter and the interactions between them. Neutrons are necessary for two reasons:first Some observables rely on neutron physics, for other questions the neutron provides one of several ingredients. The second reason is: Neutrons are in abundant supply. At the european neutron source, the production rate is 10^15 n/cm^2/s and we have highest statistical sensitivity . Particle physics is about particles and their interactions, Neutrons are good tools, because they take part in all four fundamental interactions The ultimate aim of particle physics is to derive the basic laws of physics. The problem is : we have two theories and they have been quite separated in the past: First there is the Theory of gravitation, the theory of the large and very large, describing the planetary motion and galaxy clusters very successfully. With neutrons, we go the other way around. We test graviation at the micrometer scale and , experiments with neutrons at the ILL in Grenoble, the european neutron source, and we test the Standard Model of elementary particle physics. these experiments have, as you can imagine, something to do with the SM, the accepted theory of particles and interactions With neutrons we lean something about the SM, in neutron decay all particles of the first quark generation are involved, we can compare our results with the results from high energy physics and we can see if we get a consistent picture of the SM. This is not the case right now, an we think, that this has something to do with the first quark generation. So I could add: Is unitarity violated in neutron decay.

2 Präsentationsfolien, 25. April 2006
Hartmut Abele

3 Quests in Fundamental Physics
Gravity Strong interaction Electro- magnetism Weak interaction Lämmerzahl, Graduiertentage Heidelberg 2003 Hartmut Abele

4 Knowledge of a basic law of physics
Two Theories: Theory of Gravitation: General Relativity Quantum Theory: Standard Model Derived from simple symmetry principles High energy particle Physics Tera-eV Neutron Nano-eV Hartmut Abele

5 100 GeV, LEP-energy at CERN  = 1/128  = 1/137 Hartmut Abele

6 MPL MnPL GUT quantum gravity 100 GeV, LEP-energy at CERN  = 1/128
 = 1/137 quantum gravity MnPL Hartmut Abele

7 ART im Alltag: Global Positioning System (GPS)
MHz instead of MHz Hartmut Abele

8 2 Säulen: Quantentheorie Relativitätstheorie Hartmut Abele

9 Hartmut Abele

10 Kuiper belt Hartmut Abele

11 Gravitation im Großen Hartmut Abele

12 Gravitation bei großen Abständen
Hartmut Abele

13 ... sehr große Abstände Hartmut Abele

14 Vom Aristotelesschen Zentrum der Welt bis zum Big Bang
Hartmut Abele

15 Gravitation im Kleinen: Gravitation und Quantenmechanik
Phasenverschiebung in Neutronen, Atomen Gebundene Quantenzustände im Gravitationsfeld der Erde QCD String Theorien Hartmut Abele

16 Rauch et al. Hartmut Abele

17 COW-Experimente 1975 erstmalige Beobachtung einer Gravitations-Induzierten Phasenverschiebung bei Materiewellen von Colella, Overahauser und Werner Verwendet wurde ein Neutroneninterferometer, das aus einem Einkristall gefräst wurde Hartmut Abele

18 COW-Experimente Schematischer Versuchsaufbau
= Rotationswinkel = Richtung einfallender Strahl und Rotationsachse = Braggwinkel = Neutronendetektoren Abhängigkeit der relativen Phase vom Rotationswinkel: Hartmut Abele

19 COW-Experimente gleiche Phasenverschiebung auf den Pfaden AC und BD
Ist kommt es zu einer relativen Phasendifferenz auf den Pfaden AB und CD S Hartmut Abele

20 COW-Experimente Ergebnis des ersten Experiments von 1975
Integrationszeit pro Meßpunkt: 80 Minuten Hartmut Abele

21 Grundlegende Fragen? mehr als 1000x zitiert in den letzten 5 Jahren, geordnet nach Häufigkeit: Particle Data Booklet (unzählig viele Zitate), Teilchenphysik WMAP, 3K Hintergrunstrahlung (3175), Kosmologie Massenhirarchie und Extradimensionen (2749) superconformal field theories and supergravity (3829) Measurements of omega and lambda from 42 high redshift supernovae (2635) The Hierarchy problem and new dimensions at a millimeter (2715) New dimensions at a millimeter to a Fermi and superstrings at a TeV (2049) First results from KamLAND: Evidence for reactor anti-neutrino disappearance (1060) Hartmut Abele

22 Grundidee: Gravity and Space Time
SM, Electromagnetism Gravity String Theory and Extra Dimensions The Problem is related to the number of dimensions of space and time. It is obviously … The Forces of the standardmodell are local transformations in space. But there is a fundamental difference to Gravitation. Gravitation is the deformation of space time. The best method to reconcile Gravity and SM are string theories. It is worth mentioning that string theory is the only theory making a prediction about the number of dimesnsions. It is not 3 it is 11. Obviously there are extradimensions. And the reason way we don’t see them is the assumption that there dimesnions are curled to a cylinder or a torus – we say they are compacified and the comfactification radius is small. Under certain assumptions they predict a deviation from the gravity law, from newtons law at small distances say one micron or so, exactlly in the range of our experiment. Hartmut Abele

23 Newton:Brief an Bentley, 25.2.1692
Hartmut Abele

24 Graduiertentage 2003 (Lämmerzahl): Reasons for new interest
New experimental devices Ultrastable cavities Lasers Frequency comb SQUIDs Space experiments (GP-B, MICROSCOPE, ACES, SUMO, PARCS, RACE, STEP, OPTIS) New space related techniques (drag free, grav. sensors) Violations predicted by quantum gravity Modification of Maxwell equations Modification of Dirac equation Yukawa modification of Newton potental Hartmut Abele

25 Überblick Gravitationstheorien Newton Einstein: ART
Aristoteles, Galilei, Kepler: Rotationskurven Galaxien: Dark Matter I Newton: G - Bestimmung Newton Test 1/r im Sonnensystem 1:1012 Pioneer-Anomalie r kleiner 1 mm Einstein: ART Klassische Tests: Merkur, Lichtablenkung etc. Kosmologie, Kosmologische Konstante, zeitabh. der Kopplungskonstanten Gravitationslinsen Aequivalenzprinzip Hartmut Abele

26 Überblick Schwache Gravitationsfelder Starke Gravitationsfelder
Non-Newton bei kleinen Abständen Große Extradimensionen und die Frage nach der Dimensionalität der Raumzeit Quantenzustände im Gravitationsfeld der Erde Suche nach Gravitomagnetismus, Lense-Thirring-Effekt Starke Gravitationsfelder Pulsare, Doppelpulsare Gravitationswellen Schwarzes Loch Hawking-Strahlung Quantentests der ART Hartmut Abele

27 Wiederholung zum 2. Mai 2006 Krümmung im Riemannschen Raum
s. Gravitation, U.E. Schröder, s. 30 Hartmut Abele

28 Kugel Hartmut Abele

29 Gauss-Kruemmung Hartmut Abele

30 Zwei geodätische Oberflächen durch den selben Punkt
Hartmut Abele

31 Hartmut Abele

32 John Wheeler, Gravitation und Raumzeit, S.69
Ein Bumerangflug durch die Erde Hartmut Abele

33 Krümmung, die Sprache der Gravitation Hartmut Abele

34 Hartmut Abele