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Building Blocks of the Universe 13.75 ± 0.11 billion years in couple of hours Mohammad Ahmed, TUNL.

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Presentation on theme: "Building Blocks of the Universe 13.75 ± 0.11 billion years in couple of hours Mohammad Ahmed, TUNL."— Presentation transcript:

1 Building Blocks of the Universe 13.75 ± 0.11 billion years in couple of hours Mohammad Ahmed, TUNL

2 What are the building blocks of the Universe? Building blocks means fundamental units of a given instance in a multiverse A Universe is all that exist and can exist A Universe is space, time, matter, energy, constants, and the governing principle A close approximation of the governing principle is what we call set of universal laws (e.g., ma = F)

3 Our understanding of the universe Laws are formulated from the need to explain the observations and they carry the power of prediction Constants are special numbers which play a role in formulating laws. We do not know how the constants come into being and why do they have the values they do. Each universe may have its set of constants called universal constants Space-time, matter, and energy are all knitted in a fabric which defines the past, present, and the future “events”.

4 Physical Laws as Building Blocks of the Universe

5 The laws approximating the governing principle Q1Q1 Q2Q2 r q

6 Symmetries and their consequences Energy Momentum Angular Momentum Time Space Angles Reflection (Parity), Charge Conjugation, Isospin Conservation Laws

7 The conservation laws Hamiltonian invariance under space translation Is the conservation of momentum

8 Laws and Theories Laws of motion, Coulomb’s Law, Law of Gravitation, etc Aggregate of laws paint a picture of a theory A theory is a collection of statements (or equations) which are all defined to be true All theories unified is the best approximation of the governing principle of this universe

9 Theories of large and small distance scales

10 Our current understanding of theories


12 Electromagnetic Interactions Q Weak Interactions W Strong Interactions S Gravity G Electro-Weak GUT TOE ? ? Energy ( q = 10 15 GeV )

13 Constants as Building Blocks of the Universe

14 Constants Depending on who do you talk to, you will get a different number of “universal constants” Dimensional Dimensionless NIST accepted number of universal constants is about 8

15 Constants An example of dimensional constant The speed of light c [c] = [L] / [T] c = 299792458 m/s

16 Constants An example of dimensionless constant The fine structure constant   = 1/137

17 Constants The eight universal constants ConstantValueUnits Z0Z0 376.730313461  00 8.854187817 x 10 -12 F/m 00 4  x 10 -7 N/A 2 G6.67384 x 10 -11 m 3 /kg s 2 h6.62606957 x 10 -34 J s c299792458m/s e1.602176565 x 10 -19 C  7.297352 x 10 -3

18 Constants Are they really constant, i.e., not changing in time? Time variability of  over 2 billion years -0.11<  <0.24 x 10 -7 C. R. Gould, Oklo Reactor Data Analysis (1.7 Billion Years, few hundred thousand years life of natural fission reactor near Gabon, Africa.

19 Constants Constants and Observational Multiverse  can be described by e, , h, c If e, , h, c were different in another universe, however, they adjusted their values such that  still comes out to be 1/137, this universe will be observationally similar to our universe

20 Constants Different set of fundamentally pure numbers gives rise to different instances of universe within a multiverse

21 Building blocks of seen and unseen universe: Space-time, matter and energy

22 Minkowski diagram and Space-time (ct,x 1,x 2,x 3 ) Inside = time-like Along = light-light Outside = space-like Worldlines and imaginary mass in space-like region

23 Space-time curves and geodesic Light travels along the shortest path between two points in space-time This path is called a geodesic If a geodesic is curved, light travels in a curved space Curved space-time is gravity

24 Curved space-time and orbits



27 Organization of Matter


29 Major Events in the history of the universe Hadron Era 10 -6 s 10 12 K n/p set Lepton Era 10 0 s 10 11 K n  p + e - + e Photon Era 10 1 s 10 10 K kT BBN Era 10 2 s 10 9 K 2 H, 3 He, 4 He, 7 Li CMB Era 10 12 s 10 3 K Transparent Universe


31 Wilkinson Microwave Anisotropy Probe WMAP Results

32 Wilkinson Microwave Anisotropy Probe Age of universe is 13.73 billion yearscto within 1% Curvature of space is within 1% of "flat“ Ordinary atoms make up only 4.6% of the universe (to within 0.1%) Dark Matter makes up 23.3% (to within 1.3%) of the Universe Dark Energy makes up 72.1% of the universe (to within 1.5%), causing the expansion rate of the universe to speed up

33 Wilkinson Microwave Anisotropy Probe

34 The organization of the visible universe


36 N-N Interactions


38 e Hydrogen Can we make a Helium nucleus by adding a proton ?

39 e Hydrogen Electrostatic force will oppose it Yes you can, but … You will have to throw the proton at a very high speed

40 e Hydrogen How does this happen ? Fast

41 e EM repulsion increases Still not within the range for the nuclear force to take over How does this happen ?

42 e EM repulsion still increases Bosons which mediate nuclear force start to reach the incoming Fermion (the other proton) and “catch it” Bosons for Strong NF Start to Exchange

43 Short Range NF A Helium nucleus is formed !

44 A 2 He nucleus is formed !  Pions (or more generally mesons) keep two nucleons together in a nucleus

45 e Hydrogen No EM repulsion ! Distance is still too large for strong NF to act, “not in the range to catch”. How about adding a neutron ?

46 e Hydrogen You can bring it in slowly !!! How about adding a neutron ?

47 e Even a neutron at rest will be captured !

48  A 2 H nucleus requires less energy to make than a 2 He nucelus

49 How about comparing 3 He and 3 H? We know the EM part of the force is different. If we account for It, can we calculate the binding energies with simple 2-body NF?

50 No !! We get the answer wrong, i.e., measured and calculated binding energies are different ! There seems to be another type of NF present  3-NF

51 Understanding N-N interactions (Fermi’s Golden Rules)

52 TME Physics of Interaction Cross Section DOS

53 Understanding N-N interactions (Feynman) Time Space b) M fi ~  c) M fi ~  

54 Understanding N-N interactions (Phase)



57 Understanding N-N interactions (Potential)

58 Understanding N-N interactions (Mesons)


60 2NF 2NF,3NF2NF,3NF,4NF Can we predict the observables associated with the ground state properties (e.g., binding energies, etc), and the dynamics of their interactions (e.g., cross sections, analyzing powers, etc.) Ideal Laboratories for Few-Body Studies in NP Understanding N-N interactions

61 Duke Free-Electron Laser Lab. (HIGS) Tandem Laboratory The Local Accelerator facilities


63 EeEe EE E Laser Electrons For example Man-made – Compton Backscattered  -Ray Sources

64 How HIGS Works

65 May 27 nd, 2009REU Lecture 65 Booster Injector LINAC RF Cavity Mirror Optical Klystron FEL The High Intensity Gamma-Ray Source

66 HIGS Parameters

67 The Tandem

68 Tandem Parameters LENA is another accelerator

69 Nuclear Physics @ TUNL Fundamental understanding of the building blocks on this universe (Basic Nuclear Physics) Greater good of the community (Applied Nuclear Physics)

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