Building Blocks of
the Universe
13.75 ± 0.11 billion years in
couple of hours
Mohammad Ahmed, TUNL
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)
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”.
Physical Laws as
Building Blocks of the
Universe
The laws approximating the governing principle
q
Q1
r
Q2
The laws approximating the governing principle
Symmetries and their consequences
Conservation Laws
Energy
Time
Momentum
Space
Angular Momentum
Angles
Reflection (Parity), Charge Conjugation, Isospin
The conservation laws
Hamiltonian invariance under space translation
Is the conservation of momentum
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
Theories of large and small distance scales
Our current understanding of theories
Our current understanding of theories
Our current understanding of theories
Energy (q = 1015 GeV)
G
Gravity
?
TOE
S
Strong Interactions
GUT
W
Weak Interactions
?
Electro-Weak
Q
Electromagnetic
Interactions
Constants as Building
Blocks of the Universe
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
Constants
An example of dimensional constant
The speed of light c
[c] = [L] / [T]
c = 299792458 m/s
Constants
An example of dimensionless constant
The fine structure constant a
a = 1/137
Constants
The eight universal constants
Constant
Value
Units
Z0
376.730313461
W
e0
8.854187817 x 10-12
F/m
m0
4p x 10-7
N/A2
G
6.67384 x 10-11
m3/kg s2
h
6.62606957 x 10-34
Js
c
299792458
m/s
e
1.602176565 x 10-19
C
a
7.297352 x 10-3
Constants
Are they really constant, i.e., not
changing in time?
Time variability of a over 2 billion years
-0.11< Da/a <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.
Constants
Constants and Observational
Multiverse
a can be described by e, e, h, c
If e, e, h, c were different in another universe, however, they
adjusted their values such that a still comes out to be
1/137, this universe will be observationally similar to our
universe
Constants
Different set of fundamentally pure
numbers gives rise to different
instances of universe within a
multiverse
Building blocks of seen and unseen
universe: Space-time, matter and
energy
Minkowski diagram and Space-time
(ct,x1,x2,x3)
Inside = time-like
Along = light-light
Outside = space-like
Worldlines and
imaginary mass
in space-like
region
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
Curved space-time and orbits
Curved space-time and orbits
Curved space-time and orbits
Organization of Matter
Major Events in the history of the universe
Hadron Era 10-6 s 1012 K n/p set
Lepton Era 100 s 1011 K n  p + e- + ne
Photon Era 101 s 1010 K kT
BBN Era
102 s 109 K
2H,3He,4He,7Li
CMB Era
1012 s 103 K Transparent Universe
Wilkinson Microwave Anisotropy Probe
WMAP Results
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
Wilkinson Microwave Anisotropy Probe
The organization of the visible universe
The organization of the visible universe
N-N Interactions
Can we make a Helium nucleus by adding a proton ?
Hydrogen
e
Yes you can, but …
Electrostatic force will oppose it
Hydrogen
e
You will have to throw the proton at a very high speed
How does this happen ?
Fast
Hydrogen
e
How does this happen ?
EM repulsion increases
e
Still not within the range for the nuclear force to take over
Bosons for Strong NF Start to Exchange
EM repulsion still increases
e
Bosons which mediate nuclear force start to reach the incoming
Fermion (the other proton) and “catch it”
A Helium nucleus is formed !
Short Range NF
A 2He nucleus is formed !
p
Pions (or more generally mesons) keep two nucleons
together in a nucleus
How about adding a neutron ?
Hydrogen
No EM repulsion !
e
Distance is still too large for strong NF to act, “not in the range to catch”.
How about adding a neutron ?
You can bring it in slowly !!!
Hydrogen
e
Even a neutron at rest will be captured !
e
A 2H nucleus requires less energy to make than a 2He nucelus
p
How about comparing 3He and 3H?
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?
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
Understanding N-N interactions (Fermi’s Golden Rules)
Understanding N-N interactions (Fermi’s Golden Rules)
TME
Physics of Interaction
DOS
Cross Section
Understanding N-N interactions (Feynman)
Time
Space
b) Mfi ~ a
c) Mfi ~ a2
Understanding N-N interactions (Phase)
Understanding N-N interactions (Phase)
Understanding N-N interactions (Phase)
Understanding N-N interactions (Potential)
Understanding N-N interactions (Mesons)
Understanding N-N interactions (Mesons)
Understanding N-N interactions
• 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.)
2NF
2NF,3NF
2NF,3NF,4NF
Ideal Laboratories for Few-Body Studies in NP
The Local Accelerator facilities
Duke Free-Electron Laser Lab.
(HIGS)
Tandem Laboratory
Man-made – Compton Backscattered g-Ray Sources
Ee
Electrons
El
Eg
For example
Laser
How HIGS Works
The High Intensity Gamma-Ray Source
RF Cavity
Optical Klystron
FEL
Booster Injector
Mirror
May 27nd, 2009
LINAC
REU Lecture
65
HIGS Parameters
The Tandem
Tandem Parameters
LENA is another accelerator
Nuclear Physics @ TUNL
• Fundamental understanding of the building
blocks on this universe (Basic Nuclear Physics)
• Greater good of the community (Applied Nuclear
Physics)