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5/18/2012 1

Grand Unified theory, God Particle and the

Missing Universe

Presented by

Abraham A.

Christian College

Chengannur

5/18/2012 2

Warning What you will hear in this session may alter your perception of reality and the universe itself. Please stay awake.

However, just in case you sleep, don’t snore.

5/18/2012 3

Fundamental interactions of nature

1/32

5/18/2012 4

Mediating particle concept

2/32

5/18/2012 5

Fundamental interaction characteristics

3/32

5/18/2012 6

The Elementary world

4/32

Mesons (2 Quarks) Baryons (3 Quarks)

Leptons(Irresponsive to Strong forces)

Hadrons(Responsive to Strong forces)

Matter

5/18/2012 7

Just a few of them ! 5/32

5/18/2012 8

I can’t remember them all !! 6/32

"Young man, if I could remember the names of these

particles, I would have been a botanist !”

-Enrico Fermi to his student Lederman

(both Nobel laureates)

5/18/2012 9

The Leptons

7/32

5/18/2012 10

8/32

Q.Which is the most abundant Matter particle in the universe?

The neutrino

5/18/2012 11

So many of them ! 9/32

1014 neutrinos

per second from Sun

are zipping through you

n

Every cm2 of Earth surface is crossed every second by more than 10 billion (1010) neutrinos produced in the Sun

No worries!

Neutrinos do not harm us.

Our bodies are transparent to neutrinos.

5/18/2012 12

10/32

The puzzling neutrinos o Near zero mass oAlmost no interactions (only weak)

o Can cross light-years of material without being affected o Can travel from the most remote corners of the Universe bringing information from the origin of space and time

They do matter to us: If there were no neutrinos the sun would not shine!

5/18/2012 13

The Solar Neutrino mystery

11/32

R. Davis: Measuring the solar neutrino flux in a gold mine in South Dakota for 30 years (1969-1999)

…and observing only 1/4 of the expected flux!! Why?

5/18/2012 14

The mystery solved-Neutrino oscillations

nm

nt

A detector here

does sees only nm

A detector here

sees only n t

The neutrinos change from one kind to another through neutrino oscillations. Thus the expected reaction does not occur at the calculated rate.

11/40 11/40

12/32

5/18/2012 15

13/32

Discovery of neutrino oscillation in the Super-Kamiokande (1998)

o Half of the nm are lost! Oscillated to undetected nt

o Neutrons have negligible but non-zero mass

Koshiba (Super Kamiokande Spokesman) : 2002 Nobel Prize [shared with R.Davis]

5/18/2012 16

14/32

5/18/2012 17

15/32

Internal structure of Hadrons

o Uneven internal distribution of charge.

o Two or three intense charge regions. o Internal Quark structure inferred. o Quark + Anti-Quark structure for Mesons. o Three Quark structure for Baryons.

5/18/2012 18

16/32

Generations of Quarks

Generations of Quarks are progressively heavy and require greater energy for production

5/18/2012 19

17/32 Colors of Quarks

oDifferent colors of Quarks can co-exist even if they have the other quantum numbers same.

oBaryons with three colors of Quarks have no resultant color (in analogy with optics) . o Mesons also have no color due to color + anti-color addition.

5/18/2012 20

18/32

Quark structure of some Hadrons

Proton Neutron

Omega Hyperon

5/18/2012 21

19/32

Occurrence of Quarks

o Quarks have not been found in isolation. o Quark confinement prevents their separation.

oThe phenomenon follows from the theory of Quantum Chromo dynamics (QCD) o Forced Energetic separation of Quarks produce two new pairs of quarks.

5/18/2012 22

Quark confinement • There are no free quarks, quarks and anti-quarks are “confined” in colourless doublet (mesons) or triplets (baryons) by the exchange of gluons

The new quarks bound to the old quarks and form new mesons

Here, the gluon connection snaps, and other quark-antiquark pairs are created out of the energy released

Gluon hold quarks together as they move further apart

Z0

Decay

® S.Ward

20/32

5/18/2012 23

Fundamental interactions Once more

21/32

5/18/2012 24

Unification stage-1 Electroweak force

22/32

Glashow, Weinberg and Salam (GWS, 1961 – 1968 ) developed a theory that unifies the electromagnetic and weak forces into one electroweak force.

The Exchange particles are four Bosons generated

through symmetry breaking

oZ

oW+

oW-

oPhoton

5/18/2012 25

Unification stage-2 Standard Model success

23/32

o Electroweak + strong

o All matter constituents

o 6 quarks and 6 Leptons

o Structure of matter ~10-18 m

o Pioneers awarded 20 Nobel prizes.

5/18/2012 26

Unification stage-2 Standard Model constituents

24/32

5/18/2012 27

Unification stage-2 Higgs field & God Particle

25/32

oHiggs field exists every where

oThe field imparts mass to particles while breaking symmetry

oMass α Field interaction

oInteraction mediated by the Higgs Boson

Ho

5/18/2012 28

Unification stage-2 Search for the Higgs Boson

26/32

oThe energy of the particle is >> Tev/c2

oIt is hoped that the LHC will produce the God particle

5/18/2012 29

Unification stage-3 The Grand Unification

27/32

5/18/2012 30

Unification stage-3 The GUT symmetry

28/32

S’ =S+ (1/2)

5/18/2012 31

The Land Marks in unification

29/32

5/18/2012 32

The fate of the Universe

30/32

5/18/2012 33

Composition of the Universe

31/32

5/18/2012 34

The Missing Universe

32/32

Chart of the matter of the universe-In a way, this chart is an embarrassment for scientists. We are only able to account for 4% of the matter in the universe.

5/18/2012 35

THANK YOU

isureshabraham@gmail.com

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