Unsolved Mysteries of Physics

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Unsolved Mysteries
(of Physics)
The Speakable and the Unspeakable
Weldon J. Wilson
Department of Engineering and Physics
University of Central Oklahoma
Edmond, OK 73034-5209
cyberphysics.com/wwilson
wwilson@uco.edu
The Speakable
96% of matter/energy is a mystery. It
has never been observed even in our
best laboratories or observatories!
Dark Energy
1
2
m v0 
2
GMm

r0
1
2
mv 
2
GMm
r

Should
v 
slow down
 1 1
2
v0  GM   
 r0 r 
Speeding
Up !!!
The Speakable
Dark energy appears to be the dominant component of the
“Right now,Universe,
not only for cosmology
but is no persuasive theoretical
physical
yet there
for elementary particle theory, this is the
“Basically, is,
people
don’t with
have a
explanation.
The
acceleration
of the Universe
along
bone in our throat.”
- Steven
Weinberg
clue as to how to solve this
dark matter, the observed phenomenonproblem.”
which- most
directly
Jeff Harvey
demonstrates that our fundamental theories of particles
is the biggest
and gravity are either‘This
incorrect
or incomplete. Most experts
embarrassment in
believe that nothing short
of physics”
a revolution in our
theoretical
- Michael Turnerphysics will be required to
understanding of fundamental
achieve a full understanding of the cosmic
acceleration.
For
“… would be
No. 1 on my
list of things to figure out.”
these
reasons,
the
nature of dark energy
ranks among the
“… Maybe
the most
fundamentally
- Edward Witten
thing in basic science.”
verymysterious
most compelling
of all outstanding
problems in physical
Frank Wilczek
science.
Dark Energy Task Force (DETF) astro-ph/0609591
All the Current Theories of
Dark Energy
There are none!
The Speakable
80% of all matter is a mystery. It’s
effect is seen only in gravitation.
Fritz Zwicky
Caltech Professor of Astrophysics
(1927-1968)
Tech Director Aerojet Engineering
(1941-1961) – "father“ of modern
jet engine
• 1929 – Introduced “tired light” hypothesis to
explain Hubble Red Shift
• 1931 – Introduced idea of exploding star origin
of cosmic rays – supernova/neutron star
• 1933 – Introduced idea of Dark Matter
• 1937 – Gravitational Lens
Zwicky
von Kármán
Malina
Parsons
1936 – Founded (along with Theodore von Kármán, Frank
Malina, Jack Parsons) the Guggenheim Aeronautical
Laboratory at the California Institute of Technology (GALCIT)
that in 1943 became the Jet Propulsion Laboratories (JPL)
1943– Founded (along with Theodore von Kármán, Frank Malina,
Jack Parsons) the Aerojet Corporation
19612-1968 – Published a comprehensive six volume Catalogue
of galaxies and of clusters of galaxies.
F  ma
Basic Idea
GMm
R
2
m
v
2
R

v 
GM
R
gravity
From this, you can calculate
the orbital speed, if you
know the mass of the galaxy
(Specifically the mass
inside the orbit)
NGC 3198
Zwicky proposes Dark Matter to explain
this discrepancy of theory with
observations. But what is it?
MACHO
???
MAssive Compact Halo Objects
Massive Compact HAlo Objects
Idea:
• Compact and dark objects
pervade the galactic halo.
• Look at distant stars
(Large Magellanic Cloud).
• Try to find when one
spontaneously brightens.
“Gravitational Lensing”
Far
Object
You
Intervening
Object
Baryonic Matter Summary:
The amount of dark baryonic matter can only
account for about 20% of the dark matter in the
Milky Way region.
And then only with substantial modification of
galaxy formation dynamics.
Goldwater
Manilow
White
Bonds
Non Baryonic Dark Matter Candidates
Hot Dark Matter
Cold Dark Matter
• Hot means high momentum
and typically light
• Cold means low momentum
and typically heavy
• Candidates
• Neutrinos (n)
• Discovered in 1998 to
have mass
• Recent studies show
they can only have 0.3%
of needed Dark Matter.
• Candidates
• New variant of neutrino
• Exotica
• Etc.
• New kind of particle
(supersymmetric
neutralino)
• WIMPS (Weakly
Interacting Massive
Particles)
Cold Dark Matter: Direct Searches
Very hard to do
WIMPS
• Approximately 1,000,000 pass through you every second.
• If they exist at all.
• The reason they are “Dark” is they
don’t interact much with ordinary matter.
• They will shake atoms when they (rarely) hit one.
• Atoms are always shaking due to heat.
• Your detector must be (nearly) infinitely cold.
Mordehai Milgrom
1983
Modified Newtonian Dynamics
MOND
What if Newton was wrong?
Newton said that Force was
proportional to Acceleration
• Proposed by Milgrom - 1983
• Heavily criticized thereafter
MOND
Suppose Newton was
right for large
accelerations, but for
small accelerations, his
formula breaks down?
Newton’s Law
MOND
Comments and Thoughts:
How does MOND go from one behavior
to the other?
F a
No Idea….
Why hasnt anyone else seen this
modification of Newton’s laws?
F a
MOND Modification
2
We’re talking very small accelerations
here…
1/100,000,000,000 × Earth’s
gravity…..
MOND: Modification of Newtonian
Dynamics
What if Newton was wrong?
F  ma
MOND

 ma

F 
m 2
a

 ao
a  a o
a  a o
a
m
a  F
a0
MOND: Basic Idea
centrifugal
=
gravity
centrifugal
m v 


ao  r 
2
2
=
r
gravity
v
2
G
Mm
=
2
 G M ao 
But does it work?
1/ 2
Fits to v (r) for both LSB & HSB Galaxies
Tully-Fisher
Relation
L  M
F  ma  G
Mm
r
a G
2
M a0
r
2
m
2
a
a
a0
2
v 
M a0
 
 G
2
r
r


2
v  G M a0
4
M O N D  T -F R elation!!
 v
4

Explanations
• Unseen (and
unobserved) exotic
matter
• WIMPs
• Currently
massive
searches
underway
• MOND
• Needs better
theoretical
motivation
Cat Fight
What is the prevailing wisdom?
•
No honest physicist will tell you
that they know.
•
Dark matter is popular because
particle physicists are looking for
a similar particle (for different
reasons)
•
MOND needs work. But there is
no disputing that it describes
galactic rotation curves (and
other stuff)
Summary/Speculation
• MOND has amazing ability to model data
taken after it was invented
• Excellent fits to galaxy rotation curves require
M/L(colour) as from SS theory
• Compelling evidence that negligible DM
interior to Sun
• Now limiting form of Lorentz covariant theory
• MOND really might be the next great step in
physics
The Unspeakable
The unspeakable refers to a “hidden evil whose
depth and deceit goes beyond the capacity of words
to describe.”
- Thomas Merton
Telstar
(1962)
Awarded Noble Prize in 1978
•
•
•
•
First Private Financed Satellite, (AT&T)
Transponder to relay One TV channel
or 12 multiplexed telephone signals
Frequency - 4 GHz
Solar Powered – 14 Watts!
Arno Penzias and Robert Woodrow Wilson
Discover Big Bang 1962
(2.73 K Blackbody Radiation)
Awarded Noble Prize in 1978
Arno Penzias doing real
experimental work
Telstar, 1962
COBE, 1989
WMAP, 2001
Absolute Motion Relative to the
Local Absolute Rest Frame
Absolute Motion
(relative to
background
radiation)
????
Local Absolute
Rest Frame
Moving toward Leo at ~375 km/s (0.12% c)
All the Current Scientific
Discussions and Papers on
the CBR Dipole Anisotropy
There are none!
Extra Credit
• Propose a model that explains Dark Energy
(Any model will do – reasonable or not)
• Discover what Dark Matter consists of and/or
place MOND on good theoretical basis
• Explain CBR Dipole Anisotropy within the
current Paradigm
(Any discussion will do – reasonable or not)
Deadline: None.
References
•
•
•
•
Bekenstein J., Milgrom M. ApJ, 286, 7 (1984).
Milgrom M., ApJ, 270, 365 (1983).
Milgrom M., ApJ, 270, 371 (1983).
Nicolson , Iain , Dark Side of the Universe: Dark Matter,
Dark Energy, and the Fate of the Cosmos, ISBN:
0801885922 , (2007).
• Pendle, George, Strange Angel: The Otherworldly Life of
Rocket Scientist John Whiteside Parsons.
ISBN: 015100997X (2005).
• Shaw, Mark, Beneath The Mask of Holiness –Thomas
Merton and the Forbidden Love Affair that Set Him
Free. ISBN: 0230616534 (2009).
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