Transcript Document

by
T. L. Yoon, School of physics
University of Melbourne
Talk given in Geoff Opat seminar series,
6 Sept 2002
Manifestation of mirror matter
•Why mirror matter?
•How mirror matter interact with
ordinary matter
•Interaction of mirror space
bodies (MSB) with atmosphere
•Comparison of Ordinary SB (OSB)
and MSB
•Manifestation of Small MSB
•Manifestation of Large MSB
•Finding mirror matter from the
ground
Theoretical motivation for
Mirror Matter
•Parity is broken in SM
•Elegance suggests it shouldn’t
•EPM by Foot, Volkas and Lew,
1991, GEPM = GSM  G’
•Exact Parity Model restores
exact parity by demanding
MIRROR MATTER to exist
Mirror particles
 have
the same mass as SM particles
 interact with each other with
Mirror SM interactions
 singlet under SM
 Stable
 scarce at the scale of solar
system
 But could dominate over ordinary
matter in a larger scale
How do they interact with us ?



Via gravity
Via mirror-ordinary
mixing in the neutral
sectors, Lint
The mixing effects can
be probed by experiments
Lint allows us to see the
mirror world via:
Higgs – mirror Higgs mixing
(II)Maximal Active – mirror
neutrino mixing
(III)photon-mirror photon kinetic
mixing - a suppressed EM
interactions
(I)
Photon-mirror photon kinetic
mixing
e
L
g’- g
= e Fmn F’mn
•Sign of e not known theoretically
•Mirror electron is seen as an tiny
charge of magnitude ee
An exotic possibility
 asteroids/comets
(space bodies)
are potential mirror matter in
the solar system
 What
happen if such mirror space
bodies (SB) hit the Earth at
11 km/s  vi  70 km/s?
 R.
Foot, T. L. Yoon
Acta Phys. Polon. B33 (2002)
1979-2009; astro-ph/0203152
Will there be any effect if
MSB hit Earth?
If e
= 0, no effect unless
gravitationally alter the
Earth orbit
Orthopositronium experiment
suggests  e   10-6
have physical effects when
mirror SB plummeting through
atmosphere
The potential of mirror nucleus
seen by ordinary air atom Ze are
suppressed e = 10-6
4e 2 M A2 e 4 Z 2 Z '2
d coll

2
d

1
2 2
2
 4 M Av sin
 2 
2 r0 

•Rutherford scattering even at
vi ~ 11 – 70 km/s
•(ordinary atoms need v > 1000
km/s for Rutherford scattering)
FOR MSB ONLY
Kinetic energy of all molecules in
the swept column gets “ scooped”
and thermalised within the mirror
SB + co-moving air capsule via
Rutherford scattering.
Resultant atmospheric
drag force slows the SB
dE
2
 -C d  atm Sv
dx
Drag
force is roughly the same
as if it were made of ordinary
matter
A standard result for both MSB
or OSB
Approximate solution for v
v
= viexp(-x/D),
velocity decay exponentially
 D = x / (atmS/MSB)dx
 D ~ 10(R/5m)(SB/gcm-3)km
 SB of size < (5-10)m loses its
astrophysical velocity after
x ~ D
 ‘stopped’ = arrive at ~
0.3 – 1 km/s (terminal velocity)
Comparison (small sized SB)
Ordinary SB
Mirror SB
Air molecules don’t
penetrate into SB
Energy dissipate only
on surface


Surface melts rapidly



Bright at higher
altitude (before losing
vi)
 Bright at low altitude
Dark flight at low
as density of air
altitude (after losing
increases
vi)




Air molecules penetrate
into SB
The entire SB + comoving air capsule is
heated up internally
slower surface melting
(compared to OSB)
Dimmer at higher
altitude
What kind of small MSB can
survive without completely
melted in the air?
 calculate
the energy absorbed
per mirror atom by the MSB
throughout the journey, e~SB
 Compare
with the heat per
atom required to melt
them, e m
Calculation
MSB absorbs the kinetic energy from
the air molecule in the column from
x = infinity -> xd above ground:
1

fn(h) M Av 2 Sdx  Energy absorbed when
2


~
de SB 
, swiping a column of Sdx
N SB
M Avn(h)Sdx 
dv  M SB
Slowing down of MSB due
to air’s drag force
f = fraction of E heating the SB
~ 0.1? A difficult hydrodynamical
problem, uncertain
 Integrate
v = vi
from
to v = 0, (‘stopped’)
 M A'
~
e SB  f 
 18 M P
~
If e SB < e m
 v i 

 5eV
 11km / s 
2
the small MSB
will not melt in air
In unit of
eV/mirror
molecule
From the table:
A
small MSB can possibly survive
to hit the Earth’s surface
provided that it is made of nonvolatile composition (mirror
rocky silicate materials) or
mirror iron materials
 No small mirror ice SB survives
Anyone ever seen such
exotic event?
 extra-planetary
low-altitude
fire-ball
 v (at low altitude)~ 0.1 – 3
km/s
 not luminous at high
altitude
 survive to hit the surface
yet left no trace on ground
Yes, they have been
seen!!!
 Maybe
at a rate around once a
month, but mostly not reported
 Scientifically documented by
meteorite experts
 Spanish event – Jan 18, 94,
Santiago de Compostela
 Jordan event – April 18, 2001
 Poland event – Jan 14, 1993
 etc…
Induced charge of mirror
electron depends on the
sign of e
 Mirror
Matter may be buried
underground in these highly
localised impact sites!!!
 Physical properties of
mirror matter determined by
the sign of e
Two possibilities of
e
= + ve:
Electrostatic
repulsion
between mirror
atoms and
ordinary atoms
e
e
= - ve:
 Electrostatic
attraction
between mirror
atoms and
ordinary atoms
If e +ve :
 Solid
mirror does not ‘penetrate’
ordinary solid matter
 Weight of mirror matter can be
supported by induced mirrorordinary EM repulsion
F
- 6  10
~ 10 
EM
Fmax
 e
gravity
 Mirror
-6
 N SB

 N A
1/ 3



matter largely unmixed with
ordinary matter
Or, maybe the sign of e is
negative ?
Non-trivial solid-state problem and
more speculative
 Energetically favourable for mirror
matter to be completely immersed in
ordinary matter
 Releases energy in the process
 Mirror fragments penetrate deeper
below the ground
 Could mix with ordinary matter
 So we don’t see them on the ground

Tunguska event can also be
explained by MSB
The 1908 Tunguska explosion
 Siberia,
Russia
14' 28'' UT, June 30th 1908
 Hugh explosion at an low altitude
of 5 – 8 km above ground
 1000 atomic bombs equivalent
 devastated 2000 km2 of Siberian
taigà,
 felling more than 60 million
trees
 0h
• Besides a predominant major
explosion, also has a number
of smaller scale low-altitude
explosions (maybe even right
above the surface)
• But no SB fragment found (over
40 science expeditions)
was the Tunguska SB a
asteroid?

Only asteroid has strong mechanical
strength to survive at low altitude
problems with asteroid
interpretation:
1. Should give multiple major
explosions
2. Should left SB fragment on ground



1,2 not found
Amusingly advocated mainly by nonSoviet block scientists
Or, maybe it was a volatile
comet?
 Comets’
elliptic orbit suggests vi
> 30 km/s (large entering
velocity)
 How could it survive to low
altitude before breaking up?
 Still some SB remnant is expected
(comets also contain non-volatile
materials)
 musingly advocated mainly by
Soviet block scientists
Tunguska caused by a MSB
WITH R >> 10m?
v ~ constant
Heat dumped into MSB (per mirror
molecule) at height xd above
ground is
 5f
~
e SB ( xd )  
 cos 
 - xd cos 
exp 
h0

 M A'

 18 M P
 100m  g / cm


 R   SB
3

v


 
 30km / s 
3

eV

h0  8km (scale height of atmosphere)
Boundary conditions for the
Tunguska event is:
melts at h ~ h0, e~(h  h0 )  e m
 11 km/s < vi < 70 km/s
 MSB ~ 108 – 109 kg
 MSB
Solving,
 v 
e 

 10km / s 
2
3



 f  0.5  100m  M A'  1g / cm  0.1eV 

 





0
.
1
cos

R
18
M

e
 


P 
SB
 m 
Some consistent possibilities
that can explain the Tunguska
event
1.An Icy MSB of v ~ 12 km/s, with
R~40m
2.A MSB of rocky material with R ~
20m, v ~ 40 km/s
These could also melt before hitting
the ground, vaposises and explode
in the air at h ~ 8 km
How to detect the presence
of mirror matter?
Pure mirror matter fragment should be
transparent, but if stained by
ordinary dust on the surface, we can
still see and touch it (but may be
dangerous… )
 Pure mirror substance: chemically
inert but still has mass – the
presence of invisible gravitating
matter in a mass spectroscopy
 May form exotic Fe-Fe’, Fe-Pb’ states
nuclei – anomalously heavy elements,
show up in mass spectrometer

Anomalous thermal effect
most feasible way to search mirror
matter (of macroscopic size)
 Mirror matter sucks heat from the
surrounding ordinary matter and
radiate it away into invisible mirror
photons
 Effectively cools the surrounding
ordinary matter
 leave ‘cold spots’ imprint on the
temperature profile of the
surrounding ordinary matter

How to detect this effect?
 Use
infra-red detectors or
infra-red to detect them
 Infra-red
satellites for
Tunguska?
 Think
of your own way
Picture from Jordan impact site
Picture from Jordan impact site
Picture from
Jordan impact
site
View from Kirensk, two seconds before the
explosion.
Painting copyright William K. Hartmann
View from Vanavara trading post, at the
moment of the explosion.
A few minutes after the explosion
Felled trees due to the TSB blast
wave
Portion of one of the photos from
Kulik's aerial photographic survey
(1938) of the Tunguska region
Tunguska 'crater'
 Mirror
matter theory is not
counting how many angles can dance
on the tip of a needle (i.%e. not
fairy tale)
 Their existence has very clear
(though exotic) signatures which
could be experimentally search for
 Life (and physics) would be much
more interesting if there are
mirror matter around
“ Neutrino puzzle”

Solar neutrinos (From SNO)
n e  n  , (  m , ), m  10 eV
-4
2
2
tan 2 solar  0.4 (l arg e mixing)
2

LSND
n m  n e , m 2  0.2 - 10eV2
sin 2 LSND  (1.5 - 40) 10 (small mixing)
2

-3
Atmospheric neutrinos (SuperKamiokande)
2
-2
-3
2
n m  n  orn s , m  10 - 10 eV ,
sin 2  atm  0.85 (maximalmixing)

3 different magnitudes of m2 from three
classes of neutrino oscillation experiments:
 m
i
i atm , solar , LSND
0
if there are only 3 active neutrino states,
 at least one sterile neutrino must exist
 hint for mirror neutrinos
 Is atmospheric neutrino anomaly due to
active-active or active sterile oscillations?
 active-active favored but active-sterile is
only disfavoured at 1.5

Neutrino oscillations
 If
neutrino has mass, the flavour
eigenstates (n, n’) in general does
not coincide with the mass eigenstates
(n, n-
P(n  n’) = sin22 sin2(L/L’osc)
In EPM, mirror-ordinary mixing due
to non-zero neutrino masses is
given by
Lmass = n L
c

m
m
'
 n L  
c 
  H .c.

(n ' R ) 
 

m
'
m
n
'

 R 

m’ is generated by Lint
m  is generated by Lsee-saw
or something else, not in
minimal EPM

The flavour eigenstates (nL, n’R)c) are always
maximally mixed combinations of the mass
eigenstates
nL  12 n n-L
n’R)c  12 n- n-L
No matter how small m’ is.
 maximal mixing is a theoretical
prediction by EPM, i.e. sin22  1
However, maximal mixing is not
always seen in experiments. . .
is a free parameter in
L'osc = 4 E/m the theory
 Some other competing oscillation mode may be
operative [e.g. see-saw, T.L. Yoon and R. Foot,
Phys. Lett. B491, 291 (2000) ] which give large
ne  n oscillations with a characteristic
Losc(ne n)
 If we are in the“ accidental ” parameter
range such that
L’osc(ne  n’e) >> L (Sun - Earth) >> Losc(ne n)
for solar E and L, we would not see maximal
active-sterile mixing

2

Current experimental situation
is stringently testing the EPM!
EPM does not predict bi-maximal mixings
 unless accident occurs twice, i.e.
1) L’osc(ne  n’e) >> L (Sun - Earth) >>Losc(nen)
at Esolar  MeV
and
2). L’osc(nm  n’m) >> L (Earth) >> Losc(nm n)
at Eatm  GeV
 not anticipated by the elegance of EPM


Exciting news for mirror
matter enthusiasts !!!
EPM predicts a unique solution scheme for current
experimental situation:
SNO sees large nmn oscillations solves solar
neutrino problem (to be checked by KamLAND,
BOREXINO)
EPM says:
 atmospheric neutrino anomaly must be solved by
maximal nmns oscillations, i.e. maximal nmns
oscillations must be seen by MINOS, Superbeam,
ICARUS.
 LSND : small mixing nmne oscillations
(must be seen by MiniBooNE)
The prediction of EPM in the
neutrino sector is experimentally
verifiable and falsifiable – the
result to be known soon.
Let’s wait and see.
If Our Universe = SM + SM’, 
parity symmetric
LR symmetric
SM
SM’
LR symmetric
Parity is broken
Only L –handed
Only R –handed
If Our Universe = SM + SM’, 
parity symmetric
LR symmetric
SM
SM’
LR symmetric
Mirror SB interact with air molecules via
Rutherford scattering (an exotic channel
not possible for ordinary SB)
Low altitude OSB (small-size)
must have had a large highly
luminous parent body. So…
if you see a small-size low
altitude fireball (of extraplanet origin) which does not
initially appear higher up in
the sky, your are witnessing
an extraordinary event.
Because of Rutherford scattering,


MSB plummeting into
atmosphere is visible and have
physical impact
But with weird behavior not
explainable by the physics of
ordinary matter !!!
two limiting cases:
(if SB remains intact)
R > 5-10m, v ~ constant
R < 5-10m, loss its
astrophysical velocity
(get ‘stopped’ by air
resistance)
Based on our knowledge on
the behaviour of the MSB,
we want to know if . . .
there is any consistent set of
parameters in which a small MSB
can can survive and hit the ground
without melting, yet glowing at
low-altitude? (not possible for
OSB)
 This is calculable in the EPM
 The answer is …

From the table:
 Small
MSB can reach surface
without melting if
 f ~ < 0.02 for ice MSB
 f ~ < 0.1 for typical nonvolatile materials
 f less than 0.02 is unlikely
(from falling skylabs and
satellites)
Earth’s surface
Mirror
matter
sphere
embedded
in
ground
T
T’ surface temperature
of the mirror body
T
T’< T(R)
R’
R’
Thermal
conductivity
between mirror
matter and
surrounding matter
is non-trivial
 T' 
T ( R)  

 270K 
4
 R' 


 5cm 
2
 50cm 

K
 R 
•
If thermal conduction between
mirror matter and the surrounding
ordinary matter is perfect, T(R) =
T’;
•
Boundary condition: thermal
conductivity must go to zero as
e 0,
•
Therefore, thermal conductivity
cannot be perfect, so T’ < T(R)
Historic precedence:
Lorentz invariance  antiparticles 
 Exact parity symmetry  mirror particles?

EPM Gauge group

GSM  G’SM =
[SU(3)c SU(2)L U(1)Y] 
[SU(3)c’SU(2) L’U(1) Y’]
 LEPM = LSM
+ L’SM + Lint
 LEPM symmetric under parity exchange :
LSM  L’SM
Nature’s
unbroken
mirror?
us, the ordinary
ones
Our mirror
partners
astrophysical hints







Dark matter
MACHO
Close-in solar planets
Isolated planets
Gamma ray bursts
Drag force on spacecraft Pioneer 10, 11
Missing comets, Halley’s and LevyShoemaker comets
Experimental/observational
hints
 Anomalously
shorter lifetime of
orthopositronium (spin 1 bound state) in
vacuum experiments [seen at 5] – due
to photo-mirror photon kinetic mixing
 Maximal active-sterile neutrino
oscillations in atmospheric neutrinos
 And . . . mirror space bodies
bombardment on Earth (main topic of
this talk)
First, consider a small
sized SB with R < 5 - 10 m
 SB’s
velocity drops exponentially

At low altitude v should drop to ~ 0.3
km/s (at terminal velocity ) and cannot
ablate anymore (dark-flight)

Ordinary space body (OSB) ablates
significantly only at high altitude
while vi has not completely lost

So OSB should significantly brighter in
the upper than the lower atmosphere
The area and
orientation
of the
fallen trees

A plummeting MSB is immersed in a
capsule of co-moving air which
will get heated up

Ionisation interactions of both
mirror and ordinary atoms may also
occur

-> a mechanism to render the MSB
visible
They are rare. . .
Expect mirror fragments to exist
right on ground or partly embedded
in the ground on the impact sites
 We don’t find them because they
are scare
 Total area covered by mirror
rocks/fragments integrated over
the last million years is only ~
10 – 100 km2
 The odd to find them on ground is
very rare unless in the impact
sites

 T' 
T ( R)  

 270K 
4
 R' 


 5cm 
2
 50cm 

K
 R 
Sounds like science fiction
huh?
Anyway, let’s explore the
physics and
phenomenological
consequences of these
mirror particles
Does Nature respect exact
parity symmetry?
A WELL KNOWN FACT:
 GSM = SU(3)SU(2)LU(1)Y
 weak interactions is V – A
 parity is broken in in the weak
sector of the SM
Based on theoretical
motivation for
parity should be respected
and unbroken…
Hence,
is proposed to restore exact parity
symmetry
air’s nuclei undergo
Rutherford scattering with
Mirror Nuclei in MSB
Ordinary air
nucleus, Ze
vi
Mirror
nucleus,
eZ’e
11 km/s < vi < 70 km/2
Note: electron screening effect is
weak and can be ignored
Air
molecules penetrate and
thermalise within the MSB via
Rutherford scattering
undergo
many collisions within
the MSB + co-moving air,
effectively dumping most their KE
within the MSB + co-moving air
A
MSB feels atmospheric drag
force roughly the same as if it
were made of ordinary matter
By comparing
(total heat per to
melt the MSB per
mirror atom)
to e m
of some common meteorite and
comet material, we can estimate
what are the physical parameters
of a MSB that causes Tunguska
explosion:
e~SB ( xd )
1)the material (in terms of density,
SB) and chemical composition em.
2)Its initial vi
c.f e m = Q1 + LF; total heat
required to melt the MSB
Q1 = heat required to heat MSB
from 0K -> melting point
LF = heat of fusion (latent
heat) of MSB