The Large Hadron Collider (LHC):
Why we are still at risk
Author:
Anomymous
Editors: J.
Jones and R.D. Jones
October
2008
Summary:
The LHC has been switched on and Earth has
not been destroyed.
Does that mean that there is no danger?
The first switch-on on 10
September was only a test and we must not be misled into thinking that this
unremarkable start-up proved that we are not at risk.
The first LHC collisions will now commence in Spring 2009, although the
full power of the collider will not be used to begin with. However, as the
months pass the power and thus the energy of particle collisions will be
increased. This and the long duration of these experiments will boost the
statistical risk of producing dangerous particles or other unknown and
unexpected effects.
There will always be a risk as long as we
experiment using the technique of opposite speed collisions.
The main defence by CERN is that cosmic rays with
high energy have beeen colliding with Earth for millions of years and yet Earth
is still here.
The failing of this argument is that:
Although heavy particles with little reactivity that are created by cosmic
rays will retain great speed and so will pass through the Earth and be loosed
into space, the same particles created by opposite speed collisions will have a
very low speed and could be captured by Earth’s gravity.
Our study indicates that some categories of
unexpected particles or phenomena present a risk for Earth.
Significant financial and human efforts have been invested in building
the LHC and great hopes for new knowledge are now tied in to it.
Various
safety studies have been produced by CERN, with a more complete evaluation in
2008 [Ref.1, Ref.2 and Ref.3]. The possible creation of stable micro black
holes, strangelets, vacuum bubbles and magnetic monopoles has been studied.
Safety studies are important because new phenomena may be expected and if
any of these are dangerous the whole planet could be involved.
The
conclusions of CERN studies are reassuring but an important safety problem
linked to the possibility of unexpected phenomena has not been adequately
treated in these studies.
The CERN studies evaluate the possibility of dangerous phenomena in the context of our current theories,
but these theories are not complete and unexpected phenomena could occur.
We do not have a complete theory of physics (the “Theory of Everything”)
and numerous factors are not understood (dark energy, dark matter, etc.).
I ** No guarantee of safety from
the behaviour of cosmic rays
The
CERN 2008 study advances as the principal argument in favour of safety the fact
that cosmic rays that have been colliding with Earth and stars for millions of
years with energies far more significant than those reached in the LHC.
At
the same time, these studies accept the fact that opposing collisions in the
LHC will produce particles with speeds
far lower than those produced by cosmic rays which means that the cosmic
ray model cannot strictly be applied to the LHC [Ref.1].
Experiments
using the technique of colliding high-energy particles with opposing speeds create conditions on Earth
different from natural collisions due to cosmic rays.
Starting
from this notion of the slow speed of heavy particles produced by colliders, we
will study the possibility of specific dangers from these colliders.
Special relativity indicates that in the case of a
proton-proton collision between a cosmic ray with a speed of 299,999.9 km/sec
and terrestrial matter, a heavy particle of mass 1 TeV created thereby would
have a speed of 299,700 km/sec. If such a particle is not very reactive it will
“always” cross planets or stars and disappear into space.
The Standard Model is
unsatisfactory. Many other theories have been proposed but at this moment in
time we still do not have a complete and final theory of physics.
An enormous part of the matter
composing the Universe (90%), is unknown
to us (dark matter, dark energy).
Maybe it is just a hole in our
theories that could, in the future, be explained by, for example, the MOND
theory, which proposes a change in gravitational equations over large
distances, or perhaps by other theories.
We should reflect on the limits of our
knowledge and admit that, without a complete theory of physics, we cannot
discount the possibility that high energies in colliders may create unexpected heavy particles (or other
unexpected phenomena).
We can be certain that such
particles could present a much higher risk of being captured by the Earth’s
gravity than is the case with particles produced by cosmic rays.
As our theories are incomplete and
the particles are unknown, if such an event was to occur, the significance of
the danger to Earth would be difficult to evaluate.
III **Classification of
potentially dangerous particles:
We suggest studying the possibility of danger with a classification of
particles in relation to their reactivity with terrestrial matter, their time
of decay, the possibility of absorption of other particles etc.. A first
attempt at such a classification is proposed here:
******Classification by
particle effect:
A/ Heavy particles that
can absorb matter (same effect as a black hole as an example)
B/ Heavy particles that
could transform ordinary matter (same as strangelets)
C/ Heavy particles that
could destroy ordinary matter (same as monopoles)
D/ Heavy particles dangerous
for other reasons
*******Classification by
reactivity with ordinary matter.
Such particles could only present danger if the safety cosmic ray model
cannot be used:
A/ In case of little reactivity with ordinary matter.
Danger levels will depend on the rate of decay and on the degree of
reactivity.
In the case of a long decay time, if such particles are created by cosmic
rays they will retain significant speed, pass through the Earth, and become
lost in space.
If they are produced with
opposite speed collisions as in the LHC, some of these particles could present
a serious danger because their slow speed could mean capture by terrestrial
gravitation.
This could be the case with an absorbing particle which is not very
reactive.
B/ Heavy particles reactive only at very slow speeds.
Danger levels here will also depend on the decay time and on the degree
of reactivity.
These particles could present a
danger because of their slow speed, resulting from the use of opposing speed
collisions as in the LHC or RHIC.
This could be the case with particles that transform or absorb at slow
speeds.
C/ Heavy particles that are non reactive with ordinary matter present no
danger.
D / Heavy particles reactive with ordinary matter.
Such particles theoretically do not present any danger because the cosmic
ray model is valid in this case; they would always be captured by terrestrial
matter.
IV **Some examples of possible
danger:
1/ *****A small unexpected phenomenon could have
grave consequences
Recently, the RHIC succeeded in producing a
plasma of quarks-gluons [Ref.5] (the last step before creating black holes with
even higher energies).
The physicists were amazed to see that this plasma was much denser than expected,
acting like a “drop of liquid” and not like a “gas” as predicted by theory.
This quark-gluon plasma reduces the speed of
and retains the particles created in the collision (“particle beam
suppression”) and as this plasma, moreover, also produces
« strange quarks », we can conceive that it could slow their speeds
and create, given prolonged use of the RHIC accelerator, the famous strangelet
considered so dangerous to the planet.
Arguments suggest that in the LHC
the strangelet danger will be less significant than in the RHIC but it is
notable that the LHC will be producing a greater number of these decelerating
plasmas.
In this example, we cannot confirm
absolutely that the decelerating plasmas present a real danger but we want to
point out that simple unexpected phenomena could be the source of significant
danger.
2/ *****Another example linked
to the rapid development of theories:
In the RHIC safety study, [Ref.4] the number of dimensions for evaluation
was only 4.
At that time, they did not imagine that there could be the possibility of
a larger number of dimensions that could facilitate the creation of heavy
particles.
If a larger number of dimensions exist, the creation of black holes could
be easier than predicted and in this case the evaluation of danger by the RHIC
would have been false or incomplete.
The rapid rate of evolution of
theories shows the need for prudence and theories or risk-evaluations could be
obsolete within a few years or even a few months.
3/ ***** Possible mistakes in
evaluation.
In the first CERN safety studies for the LHC, the physicists had not
considered the possibility of non-evaporation of micro black holes and their
possible capture by Earth because Hawking evaporation seemed to be fact. For
similar reasons, any safety study could be revealed to be incomplete or invalid
because of human error.
V ** Risk evaluation:
Risk evaluation for unexpected
phenomena is always subjective and
depends for the evaluation on knowledge that we do not yet have.
Yet risk evaluation is of crucial
importance, because the safety of the entire
Earth is involved.
A reasonable minimum estimate of
unexpected phenomena or the creation of unexpected particles in the LHC could,
as an example, be evaluated as between 1% and 10% and the possibility that they
present a danger could be evaluated between 0,1% to 1%.
Such a risk to the Earth is not
acceptable.
VI ** Conclusion:
We do not have a complete theory of
physics and we must acknowledge that high energies could create unexpected heavy particles (or other
unexpected phenomena).
CERN safety studies evaluate the possibilities of dangerous phenomena in
the context of our current theories, but that does not means that completely
unexpected phenomena could not occur and mean danger for Earth.
This
study seems to indicate that some categories of unexpected particles or
phenomena could present a risk.
Previous accelerators, less powerful, have never yet produced a
catastrophic event and it is easy to imagine that this will always be the case;
but this could be an illusion.
If we accept that the behaviour of cosmic rays can no longer be
considered as a proof of safety for the use of opposing high-energy collisions
we must acknowledge that:
The more powerful the
accelerator becomes, the more unpredicted and dangerous events may occur.
As noted above, a reasonable minimal
estimation of unexpected phenomena or unexpected particles could, as an
example, be from 1% to 10% and the possibility that they present a danger could
be from 0,1% to 1%.
It is suggested that the risk that could be accepted is equivalent to the
exceptional and very small risk of a heavy meteor colliding with the Earth, or
the risk of a close supernova destroying all life on Earth.
Earth is our most precious
treasure and we cannot permit any dangerous risks,
just for the satisfaction of our scientific knowledge.
A 0,1% or a
1% risk for Earth cannot be accepted.
We propose obtaining data safely
from astronomical sources or from accelerators not using opposite speed particle collisions.
As an example the satellite Planck (launch is
scheduled for the end of 2008) or the neutrino detector KATRIN in 2009 could
bring answers about the possible MOND theory.
In addition, the use of particle detectors to
study cosmic rays over many years could give data as significant as that from
colliders.
The
best calculations, the best theories could prove to be wrong when tested.
Since it concerns a risk that could threaten the security of the planet,
the decision taken must transcend all personal interest and if we have the
least doubt, the LHC must not be activated.
As long as we do not have a
satisfactory and complete theory of physics and are ignorant of the composition of 90%
of the matter of the Universe it would
seem wise to defer activation of the LHC
In this current age
when we need to preserve and develop our planet
the ‘precautionary principle’* or ‘safety first principle’ indicates
that we should wait for more precise data coming from Astronomy before
proceeding with any experiments with high energy opposite speed particle
collisions.
* http://en.wikipedia.org/wiki/Precautionary_principle
______________________________________________________________
References:
1.. Review of the
Safety of LHC Collisions. LHC Safety Assessment Group.2008.
John Ellis, Gian Giudice, Michelangelo Mangano, Igor Tkachev(**) and Urs
Wiedemann
2..
CERN-PH-TH/2008-025
Astrophysical implications of hypothetical stable TeV-scale black holes
Steven B. Giddingsa,1 and Michelangelo L. Manganob,2
3..Review of the Safety of LHC Collisions. Addendum on strangelets
LHC Safety
Assessment Group.
4.. Review of speculative disaster scenarios at RHIC
W.Busza, R.L. Jaffe, J.Sandweiss and F.Wilczek
5.. BBC New