FUSION
•Process when light atoms fuse to form
heavier ones. During the fusion of elements
with low atomic numbers, substantial
amounts of energy are released.
•Power source of the sun and stars
• Result of a conversion of matter into
energy.
FUSION
• How does it do that?
• Hydrogen, the LIGHTEST atom, is heated to a VERY
high temperature
• This forms a special gas called plasma
• While in the form of this plasma, hydrogen atoms
combine or fuse to make a heavier atom otherwise known
as helium.
• During the fusing process, some hydrogen is converted
directly into energy.
FUSION
• What’s so important about fusion energy?
• Fusion energy would complement current, renewable
energy technologies.
• The use of fusion energy to power cities wouldn’t add
to the global warming problem and wouldn’t cause air
pollution.
• Available to all nations
• No long-lived radioactive waste.
Environment friendly energy solution!
FUSION
• If fusion energy is so great, why isn’t it
available?
• Temperature at which fusion takes place naturally:
Sun’s temperature = 6000K
6000K = t°C + 273.15
= 5726.85°C
t°F = 1.8(5726.85) + 32 °
t°F = 10340.33°F
• Challenge: to harness and create fusion energy for benefit
of mankind at room temperature.
*drum roll*
COLD FUSION
• Idea:
– The fusion energy process found on the sun could be induced and
produced on a table-top by electrolyzing heavy water molecules
with electrodes of palladium and platinum.
•
•
•
•
Cold fusion is a “pariah” field of science.
Cold fusion papers are almost never published.
Lots of external criticism.
Good idea, but scientifically impossible.
COLD FUSION
• Professor Francesco Scaramuzzi; Frascati, Italy
• Reasoned that electrolysis wasn’t necessary, and it
served only to get deuterium.
– Isotope of hydrogen; 1 neutron and 1 proton to give it a
mass number of 2.
• Also thought that the system would not need to be
in thermodynamic equilibrium.
COLD FUSION
• Arranged to put titanium shavings in a cell pressurized
by deuterium gas.
• Used liquid nitrogen to run the cell temperature up
and down, thus creating the thermodynamic
disequilibria.
• Apparatus was not suitable for the difficult
measurement of heat coming from the alleged fusion
energy process.
• Looked for neutrons, because Jones detected neutrons
in his experiment.
• During this experiment, nothing was detected except
for a few occasions of substantial neutron outbursts.
COLD FUSION
• Project was seemingly successful, deemed
the “little science beats big science”
– Chemists v. physicists.
• Suddenly, Italy had more to offer the world
than sunshine and pasta – dry cold fusion.
• There was still much skepticism, because of
the unlikely probability that the fusion
actually took place.
COLD FUSION
• Why was there doubt?
• Cold fusion violated central canons of scientific
logic.
• Proponents of cold fusion could not yield expected
results from their own experiments.
– Incompetently done
– Lacked a crucial ingredient
• Yet, some scientists refused to believe what they
could not reproduce in their own labs.
COLD FUSION
• What violation?
• Primary event of dry cold fusion had to have been
the fusion of 2 deuterium nuclei.
– Catch: deuterium nuclei repel each other because of the
electric force between them.
– If they get close enough, they could fuse together
because of “strong” nuclear force.
• Quantum mechanics allow deuterium nuclei to
fuse by accident; however, probability is small.
COLD FUSION
• Considering the amount of space between
the 2 deuterium nuclei, the probability of
fusion is too small to produce the claimed
results.
– Inter-nuclear spacing
COLD FUSION
• Theoretical difficulties
– Fusion of 2 deuterium nuclei form nucleus of helium-4
– Too much excess energy
– Causes He-4 to break into 2 smaller pieces
• Loses a neutron, He-3
• Loses a proton, H-3, or tritium.
– One in a million chance that it won’t break apart.
• Emits a powerful gamma ray photon while “zooming” off
– Half of fusions will produce energetic neutrons, and
other half will leave tritium behind.
COLD FUSION
• Neutrons WERE produced by experiments
of Jones, Scaramuzzi
– Not enough to account for the alleged amount
of heat produced.
• Heat would, presumably, be the end-result of energy
carried away by nuclear fragments.
– If enough fusions had taken place to produce
the amount of heat claimed, the flux of neutrons
would have been enough to kill.
COLD FUSION
• Conclusion?
– The fusion that occurs inside a piece of metal
produces a radically different outcome than the
one produced by the fusion that occurs on the
Sun, in hot fusion plasma, an atomic bomb, or a
nuclear accelerator.
COLD FUSION
• Technical conclusion
– Atomic nucleus is too small compared to the distances
between atoms in a metal.
– Events in natural, nuclear fusion occur so quickly, that
the metal is simply incapable to respond.
• 9 orders of magnitude SLOWER than the fusion and break-up
in a rarefied atmosphere.
– Crystal cannot absorb amount of energy released by the
nuclear reaction.
COLD FUSION
References
• U.S. Fusion Energy Sciences Program. 2001. Department
of Energy. 5 Nov. 2002. http://wwwofe.er.doe.gov
• Goodstein, David. “Whatever Happened to Cold Fusion?”
5 April 1994.
http://www.its.caltech.edu/~dg/fusion.html
• Masterton, William L., and Cecile Hurley. Chemistry:
Principles and Reactions. 3rd ed. Pennsylvania:
Saunders College Publishing, 1997