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A Fusion Future?

  1. Apr 10, 2005 #1
    If this is probable:http://news.bbc.co.uk/1/hi/sci/tech/4270297.stm

    then 'Stars in a Jar' would be the ultimate weapon, clean thorough and totally effective.

    Lets say the evidence existed from the LAN 'newmexico' database, and this mysteriously vanished along with other relevant papers detailing experimental setup and such.

    If the process becomes mainstream, and Fusion of this type can be created, the the 'Star' could be made to go Supernova?

    Unlike the fission 'China-Syndrome' catastrophe, a Star that was created with the sole purpose to invoke a Supernova Explosive devise, could theoretically be used to Terrorise any civilization within at least 4 to 5 lightyears from the Product.

    Is this feasable? can a 'Star_in_a_jar' be the Ultimate 'blackmail' weapon?
  2. jcsd
  3. Apr 10, 2005 #2


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    Just because you have fusion, doesn't mean that you have the potential
    for a supernova.

    Our own Sun is undergoing nuclear fusion - but it will not go supernova -
    it is too small. The Sun will end its life with a whimper, not with a bang.

    Dr. Gregory Greenman
  4. Apr 10, 2005 #3
    But why did they control rods (neutron absorbers) in the "college basement" prior to the Manhatten Project?..to produce the reaction or to prevent the reaction from a runaway?
  5. Apr 10, 2005 #4


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    The Manhattan project had nothing to with fusion. It was (as most of you should know) set up to develop fission weapons. Fission reactor development (where neutron absorbers were needed for control) was an essential part of the research effort.
  6. Apr 10, 2005 #5
    ...The latter - to prevent the fission reaction from running away. If the fission reaction had run away, the scientists would have been bombarded with neutrons. A runaway fission reaction is different from a supernova.
  7. Apr 11, 2005 #6
    Which is exactly what I was stating, just like mathman said in previous post, I do know quite a bit about the MP and process involved, but I stated the obvious to run parallel to what I was going to state here:

    The collapse of a Star(supernova) 'IS' a runaway Fusion process! whereas a Star in A Jar is a Controlled fusion reaction?...there would be inevitable consequences, if..and its a big if, certain factors were to occur.

    Without obviouslly stating those factors!

    Thanks for the input.
  8. Apr 11, 2005 #7


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    First - Fermi's experiment was a FISSION reactor - not a fusion reactor.

    Secondly - you have to understand how a fission reactor works. You want
    a fission reactor to be exactly "critical" - that means [ contrary to the
    conventional implication ] that the production rate of neutrons in the
    reactor exactly equals the destruction rate. When production equals
    destruction; the reactor is at steady-state; and the power level is constant.

    In order to do that, you build the reactor with some excess reactivity -
    so that in the absence of the control rods the production would slightly
    exceed destruction. The presence of the control rods which absorb
    neutrons then increases the destruction so that it matches production.

    Unlike a car, where you can step on the throttle and add more fuel to
    make the car go faster - in a nuclear reactor, you add an absorber to
    damp the reaction.

    Contrary to popular misconception - a reactor won't "runaway" if the
    control rods are pulled out. There are numerous other feedbacks that
    come into effect. In the case of Fermi's reactor; as the graphite
    moderator of the reactor heats up, it becomes less dense, and therefore
    moderates neutrons less.

    Fermi's reactor also used natural [ unenriched ] uranium which is 99.3%
    non-fissile U-238. This would also lead to substantial negative feedback
    mechanism due to Doppler broadening of absorption resonances in the

    Dr. Gregory Greenman
    Last edited: Apr 11, 2005
  9. Apr 11, 2005 #8


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    It's NOT "if" - not even a "big if" - it just plain won't happen!!!

    You state "without obviously stating those factors" - why not state
    the factors - if you know them.

    If you won't state the factors - I will - you need a mass of plasma that
    is several times the mass of the Sun in order for the star to go
    supernova. The supernova is the result of an implosion of the star - an
    implosion that is driven by gravity. The massive gravitational force
    of the Sun is not sufficient to drive this implosion - which is why the
    Sun will not turn into a supernova.

    Contrary to your implication above - there's no harm in stating the
    conditions for a supernova - a mass several times that of the Sun -
    because there's no way we can achieve that here on Earth - Hell, the
    Sun, which is a million times more massive than the Earth, can't do it.

    Why don't you educate yourself on the physics of a supernova, courtesy
    of NASA's Goddard Space Flight Center:


    Dr. Gregory Greenman
  10. Apr 11, 2005 #9


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    Only in the case of the rare Type 1a supernova is there a runaway fusion
    reaction. [ You need a binary star system for a Type 1a. ]

    The usual Type II supernova is NOT a runaway fusion process - it a
    runaway GRAVITY process!!

    You get the Type II supernova when the fusion reactions have STOPPED.

    You can only get energy from fusion if you are below Iron on the periodic
    table. Iron is the most stable element. If you can fuse elements lighter
    than Iron; or fission elements heavier than Iron - you release energy.

    Iron is the ultimate nuclear "ash".

    When a star has burned all its fuel to Iron - the fusion reactions stop.
    Without the heat produced by fusion, the star can not resist its own
    gravity which collapses the star.

    The most common Type II supernovae are NOT caused by fusion, - they
    are caused by GRAVITY!!!

    Look under the heading, "What Causes of Star to Blow Up", in the web
    page from Goddard to find, "Gravity gives the supernova its energy."

    Dr. Gregory Greenman
    Last edited: Apr 11, 2005
  11. Apr 11, 2005 #10
    Below is some extracts from:http://nuclearweaponarchive.org/Nwfaq/Nfaq4-3.html
    There are NEW ways of dealing with certain fusion 'imploding' yeilds:
    4.4.5 Fusion Stage Nuclear Physics and Design Fusionable Isotopes

    The important thermonuclear reactions for weapons are given below:
    1. D + T -> He-4 + n + 17.588 MeV (n kinetic energy is 14.070 MeV)
    2. D + D -> He-3 + n + 3.2689 MeV (n kinetic energy is 2.4497 MeV)
    3. D + D -> T + p + 4.0327 MeV
    4. He-3 + D -> He-4 + p + 18.353 MeV

    The first fuel ever considered for a thermonuclear weapon was pure deuterium (reactions 2 and 3, which are equally likely). This is primarily because deuterium is a relatively easy fuel to burn (compared to most other candidates), is comparatively abundant in nature, and is cheap to produce. In fact, no other fuel has this same combination of desirable properties.

    Only one other fusion fuel is easier to ignite - a mixture of deuterium and tritium (reaction 1). At moderate thermonuclear temperatures, the T-D reaction is 100 times faster than D-D combustion. Unfortunately, tritium does not occur in nature in useful amounts, and is very costly to manufacture.

    end of extract.

    current understanding of Parametric Downconversion, with high yeild Bose Einstien Condensate's, points to a Quark-Gluon type Repulsive Reactant device, as being real in the very near future.

    I have done some back of the 'Born' envelope calculations, and I see the prospect of a 'cosmic-devise', which is not like the Fission Reactions you clearly point to?

    Lets give an example, its well known that BEC collapse, produces particle jets, the particle yield is amplified according to the 'size' of the BEC. Now if we use the analogy of the Campus Core/pile used in the Manhatten Project, the 'atomic pile' is similar to the single BEC?

    I have to dissapear for a awhile....

    Ok..lets continue, the nasa site for some simplistic overview:http://imagine.gsfc.nasa.gov/docs/science/know_l2/supernovae.html
    clearly states:What Causes a Star to Blow Up?
    Gravity gives the supernova its energy. For Type II supernovae, mass flows into the core by the continued making of iron from nuclear fusion. Once the core has gained so much mass that it cannot withstand its own weight, the core implodes. This implosion can usually be brought to a halt by neutrons, the only things in nature that can stop such a gravitational collapse. Even neutrons sometimes fail depending on the mass of the star's core. When the collapse is abruptly stopped by the neutrons, matter bounces off the hard iron core, thus turning the implosion into an explosion: ka-BOOM!!!
    For Type Ia supernova, the energy comes from the run-away fusion of carbon and oxygen in the core of the white dwarf.

    butt..according to R LAUGHLIN:http://large.stanford.edu/rbl/articles/p01sep00.htm [Broken]

    the gravity according to 'nasa' can be mimicked by :http://edu.ioffe.ru/register/?doc=galperin/l14pdf4.tex [Broken]

    in fact one reason that Quantum Gravity is puzzling, is because the Gravitational Effects are replaced by Electro-Magnetic 'field' effects down on quantum scales, the strong-force IS gravitational in quantum 2-d scenarios.

    Thus, if one creates a 'metallic-like-pile':http://arxiv.org/abs/cond-mat/0305697

    one can use this to implode in a repulsive action, reproducing(actually increasing the strong-coupling-force, to instigate a 'runway' implosion, with the emmision products being scattered from the edge, a "Bose-nova"...mimicking a Supernova..??

    Question:Are Stars Liquids..Solids..Gas or Plasma?
    Last edited by a moderator: May 2, 2017
  12. Apr 11, 2005 #11
    Man-made supernovas

    Spin Network:

    Most of your above-reply to Morbius was web-plagiarized and/or garbled. You seemed to imply before that you thought that a supernova could be created by human-created nuclear devices on Earth. Morbius seems to have responded to that by explaining why he doesn't think a man-made supernova - at least in the near term - is plausible.

    Were you trying to say in your post above that you still think that man-made supernovas via near-term technology are plausible?
  13. Apr 12, 2005 #12


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    Stars contain massive amounts (1E33-1E36 g) of hydrogen, helium and other light elements, with traces of heavier elements, in the form of plasma. Older stars may have much more in the way of heavier elements.

    The cited paper by R.B.Laughlin,"The Quantum Criticality Conundrum", has to do with materials near absolute zero and particularly correlated-electron materials like yttrium-barium-cuprate (YBCO) superconductors.

    http://www.nist.gov/public_affairs/releases/tn6240.htm [Broken]
    It is unfortunate that the NIST people used an analogy with a pocket-sized supernova. The BEC phenomenon has nothing to do with a star going supernova - the energy densities are orders of magnitude different - much the same a the detonation of 1 kg of TNT is 9 orders of magnitude less energy than a 1 MT thermonuclear warhead. Even a 100 MT thermonuclear warhead does not a supernova make. The only similarity between a chemical explosion and a nuclear explosion is that the energy transforms a solid into a gas 'very quickly' with a concommitant rapid change in volume - that basically explains the term 'explosion'.
    Last edited by a moderator: May 2, 2017
  14. Apr 12, 2005 #13


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    All you've succeeded in doing is to show that you don't understand
    supernovae, nor BEC, nor the Fractional Quantum Hall Effect, nor
    Quantum Gravity...

    You've just put together a bunch of unrelated "mumbo-jumbo".

    I'm at a lost as to how to respond to this potpourri of illogic nonsense.

    Dr. Gregory Greenman
    Last edited by a moderator: May 2, 2017
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