Re: Thank Gawd for iMovie and QuickTime

In article <noneof-4A8003.14561004032007@xxxxxxxxxxxxxxxxxxxxxxx>,
Mark Conrad <noneof@xxxxxxxxxxxxxxxxxx> wrote:

In article <timstreater-4C3956.16012904032007@xxxxxxxxxxxxxx>,
Tim Streater <timstreater@xxxxxxxxxxxx> wrote:

"on demand" antimatter fuel could be confined in magnetic "bottles" by
well known superconductivity techniques, until needed at the last
instant inside the reaction chamber.

Neutrons and anti-neutrons cannot be confined
in this way...<clip>...


Correct, that is why I did not say that _all_ antimatter can be
confined in a magnetic bottle, only positrons, electrons, protons, and
anti-protons.

However look at it this way. Ordinary neutrons can be further broken
down into 3 other particles:

1) Proton - which can be used directly in the engine as
one of the "fuel" components

2) Electron - which can be used directly in the engine as
one of the "fuel" components

3) Antineutrino - which because of its low mass can be
discarded, without affecting the
efficiency of the engine much

In fact you don't have any choice with the antineutrino. They will whizz
away and ignore anything you might do to stop them. A block of lead a
light-year o so thick might catch a number of them. So you don't
"discard" it, it discards you.

Effectively, the engine has "used" the original neutron as fuel, casting
almost its entire mass out the exhaust at the speed of light

Sure, separating these "fuel" components onboard the spacecraft will
involve a huge amount of energy, however next-generation portable
reactors somewhat like those used on nuclear submarines should suffice.

<http://www.fnal.gov/pub/inquiring/questions/antineutron.html>

Quote from the above website about the process of breaking down an
ordinary neutron might interest you:

"Let us look at an ordinary neutron. If he is in an atomic nucleus, he
is perfectly stable, and could stay there practically forever. However
if a neutron is outside a nucleus, it becomes very unstable, and within
15 minutes decays into an electron, a proton and an antineutrino!!!"

This is of course rather simplistic. The unbound neutron has a half-life
of 15 minutes or so, meaning that after that time 50% of them will have
decayed. In another 15 mins, 50% or the remainder will have decayed, and
so on.

Let me remind you that mankind already knows how to "crack" an atom's
nucleus, to separate the protons and neutrons inside the nucleus.

The protons and electrons can be siphoned off by electric fields,
leaving a residue of neutrons.

If those neutrons can be somehow kept in their free state for 15
minutes, they should decompose like popcorn as per the guy's quote
above, when the resulting "fuel" of protons and electrons can be
gathered and magnetically bottled.

You are still overlooking the crucial point. When neutrons are generated
inside a reactor, they fly off with some speed. How do you propose to
confine them?

Getting the other parts of the fuel supply is not _too_ much of a
problem, as per the below website: (for positrons)

<http://www.stormingmedia.us/62/6212/A621224.html>

The amounts of antiprotons etc that can be confined using todays's
technology are likely to be >TINY< compared to the required quantities.
.

Relevant Pages

  • Re: Aether is the empty space in which the Universe sits
    ... > strong and the neutrons show some compressibility. ... > to it including transverse waves. ... > for the attraction between protons and electrons. ...
    (sci.physics)
  • Re: The simplest of physics!
    ... experiments on neutrons. ... protons do? ... What we say they do (electrons and protons), ... least within fixed areas around the nucleus. ...
    (sci.physics.relativity)
  • Re: =?iso-8859-1?Q?=B2=B2Na?=
    ... this means 11 protons in the nucleus and 11 electrons ... A nucleus with only 11 ... more complicated than hydrogen will have some neutrons, ... In the case of sodium, Na-23 is the only stable isotope; ...
    (sci.physics)
  • Re: Tom Roberts there seems to be something missing?
    ... Such as if you got excess neutrons, protons or electrons in an atom (or ... atoms, protons, electrons, neutrons gone and replaced with the ...
    (sci.physics.relativity)
  • Re: "kern", "kernel", "nucleus", "core"
    ... >>An atom has both a nucleus (the much smaller, ... > The nucleus gives it most of its mass, but protons don't keep it ... Don't neutrons help keep all nuclei but hydrogen's together? ...
    (alt.usage.english)