Re: Upended quantum physics in the news

Glenn wrote:
<carlip-nospam@xxxxxxxxxxxxxxxxxxx> wrote in message
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Glenn <glennsheldon@xxxxxxxxxxxxx> wrote:

http://www.sciencedaily.com/upi/index.php?feed=Science&article=UPI-1-20060215-17171200-bc-us-spintheory.xml

PROVIDENCE, R.I., Feb. 15 (UPI) -- Rhode Island and Alabama
scientists
report creating, for the first time, a "spin triplet" supercurrent
through a ferromagnet over a long distance.

Achieved with a magnet developed at Brown University and the
University of Alabama, the feat upends longstanding theories of
quantum physics. [...]

What a terrible news article. I've read the paper in Nature, and it
has nothing whatsoever to do with "upended quantum physics." It
shows
that a particular phenomenon which has been difficult to demonstrate
-- superconductivity in a ferromagnet -- can be achieved with a
clever
enough choice of materials. This says nothing about the
fundamentals
of quantum physics; the theories of superconductivity and
ferromagnetism
involve quantum physics, but so does everything else in solid state/
condensed matter physics. In fact, as the actual paper in Nature
says,
the coexistence of superconductivity and ferromagnetism had already
been observed (in iron under pressure), and behavior much like what
the paper reported had been predicted from theory several years
before.

Here's the editor's summary of the article, which appeared in Nature
439,
825-827 (16 February 2006):

Under most conditions, conventional superconductivity and
ferromagnetism are mutually exclusive. Although they have
been observed together in iron under pressure, the principle
holds as a rule. But now Keizer et al. describe a system in
which superconductivity and magnetism are finally seen working
together. The material in which this occurs is chromium dioxide,
well known as the active component of magnetic recording tape.
It's a half-metallic ferromagnet, and can sustain a Josephson
(or 'spin triplet') supercurrent that switches with the
direction
of magnetization.

You like to use undefined concepts such as "most" and "conventional"
to denounce concepts like "upend". That'll show 'em.
The article appears to have been written after an interview with a
physicist, assumedly that took part in the research. Now that's not to
say that the article author did not include his own "terrible" ideas
about quantum physics being "upended", but then again, you haven't
shown that the research doesn't.

Here's something I just pulled out of my hat, off the internet:

http://www.cmp.liv.ac.uk/research_magnetism.php
"Theory predicts either an antiferromagnetic structure in the Mn with
moments in the same direction as the ferromagnetic Fe, or a helical
structure. The data show that this simple picture is wrong and that
the moments in the Mn are perpendicular to those of Fe, see Fig. 4."

"Attempts to explain the mechanism of high-temperature superconductors
have shown our understanding of the underlying quantum theory to be
inadequate."

(*The sound of clinking hammers and machinery hums in the background as
physicists scramble to reconstruct the universe as we know it*)

Glenn, I like an occasional romp in the dusty attic of my brain where
high school physics knowledge and a vague memory of some circles being
drawn on a chalk board once presided. Gives me a chance to rummage
through my brain and pick out the junk for my afterlife garage sale...
"Box of useless knowledge, $1". But what does this have to do with
origins?

Mind you, I'm not asking because I hate off topic posts. I honestly
couldn't care less about that. I ask because I've read your other
posts and I know exactly where you stand on evolution and I'm led to
believe that this post ties into intelligent design in some backwards
way.

Care to enlighten us, or am I just paranoid? Maybe I twinged a nerve
when I was groping for the light switch up there.

.

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