I stated that it was Wikipedia to make clear that it was "for what it's
worth". I confess that I was pressed for time. I did subsequently send a
link to an article on the Planck length for the general public from
Fermilab Today:
http://www.fnal.gov/pub/today/archive/archive_2013/today13-11-01_NutshellReadMore.html
. The other links that I sent were from the NYT (2009) about the 2009
paper in Nature, and the abstract of a scientific paper (2014) which
contained a link to a PDF of the 2014 paper itself.
In addition, here's a link to Nature's summary "An intergalactic race in
space and time: A burst of γ-rays lets scientists test quantum theories
of gravity", for the general public, of the 2009 paper:
http://www.nature.com/news/2009/091028/full/news.2009.1044.html .
Here's a link to the 2009 paper itself (requires payment) "A limit on
the variation of the speed of light arising from quantum gravity
effects"
http://www.nature.com/nature/journal/v462/n7271/full/nature08574.html .
Here is the abstract http://adsabs.harvard.edu/abs/2009Natur.462..331A :
A cornerstone of Einstein’s special relativity is Lorentz
invariance—the postulate that all observers measure exactly the same
speed of light in vacuum, independent of photon-energy. While
special relativity assumes that there is no fundamental length-scale
associated with such invariance, there is a fundamental scale (the
Planck scale, l_Planck ~1.62×10^-33 cm or E_Planck = M_Planck c^2
~1.22×10^19 GeV), at which quantum effects are expected to strongly
affect the nature of space-time. There is great interest in the (not
yet validated) idea that Lorentz invariance might break near the
Planck scale. A key test of such violation of Lorentz invariance is
a possible variation of photon speed with energy. Even a tiny
variation in photon speed, when accumulated over cosmological
light-travel times, may be revealed by observing sharp features in
γ-ray burst (GRB) light-curves. Here we report the detection of
emission up to ~31GeV from the distant and short GRB090510. We find
no evidence for the violation of Lorentz invariance, and place a
lower limit of 1.2E_Planck on the scale of a linear energy
dependence (or an inverse wavelength dependence), subject to
reasonable assumptions about the emission (equivalently we have an
upper limit of l_Planck /1.2 on the length scale of the effect). Our
results disfavour quantum-gravity theories in which the quantum
nature of space-time on a very small scale linearly alters the speed
of light.
[highlighting added]
Best, Ben
On 12/13/2016 9:29 AM, [email protected] wrote:
If Wikipedia is taken as a scientific authority, then the situation is
really bad.
Kirsti
Jerry LR Chandler kirjoitti 11.12.2016 22:36:
Ben, List:
On Dec 11, 2016, at 1:48 PM, Benjamin Udell <[email protected]>
wrote:
According to Wikipedia, the Planck length is, in principle, within a
factor of 10, the shortest measurable length – and no
theoretically known improvement in measurement instruments could
change that. But some physicists have found that that's not quite as
much of a barrier as it may seem to be.
Your post is unclear. I know of no mathematical nor physical nor
chemical reason for such a conclusion about measurements of
commensurabilities.
Is the mathematics of electric field theory constrained by the
physical principles that motivate this conclusion about this
measurement of Planck’s constant?
Perhaps others may be able to expand on the origin of this conjecture.
But, from my perspective, it is merely another example of the problems
of scientific epistemologies and Wikipedia’s style of informing
public opinion.
Historically, this issue has arise on this list serve with respect
controversial Wikipedia articles that appear to be authored by a
member of Peirce-L.
Cheers
Jerry
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