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Article #15436Scale Relativity
From: cyrano
Date: Sun, 14 Feb 1999 00:00
Date: Sun, 14 Feb 1999 00:00
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Warning: these HTML pages have been developped from a first version
achieved by E. Lef�vre. For more detail, refer either to the book
(1993), or to
a more recent (1996) review paper, more generally to the bibliography
published on the subject, or to the author at the following e-mail
address:
Laurent.Nottale@obspm.fr
The author:
This theory is proposed by Laurent Nottale, researcher at observatoire
de
Paris-Meudon. He worked for a long time in parallel on gravitational
lenses,
but is now devoting most of his activity to the development of the
theory of
Scale Relativity (in french: Relativit� d'Echelle) within DAEC
department.
The origin
In this chapter, we first present the origin of the Scale Relativity
(or ScR)
theory: we will briefly evoke the reasons that led to its development.
The fundamental principle of ScR:
It is an extension of Einstein's principle of relativity. It can be
stated as follows:
The laws of nature must be valid in every coordinate systems, whatever
their state of motion and of scale. The results obtained show once
again the
extraordinary efficiency of this principle at constraining the laws of
physics.
The method:
The formalism developed by L. Nottale for ScR is already sufficiently
settled
to be used "as is" to deal with a particular problem in many
situations. The
procedure is outlined in this chapter. The most general version of the
theory is
still under construction.
The new principles and their consequences:
There are plenty of them! Among the most important, one finds:
the resolution becomes an explicit variable (which plays for
scale
transformations the role played by the velocity for motion laws),
intrinsic
to the fractal space-time.
the principle of relativity is extended to scale transformations
(on
resolutions). Equations of physics must be covariant: i.e. they
should
keep their (simplest) form in scale transformations. Scale
covariance is
achieved by the introduction of a scale-covariant derivative,
itself
being an extension of the covariant derivative of general
relativity.
this covariant derivative transforms the classical mechanics into
a
quantum mechanics: Newton's equation of dynamics, once made
scale-covariant by replacing the usual time derivative by the new
covariant one, is integrated in terms of a Schr�dinger equation.
non-differentiable nature of Space-Time continuum, which implies
its
fractal character.
existence of 2 asymptotic, unexceedable and invariant under
dilation scales : lP: Planck length (minimal scale) and L:
cosmological
length (maximal scale), in the frame of new "lorentzian" scale
laws.
natural apparition of structures in some systems because of the
theory
itself: no need to invoke the growth of quantum fluctuations any
more!
Organization in chaotic systems (at very large time scales).
formally quantum-like description of chaotic systems beyond their
predictability horizon (t >>20 t_chaos)
The proofs/experimental and observational
tests
(Summary)
The classification is only indicative since some problems belong to
several
categories. It is however not an arbitrary one because the 3 fields of
microphysics, cosmology and chaotic systems correspond to privileged
fields of application of ScR. Respectively: dx et dt tending towards
zero, dx
tending towards infinity and dt tending towards infinity. These are
the three
frontiers of today's physics: the infinitely small, the infinitely
large and the infinity
of complexity.
Particle physics:
convergence of coupling constants, including the
gravitational
one, at Planck energy scale.
prediction of grand unification and electroweak unification
scales.
prediction of the coupling constants values.
relations between particle masses and charges, allowing the
prediction of the mass of the electron from its charge.
Cosmology:
solution to the problem of horizon/causality without
inflation.
large scale structures of the Universe: fractal dimension of
the
distribution of galaxies.
prediction of the value of the cosmological constant.
solution to the problem of vacuum energy density.
explanation for Dirac's large numbers coincidence and
achievement of Mach's principle.
Chaotic systems / large time scales:
structuring of gravitational systems.
prediction of the distributions of the distances,
eccentricities and
masses of the planets in the Solar System
verification in extra-solar planetary systems (see catalog
of
exoplanets).
quantification of velocity differences in binary galaxies.
other quantification effects: stellar radii, obliquities and
inclinations
in the solar system, giant planet satellites, asteroids
distribution,
binary stars, star formation regions, galactic structures,
local
group of galaxies, compact groups, clusters and
superclusters of
galaxies, large scale structures... As predicted by the
theory, the
structures observed at all scales come under a unique
fundamental constant having the dimension of a velocity.
...
For a more complete list of the results and predictions of the
scale-relativity
theory, see Sec. 9 of the review paper. A html improved version of
this section
can be found here.
Non exhaustive bibliography, author's list
of publication (all subjects), list of
publication of the author and others on
scale relativity
general
pulsars
galaxy pairs
Glossary:
Some definitions of the terms used (links in italic).
Other sites:
Dr. Garnet Ord
Dr. Felix Herrmann
Rapha�l Hermann
Dr. G�rard Schumacher
Portrait gallery:
Some of the precursors: Galileo, Newton, etc.
Developed from an initial version due to Eric Lef�vre. To contact
him
click here ou there
The URL of this page is:
http://www.daec.obspm.fr/users/nottale/ukmenure.htm
Glossary (designed by E.T. Lef�vre)
Gravitational Lenses
Effect in which a visible or invisible mass acts as a lens to
"focalize" the light
coming from a background source. (see bending of light) On the image
above,
arcs are images distorted and demultiplied, by the galaxy cluster, of
more
distant objects.
Bending of light rays
When in classical mecanics one considers light as a material
object
and not only as a wave, one can show that (the trajectories
followed by
a body in the gravity field of a much more massive body do not
depend on its mass) a light ray passing at a distance r of a body
of mass
M undergoes a deviation of angle
.
In general relativity, light follows the curvature of Space-Time
induced by the mass M and undergoes a deviation of angle
.
This effect has been verified by Eddington in 1919 during an
eclipse.
The measurement of the deviation angle predicted by GR
constituted
the first experimental verification of Einstein's theory.
Planck length
Length obtained by combining the fundamental constants
(where h is Planck's constant), c (vacuum speed of light) and G
(gravitation or Newton constant) to obtain a quantity having the
dimension of a length.
This microscopic length constitutes in ScR an unexceedable,
unreachable (it is an asymptot, an horizon) and invariant under
dilation, scale (or resolution). Even if it is only very small,
it has all the
physical properties of an infinitely small!
It is the smallest scale of Nature. The fact that it is not null
has
enormous repercussions on physics, like the finiteness of the
speed of
light.
The Planck mass MP and Planck Energy associated to it, EP = MP
c2, are also computed from the 3 fundamental constants G, h and
c:
MP= (hbar c / G)^(1/2)
Cosmological length
length linked to the cosmological constant by:
Second length invariable under dilation that appears in ScR. It
is the
counterpart of the Planck length at large scale.
Is is the largest scale of Nature
Fractal Curve
Let's consider a continuous but
non-differentiable curve
(function). In general these two limits are even not defined,
i.e. one
cannot define the slope of the curve in any point.
An example of topological dimension 1 is the curve:
5th iteration from the generator
BE CAREFUL!: a (too) common error is to define a fractal curve or
object as an object possessing the property to keep the same
appearance under successive zooms. It applies only to
self-similar
fractals like the preceeding curve!
The word fractal refers, in ScR, to the appearance of a priori
new
structures along successive zooms toward small or large scales,
which
leads to a divergence for resolutions tending towards zero
(towards
Planck's scale in special ScR) and the infinity (cosmological
scale in
SScR).
Space-Time
A physical definition of Space-Time could take an entire book!
However, giving a mathematical definition is relatively more
simple.
In relativity and quantum mechanics, an event involving 1 body is
characterized by 4 and only 4 coordinates (x,y,z,t). One puts
apart
properties like charge, spin, etc. and it does not mean that
knowing
only one (x,y,z,t) is sufficient to determine the evolution of a
system but
that the necessary quantities only depend on x, y, z, and t.
Space-Time constitutes the set of all possible (x,y,z,t)
quadruplets
and their transformations
Relativity's Space-Time is continuous and curved (the case were
it is
flat being not excluded a priori) and differentiable. This kind
of Space
cannot account for the quantum properties of matter.
Quantum Mechanics' Space-Time is in principle flat, minkovskian
and differentiable. The contradiction with relativity as well as
other
considerations leads to attempts at including another kind of
Space-Time in quantum mechanics, that have been up to now
unfruitful..
In Scale Relativity, a criticism of measurement theory in
physics, in
particular of the role played by the resolutions, (c.f. the
importance of
the analysis of how we make measures of length and instant in the
premisses of Einstein's theory) led L. Nottale to give up the
(implicit)
hypothesis of the differentiability of Space-Time, which implies
its
fractal and curved nature. The fractal Space-Time, explicitely
dependent on resolutions, can be reduced to the definition of a
"Space-Time-Zoom" with 5 dimensions (x,y,z,t,D). It is the
fractal
dimension, became a variable, which plays the role of a 5th
dimension
for scale laws (just as relativistic motion laws are implemented
by the
interpretation of time as a 4th dimension).
The concept of fractal space-time has also been independently
introduced by Garnet Ord as a geometric analogue of relativistic
quantum mechanics.
Chaos time
A chaotic system can be characterized by the behaviour of the
separation between 2 of its trajectories. They are in general
solutions of
a system of deterministic differential equations describing the
evolution
of the system. When the system is chaotic, 2 solutions
corresponding to
2 infinitely close initial conditions exponentially diverge one
from
another. One speaks of an extreme sensibility to initial
conditions.
The deviation follows an exponential law:
is called the chaos time of the system. The inverse of the
chaos
time is the Lyapunov exponent. If, having measured as precisely
as
we want (but not enough to distinguish between the 2 initial
conditions)
the system's parameters (initial conditions) at a time t0, we try
to
determine its state after a time interval much greater than , we
realize
that the deviation between the 2 solutions is now so big that one
cannot
say anything on the state in which the system really is: knowing
that
there are, in fact, an infinity of possible initial conditions
between the
two that we have considered, the system can lie in an infinity of
states
very different one from another. One has a sort of predictibility
horizon which, like the one we are familiar with (due to the
roundness
of the Earth), is not absolute: short term prediction (before the
horizon)
remains entirely possible!
Remarks:
At the present time, in "chaos theory", one analyses
the
behaviour of a system whose differential equations,
describing its evolution, are "classical". In such a
frame,
chaotic behaviour (diverging errors / deviations) only
appears when the equations are non-linear. In Scale
Relativity, the situation is very different in that
sense that the fractal nature of space-time induces an
other
type of chaos, that could be called intrinsic, inherent
to
space-time. This has the effect that a behaviour of the
chaotic type appears at large time scale even in an
ultra-simple like one or 2-body problems (test particle
orbiting around a much more massive one or 2 bodies
orbiting around their barycentre). Such a behaviour is
completely incomprehensible in the frame of current
theories.
Of course, if we could measure all the parameters with
an
infinite precision at the same time, the problem would
disappear. Unfortunately, besides the imprecisions of
the
measuring apparatus, we have learned from quantum
mechanics (Heisenberg inequalities) that it is
physically
impossible (I mean that the impossibility does not lie
in the
instruments but in Physics itself) to measure
simultaneously to the desired precision the position
and
the speed of a particle, for instance. In that case,
the
knowledge of the exact position of a particle implies
an
absolute uncertainty on its velocity. However, it is
not
forbidden to measure individually some quantity with an
absolute precision. In Scale Relativity, the Planck
length constitutes an impassable (because it is an
asymptot) lower limit to the resolution with which one
can
measure a position or a length. At this
length/resolution,
the concepts of position and of length become
degenerated: the whole Universe, measured at Planck's
resolution, as well as all it can contain, is of
extension
equal to the Planck length itself!!
To make it short , the chaotic behaviour is unavoidable!
Strangely, order happens in chaos! (attractors, etc.) How
does
this happen? Scale Relativity brings some elements of an
answer
to this question
Covariant derivative
to be continued ...!
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X-Google-Language: ENGLISH,ASCII X-Google-Thread: 1139f8,c50e6796158c8240,start X-Google-Attributes: gid1139f8,public X-Google-Thread: 10b271,c50e6796158c8240,start X-Google-Attributes: gid10b271,public X-Google-Thread: 114713,c50e6796158c8240,start X-Google-Attributes: gid114713,public X-Google-Thread: 10f545,c50e6796158c8240,start X-Google-Attributes: gid10f545,public From: cyrano@pasdepub.com Subject: Scale Relativity Date: 1999/02/14 Message-ID: <36c628ca.2277101@news.twics.com> X-Deja-AN: 444143239 Organization: Twics Co. Ltd., Japan http://www.twics.com Newsgroups: sci.physics,sci.physics.relativity,fj.sci.physics,fr.sci.maths