Dirk said:Mike said:Sam said:Einstein's Relativity and Everyday Life -- Clifford M. Will
http://www.physicscentral.com/writers/writers-00-2.html
________________________________
Einstein's Relativity and Everyday Life
Clifford M. Will
What good is fundamental physics to the person on the street?
This is the perennial question posed to physicists by their non-science
friends, by students in the humanities and social sciences, and by
politicians looking to justify spending tax dollars on basic science.
One of the problems is that it is hard to predict definitely what the
payback of basic physics will be, though few dispute that physics is
somehow "good."
Physicists have become adept at finding good examples of the long-term
benefit of basic physics: the quantum theory of solids leading to
semiconductors and computer chips, nuclear magnetic resonance leading
to MRI imaging, particle accelerators leading to beams for cancer
treatment. But what about Einstein's theories of special and general
relativity? One could hardly imagine a branch of fundamental physics
less likely to have practical consequences. But strangely enough,
relativity plays a key role in a multi-billion dollar growth industry
centered around the Global Positioning System (GPS).
You can find the correction factor by trial-and-error in a trivial way.
GPS clocks are corrected just once before lift-off and that is all.
[snip remaining crap]
Is there another application of GR? Even the cats in the streets are
starting getting tired of this apologetic talk about GPS and such.
By the way, INS (inertial navigation system) worked in 747's long
before GPS and did the job as well.
SR/GR - hahahahahahahahahahahaha - Falsified over ten times
By someone who can't even calculate how many men it takes
to dig a hole?
http://users.telenet.be/vdmoortel/dirk/Physics/Fumbles/BrainHoles.html
Dirk Vdm
[...]No, there is no lack of published research. But
all published research *must* support relativity
in order to get published.
This is complete nonsense.
Here's a simple way to check. In many areas of physics, papers
often first appear as electronic preprints on the "arXiv,"
http://arxiv.org/. In the past *one week*, the following papers
that don't "support relativity" -- that discuss alternatives to
standard general relativity or talk about observations that could
conflict with general relativity -- have appeared.
In gr-qc:
gr-qc/0606012 [abs, ps, pdf, other] :
Title: An Algorithm for Generating Rotating Brans-Dicke Wormhole
Solutions
Authors: Kamal K. Nandi, Yuan-Zhong Zhang
gr-qc/0606008 [abs, ps, pdf, other] :
Title: Modifying the Einstein Equations off the Constraint Hypersuface
Authors: J. David Brown, Lisa L. Lowe
gr-qc/0605152 [abs, ps, pdf, other] :
Title: Understanding Gravity: Some Extra Dimensional Perspectives
Authors: V H Satheesh Kumar, P K Suresh
gr-qc/0605147 [abs, ps, pdf, other] :
Title: Quantum Modified Null Trajectories in Schwarzschild Spacetime
Authors: Avtar Singh Sehra
In hep-ph:
hep-ph/0606051 [abs, ps, pdf, other] :
Title: Noncommutative Inspired Black Holes in Extra Dimensions
Authors: Thomas G. Rizzo
hep-ph/0606048 [abs, ps, pdf, other] :
Title: Methods of approaching decoherence in the flavour sector
due to space-time foam
Authors: N.E. Mavromatos (King's Coll. London), Sarben Sarkar
(King's Coll. London)
hep-ph/0606045 [abs, ps, pdf, other] :
Title: Soft Gluon Resummation Effects in Single Graviton Production
at the CERN Large Hadron Collider in the Randall-Sundrum Model
Authors: Qiang Li, Chong Sheng Li, Li Lin Yang
hep-ph/0605326 [abs, ps, pdf, other] :
Title: Probing Brane-World Scenarios with Vacuum Refraction of Light
Using Gamma-Ray Bursts
Authors: Merab Gogberashvili (Tbilisi, Inst. Phys.), Alexander S.
Sakharov (CERN & Zurich, ETH), Edward K.G. Sarkisyan (CERN &
Manchester U.)
hep-ph/0605325 [abs, ps, pdf, other] :
Title: TASI 2004 Lectures on the Phenomenology of Extra Dimensions
Authors: Graham D. Kribs
In hep-th:
hep-th/0606032 [abs, ps, pdf, other] :
Title: Exponential Potentials and Attractor Solution of Dilatonic
Cosmology
Authors: Wei Fang, H.Q.Lu, Z.G.Huang
hep-th/0606026 [abs, ps, pdf, other] :
Title: Noncommutative $D_3$-brane, Black Holes and Attractor Mechanism
Authors: Supriya Kar, Sumit Majumdar
hep-th/0606019 [abs, ps, pdf, other] :
Title: Transverse Fierz-Pauli symmetry
Authors: E. Alvarez, D. Blas, J. Garriga, E. Verdaguer
hep-th/0606021 [abs, ps, pdf, other] :
Title: Dynamical generation of fuzzy extra dimensions, dimensional
reduction and symmetry breaking
Authors: Paolo Aschieri, Theodoros Grammatikopoulos, Harold Steinacker,
George Zoupanos
hep-th/0606006 [abs, ps, pdf, other] :
Title: Braneworld stars and black holes
Authors: Simon Creek, Ruth Gregory, Panagiota Kanti, Bina Mistry
hep-th/0606005 [abs, ps, pdf, other] :
Title: Rotating Einstein-Maxwell-Dilaton Black Holes in D Dimensions
Authors: Jutta Kunz, Dieter Maison, Francisco Navarro-Lerida, Jan Viebahn
hep-th/0605287 [abs, ps, pdf, other] :
Title: Comment on the first order noncommutative correction to gravity
Authors: Pradip Mukherjee, Anirban Saha
In astro-ph:
astro-ph/0606078 [abs, ps, pdf, other] :
Title: Cosmology and Astrophysical Constraints of Gauss-Bonnet Dark Energy
Authors: Tomi Koivisto, David F. Mota
astro-ph/0606047 [abs, ps, pdf, other] :
Title: Braneworld inflation from an effective field theory after WMAP
three-year data
Authors: M. C. Bento, R. Gonzalez Felipe, N. M. C. Santos
If this isn't good enough to convince you, you can go to Spires
(http://www.slac.stanford.edu/spires/hep/) and look for papers with the
keyword "MOND" ("Modified Newtonian Dynamics") -- 10 papers so far in 2006.
Or papers with keywords "modified gravity" -- 20 so far in 2006. Or
"Pioneer anomaly" -- 6 so far in 2006. Or "tests of gravity" -- 4 so far.
Or "DGP" (one of the currently popular alternatives to GR) -- 5 in 2006.
Or "TeVeS" (another alternative) -- only one so far in 2006, but 4 in 2005.
Or "higher curvature gravity" (another alternative) -- 2 papers so far in
2006. Or "dilaton gravity" (another alternative) -- 5 papers in 2006.
Or "massive gravity" (another alternative) -- only one so far this year,
but 12 last year. Or "generalized gravity" -- 7 papers so far this year.
Or "Lorentz violation" (papers about the possibility of violations of the
basic structure of special relativity) -- 11 papers so far in 2006, and 78
in 2005.
The idea that papers that don't "support GR' are suppressed is paranoid
nonsense.
Steve Carlip
By forgetting about classical physics and the old inverse square law?
Oops.
6378km radius for the earth
26560km radius for the sv's orbit
(/ 26560.0 6378.0) 4.164314832235811 ; ~4x the distance
Since "Force = G * mass1 * mmass2 / (distance ** 2)" we should get
1/16 the gravity at 4x the distance where the gps sv's orbit.
Thank you Steve. As an aid to other initiates, I found I could access[...]No, there is no lack of published research. But
all published research *must* support relativity
in order to get published.
This is complete nonsense.
Here's a simple way to check. In many areas of physics, papers
often first appear as electronic preprints on the "arXiv,"
http://arxiv.org/. In the past *one week*, the following papers
that don't "support relativity" -- that discuss alternatives to
standard general relativity or talk about observations that could
conflict with general relativity -- have appeared.
In gr-qc:
gr-qc/0606012 [abs, ps, pdf, other] :
Title: An Algorithm for Generating Rotating Brans-Dicke Wormhole
Solutions
Authors: Kamal K. Nandi, Yuan-Zhong Zhang
gr-qc/0606008 [abs, ps, pdf, other] :
Title: Modifying the Einstein Equations off the Constraint Hypersuface
Authors: J. David Brown, Lisa L. Lowe
gr-qc/0605152 [abs, ps, pdf, other] :
Title: Understanding Gravity: Some Extra Dimensional Perspectives
Authors: V H Satheesh Kumar, P K Suresh
gr-qc/0605147 [abs, ps, pdf, other] :
Title: Quantum Modified Null Trajectories in Schwarzschild Spacetime
Authors: Avtar Singh Sehra
In hep-ph:
hep-ph/0606051 [abs, ps, pdf, other] :
Title: Noncommutative Inspired Black Holes in Extra Dimensions
Authors: Thomas G. Rizzo
hep-ph/0606048 [abs, ps, pdf, other] :
Title: Methods of approaching decoherence in the flavour sector
due to space-time foam
Authors: N.E. Mavromatos (King's Coll. London), Sarben Sarkar
(King's Coll. London)
hep-ph/0606045 [abs, ps, pdf, other] :
Title: Soft Gluon Resummation Effects in Single Graviton Production
at the CERN Large Hadron Collider in the Randall-Sundrum Model
Authors: Qiang Li, Chong Sheng Li, Li Lin Yang
hep-ph/0605326 [abs, ps, pdf, other] :
Title: Probing Brane-World Scenarios with Vacuum Refraction of Light
Using Gamma-Ray Bursts
Authors: Merab Gogberashvili (Tbilisi, Inst. Phys.), Alexander S.
Sakharov (CERN & Zurich, ETH), Edward K.G. Sarkisyan (CERN &
Manchester U.)
hep-ph/0605325 [abs, ps, pdf, other] :
Title: TASI 2004 Lectures on the Phenomenology of Extra Dimensions
Authors: Graham D. Kribs
In hep-th:
hep-th/0606032 [abs, ps, pdf, other] :
Title: Exponential Potentials and Attractor Solution of Dilatonic
Cosmology
Authors: Wei Fang, H.Q.Lu, Z.G.Huang
hep-th/0606026 [abs, ps, pdf, other] :
Title: Noncommutative $D_3$-brane, Black Holes and Attractor Mechanism
Authors: Supriya Kar, Sumit Majumdar
hep-th/0606019 [abs, ps, pdf, other] :
Title: Transverse Fierz-Pauli symmetry
Authors: E. Alvarez, D. Blas, J. Garriga, E. Verdaguer
hep-th/0606021 [abs, ps, pdf, other] :
Title: Dynamical generation of fuzzy extra dimensions, dimensional
reduction and symmetry breaking
Authors: Paolo Aschieri, Theodoros Grammatikopoulos, Harold Steinacker,
George Zoupanos
hep-th/0606006 [abs, ps, pdf, other] :
Title: Braneworld stars and black holes
Authors: Simon Creek, Ruth Gregory, Panagiota Kanti, Bina Mistry
hep-th/0606005 [abs, ps, pdf, other] :
Title: Rotating Einstein-Maxwell-Dilaton Black Holes in D Dimensions
Authors: Jutta Kunz, Dieter Maison, Francisco Navarro-Lerida, Jan Viebahn
hep-th/0605287 [abs, ps, pdf, other] :
Title: Comment on the first order noncommutative correction to gravity
Authors: Pradip Mukherjee, Anirban Saha
In astro-ph:
astro-ph/0606078 [abs, ps, pdf, other] :
Title: Cosmology and Astrophysical Constraints of Gauss-Bonnet Dark Energy
Authors: Tomi Koivisto, David F. Mota
astro-ph/0606047 [abs, ps, pdf, other] :
Title: Braneworld inflation from an effective field theory after WMAP
three-year data
Authors: M. C. Bento, R. Gonzalez Felipe, N. M. C. Santos
If this isn't good enough to convince you, you can go to Spires
(http://www.slac.stanford.edu/spires/hep/) and look for papers with the
keyword "MOND" ("Modified Newtonian Dynamics") -- 10 papers so far in 2006.
Or papers with keywords "modified gravity" -- 20 so far in 2006. Or
"Pioneer anomaly" -- 6 so far in 2006. Or "tests of gravity" -- 4 so far.
Or "DGP" (one of the currently popular alternatives to GR) -- 5 in 2006.
Or "TeVeS" (another alternative) -- only one so far in 2006, but 4 in 2005.
Or "higher curvature gravity" (another alternative) -- 2 papers so far in
2006. Or "dilaton gravity" (another alternative) -- 5 papers in 2006.
Or "massive gravity" (another alternative) -- only one so far this year,
but 12 last year. Or "generalized gravity" -- 7 papers so far this year.
Or "Lorentz violation" (papers about the possibility of violations of the
basic structure of special relativity) -- 11 papers so far in 2006, and 78
in 2005.
The idea that papers that don't "support GR' are suppressed is paranoid
nonsense.
Steve Carlip
As I mention in my book, I once tried to post an article "The vacuum-a
proposed blueprint" and was told that "it was too far from the level
of current research in the field to be appropriate for Physical Review
D". You can see it as the permittivity paper #1 on my website in
which I derive the properties of the "quantum vacuum" from scratch.
John Polasek
http://www.dualspace.net
In sci.physics Jerry said:[...][...]No, there is no lack of published research. But
all published research *must* support relativity
in order to get published.
This is complete nonsense.
Here's a simple way to check. In many areas of physics, papers
often first appear as electronic preprints on the "arXiv,"
http://arxiv.org/. In the past *one week*, the following papers
that don't "support relativity" -- that discuss alternatives to
standard general relativity or talk about observations that could
conflict with general relativity -- have appeared.
Cool! I'll be reprinting this on my web site, unless you object.
http://imaginary_nematode.home.comcast.net
John C. Polasek wrote:
You are totally nuts, your so-called "theory contains only a sea of
formulas thrown together with no derivation whatsoever. I got so far as
the "Reason for the failure of the Michelson - Morley experiment". You
need to seek medical help (psychiatric, to be exact).
You read the wrong paper, the gravity one. You can't count. I said
paper #1 and you read #2. But you did get to Fig. 7. Did you skim over
"the cause of gravity" on page 1?
The reason for the nullity of the MM experiment is exactly as I showed
in the diagram, and it's the same as in relativity using (ict x y z)
except everyone seems too dull to notice:
Upstream it's ic + v
Dnstream it's ic - v
c and v are always at right angles and the hypotenuse of such a sum is
the same either way. Therefore, no fringes.
I have already pointed out that the reason for having this inane
metric tensor with -1 1 1 1 is to disguise ict into just another
dimension, ct. And it is a big lie. Time can't be mixed with x y z,
and lot of people are starting to take notice.
Everyone is so ga-ga about the metric tensor that they haven't taken
the time to notice that it isn't a tensor at all. It's an arranged
matrix. It cannot tolerate a similarity transform.
Or maybe you can explain it to me.
John Polasek
http://www.dualspace.net
dda1 said:Fun to watch: two kooks talking nonsense.
Sam Wormley said:Einstein's Relativity and Everyday Life -- Clifford M. Will
http://www.physicscentral.com/writers/writers-00-2.html
________________________________
Einstein's Relativity and Everyday Life
Clifford M. Will
What good is fundamental physics to the person on the street?
This is the perennial question posed to physicists by their non-science
friends, by students in the humanities and social sciences, and by
politicians looking to justify spending tax dollars on basic science.
One of the problems is that it is hard to predict definitely what the
payback of basic physics will be, though few dispute that physics is
somehow "good."
Physicists have become adept at finding good examples of the long-term
benefit of basic physics: the quantum theory of solids leading to
semiconductors and computer chips, nuclear magnetic resonance leading
to MRI imaging, particle accelerators leading to beams for cancer
treatment. But what about Einstein's theories of special and general
relativity? One could hardly imagine a branch of fundamental physics
less likely to have practical consequences. But strangely enough,
relativity plays a key role in a multi-billion dollar growth industry
centered around the Global Positioning System (GPS).
When Einstein finalized his theory of gravity and curved spacetime in
November 1915, ending a quest which he began with his 1905 special
relativity, he had little concern for practical or observable
consequences. He was unimpressed when measurements of the bending of
starlight in 1919 confirmed his theory. Even today, general relativity
plays its main role in the astronomical domain, with its black holes,
gravity waves and cosmic big bangs, or in the domain of the
ultra-small, where theorists look to unify general relativity with the
other interactions, using exotic concepts such as strings and branes.
But GPS is an exception. Built at a cost of over $10 billion mainly for
military navigation, GPS has rapidly transformed itself into a thriving
commercial industry. The system is based on an array of 24 satellites
orbiting the earth, each carrying a precise atomic clock. Using a
hand-held GPS receiver which detects radio emissions from any of the
satellites which happen to be overhead, users of even moderately priced
devices can determine latitude, longitude and altitude to an accuracy
which can currently reach 15 meters, and local time to 50 billionths of
a second. Apart from the obvious military uses, GPS is finding
applications in airplane navigation, oil exploration, wilderness
recreation, bridge construction, sailing, and interstate trucking, to
name just a few. Even Hollywood has met GPS, recently pitting James
Bond in "Tomorrow Never Dies" against an evil genius who was inserting
deliberate errors into the GPS system and sending British ships into
harm's way.
But in a relativistic world, things are not simple. The satellite
clocks are moving at 14,000 km/hr in orbits that circle the Earth twice
per day, much faster than clocks on the surface of the Earth, and
Einstein's theory of special relativity says that rapidly moving clocks
tick more slowly, by about seven microseconds (millionths of a second)
per day.
Also, the orbiting clocks are 20,000 km above the Earth, and experience
gravity that is four times weaker than that on the ground. Einstein's
general relativity theory says that gravity curves space and time,
resulting in a tendency for the orbiting clocks to tick slightly
faster, by about 45 microseconds per day. The net result is that time
on a GPS satellite clock advances faster than a clock on the ground by
about 38 microseconds per day.
To determine its location, the GPS receiver uses the time at which each
signal from a satellite was emitted, as determined by the on-board
atomic clock and encoded into the signal, together the with speed of
light, to calculate the distance between itself and the satellites it
communicated with. The orbit of each satellite is known accurately.
Given enough satellites, it is a simple problem in Euclidean geometry
to compute the receiver's precise location, both in space and time. To
achieve a navigation accuracy of 15 meters, time throughout the GPS
system must be known to an accuracy of 50 nanoseconds, which simply
corresponds to the time required for light to travel 15 meters.
But at 38 microseconds per day, the relativistic offset in the rates of
the satellite clocks is so large that, if left uncompensated, it would
cause navigational errors that accumulate faster than 10 km per day!
GPS accounts for relativity by electronically adjusting the rates of
the satellite clocks, and by building mathematical corrections into the
computer chips which solve for the user's location. Without the proper
application of relativity, GPS would fail in its navigational functions
within about 2 minutes.
So the next time your plane approaches an airport in bad weather, and
you just happen to be wondering "what good is basic physics?", think
about Einstein and the GPS tracker in the cockpit, helping the pilots
guide you to a safe landing.
________________________________
Clifford M. Will is Professor and Chair of Physics at Washington
University in St. Louis, and is the author of Was Einstein Right? In
1986 he chaired a study for the Air Force to find out if they were
handling relativity properly in GPS. They were.
Tom said:Rational, intelligent, inventive, practical folks know
that it does not take 13 hacks of General Relativity to account for the
"38 microseconds per day, the XXXXXX offset in the rates of
the satellite clocks", when a simple equation discovered
by Galileo does the job better.
Tom said:"dda1" raises a good point when he talks about:
"kooks talking nonsense."
Here we are, 100 years after General Relativity
and it continues to generate more hype and heat
than light and advances.
General Relativity is a Tower of Babel
that wastes time, money and minds on such
pursuits as time travel, worm holes, gravity waves, etc.
As thousands of "kooks" have been brainwashed by the Einstein lobby,
and are constantly talking nonsense,
it is an enormous waste of time, money and minds.
A mind is a terrible thing to waste.
--
Bhanwara said:Sam Wormley wrote:
And apparently a master and skilled BS'er too.
1) GPS corrections do not actually use the relativistic computations,
they just re-synchronize. GR says "you have a mismatch,
re-synchronize",
as would have any another system which would have computed
the time required for light to travel the distance.
2) There is indeed a difference between GR, and any non-GR system
used to compute the time required for light to travel the distance.
But this difference is much smaller than the 38 microseconds,
and cannot be discovered at this scale.
Basically, instead of using GR, one could have divided the
distance by the speed of light to arrive at the time difference.
That works, too.
Bob Cain said:"Things should be described as simply as possible, but no simpler."
A. Einstein
Tom said:Rational, intelligent, inventive, practical folks know
that it does not take 13 hacks of General Relativity to account for the
"38 microseconds per day, the XXXXXX offset in the rates of
the satellite clocks", when a simple equation discovered
by Galileo does the job better.
Tom Potter said:Here we are, 100 years after General Relativity
and it continues to generate more hype and heat
than light and advances.
General Relativity is a Tower of Babel
that wastes time, money and minds on such
pursuits as time travel, worm holes, gravity waves, etc.
As thousands of "kooks" have been brainwashed by the Einstein lobby,
and are constantly talking nonsense,
it is an enormous waste of time, money and minds.
A mind is a terrible thing to waste.
Tim said:Huh? Has relativity suddenly become controversial?
Still, our lab attracts quantum-mechanics nutters
from time to time, so I suppose it's only logical
that there should be relativity nutters too. Are
there any Boyles Law loonies or Snell's Law weirdos
out there too?
Phineas said:Yep - stop wasting yours in k00kscreed.
It is interesting to see that Tim
is ignorant of the fact that a simple law
discovered by Galileo over 200 years ago,
( f = f0 * ( 1 + 1/2 * g * distance / C^2) )
does a better job of accounting for the offset
in the GPS satellites, than the 13 hacks of GTR
used by some people on the taxpayer dole.
And as can be seen by Phineas T Puddleduck post,
which tries to make the messenger the issue:
"A wasted mind is a terrible thing."