figures.. I searched his site for the info, and when I saw the first half of that page I skipped the rest... Typhoid Mary, FoodSafety.gov...really. Live and learn I guess.
He should move that link and talk about it. The easy immediate difference good seasonings make (over McCormick) is much more important to good cooking than Word-of-the-Day.com
Alton,
about a year and a half ago at the suggestion of a friend's gourmet cook mother, I bit the bullet and made the upgrade from grocery store McCormick type spices and dried herbs to those carried by Penzeys Spices.
There has been an amazing improvement in everything I cook. Everything from McCormick really is bland dust next to its Penzeys equivalent. (No, I have no affiliation of any sort with Penzeys, just a recent convert).
So where do you go for your dried herbs and spices? Better yet, where do you recommend your viewers & readers buy reasonably priced quality herbs and spices?
We hear a lot about processing power, the number of "neurons" in a neural net, the Turing test, etc, but not so much about the actual nature of intelligence and self-awareness. That said, how much do Strange Loops and complex self-referenciality a la Hofstadter's "Godel, Escher, Bach: An Eternal Golden Braid" factor into current AI theories and practice? Is the 20+ year-old thinking in this book still relevant? If not, what has changed about our understanding of the nature of intelligence and self-awareness?
1/10th of a percent success means failure just about everywhere but spam. 1/10th of a percent of 1 million is still 1000. Would even seem 1/100th of a percent success is still success in the spam world. That's 100 customers for a few bucks in adverstising. Basically you can't lose.
Until that changes spam will just get worse and worse.
Do you think CGI can too often be seen as a "suppressor" of other art forms? The specific example in my head right now is Old Puppet Yoda vs. New CGI Yoda, we haven't seen (AFAIK) any major puppeteering work in cinema in a long time. Other possibly "suppressed" art forms might be makeup art, the art of the stunt man, set construction, backdrop painting, cinematograghy, heck even acting could be listed here. Will CGI be escorting some or all of these art forms down the same path as Silent Films, blacksmithing, and totem-pole carving?
Do you ever want to say "Hey this would be a lot better if it were done with [not CGI] instead"?
A Lost Art Form
on
High Score
·
· Score: 3, Interesting
They don't make "primitive" pinball games anymore. "Primitive" meaning those astounding engineering marvels that look like giant Swiss watch conglomerations inside. Each game being an utterly unique piece of engineering art, with its "software" made out of gears and switches. "Primal" is a significantly better description, and in that sense, I think games have lost a lot since those days. You can feel a pinball game for real, it's not haptic, it's a hunk of metal that you can push and pound and "tilt". Keeping an eye on the butt end of a pinball player, watching him/her play shows that they move most of their entire body. It looks more interactive than Quake because from a physical reality standpoint it is more interactive. Modern games are incredible in their own right, but with primal pinball it is 100% reality, there is no abstraction. Something amazing will be lost forever when the last Midway mechanical pinball machine plays its last ball.
I live within half a day drive of about 11 (quick count) major rivers that were devastated to that point. 6/22/02 was the 33rd anniversary of the Cuyahoga River catching on fire. The river burned like it was gasoline. I'd call that a dead river. Luckily a 33 year combination of declining industry and major watershed restoration efforts has restored it at least to a habitable shadow of its former self. Unfortunately major increases in population, energy production, and heavy commercial livestock production are gradually hammering the Cuyahoga and many other fragile watersheds back to their industrial state, albeit with a different concoction of toxins.
Food may be cheap now, but there has to be a balance in the world between farming and biodiversity. You can't turn the whole world into a farm, nor even half of it, with no fresh water for anyone but humans with filters. It's just not sustainable. (FYI 'sustainable' doesn't mean we can feed all the people, 'sustainable' means trees and bugs and beavers and bunny rabbits and little soil mites are necessary for our survival.)
Water isn't just for drinking silly. Without adequate fresh water we get dead rivers, acid rain, poisoned soil, desiccated ecosystems, and across-the-board rising prices in agro-products.
Drinking water is only a small percentage of what is needed for a healthy water table.
"All the crowing" is the reason the acid rain has been reduced from terrible to fair. One example: The Army Corp of Engineers has placed thousands of lye (alkaline) deposits in thousands of headwaters to reduce stream acidity, which affects the entire hydrological cycle, and thus food production and your last fishing trip.
A little cursory research would prevent laughable sentiments such as "Don't worry about fresh water, we can all use filters."
Chicken & Egg... Agreed. The company in the example is an old-old-school engineering company. My advice would be not to work there unless you're about to starve.
But the idea carries through.. he worked at a "medium sized" software company.. so he should follow your sage advice and also apply to companies just like his current company, similar size / similar products, solely because they'll be interested in his spectacularly appropriate experience while giving him "credit" for being hired there in the first place - this because they are already very familiar with his current company and know that they don't hire morons. When he applies to 'small software company with a totally different product/customer base' chances are they'll know very little about his current employer and thus not extend him the benefit of the doubt so to speak.
What you say about small companies seems to make a lot of sense. BUT:
A good friend of mine is an HR recruiter for a big company. He reads hundreds of resumes per day. All he looks at before tossing a resume is where the candidate worked. Not what they did, or what their education was, but where they worked. If they pass that, then he might look at the rest of the resume. This is because he receives so many resumes that he can afford to use other well known HR departments as his initial filter. E.g. - if they worked 5 years at IBM they can't be that bad. But if they worked 5 years Struggling.com he doesn't need to bother taking a chance on them.
Of course this is just one example, YMMV. Though this does show that working for big well known companies can have the same benefits as graduating from a big well known school.
Not Flandern but referencing him. Have digested "entirely refuted and destroyed.txt"
Please critique this if you're still inclined:
...aberration is the change in the effective direction of approach to a moving target necessitated by the propagation delay of any projectile (whether particle, wave, wavicle, or other). We apply that here to two different types of field-generating forces: gravitation and the radiation pressure from sunlight.
If gravity and light originate simultaneously at the same source (e.g., the Sun) and propagate to the same target (e.g., the Earth) at the same speed (e.g.,
c), then aberration will be the same for both. (That is because tan
(aberration) = vorbit/Vpropagation
where vorbit is the transverse orbital speed of the target body and
Vpropagation is the propagation speed of field regeneration. Approximately,
aberrationvorbit/Vpropagation.) Therefore, gravity and light should produce 3-space accelerations in the same direction (or exact opposite direction, if push and pull are reversed), differing only in magnitude by a scaling constant. Specifically, the momentum transferred to or removed from the target to produce the acceleration is some constant
(usually a mass) times
Vpropagation, a vector, in both cases.
The only physical way to break this equality would require postulating some source of the momentum transfer other than, or in addition to, the propagation speed of the field. Such a postulate would seem to constitute new physics, and would appear to be in trouble with the causality principle because radial forces from the source mass are already spoken for. In the absence of any serious such proposal for a new force, and given that gravity and radiation pressure do not produce anti-parallel forces in experiment (4), one of our premises must be violated. The only premise open to question is the equality of propagation speeds of the two types of force. If gravity propagates very much faster than light, all experimental evidence is immediately satisfied.
We see that all relevant characteristics except possibly field propagation speed are common for the two types of force. Therefore their physical propagation behavior ought to be the same if field propagation speed is the same, or different if field propagation speed is different, because there is nothing else relevant that might distinguish the two types of force. Experiments show without ambiguity that the resulting accelerations are applied in different directions, which implies different field propagation speeds.
To clarify, note than an accelerating target is necessarily changing its momentum vector. Momentum is the product of mass times velocity (or energy over
c2 times velocity, if the projectile is massless) for whatever "projectile" carries the force from source to target. The "velocity" in the momentum is the velocity vector of the carrier, whose direction of travel is along the radial from source to target. Because the momentum is necessarily directed along the radial direction, no part of the exchanged momentum could be applied in some other direction. Specifically, if the projectiles are photons and the force is radiation pressure, the target is pushed in the direction of the arriving photons. Whatever is the mechanism of gravity, how could the direction of its pull be other than along the radial to the source mass? The physics and the meanings of words such as "momentum = mass times velocity" dictate only a single possibility for the vector direction of momentum transfers: the radial direction between source mass and target body. And if that is true, the only physical way left to explain the different effective direction of the force is a different propagation speed for a retarded field.
The same remarks apply to electrodynamic forces between charges. If the field propagation speed were lightspeed, we would be forced to interpret the momentum transfers as applied in a different direction from the direction of travel of the momentum carriers because of aberration. That is why, when the details are examined closely, we hear statements such as "virtual 'photons' (the hypothetical carriers of electrodynamic forces, not to be confused with real photons) travel at infinite speeds". So this "lightspeed propagation" assumption is unphysical and unnecessary. One can have the same equations (to the accuracy of observations) and interpret them in a physically consistent way if the momentum carriers travel much faster than light.
Now that we know that Lorentzian relativity is experimentally viable [18] and allows faster-than-light (ftl) propagation in forward time
[19], ftl propagation is no longer forbidden in physics, and ftl force carriers are the most reasonable interpretation of the equations. I expect that no one would ever have thought otherwise if they had not mistakenly believed that ftl propagation was forbidden in physics.
If the field around a charge propagated with lightspeed delays, then Maxwell's equations would be wrong because they neglect transverse aberration, the main manifestation of field propagation delay. The fact that the equations are correct to first order in
v/c tells us that the field propagation speed must be very fast compared to lightspeed, because the neglect of transverse aberration is the logical equivalent of adopting infinite field propagation speed. If Maxwell's equations did work for fields propagating at lightspeed, then they would work for radiation pressure from light fields too, which they do not. If the field has a measurable delay in reshaping itself to register the motion or acceleration of its source, then one would need to add propagation delay into Maxwell's equations (for example, by taking partials with respect to retarded coordinates instead of instantaneous coordinates). The absence of such propagation delay in the equations means that instantaneous propagation of fields is already built in.
Carlip's paper
In the geometric interpretation of GR, gravity is not a "force" and cannot propagate because target body motion simply follows a curved geodesic path through "space-time" without any force acting. Experiment (5) disputes the possibility that this forceless interpretation of gravity could be correct. So does the dependence of the full GR equations of motion for a target body on that body's own mass. Both are failures of the weak equivalence principle - the notion that "gravity is just geometry".
In his paper [15], Carlip recognizes the concept of gravitational force, as in the field interpretation of GR. But he claims that the experiments (1)-(4) are not direct propagation speed measurements for gravity. They are, however, measurements of aberration or
v/V, where the only unknown is the speed of gravity, V. This makes Carlip's point semantic because the "indirectness" of these measures is not significant.
Carlip claims that we have made an implicit assumption that gravitational acceleration is central and has no velocity-dependent terms. If aberration were non-zero, the acceleration would be non-central. However, observations all confirm that it is in fact central to order
v/c; i.e., directed along radials from the source mass. GR implies that gravitational acceleration is target-body-velocity dependent at order
v2/c2, as shown in equations (2) and (4); but velocity-independent to order
v/c. It is also source-mass-velocity dependent in some of the small terms we omitted. However, all these velocity-dependent terms are typically orders of magnitude too small to cancel the aberration term if
V = c. So Carlip's point is again irrelevant to this discussion because no velocity-dependent terms exist at first order in
v.
If one never considers genuine retardation of propagation between source mass and target body, then infinite propagation speed for gravity is being assumed, whether one says so or not.
Carlip considers his key starting point to be his equation (1.8). Its first term, proportional to
ni, represents the transverse aberration. The second term, proportional to
vi, cancels this transverse aberration to first order. Similarly, in the GR part of the paper, the corresponding equation where this cancellation occurs is (2.2). These two formulas are the only places where transverse aberration enters Carlip's discussion. However, the alert reader will see that Carlip is
beginning with a force vector that points closely toward the true, instantaneous position of the source (to first-order in
v), when he should be beginning with a retarded position. In other words, he assumes what he proposes to demonstrate. Obviously, a vector toward the instantaneous source position can be decomposed into an arbitrary pair of component vectors. So it is unremarkable that Carlip decomposes the instantaneous position vector into a retarded position vector plus an update vector for motion during the propagation delay. This merely creates the illusion that he has begun with a retarded position vector, when in fact he has begun with a (nearly) instantaneous position vector formed of two components.
By omitting transverse aberration, Carlip (like many before him) has effectively adopted a field propagation speed
. No physical or observational basis exists for postulating V = c.
Gravity does not propogate at the speed of light. If the sun winks out it takes Jupiter (for example) so many minute to see this. Any EM waves traveling at light speed from the sun take time to "wink-out" so Jupiter remains "ignorant" of the suns disappearance for awhile. Except for gravity. Jupiter knows instantly that it has nothing to orbit (or at minimum 20 billion times faster than it knows there is no more EM energy coming from the sun). If you introduce a delay in the propogation of gravity - slow it down to light speed - the solar system would fall apart. Check it out
The most amazing thing I was taught as a graduate student of celestial
mechanics at Yale in the 1960s was that all gravitational interactions between
bodies in all dynamical systems had to be taken as instantaneous. This seemed
unacceptable on two counts. In the first place, it seemed to be a form of
"action at a distance". Perhaps no one has so elegantly expressed the
objection to such a concept better than Sir Isaac Newton: "That one body
may act upon another at a distance through a vacuum, without the mediation of
any thing else, by and through which their action and force may be conveyed from
one to the other, is to me so great an absurdity, that I believe no man who has
in philosophical matters a competent faculty of thinking, can ever fall into
it." (See Hoffman, 1983.) But mediation requires propagation, and finite
bodies should be incapable of propagate at infinite speeds since that would
require infinite energy. So instantaneous gravity seemed to have an element of
magic to it.
The second objection was that we had all been taught that Einstein's special
relativity (SR), an experimentally well established theory, proved that nothing
could propagate in forward time at a speed greater than that of light in a
vacuum. Indeed, as astronomers we were taught to calculate orbits using
instantaneous forces; then extract the position of some body along its orbit at
a time of interest, and calculate where that position would appear as seen from
Earth by allowing for the finite propagation speed of light from there to here.
It seemed incongruous to allow for the finite speed of light from the body to
the Earth, but to take the effect of Earth's gravity on that same body as
propagating from here to there instantaneously. Yet that was the required
procedure to get the correct answers.
These objections were certainly not new when I raised them. They have been
raised and answered thousands of times in dozens of different ways over the
years since general relativity (GR) was set forth in 1916. Even today in
discussions of gravity in USENET newsgroups on the Internet, the most frequently
asked question and debated topic is "What is the speed of gravity?" It
is only heard less often in the classroom because many teachers and most
textbooks head off the question by hastily assuring students that gravitational
waves propagate at the speed of light, leaving the firm impression, whether
intended or not, that the question of gravity's propagation speed has already
been answered.
Yet, anyone with a computer and orbit computation or numerical integration
software can verify the consequences of introducing a delay into gravitational
interactions. The effect on computed orbits is usually disastrous because
conservation of angular momentum is destroyed. Expressed less technically by Sir
Arthur Eddington, this means: "If the Sun attracts Jupiter towards its
present position S, and Jupiter attracts the Sun towards its present position J,
the two forces are in the same line and balance. But if the Sun attracts Jupiter
toward its previous position S', and Jupiter attracts the Sun towards its
previous position J', when the force of attraction started out to cross the
gulf, then the two forces give a couple. This couple will tend to increase the
angular momentum of the system, and, acting cumulatively, will soon cause an
appreciable change of period, disagreeing with observations if the speed is at
all comparable with that of light." (Eddington, 1920, p.94) See Figure 1.
I.e. - Accidentally cut someone (a Bad Person) off in traffic who then wrote down your plate number?
Ever get bothered by a strange drunk? Your wife ever get bothered by strangers? She ever make anybody angry? She ever run into a friendly stranger who happens to post pictures to upskirt.com? You say you left the house at 8?
Got any cute little girls in your family? Wonder what time her soccer practice ends?
If you can't care about reasonable privacy for yourself you should consider advocating good privacy for the sake of your loved ones.
Best wishes,
Creepy Guy with an Agenda that involves the Atkinson Family. (NO, not really, all of the above has been to illustrate a point only.)
Slashdot Mirror
figures.. I searched his site for the info, and when I saw the first half of that page I skipped the rest... Typhoid Mary, FoodSafety.gov...really. Live and learn I guess.
He should move that link and talk about it. The easy immediate difference good seasonings make (over McCormick) is much more important to good cooking than Word-of-the-Day.com
Alton, about a year and a half ago at the suggestion of a friend's gourmet cook mother, I bit the bullet and made the upgrade from grocery store McCormick type spices and dried herbs to those carried by Penzeys Spices.
There has been an amazing improvement in everything I cook. Everything from McCormick really is bland dust next to its Penzeys equivalent. (No, I have no affiliation of any sort with Penzeys, just a recent convert).
So where do you go for your dried herbs and spices? Better yet, where do you recommend your viewers & readers buy reasonably priced quality herbs and spices?
Thanks!
How many things do you really want to share that don't have a URL? How about in a few years from now?
Send this screen to a friend..
We hear a lot about processing power, the number of "neurons" in a neural net, the Turing test, etc, but not so much about the actual nature of intelligence and self-awareness. That said, how much do Strange Loops and complex self-referenciality a la Hofstadter's "Godel, Escher, Bach: An Eternal Golden Braid" factor into current AI theories and practice? Is the 20+ year-old thinking in this book still relevant? If not, what has changed about our understanding of the nature of intelligence and self-awareness?
Thank you Dr. W.
1/10th of a percent success means failure just about everywhere but spam. 1/10th of a percent of 1 million is still 1000. Would even seem 1/100th of a percent success is still success in the spam world. That's 100 customers for a few bucks in adverstising. Basically you can't lose.
Until that changes spam will just get worse and worse.
Do you think CGI can too often be seen as a "suppressor" of other art forms? The specific example in my head right now is Old Puppet Yoda vs. New CGI Yoda, we haven't seen (AFAIK) any major puppeteering work in cinema in a long time. Other possibly "suppressed" art forms might be makeup art, the art of the stunt man, set construction, backdrop painting, cinematograghy, heck even acting could be listed here. Will CGI be escorting some or all of these art forms down the same path as Silent Films, blacksmithing, and totem-pole carving?
Do you ever want to say "Hey this would be a lot better if it were done with [not CGI] instead"?
I can see it now... con't. on p.44"
"Free with a purchase of a new Dell!: Sony's all-in-one 40x/12x/32x/CDRW//20x/8x/4x/DVDRW//2x/1x/T-VRDRW.
All Your media are belong.. oh screw it
Doesn't the State of Florida has a forms tallying system they're looking to unload?
Up-Up-Down-Down-Left-Right-Left-Right-B-A-B-A
They don't make "primitive" pinball games anymore. "Primitive" meaning those astounding engineering marvels that look like giant Swiss watch conglomerations inside. Each game being an utterly unique piece of engineering art, with its "software" made out of gears and switches. "Primal" is a significantly better description, and in that sense, I think games have lost a lot since those days. You can feel a pinball game for real, it's not haptic, it's a hunk of metal that you can push and pound and "tilt". Keeping an eye on the butt end of a pinball player, watching him/her play shows that they move most of their entire body. It looks more interactive than Quake because from a physical reality standpoint it is more interactive. Modern games are incredible in their own right, but with primal pinball it is 100% reality, there is no abstraction. Something amazing will be lost forever when the last Midway mechanical pinball machine plays its last ball.
Cursory research:
t m
http://www.washtimes.com/metro/20020313-9699394.h
http://www.boquetriver.org/adopthumanimpact.html
http://www.opg.com/envComm/SEDsup2.pdf
http://www.esa.org/carpenter.htm
I live within half a day drive of about 11 (quick count) major rivers that were devastated to that point. 6/22/02 was the 33rd anniversary of the Cuyahoga River catching on fire. The river burned like it was gasoline. I'd call that a dead river. Luckily a 33 year combination of declining industry and major watershed restoration efforts has restored it at least to a habitable shadow of its former self. Unfortunately major increases in population, energy production, and heavy commercial livestock production are gradually hammering the Cuyahoga and many other fragile watersheds back to their industrial state, albeit with a different concoction of toxins.
Food may be cheap now, but there has to be a balance in the world between farming and biodiversity. You can't turn the whole world into a farm, nor even half of it, with no fresh water for anyone but humans with filters. It's just not sustainable. (FYI 'sustainable' doesn't mean we can feed all the people, 'sustainable' means trees and bugs and beavers and bunny rabbits and little soil mites are necessary for our survival.)
Water isn't just for drinking silly. Without adequate fresh water we get dead rivers, acid rain, poisoned soil, desiccated ecosystems, and across-the-board rising prices in agro-products.
Drinking water is only a small percentage of what is needed for a healthy water table.
"All the crowing" is the reason the acid rain has been reduced from terrible to fair. One example: The Army Corp of Engineers has placed thousands of lye (alkaline) deposits in thousands of headwaters to reduce stream acidity, which affects the entire hydrological cycle, and thus food production and your last fishing trip.
A little cursory research would prevent laughable sentiments such as "Don't worry about fresh water, we can all use filters."
We're too comfortable in our lifestyles to make big changes. It's going to take some catastrophic change that impacts the U.S. directly...
We might have to beef up security, and tell the rest of the world they're either with us, or against us.
Chicken & Egg... Agreed. The company in the example is an old-old-school engineering company. My advice would be not to work there unless you're about to starve.
But the idea carries through.. he worked at a "medium sized" software company.. so he should follow your sage advice and also apply to companies just like his current company, similar size / similar products, solely because they'll be interested in his spectacularly appropriate experience while giving him "credit" for being hired there in the first place - this because they are already very familiar with his current company and know that they don't hire morons. When he applies to 'small software company with a totally different product/customer base' chances are they'll know very little about his current employer and thus not extend him the benefit of the doubt so to speak.
What you say about small companies seems to make a lot of sense. BUT:
A good friend of mine is an HR recruiter for a big company. He reads hundreds of resumes per day. All he looks at before tossing a resume is where the candidate worked. Not what they did, or what their education was, but where they worked. If they pass that, then he might look at the rest of the resume. This is because he receives so many resumes that he can afford to use other well known HR departments as his initial filter. E.g. - if they worked 5 years at IBM they can't be that bad. But if they worked 5 years Struggling.com he doesn't need to bother taking a chance on them.
Of course this is just one example, YMMV. Though this does show that working for big well known companies can have the same benefits as graduating from a big well known school.
Yep, just a Freudian Slit.
Please critique this if you're still inclined:
If gravity and light originate simultaneously at the same source (e.g., the Sun) and propagate to the same target (e.g., the Earth) at the same speed (e.g., c), then aberration will be the same for both. (That is because tan (aberration) = vorbit /Vpropagation
where vorbit is the transverse orbital speed of the target body and
Vpropagation is the propagation speed of field regeneration. Approximately,
aberration vorbit /Vpropagation.) Therefore, gravity and light should produce 3-space accelerations in the same direction (or exact opposite direction, if push and pull are reversed), differing only in magnitude by a scaling constant. Specifically, the momentum transferred to or removed from the target to produce the acceleration is some constant
(usually a mass) times
Vpropagation, a vector, in both cases.
The only physical way to break this equality would require postulating some source of the momentum transfer other than, or in addition to, the propagation speed of the field. Such a postulate would seem to constitute new physics, and would appear to be in trouble with the causality principle because radial forces from the source mass are already spoken for. In the absence of any serious such proposal for a new force, and given that gravity and radiation pressure do not produce anti-parallel forces in experiment (4), one of our premises must be violated. The only premise open to question is the equality of propagation speeds of the two types of force. If gravity propagates very much faster than light, all experimental evidence is immediately satisfied.
We see that all relevant characteristics except possibly field propagation speed are common for the two types of force. Therefore their physical propagation behavior ought to be the same if field propagation speed is the same, or different if field propagation speed is different, because there is nothing else relevant that might distinguish the two types of force. Experiments show without ambiguity that the resulting accelerations are applied in different directions, which implies different field propagation speeds.
To clarify, note than an accelerating target is necessarily changing its momentum vector. Momentum is the product of mass times velocity (or energy over c2 times velocity, if the projectile is massless) for whatever "projectile" carries the force from source to target. The "velocity" in the momentum is the velocity vector of the carrier, whose direction of travel is along the radial from source to target. Because the momentum is necessarily directed along the radial direction, no part of the exchanged momentum could be applied in some other direction. Specifically, if the projectiles are photons and the force is radiation pressure, the target is pushed in the direction of the arriving photons. Whatever is the mechanism of gravity, how could the direction of its pull be other than along the radial to the source mass? The physics and the meanings of words such as "momentum = mass times velocity" dictate only a single possibility for the vector direction of momentum transfers: the radial direction between source mass and target body. And if that is true, the only physical way left to explain the different effective direction of the force is a different propagation speed for a retarded field.
The same remarks apply to electrodynamic forces between charges. If the field propagation speed were lightspeed, we would be forced to interpret the momentum transfers as applied in a different direction from the direction of travel of the momentum carriers because of aberration. That is why, when the details are examined closely, we hear statements such as "virtual 'photons' (the hypothetical carriers of electrodynamic forces, not to be confused with real photons) travel at infinite speeds". So this "lightspeed propagation" assumption is unphysical and unnecessary. One can have the same equations (to the accuracy of observations) and interpret them in a physically consistent way if the momentum carriers travel much faster than light.
Now that we know that Lorentzian relativity is experimentally viable [18] and allows faster-than-light (ftl) propagation in forward time [19], ftl propagation is no longer forbidden in physics, and ftl force carriers are the most reasonable interpretation of the equations. I expect that no one would ever have thought otherwise if they had not mistakenly believed that ftl propagation was forbidden in physics.
If the field around a charge propagated with lightspeed delays, then Maxwell's equations would be wrong because they neglect transverse aberration, the main manifestation of field propagation delay. The fact that the equations are correct to first order in v/c tells us that the field propagation speed must be very fast compared to lightspeed, because the neglect of transverse aberration is the logical equivalent of adopting infinite field propagation speed. If Maxwell's equations did work for fields propagating at lightspeed, then they would work for radiation pressure from light fields too, which they do not. If the field has a measurable delay in reshaping itself to register the motion or acceleration of its source, then one would need to add propagation delay into Maxwell's equations (for example, by taking partials with respect to retarded coordinates instead of instantaneous coordinates). The absence of such propagation delay in the equations means that instantaneous propagation of fields is already built in.
Carlip's paper
In the geometric interpretation of GR, gravity is not a "force" and cannot propagate because target body motion simply follows a curved geodesic path through "space-time" without any force acting. Experiment (5) disputes the possibility that this forceless interpretation of gravity could be correct. So does the dependence of the full GR equations of motion for a target body on that body's own mass. Both are failures of the weak equivalence principle - the notion that "gravity is just geometry".
In his paper [15], Carlip recognizes the concept of gravitational force, as in the field interpretation of GR. But he claims that the experiments (1)-(4) are not direct propagation speed measurements for gravity. They are, however, measurements of aberration or v/V, where the only unknown is the speed of gravity, V. This makes Carlip's point semantic because the "indirectness" of these measures is not significant.
Carlip claims that we have made an implicit assumption that gravitational acceleration is central and has no velocity-dependent terms. If aberration were non-zero, the acceleration would be non-central. However, observations all confirm that it is in fact central to order v/c; i.e., directed along radials from the source mass. GR implies that gravitational acceleration is target-body-velocity dependent at order v2/c2, as shown in equations (2) and (4); but velocity-independent to order v/c. It is also source-mass-velocity dependent in some of the small terms we omitted. However, all these velocity-dependent terms are typically orders of magnitude too small to cancel the aberration term if V = c. So Carlip's point is again irrelevant to this discussion because no velocity-dependent terms exist at first order in v.
If one never considers genuine retardation of propagation between source mass and target body, then infinite propagation speed for gravity is being assumed, whether one says so or not.
Carlip considers his key starting point to be his equation (1.8). Its first term, proportional to ni, represents the transverse aberration. The second term, proportional to vi, cancels this transverse aberration to first order. Similarly, in the GR part of the paper, the corresponding equation where this cancellation occurs is (2.2). These two formulas are the only places where transverse aberration enters Carlip's discussion. However, the alert reader will see that Carlip is beginning with a force vector that points closely toward the true, instantaneous position of the source (to first-order in v), when he should be beginning with a retarded position. In other words, he assumes what he proposes to demonstrate. Obviously, a vector toward the instantaneous source position can be decomposed into an arbitrary pair of component vectors. So it is unremarkable that Carlip decomposes the instantaneous position vector into a retarded position vector plus an update vector for motion during the propagation delay. This merely creates the illusion that he has begun with a retarded position vector, when in fact he has begun with a (nearly) instantaneous position vector formed of two components.
By omitting transverse aberration, Carlip (like many before him) has effectively adopted a field propagation speed . No physical or observational basis exists for postulating V = c.
The most amazing thing I was taught as a graduate student of celestial mechanics at Yale in the 1960s was that all gravitational interactions between bodies in all dynamical systems had to be taken as instantaneous. This seemed unacceptable on two counts. In the first place, it seemed to be a form of "action at a distance". Perhaps no one has so elegantly expressed the objection to such a concept better than Sir Isaac Newton: "That one body may act upon another at a distance through a vacuum, without the mediation of any thing else, by and through which their action and force may be conveyed from one to the other, is to me so great an absurdity, that I believe no man who has in philosophical matters a competent faculty of thinking, can ever fall into it." (See Hoffman, 1983.) But mediation requires propagation, and finite bodies should be incapable of propagate at infinite speeds since that would require infinite energy. So instantaneous gravity seemed to have an element of magic to it.
The second objection was that we had all been taught that Einstein's special relativity (SR), an experimentally well established theory, proved that nothing could propagate in forward time at a speed greater than that of light in a vacuum. Indeed, as astronomers we were taught to calculate orbits using instantaneous forces; then extract the position of some body along its orbit at a time of interest, and calculate where that position would appear as seen from Earth by allowing for the finite propagation speed of light from there to here. It seemed incongruous to allow for the finite speed of light from the body to the Earth, but to take the effect of Earth's gravity on that same body as propagating from here to there instantaneously. Yet that was the required procedure to get the correct answers.
These objections were certainly not new when I raised them. They have been raised and answered thousands of times in dozens of different ways over the years since general relativity (GR) was set forth in 1916. Even today in discussions of gravity in USENET newsgroups on the Internet, the most frequently asked question and debated topic is "What is the speed of gravity?" It is only heard less often in the classroom because many teachers and most textbooks head off the question by hastily assuring students that gravitational waves propagate at the speed of light, leaving the firm impression, whether intended or not, that the question of gravity's propagation speed has already been answered.
Yet, anyone with a computer and orbit computation or numerical integration software can verify the consequences of introducing a delay into gravitational interactions. The effect on computed orbits is usually disastrous because conservation of angular momentum is destroyed. Expressed less technically by Sir Arthur Eddington, this means: "If the Sun attracts Jupiter towards its present position S, and Jupiter attracts the Sun towards its present position J, the two forces are in the same line and balance. But if the Sun attracts Jupiter toward its previous position S', and Jupiter attracts the Sun towards its previous position J', when the force of attraction started out to cross the gulf, then the two forces give a couple. This couple will tend to increase the angular momentum of the system, and, acting cumulatively, will soon cause an appreciable change of period, disagreeing with observations if the speed is at all comparable with that of light." (Eddington, 1920, p.94) See Figure 1.
www.metaresearch.org/cosmology/speed_of_gravity.a
Crazy stuff.
way to click preview. (kicks self)
Speed of Gravity
Apparently gravity travels much faster than the speed of light.
y / peed_limit.asp>The Speed of Gravity
A href=http://www.metaresearch.org/cosmology/gravit
Way cool stuff.
"If the work hadn't been done and there had been disasters wouldn't that have been a greater fiasco? "
That sounds like someone who realizes what was involved.
(Score: -1, Poor reading comprehension.)
Ever make anybody mad Steve?
(Hint - Yes you have.)
I.e. - Accidentally cut someone (a Bad Person) off in traffic who then wrote down your plate number?
Ever get bothered by a strange drunk? Your wife ever get bothered by strangers? She ever make anybody angry? She ever run into a friendly stranger who happens to post pictures to upskirt.com? You say you left the house at 8?
Got any cute little girls in your family? Wonder what time her soccer practice ends?
If you can't care about reasonable privacy for yourself you should consider advocating good privacy for the sake of your loved ones.
Best wishes,
Creepy Guy with an Agenda that involves the Atkinson Family. (NO, not really, all of the above has been to illustrate a point only.)
I'd say most of us here are a big part of the problem.
g es/dilbert2060948020611.gif
http://www.drabble.com/comics/dilbert/archive/ima
You live in PA ?!?
Man, if only I had the power, that is +5 Funny.