SR/GR use absolute time to synchronize the GPS clocks with the ground clock.
in [Physics]
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From: Sam Wormley on 15 Apr 2010 10:01 On 4/15/10 8:43 AM, kenseto wrote: > Sigh...its not my own definition. The term preferred frame means that > a clock at rest in the perferred frame has the special properties that > it is the fastest running clock in the universe and that the speed of > light in the perferred frame is isotropic.....that's why it is called > the preferred frame. > Have you ever heard of the Copernican Principle? 14 July 2005 Letter To the Editor The Tribune In John W Patterson's letter to the Tribune of July 7, he comments on the book, "The Privileged Planet", by Guillermo Gonzalez and Jay W. Richards. John's letter was well crafted illuminating the bigger issue of the creationist movement, provided references and "keywords" that allow interested people to find out more, and he tied the story to Iowa! Very well done! I too, have read the book. I gave my copy to an emeritus professor of chemistry friend of mine, cautioning that he should not read it if he didn't want to raise his blood pressure. Some weeks later he wrote a scathing "book report" to me by email. He was disgusted! For example, concerning the chapter on the Copernican Principle, he wrote, "The authors set up a straw man imbuing the Copernican Principle with a number of ridiculous attributes that they then disparage and in so doing imply that they are destroying a scientific theory. Irritating rubbish!" The Copernican Principle is the philosophical statement that no "special" observers should be proposed. The term originated in the paradigm shift from the Aristotelian model of the heavens, which placed Earth at the center of the Solar system because it appears that everything revolved around Earth. The dictionary defines "principle" as 1. A basic truth, law, or assumption: the principles of democracy. 2. a. A rule or standard, especially of good behavior: a man of principle. b. The collectivity of moral or ethical standards or judgments: a decision based on principle rather than expediency. 3. A rule or law concerning the functioning of natural phenomena or mechanical processes: the principle of jet propulsion. To be clear, principles in physics, are ideas having the ring of truth. But they are not mathematical theories or laws that can be tested empirically such as Einstein's Theory of Relativity. However, they do offer guidance in sniffing out the Laws of nature. The Copernican Principle is one of the most successful scientific hypotheses in the history of science. No serious scientific theories are even proposed that violate the Copernican Principle.
From: Peter Webb on 15 Apr 2010 11:02 Every inertial observer adopted the laws of physics of the absolute frame and that's why every inertial frame has the same laws of physics. _________________________________ If the laws of physics are the same in every inertial frame, what makes one of them the absolute frame?
From: Michael Moroney on 15 Apr 2010 12:05 kenseto <kenseto(a)erinet.com> writes: >On Apr 14, 3:47=A0pm, moro...(a)world.std.spaamtrap.com (Michael Moroney) >wrote: >> kenseto <kens...(a)erinet.com> writes: >> The absolute rest frame, or preferred frame, is _defined_ as a reference >> frame where the laws of physics are different from those in other frames. >> It's "special" because it has its own special laws of physics. >So why can't you describe the differences in the laws of physics >between an inertial frame and an absolute frame? That's kind of like describing the difference between a rabbit and the Easter Bunny. While the properties of a rabbit are well known, what is the Easter Bunny like? Well, every little kid has their own vision of it, with many ideas similar to other kids' ideas. It could be anything, because it doesn't exist, although rabbits do. What is a mythical absolute frame like? Which one? Well, the most common mythical absolute frame is probably the one theorized where the luminiferous aether was stationary, which I guess had all directions appear identical. Non preferred frames had the aether in motion relative to it, so light from one direction (in the direction of aether flow) would behave differently than that from another direction (opposite the aether flow or right angles to it or something). I am not up on the old aether theory since modern physics has no need for it. >> Since SR states that all inertial reference frames have the same laws of >> physics, a special frame where the laws of physics are different cannot >> exist (or is non-inertial). That's why I stated an absolute frame cannot >> exist. >But every inertial observer adopted the laws of physics of the >absolute frame and yet you turn around and claim that the absolute >frame doesn't exist. It's like you claim your mother is not your >mother. No, you are using whatever you defined "absolute frame" to be, not how theoretical physics defines it. What is the frame you call the Absolute Frame? Perhaps it's the frame where a cosmic ray proton, moving at 0.9 c parallel to the north-south axis of Pluto, is stationary. Since that frame is an inertial frame, it can be used as a reference for physics. But to avoid confusion, how about if we call that frame (or whichever frame you call the "absolute frame") Seto's Frame or something, so people don't think we're discussing the absolute frame of aether theory or some other old theory. >All you do is making assertions. Every inertial frame adopt the laws >of physics of the absolute frame and that's why the laws of physics >are the same in every inertial frame. Well, the laws of physics do work if you refer things to that cosmic ray moving at 0.9c relative to Pluto, so that is true. The math is almost always easier if the observer uses the frame that's stationary relative to himself, however. >Every inertial observer adopted the laws of physics of the absolute >frame and that's why every inertial frame has the same laws of >physics. I don't see why any observer would ever adopt that cosmic ray's frame (remember, we'll call it Seto's Frame instead of the absolute frame from now on, to avoid confusion) when the math is so much easier if they use their own frame as a reference. Unless the observer was actually that cosmic ray proton.
From: jem on 16 Apr 2010 09:03 kenseto wrote: > On Apr 14, 3:47 pm, moro...(a)world.std.spaamtrap.com (Michael Moroney) >> Since SR states that all inertial reference frames have the same laws of >> physics, a special frame where the laws of physics are different cannot >> exist (or is non-inertial). That's why I stated an absolute frame cannot >> exist. > > But every inertial observer adopted the laws of physics of the > absolute frame and yet you turn around and claim that the absolute > frame doesn't exist. It's like you claim your mother is not your > mother. > In my left hand is a bag of marbles, one of which is bigger than all the others. In my right hand is another a bag of marbles, all of which are identical to the biggest marble in the left hand bag. Seto logic: All the marbles in the right hand bag are the biggest marble. Why? Because all of them have the unique properties of the biggest marble.
From: kenseto on 16 Apr 2010 11:03
On Apr 15, 11:02 am, "Peter Webb" <webbfam...(a)DIESPAMDIEoptusnet.com.au> wrote: > Every inertial observer adopted the laws of physics of the absolute > frame and that's why every inertial frame has the same laws of > physics. > > _________________________________ > > If the laws of physics are the same in every inertial frame, what makes one > of them the absolute frame? The point is: no inertial frame is the absolute frame....but every inertial frame adopts the laws of physics of the absolute frame and that's why every inertial frames has the same laws of phyiscs. Ken seto |