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Author Topic:   Existence
ICANT
Member
Posts: 6769
From: SSC
Joined: 03-12-2007
Member Rating: 1.5


Message 256 of 1229 (616244)
05-20-2011 2:25 PM
Reply to: Message 253 by NoNukes
05-20-2011 11:35 AM


Re: Time, Clocks, and GR denial
Hi NoNukes,
Sorry about the neglect.
NoNukes writes:
http://tycho.usno.navy.mil/cesium.html
quote:
This frequency is electronically divided down and used in a feedback control circuit ("servo-loop") to keep a quartz crystal oscillator locked to a frequency of 5 megahertz (MHz), which is the actual output of the clock, along with a one-pulse-per-second signal. The entire apparatus is shielded from external magnetic fields.
The third paragraph below the one you quoted says:
quote:
In 1967, the 13th General Conference on Weights and Measures first defined the International System (SI) unit of time, the second, in terms of atomic time rather than the motion of the Earth. Specifically, a second was defined as the duration of 9,192,631,770 cycles of microwave light absorbed or emitted by the hyperfine transition of cesium-133 atoms in their ground state undisturbed by external fields.
Your source agrees with the source I presented.
They both agree that unaffected by a external magnetic fields such as the gravity of earth the frequency will be 9,192,631,770 Hz.
NoNukes writes:
ICANT writes:
quote:
A primary frequency standard in which electronic transitions between the two hyperfine ground states of cesium-133 atoms is used to control the output frequency. (188) Note : The energy level between the two hyperfine ground states corresponds, in the absence of external influences (e.g. , the magnetic field of the Earth), to a frequency of 9,192,631,770 Hz.
emphasis mine.
I would interpert that to say the closer to the earth the slower the frequency. I could be wrong.
NoNukes writes:
The clocks don't have to match. It is enough that we know the degree of mismatch.
My little Tom Tom is not smart enought to figure out the differences from 4 or 5 different satellites. If it does not get the same time stamp from each GPS clock it will not be able to figure out where it is at on the ground.
God Bless,

"John 5:39 (KJS) Search the scriptures; for in them ye think ye have eternal life: and they are they which testify of me."

This message is a reply to:
 Message 253 by NoNukes, posted 05-20-2011 11:35 AM NoNukes has replied

Replies to this message:
 Message 260 by crashfrog, posted 05-20-2011 4:39 PM ICANT has not replied
 Message 261 by NoNukes, posted 05-20-2011 5:36 PM ICANT has not replied
 Message 262 by fearandloathing, posted 05-20-2011 5:38 PM ICANT has not replied

AZPaul3
Member
Posts: 8513
From: Phoenix
Joined: 11-06-2006
Member Rating: 5.3


Message 257 of 1229 (616253)
05-20-2011 3:03 PM
Reply to: Message 245 by ICANT
05-20-2011 2:24 AM


Re: Time
Gravity alone will change the frequency. And if I am not mistaken temperature can also change the frequency.
No, ICANT. Gravity cannot change the frequency. Nor can temperature.
As for temperature, both it and humidity affect the apparatus and can disrupt a proper reading of the frequency measure (not the frequency itself but the apparatus reading the frequency). That is why these clocks are placed under controlled environmental conditions.
As for gravity, again, ICANT, the point being made is that gravity does not affect the frequency of the cesium atoms. The appearent differences seen between reference frames is an actual difference in time itself.
There is no absolute time. There is no favored frame of reference by which we can say a clock is slow or fast. There are only observed differences between frames. And since there can be no absolute special frame of reference by which to measure we cannot say that one frame's clock is right and another frame's clock is wrong.
The cesium atom ticks at the same rate within a reference frame as it does within any other reference frame. Any observed difference we may see from outside the reference frame of the clock is due to time dilation.
I would interpert that to say the closer to the earth the slower the frequency. I could be wrong.
You are.
I see where NoNukes has already answered this.
And I see where you then go on to say:
Your source agrees with the source I presented.
They both agree that unaffected by a external magnetic fields such as the gravity of earth the frequency will be 9,192,631,770 Hz.
If the extent of your most basic knowledge of reality is that gravity is a magnetic field then there is no hope in trying to explain reality to someone so massively screwed up.
I'm done here.
Edited by AZPaul3, : No reason given.

This message is a reply to:
 Message 245 by ICANT, posted 05-20-2011 2:24 AM ICANT has not replied

Taq
Member
Posts: 9973
Joined: 03-06-2009
Member Rating: 5.7


Message 258 of 1229 (616257)
05-20-2011 3:53 PM
Reply to: Message 235 by ICANT
05-19-2011 2:41 PM


Re: Time
So according to that the satellite clocks are adjustable and are adjusted to keep the exact time the clock on earth does.
And they have to do so by adjusting the definition of time. These numbers are way off, but they have to redefine an hour as taking 61 minutes instead of 60. This is because time moves more quickly for the satellites compared to an observer on the surface of the Earth. Even with this internal correction the time on the satellites has to be constantly reset by ground control.
Edited by Taq, : No reason given.

This message is a reply to:
 Message 235 by ICANT, posted 05-19-2011 2:41 PM ICANT has not replied

Theodoric
Member
Posts: 9076
From: Northwest, WI, USA
Joined: 08-15-2005
Member Rating: 3.7


Message 259 of 1229 (616266)
05-20-2011 4:21 PM
Reply to: Message 245 by ICANT
05-20-2011 2:24 AM


One question
Do you think these two things are equal?
Magnetic field
Gravitation

Facts don't lie or have an agenda. Facts are just facts

This message is a reply to:
 Message 245 by ICANT, posted 05-20-2011 2:24 AM ICANT has not replied

crashfrog
Member (Idle past 1467 days)
Posts: 19762
From: Silver Spring, MD
Joined: 03-20-2003


Message 260 of 1229 (616269)
05-20-2011 4:39 PM
Reply to: Message 256 by ICANT
05-20-2011 2:25 PM


Re: Time, Clocks, and GR denial
They both agree that unaffected by a external magnetic fields such as the gravity of earth the frequency will be 9,192,631,770 Hz.
Gravity is not a magnetic field, and moreover - the clock in space and the clock on Earth both "tick" at 9.192 ghz. If you're standing by the clock on Earth, it's ticking at 9.192 ghz. If you're standing by the one in space, it's ticking at 9.192 ghz.
But the one in space has to be "corrected" - adjusted - to match the one on Earth (where we live, and therefore where we would like to tell time) because on Earth seconds are longer than they are in orbit.
This is because gravitational fields don't change the way clocks run, they change the way time runs.
If it does not get the same time stamp from each GPS clock it will not be able to figure out where it is at on the ground.
It's actually the difference in times that your GPS uses to locate itself.

This message is a reply to:
 Message 256 by ICANT, posted 05-20-2011 2:25 PM ICANT has not replied

NoNukes
Inactive Member


Message 261 of 1229 (616278)
05-20-2011 5:36 PM
Reply to: Message 256 by ICANT
05-20-2011 2:25 PM


Re: Time, Clocks, and GR denial
ICANT writes:
Hi NoNukes,
Sorry about the neglect.
No apology necessary. You are busy.
ICANT writes:
They both agree that unaffected by a external magnetic fields such as the gravity of earth the frequency will be 9,192,631,770 Hz.
You've made a fundamental error here.
Gravity is not a magnetic field. A reference that talks about the effect of magnetic fields does nothing to confirm an effect from gravitational fields. Thus your interpretation is wrong. The quote you provided says nothing about the effect of gravity.
Magnetic fields affect cesium clocks because the clock is based on the energy difference between states of a cesium atom in a magnetic field. Stray magnetic fields interfere with the mechanism for detecting the characteristic frequency. Gravitational fields would not have the same affect.
As per the source I provided, atomic clocks are shielded from magnetic fields and are maintained in a temperature controlled environment. So in their own frame of reference, they generate a frequency of 9,192,631,770 Hz.
My little Tom Tom is not smart enought to figure out the differences from 4 or 5 different satellites. If it does not get the same time stamp from each GPS clock it will not be able to figure out where it is at on the ground.
ICANT, you cannot just make up facts. You have no idea what your li'l Tom Tom is capable of. And regardless of what you think the Tom Tom does, you've been shown multiple sources indicating that some relativity corrections are performed at the receiver.

This message is a reply to:
 Message 256 by ICANT, posted 05-20-2011 2:25 PM ICANT has not replied

fearandloathing
Member (Idle past 4145 days)
Posts: 990
From: Burlington, NC, USA
Joined: 02-24-2011


Message 262 of 1229 (616280)
05-20-2011 5:38 PM
Reply to: Message 256 by ICANT
05-20-2011 2:25 PM


Re: Time, Clocks, and GR denial
Here is yet another paper which discusses relativistic effects on clocks. It would be nice if you could provide some papers/data to support you. All you seem to do is cherry pick bits and pieces of data others provide to try and support your view, ignoring the rest of the evidence that you dont like. Taking things out of context in order to try and support your argument is ...well ineffective at best.
You have been provided a ton of data, in its full, not cherry picked. Can you do the same?? I would like to see specific evidence that gravity is the only effect that needs to be accounted for when dealing with gps, full paper, not something you quote mined.
Edited by fearandloathing, : No reason given.
Edited by fearandloathing, : No reason given.

"I hate to advocate the use of drugs, alcohol, violence, or insanity to anyone, but they always worked for me." - Hunter S. Thompson
Ad astra per aspera

This message is a reply to:
 Message 256 by ICANT, posted 05-20-2011 2:25 PM ICANT has not replied

fizz57102
Junior Member (Idle past 4006 days)
Posts: 17
Joined: 05-24-2010


Message 263 of 1229 (616528)
05-23-2011 4:22 AM


ICANT is not alone
From http://www.phys.lsu.edu/mog/mog9/node9.html:
quote:
At the time of launch of the first NTS-2 satellite (June 1977), which contained the first Cesium clock to be placed in orbit, there were some who doubted that relativistic effects were real. A frequency synthesizer was built into the satellite clock system so that after launch, if in fact the rate of the clock in its final orbit was that predicted by GR, then the synthesizer could be turned on bringing the clock to the coordinate rate necessary for operation. The atomic clock was first operated for about 20 days to measure its clock rate before turning on the synthesizer. The frequency measured during that interval was 442.5 parts in 10^12 faster than clocks on the ground; if left uncorrected this would have resulted in timing errors of about 38,000 nanoseconds per day. The difference between predicted and measured values of the frequency shift was only 3.97 parts in 10^12, well within the accuracy capabilities of the orbiting clock. This then gave about a 1% validation of the combined motional and gravitational shifts for a clock at 4.2 earth radii.
Actually the way I first heard it, there was a third camp of engineers who thought that the effect was in the opposite direction, so the clock module had three settings, with a +, 0 and - correction.
From the same source, it seems that it is technically incorrect to say that GPS provides a continuous demonstration of gr:
quote:
At present one cannot easily perform tests of relativity with the system because the SV clocks are actively steered to be within 1 microsecond of Universal Coordinated Time (USNO).
Edited by fizz57102, : No reason given.

Replies to this message:
 Message 264 by fearandloathing, posted 05-23-2011 9:39 AM fizz57102 has replied

fearandloathing
Member (Idle past 4145 days)
Posts: 990
From: Burlington, NC, USA
Joined: 02-24-2011


Message 264 of 1229 (616557)
05-23-2011 9:39 AM
Reply to: Message 263 by fizz57102
05-23-2011 4:22 AM


Re: ICANT is not alone
So I guess you dont believe in relativity either.
The question isn't whether the effects of relativity are negligible. The question is it real,and the answer is yes based on your evidence.
from your link writes:
Several relativistic effects are too small to affect the system at current accuracy levels, but may become important as the system is improved; these include gravitational time delays, frequency shifts of clocks in satellites due to earth's quadrupole potential, and space curvature.
This system was intended primarily for navigation by military users having access to encrypted satellite transmissions which are not available to civilian users. Uncertainty of position determination in real time by using the Precise Positioning code is now about meters. Averaging over time and over many satellites reduces this uncertainty to the point where some users are currently interested in modelling many effects down to the millimeter level. Even without this impetus, the GPS provides a rich source of examples for the applications of the concepts of relativity.
Thanks for more evidence to support my position.

"I hate to advocate the use of drugs, alcohol, violence, or insanity to anyone, but they always worked for me." - Hunter S. Thompson
Ad astra per aspera
Nihil curo de ista tua stulta superstitione.

This message is a reply to:
 Message 263 by fizz57102, posted 05-23-2011 4:22 AM fizz57102 has replied

Replies to this message:
 Message 267 by crashfrog, posted 05-23-2011 10:47 AM fearandloathing has not replied
 Message 282 by fizz57102, posted 05-24-2011 4:59 AM fearandloathing has replied

granpa
Member (Idle past 2341 days)
Posts: 128
Joined: 10-26-2010


Message 265 of 1229 (616559)
05-23-2011 9:47 AM


GPS and Relativity
quote:
Because an observer on the ground sees the satellites in motion relative to them, Special Relativity predicts that we should see their clocks ticking more slowly (see the Special Relativity lecture). Special Relativity predicts that the on-board atomic clocks on the satellites should fall behind clocks on the ground by about 7 microseconds per day because of the slower ticking rate due to the time dilation effect of their relative motion.
Further, the satellites are in orbits high above the Earth, where the curvature of spacetime due to the Earth's mass is less than it is at the Earth's surface. A prediction of General Relativity is that clocks closer to a massive object will seem to tick more slowly than those located further away (see the Black Holes lecture). As such, when viewed from the surface of the Earth, the clocks on the satellites appear to be ticking faster than identical clocks on the ground. A calculation using General Relativity predicts that the clocks in each GPS satellite should get ahead of ground-based clocks by 45 microseconds per day.

granpa
Member (Idle past 2341 days)
Posts: 128
Joined: 10-26-2010


Message 266 of 1229 (616560)
05-23-2011 9:52 AM


Relativity in the Global Positioning System
quote:
There is an interesting story about this frequency offset. At the time of launch of the NTS-2 satellite (23 June 1977), which contained the first Cesium atomic clock to be placed in orbit, it was recognized that orbiting clocks would require a relativistic correction, but there was uncertainty as to its magnitude as well as its sign. Indeed, there were some who doubted that relativistic effects were truths that would need to be incorporated [5]! A frequency synthesizer was built into the satellite clock system so that after launch, if in fact the rate of the clock in its final orbit was that predicted by general relativity, then the synthesizer could be turned on, bringing the clock to the coordinate rate necessary for operation. After the Cesium clock was turned on in NTS-2, it was operated for about 20 days to measure its clock rate before turning on the synthesizer [11]. The frequency measured during that interval was +442.5 parts in 1012 compared to clocks on the ground, while general relativity predicted +446.5 parts in 1012. The difference was well within the accuracy capabilities of the orbiting clock. This then gave about a 1% verification of the combined second-order Doppler and gravitational frequency shift effects for a clock at 4.2 earth radii.
Additional small frequency offsets can arise from clock drift, environmental changes, and other unavoidable effects such as the inability to launch the satellite into an orbit with precisely the desired semimajor axis. The navigation message provides satellite clock frequency corrections for users so that in effect, the clock frequencies remain as close as possible to the frequency of the U.S. Naval Observatory’s reference clock ensemble. Because of such effects, it would now be difficult to use GPS clocks to measure relativistic frequency shifts

crashfrog
Member (Idle past 1467 days)
Posts: 19762
From: Silver Spring, MD
Joined: 03-20-2003


Message 267 of 1229 (616570)
05-23-2011 10:47 AM
Reply to: Message 264 by fearandloathing
05-23-2011 9:39 AM


Re: ICANT is not alone
So I guess you dont believe in relativity either.
I think by "not alone" he's referring to the engineers referred to in the quote, the ones who doubted that GR corrections would need to be made - not his own beliefs.

This message is a reply to:
 Message 264 by fearandloathing, posted 05-23-2011 9:39 AM fearandloathing has not replied

Replies to this message:
 Message 268 by NoNukes, posted 05-23-2011 12:10 PM crashfrog has not replied

NoNukes
Inactive Member


Message 268 of 1229 (616574)
05-23-2011 12:10 PM
Reply to: Message 267 by crashfrog
05-23-2011 10:47 AM


Re: ICANT is not alone
crashfrog writes:
I think by "not alone" he's referring to the engineers referred to in the quote, the ones who doubted that GR corrections would need to be made - not his own beliefs.
That is certainly what was meant. But I think ICANT is essentially alone. He has a fairly unique denial pattern.
ICANT does not agree with those engineers. ICANT believes that some kind of gravitational effect works on clocks to produce a slowing exactly at the rate predicted for gravitational time dilation. Those engineers in the article the would not have expected the effect ICANT acknowledges.
Apparently ICANT does not accept the time dilation predicted by Special Relativity due to relative motion between frames. Although I haven't seen an explicit statement of that, he does reject the twin paradox as being a mere thought experiment, and he hasn't really addressed the relativistic mu-meson decay experiments.

This message is a reply to:
 Message 267 by crashfrog, posted 05-23-2011 10:47 AM crashfrog has not replied

Replies to this message:
 Message 269 by ICANT, posted 05-23-2011 2:44 PM NoNukes has replied

ICANT
Member
Posts: 6769
From: SSC
Joined: 03-12-2007
Member Rating: 1.5


Message 269 of 1229 (616609)
05-23-2011 2:44 PM
Reply to: Message 268 by NoNukes
05-23-2011 12:10 PM


Re: ICANT is not alone
Hi NoNukes,
NoNukes writes:
Apparently ICANT does not accept the time dilation predicted by Special Relativity due to relative motion between frames.
ICANT don't believe time can be dilated.
Dilated meaning streached or expanded.
You can not streach time like you can bubble gum.
Time is a concept of man. A concept can not be streached.
An object can be streached or shortned.
What kind of an object is time?
So could you give me a definition of the time that you are streaching when you talk about time dilation?
God Bless,

"John 5:39 (KJS) Search the scriptures; for in them ye think ye have eternal life: and they are they which testify of me."

This message is a reply to:
 Message 268 by NoNukes, posted 05-23-2011 12:10 PM NoNukes has replied

Replies to this message:
 Message 270 by Taq, posted 05-23-2011 3:00 PM ICANT has replied
 Message 271 by NoNukes, posted 05-23-2011 3:34 PM ICANT has replied
 Message 272 by crashfrog, posted 05-23-2011 4:20 PM ICANT has replied
 Message 346 by Jaderis, posted 06-02-2011 3:45 AM ICANT has replied

Taq
Member
Posts: 9973
Joined: 03-06-2009
Member Rating: 5.7


Message 270 of 1229 (616614)
05-23-2011 3:00 PM
Reply to: Message 269 by ICANT
05-23-2011 2:44 PM


Re: ICANT is not alone
ICANT don't believe time can be dilated.
Dilated meaning streached or expanded.
You can not streach time like you can bubble gum.
Then what word should we use for the observed fact that time moves at different rates in different frames of reference?
So could you give me a definition of the time that you are streaching when you talk about time dilation?
We could use the amount of time it takes for light to travel one meter. The oscillation of cesium has been mentioned before. Pretty much any physical interaction that depends on time would be applicable. For example, the rate at which iron is oxidized by free oxygen could be used. The rate at which a specific pendulum swings.

This message is a reply to:
 Message 269 by ICANT, posted 05-23-2011 2:44 PM ICANT has replied

Replies to this message:
 Message 273 by ICANT, posted 05-23-2011 9:40 PM Taq has replied

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