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The One Way Speed Of Light

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#1 piasan

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Posted 14 August 2015 - 12:52 AM

Cross posted from "Barriers preventing Micro" .....

Light Years is not a "TIME" measure..but a Distance.  To validate your clumsy claim here, please post the One-Way Speed of Light...?

We have been thru this before......

 

The one way speed of light is (roughly) 300 million meters per second.  Or 9.46 trillion kilometers per year.  We know this because we've been using that one-way speed of light to navigate everything from spacecraft to hiking trails for over 70 years.  If the one way speed of light were anything but 300 million meters per second, the GPS many of us have in our cars wouldn't work.

 

#### end cross posted material ####

 

The leading creation scientist proposing the idea the one way speed of light may be direction dependent is Dr. Jason Lisle with his Anisotropic Synchrony Convention.  Lisle proposes an infinite speed of light from the source to the destination but only half speed from the destination back to the source.  This would solve the light travel time problem of YEC while giving the experimental (round trip) value for the speed of light.

 

During World War II, the LORAN navigation network was developed.  This works by a master station sending a pulse which slave stations rebroadcast.  Measuring the time difference between the signals would allow a position fix.

 

In the 1970's, I stood navigation watches on a nuclear missile submarine.  I actually performed LORAN-C fixes to verify our navigation system.  The LORAN fixes were accurate to within about a foot per mile from the station.  We also had a satellite navigation system.  Neither of those navigation systems would work if the speed of light were direction dependent.

 

Many of us have a GPS in our car.  These devices are usually accurate to within about 50 feet.  GPS uses the time difference in the arrival of satellite signals to calculate our position.  Any directional change would render the entire GPS system useless.

 

Oh yeah.... I think everyone knows a light-year is a distance.  As it happens, it is the distance light travels in a year.  For that reason, if an object is 167,000 light years from us, it takes 167,000 years for the light from that object to reach us.

 

Enoch has had an open invitation for more than a year to show how either GPS or LORAN will work if the one-way speed of light is anything but 300 million meters per second. 



#2 Schera Do

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Posted 14 August 2015 - 04:13 AM

...
Actually, there are several people who directly observe the early life of the universe. They are astrophysicists, and they conclude that light sources exist way beyond the 6000 light-year of a created universe.
....

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...
Light Years is not a "TIME" measure..but a Distance. To validate your clumsy claim here, please post the One-Way Speed of Light...? ...

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I wondered about the "clumsy claim".

#3 piasan

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Posted 14 August 2015 - 01:07 PM

cross-posted from the "Barriers Preventing Micro -->Macro discussion....

 

 God expanded His created universe after He created it and the stars and galaxies appeared much closer then than now.

How do you know?

Because God Almighty said so, that's why. Quote:  "Thus saith the LORD, thy redeemer, and he that formed thee from the womb, I am the LORD that maketh all things; that stretcheth forth the heavens alone." Isaiah 44:24 That's just one of seventeen verses from scripture that tell us that God expanded His creation after He made it all. 
 
So what they saw in ancient times was something like this:
 
starryskyinAdamstimeperhaps.jpg

 

 

Nice artist illustration.  I'll give it exactly the same credibility as I expect you would if I presented a similar artist illustration of the view from an exoplanet.

 

Now.... since God expanded His creation, why didn't the light stretch also?

 

(This is probably off topic from "Barriers Preventing Micro-Macro, so I'm going to cross post this to the "One way speed of light" discussion.



#4 piasan

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Posted 14 August 2015 - 01:20 PM

Light Years is not a "TIME" measure..but a Distance.  To validate your clumsy claim here, please post the One-Way Speed of Light...?

I wondered about the "clumsy claim".

It's probably that he thinks you don't realize the difference between distance and time.

 

Just so Enoch understands .....  Supernova Sn1987a is 167,000 light years (ly) or 1.58x1018 or 1.58 billion billion kilometers.   Using the simple equation:   Time = distance / velocity we get  1,580,000,000,000,000,000 km divided by 9,460,000,000,000 km/yr  = 167,000 years.

 

Based on previous experience, I predict Enoch will probably not bother to reply in any substantive way..... but we can be certain he will ask again what the "one-way speed of light" is.



#5 Schera Do

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Posted 14 August 2015 - 01:53 PM

I wondered about the "clumsy claim".

.

It's probably that he thinks you don't realize the difference between distance and time.
...

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I didn't make any statements about distance or time and he didn't make the response to me and I didn't make the "wonder" post in regards to anything except to provide context where it was missing: I'm thinking, "no good deed goes unpunished".

Oy.

#6 Iguana

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Posted 14 August 2015 - 10:26 PM

I've always found it incredibly telling and almost hilarious whenever a creationist speaks against the speed of light. Series of anecdotes: There was a science-fair-type thing in my school on Thursday. Two separate groups of kids (one of which was comprised of 14-year-olds, mind you) measured the speed of light to about 10% accuracy using methods based on the idea that light travels at the same speed always. I have personally performed several such experiments myself. Last week I visited the optics department of a local engineering-focused college. Literally nothing in that room would work if the speed of light were variable. Einstein's equations would fall apart, but Enoch doesn't even care about that, so I'll say this: Maxwell's equations would fall apart, I'd love to see him dispute those. A constant speed of light has been at the foundation of all of physics even before Einstein, heck, maybe even before Maxwell. Whenever I see a creationist arguing against the speed of light, I pretty much know they'll never change their minds. Calling it foundational is doing it a disservice.

 

I'm probably just nerding out right now, but every single commonly-used equation with the term 'c' works. It's that simple. Every single one works, and there are a LOT of equations that use that term. When a creationist says that the speed of light is variable, they are arguing against all those equations. It almost seems hilarious when a 14-year-old kid can see the speed of light by his or herself and yet a creationist can't.



#7 piasan

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Posted 15 August 2015 - 12:53 AM

I've always found it incredibly telling and almost hilarious whenever a creationist speaks against the speed of light.

The basic question is, of course, how long it takes the light to reach us.  As I pointed out, it's a really simple equation that many of us on a regular basis.

 

Time = Distance / Velocity.

 

In my time, I've seen creationists first challenge the distances; then the speed of light; then time itself.  Having failed at all of these, the most recent argument is that the speed of light may be direction dependent.

 

Series of anecdotes: There was a science-fair-type thing in my school on Thursday. Two separate groups of kids (one of which was comprised of 14-year-olds, mind you) measured the speed of light to about 10% accuracy using methods based on the idea that light travels at the same speed always. I have personally performed several such experiments myself.

The problem with those experiments is that it is assumed light travels at the same speed always.  Round-trip (interferometer) experiments based on that assumption do not measure the one way speed.  So they don't address the question.

 

Lisle, in his Anisotropic Synchrony Convention (ASC) argues for an infinite speed of light toward the observer but only half of "c" back to the source.  As I've already pointed out, this would solve the light travel time of YEC because it would mean, for example, that the supernova explosion Sn1987a would have actually taken place in February, 1987, as the light from the event would reach us instantly.

 

Lisle also argues it is impossible to test the one way speed of light because one cannot synchronize clocks.  Unfortunately, this is easily overcome.  Lisle is correct that moving one, or both clocks after synchronizing them could destroy the synchronization due to relativistic effects.  There are two ways to overcome this obstacle.

 

First:  Relativistic effects of moving clocks slowly for a (relatively) short distance would be insignificant compared to the scale of change claimed by Lisle.  Also, since the relativistic effects of moving objects are well known, the clocks could simply be adjusted for them.

 

Second:  Put three stations in a straight line with the center station exactly half way between the other two.  Send a pulse from the center station to the end stations.  Under either ASC or the standard model, the clocks will be synchronized.  Then, at a predetermined time send a pulse from one end station to the other.  It would be a simple matter to see if it arrived instantly or not.

 

But, we really don't need to go to all that trouble.  The problem only exists when there is only one source and only one destination.  In the case of GPS, the satellites are transmitting to (probably) millions of receivers at varying distances in a one-way transmission.  These receivers then calculate their position based on the travel time of the signals from the satellites being tracked..... based on the velocity of light being 300,000,000 m/s in all directions.  If the signals were travelling at any other speed, a solution would not be possible and the system would not work.

 

Whether the operation of radio-navigation systems is not a "straight line" experiment of directional consistency of "c," it does serve as operational confirmation that the speed of light is the same in all directions.

 

It must be pretty bad to have your primary argument refuted by a device many of have in our cars and/or cell phones.


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#8 Schera Do

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Posted 16 August 2015 - 03:51 AM

unitconversion.org: "A lightyear is the distance light travels in vacuum in one Julian year. A light-year is equal to 9,460,730,472,580.8 km (about 9.461 Pm) or about 5,878,625,373,183.61 statute miles or about 63,241.077 AU (often approximated to 63,240 AU) or about 0.306 601 394 parsecs. The actual, exact length of the light-year depends on the length of the reference year used in the calculation, and there is no wide consensus on the reference to be used."

paisan, I determined that the 'm' in your "300,000,000 m/s" is meters. Here is a question and test of critical analysis skils for the peanut gallery.

Given that 300,000,000 is perfectly divisible by the length of a meter and we know that lengths of metric distances were created by some process of selection, which came first (created first) the number representing the length light travels per second or the length of a meter? (We are not concerned with the reason for selecting the numerator representing time [duration] in the ratio distance/time to be second.)

#9 Iguana

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Posted 16 August 2015 - 04:05 PM

unitconversion.org: "A lightyear is the distance light travels in vacuum in one Julian year. A light-year is equal to 9,460,730,472,580.8 km (about 9.461 Pm) or about 5,878,625,373,183.61 statute miles or about 63,241.077 AU (often approximated to 63,240 AU) or about 0.306 601 394 parsecs. The actual, exact length of the light-year depends on the length of the reference year used in the calculation, and there is no wide consensus on the reference to be used."

paisan, I determined that the 'm' in your "300,000,000 m/s" is meters. Here is a question and test of critical analysis skils for the peanut gallery.

Given that 300,000,000 is perfectly divisible by the length of a meter and we know that lengths of metric distances were created by some process of selection, which came first (created first) the number representing the length light travels per second or the length of a meter? (We are not concerned with the reason for selecting the numerator representing time [duration] in the ratio distance/time to be second.)

The meter has been defined for years now as one 299,792,458th of a light second, a light-second being the distance light travels in a second in any inertial reference frame, and a second being 9,192,631,770 periods of the transition between the two levels of the ground state of a cesium 133 atom.

 

Other definitions have been used for the meter, but they were eventually changed to this one once the speed of light was measured to great accuracy. (I think the current margin of error is somewhere around a tenth of a millimeter per second, but don't quote me on that one)



#10 Calypsis4

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Posted 16 August 2015 - 05:24 PM

.
.
I wondered about the "clumsy claim".

 

The absolute arrogance you guys have in claiming to know what the speed of light was in very ancient times....as if God Almighty is incapable of changing the nature of light at any time for any reason. The expansion of the universe is mentioned 17 times in the Bible which means He could have changed the nature and/or velocity of light that many times.

 

But the fact is that you won't even admit that the speed of light constant may not be a constant at all...as testified by great number of evolutionist scientists. 

Examples:

 

So if you won't take heed to any of your comrades in accidentalism then it is little wonder that you won't believe us.



#11 piasan

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Posted 16 August 2015 - 07:45 PM

paisan, I determined that the 'm' in your "300,000,000 m/s" is meters. Here is a question and test of critical analysis skils for the peanut gallery.

Yeah.  Sorry, I sometimes bounce back and forth between measurement systems.  Often, I will provide units in both metric (SI) and English systems as a convenience to readers.  If it were miles, I would have used "mi" rather than "m."  We should get a clue .... even England has abandoned the English system of measurements.

 

Given that 300,000,000 is perfectly divisible by the length of a meter and we know that lengths of metric distances were created by some process of selection, which came first (created first) the number representing the length light travels per second or the length of a meter? (We are not concerned with the reason for selecting the numerator representing time [duration] in the ratio distance/time to be second.)

Well, the speed of light was first measured by Roemer in 1676.  The meter wasn't first defined until 1793.  So, the representation of distance couldn't have been in meters.  I have no idea what the unit of length used in 17th century Denmark was, but conversion from one unit of measure to another is a fairly simple matter. 

 

The definition of the "meter"  has also been changed from time to time as technology for measuring distances has improved our precision.



#12 piasan

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Posted 16 August 2015 - 09:58 PM

The absolute arrogance you guys have in claiming to know what the speed of light was in very ancient times....

Well, we may not know what it was in very ancient times, but we can tell what it was (within a few percent) when it left Sn1987a (distance 167,000+ light years).  Also, Australian physicist Paul Davies established that it was within 0.001% of current observed values when it left galaxies 12 billion light years from Earth.

 

Also, significant changes in the speed of light have other consequences..... such as an increase in the energy output of the sun.

 

 

 ....as if God Almighty is incapable of changing the nature of light at any time for any reason.

Of course He can.  However, when He does so, He is acting outside the sphere of investigation by the physical and natural sciences.  They must go by the evidence God gives us in His creation.  Further, because the universe has all the appearances of being billions of years old, rather than thousands, there are some serious theological problems with creation looking so old.  (Those would be more appropriate for one of the "Theistic Evolution" threads.)

 

 

The expansion of the universe is mentioned 17 times in the Bible which means He could have changed the nature and/or velocity of light that many times.

And such changes would leave His fingerprints that they have taken place.

 

But the fact is that you won't even admit that the speed of light constant may not be a constant at all...as testified by great number of evolutionist scientists. 

Well, I really don't need the speed of light to be constant .... and I've never said it is.  All that is necessary for billions of years is that the speed of light be stable and consistent.  On the other hand, YEC would need the speed of light to be, on average, more than 2 million times faster than present values for us to even see the most distant objects.... such as the galaxies studied by Davies.

 

 

Examples: .....

 

So if you won't take heed to any of your comrades in accidentalism then it is little wonder that you won't believe us.

I guess with 9 examples, you could be accused of elephant hurling.  However, I notice 4 are within a week of each other in Jan, 2015, and another 2 are within a week of each other in April, 2013.  So, I suspect you have engaged in your usual habit of citing multiple articles about the same paper as if the 1 paper counts as 4.  Come to think of it, that probably is "elephant hurling."

 

That said, I'll address them in a separate post.

 

As for taking "heed" of what these papers say.... You have previously claimed I "dis" these sources.  Now, I'm not sure if you mean "disrespect" or "disregard."  However, I have never treated any of these sources disrespectfully.

 

What I have done is evaluate the impact of these proposals as if they are true.  Is there something wrong with that?  If past experience is any indicator, at most, they amount to minute fractions of a percent.  Compare that to the 200,000,000+ percent change in the average speed of light needed by YEC.



#13 Schera Do

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Posted 16 August 2015 - 10:35 PM

The meter has been defined for years now as one 299,792,458th of a light second, a light-second being the distance light travels in a second in any inertial reference frame, and a second being 9,192,631,770 periods of the transition between the two levels of the ground state of a cesium 133 atom.

Other definitions have been used for the meter, but they were eventually changed to this one once the speed of light was measured to great accuracy. (I think the current margin of error is somewhere around a tenth of a millimeter per second, but don't quote me on that one)

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Oh, my. When I saw the second (and third) references to 300,000,000 m/s in my internet searches after paisan's reference, I thought that I had either found proof of God--a.k.a. a "challenge to my agnosticism"--or that someone had chosen the length of meter to be divisible perfectly by the speed of light.

Around here, that kind of mistake would be called "intelligent design" and be the impetus for numerous threads.

Hey, that's pretty funny...I couldn't resist. I should have known as there have been very few challenges to my agnosticism.
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Yeah. Sorry, I sometimes bounce back and forth between measurement systems. Often, I will provide units ....

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It should be clear now that, while you caused the initial confusion, it had nothing to do with bouncing "back and forth between measurement systems".
.

... Well, the speed of light was first measured by Roemer in 1676. The meter wasn't first defined until 1793. So, the representation of distance couldn't have been in meters. I have no idea what the unit of length used in 17th century Denmark was, but conversion from one unit of measure to another is a fairly simple matter.

The definition of the "meter" has also been changed from time to time as technology for measuring distances has improved our precision.

.
I'm not sure that you understand my reaction to your--otherwise--harmless misrepresentation (using 300,000,000 for 299,792,458). This has be a fortuitous misrepresentation. When I saw the '3' with all those trailing zeros my bull-bleep detector went into high dungeon!! It had to be either a contrivance or proof of God.

Now do you understand the reason I posed "a question and test of critical analysis skil[l]s for the peanut gallery"?

This is very pertinent to the subject of this forum. I wasn't attempting to play or have fun.

Imagine that the length of meter was determined and fixed before the speed of light were determined.

What would be some of the first things one would do when given the profound, "universal" value of the speed of light?

One thing would be to calculate how many meters are traversed in one second.

What would be your reaction if the result were 300,000,000?

One would expect something that had the imprecision of the actual value, 299,792,458. (FYI, the value in yards is 327,857,018.81.)

Thank you for the information: I do find it very noteworthy that the length of 'meter' has been adjusted "from time to time".
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Now, one last thing...
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The meter has been defined for years now as one 299,792,458th of a light second, a light-second being the distance light travels in a second in any inertial reference frame, and a second being 9,192,631,770 periods of the transition between the two levels of the ground state of a cesium 133 atom.
...

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No. a 'Second' being the duration 1/86400 of Earth's rotation.

#14 Schera Do

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Posted 16 August 2015 - 11:45 PM

I chose two links from Calypsi's list. No, they were not random selections.

sciencenews.org
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Generally if light is not traveling at c it is because it is moving through a material. For example, light slows down when passing through glass or water.
...
The researchers produced pairs of photons and sent them on different paths toward a detector. One photon zipped straight through a fiber. The other photon went through a pair of devices that manipulated the structure of the light and then switched it back. Had structure not mattered, the two photons would have arrived at the same time. But that didn’t happen. Measurements revealed that the structured light consistently arrived several micrometers late per meter of distance traveled.

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This probably is a silly question. The two media ("paths") don't violate the requirement of vacuum? The issue is the constancy of the subject's speed within a vacuum.

math.ucr.edu
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The SI Committee could not just define [metre] to be constant; instead, they would have to fix the definition of the metre by stating which colour of light was being used. Experiments have shown that the mass of the photon must be very small if it is not zero ...


I am gratified as I always resist the notion of a "massless" entity. Yes, I know the photon at rest could have no mass. We all know that no one believes a stationary photon to exist, or rather, that one will be found.
 

The absolute arrogance you guys have in claiming to know what the speed of light was in very ancient times... ...

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Don't count me in. I don't make any claim of knowing "the speed of light ... in very ancient times".
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...
But the fact is that you won't even admit that the speed of light constant may not be a constant at all... ...

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Don't count me in. I've never had the opportunity to "admit" such a thing as I've never heard of that thing before reading the content at the links.
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...as if God Almighty is incapable of changing the nature of light at any time for any reason.

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Did you give the lists of examples so that we could learn of humans affecting the speed of light by "changing the nature of light" as described in at the sciencenews link? To wit:

"A new experiment reveals that focusing or manipulating the structure of light pulses reduces their speed, ..."

Did those scientists do a "God Almighty" imitation?

Let's get one thing straight: It is your definition of God which permits "changing the nature of light at any time for any reason".

------------Edit01---------------------
 

...
As for taking "heed" of what these papers say.... You have previously claimed I "dis" these sources. Now, I'm not sure if you mean "disrespect" or "disregard." However, I have never treated any of these sources disrespectfully.
...

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I do believe that the original word was 'dismiss'.

#15 piasan

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Posted 16 August 2015 - 11:53 PM

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Oh, my. When I saw the second (and third) references to 300,000,000 m/s in my internet searches after paisan's reference, I thought that I had either found proof of God--a.k.a. a "challenge to my agnosticism"--or that someone had chosen the length of meter to be divisible perfectly by the speed of light.

Around here, that kind of mistake would be called "intelligent design" and be the impetus for numerous threads.

Hey, that's pretty funny...I couldn't resist. I should have known as there have been very few challenges to my agnosticism.
.
.
It should be clear now that, while you caused the initial confusion, it had nothing to do with bouncing "back and forth between measurement systems".
.
.
I'm not sure that you understand my reaction to your--otherwise--harmless misrepresentation (using 300,000,000 for 299,792,458). This has be a fortuitous misrepresentation. When I saw the '3' with all those trailing zeros my bull-bleep detector went into high dungeon!! It had to be either a contrivance or proof of God.

Well, when I first responded to Enoch on the other thread, I did say "roughly" 300 million. 

 

I went to school in "BC" times.   (Before Calculators.)  We did all our math with slide rules and log tables.  Answers with ten significant digits simply weren't realistic.  Logarithms to 4 digits were looked up on a table and we could "extrapolate" another digit if needed.  Slide rules are considered useful to three significant digits.... so that's how I do most of my math.  Since 299,792,458 to three significant digits rounds off to 300 million, that's the number I use.

 

The meter was initially defined as one ten millionth the distance from the equator to the North Pole.  As I said, the definition has been refined as technology made increased precision possible.

 

 

No. a 'Second' being the duration 1/86400 of Earth's rotation.

That's the old definition. 

 

As with the meter, technological advances have made greater precision possible.  We are now able to measure time down to around a tenth of a trillionth of a second.  The GPS system needs accuracy within a few billionths of a second.  The rotation of the Earth varies by more than that.  Interestingly, a redefinition of the second became a technological necessity. ..... but it is still based on 1/86400 of a day. 



#16 piasan

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Posted 17 August 2015 - 12:28 AM

I chose two links from Calypsi's list. No, they were not random selections.

sciencenews.org
.
.
This probably is a silly question. The two media ("paths") don't violate the requirement of vacuum? The issue is the constancy of the subject's speed within a vacuum.

math.ucr.edu
.

I am gratified as I always resist the notion of a "massless" entity. Yes, I know the photon at rest could have no mass. We all know that no one believes a stationary photon to exist, or rather, that one will be found.

I've looked at a couple of Calypsys' references.  Honestly, I don't think he reads them.   It is clear a proper response to his 9 citations will require a couple days and more than one post.

 

Try this one, it's really interesting ....

http://math.ucr.edu/...d_of_light.html

 

Among the things it says (emphasis Pi's):

....

The quantum theory of atoms tells us that these frequencies and wavelengths depend chiefly on the values of Planck's constant, the electronic charge, and the masses of the electron and nucleons, as well as on the speed of light.  By eliminating the dimensions of units from the parameters we can derive a few dimensionless quantities, such as the fine-structure constant and the electron-to-proton mass ratio.  These values are independent of the definition of the units, so it makes much more sense to ask whether these values change.  If they did change, it would not just be the speed of light which was affected.  All of chemistry depends on their values, and significant changes would alter the chemical and mechanical properties of all substances.  Furthermore, the speed of light itself would change by different amounts according to which definition of units was used.  In that case, it would make more sense to attribute the changes to variations in the charge on the electron or the particle masses than to changes in the speed of light.

In any case, there is good observational evidence to indicate that those parameters have not changed over most of the lifetime of the universe.....

 

Today, high energy physicists at CERN in Geneva and Fermilab in Chicago routinely accelerate particles to within a whisker of the speed of light.  Any dependence of the speed of light on inertial reference frames would have shown up long ago, unless it is very slight indeed.....

 

If general relativity didn't work, then the GPS satellite system would fail dismally at telling you where you are and what the time is. ....

 

In other words, his source clearly says "there is good observational evidence to indicate ... the speed of light .... has not changed over most of the lifetime of the universe.

 

I must thank Calypsis for providing a reference that supports my claims.


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#17 Schera Do

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Posted 17 August 2015 - 01:06 AM

The meter has been defined for years now as one 299,792,458th of a light second, a light-second being the distance light travels in a second in any inertial reference frame, and a second being 9,192,631,770 periods of the transition between the two levels of the ground state of a cesium 133 atom.
...

... No. a 'Second' being the duration 1/86400 of Earth's rotation.
 

... That's the old definition.
...

.
I was aware of that when I posted the reference to Earth's rotation.

I'm attempting to make people think a certain way about 'Time' and physical processes. The above are two examples.

#18 Calypsis4

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Posted 17 August 2015 - 06:23 AM

Schera Do

 

 

Don't count me in. I don't make any claim of knowing "the speed of light ... in very ancient times".

 

 

 

Yet you still believe in cosmic evolution anyway...and that our universe/world is billions of years old. So don't shy away from the charge.

 

Don't count me in. I've never had the opportunity to "admit" such a thing as I've never heard of that thing before reading the content at the links.

 

 

 

That list I provided is much longer than what I posted and I could have included several pages of those who don't believe the speed of light is a constant. .

 

Did you give the lists of examples so that we could learn of humans affecting the speed of light by "changing the nature of light" as described in at the sciencenews link? To wit:

 

 

 

IF man can do it, why would you  think that God could not?


A new experiment reveals that focusing or manipulating the structure of light pulses reduces their speed, ..." Did those scientists do a "God Almighty" imitation?

 

 

We imitate God by thinking and by acting. So?
 

Let's get one thing straight: It is your definition of God which permits "changing the nature of light at any time for any reason".

 

 

 

According to His infinite wisdom.
 



#19 piasan

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Posted 17 August 2015 - 11:22 PM

Rule 15: Elephant hurling, such as providing a barrage of citations to give the illusion of weighty evidence.

 

Let's deal with Calypsis' elephant hurling first....  if it is not elephant hurling, Calypsis should explain why he produces 4 references to one scientific paper and 2 references that are actually the same article.

 

Numbers added by Pi for reference purposes .....

 

So if you won't take heed to any of your comrades in accidentalism then it is little wonder that you won't believe us.

Item #4 was already addressed in post #16.  I will only add that Calypsis cites the source as saying: "we would then take c to be the upper limit on the speed of light" (Emphasis Pi's).  If, as the paper states "c" is an upper limit, this means the paper is of no use to YEC because YEC needs light to be faster, not slower.

 

 

 

Items #1, 7, 8, and 9 all reference the same paper which can be found here:  http://arxiv.org/ftp...1/1411.3987.pdf

Article 7 points out this research deals with the slowing of light .... which only means it takes longer for light to reach us.   But how much slowing are we talking about?   Article 7 says: "The slowing occurs at a rate of about one part in a hundred thousand."  That would mean light from galaxies 12 billion light years from Earth will actually need an extra 120,000 years to reach us.  This isn't exactly the kind of change that is going to help YEC.

 

 

 

Items #2 and 3 are actually the same article by Jesse Emspak published in two places.

As Calypsis points out the article says:  "The speed of light may not be constant ....  some scientists are exploring the possibility that this cosmic speed limit changes" (Highlight Pi's)

 

In the text of the article, we find the extent of these changes....

"....the amount of time the light takes to cross a given distance should vary as the square root of that distance, though the effect would be very tiny — on the order of 0.05 femtoseconds for every square meter of vacuum. A femtosecond is a millionth of a billionth of a second....."  (Pi comments, this is 50 billionths of a billionth)

 

We also find these results are far from accepted....

"... Jay Wacker, a particle physicist at the SLAC National Accelerator Laboratory, .... "It's a very interesting question [the speed of light]," he added, but the methods used in these papers are probably not sufficient to investigate it."

 

Setting aside the tentative and disputed nature of this variation, and evaluating its impact if it is true....

First:  This is a "variation" in the speed of light.  This means it may speed up or slow down so the difference would be plus or minus 50 billionths of a billionth of a second per meter.  Since this is a "variation," it will tend to cancel out over time.

Second:  Let's go to the extreme and stack  this variation all one way.  There is a time difference of 50 billionths of a billionth of a second per meter.  Light would need to travel 2x1016 meters to reach a difference of one second.  Using the current speed of light this would mean a difference of one second every 66.7 million seconds.  That's one second every 2.11 years.

 

The difference over 12 billion years would be 5.68 billion seconds or 180 years.

 

 

 

That leaves Wikipedia articles 5 and 6.  Aside from the fact this is the kind of discussion where the YEC here would disparage Wikipedia as a source.....

Here's the full paragraph for Calypsis' citation in article 5:

"Paul Davies and collaborators have suggested that it is in principle possible to disentangle which of the dimensionful constants (the elementary charge, Planck's constant, and the speed of light) of which the fine-structure constant is composed is responsible for the variation.[50] However, this has been disputed by others and is not generally accepted.[51][52]"  

 

I'm not sure exactly what Calypsis' point is, but something that is "suggested ... in principle possible" and is "disputed by others" doesn't seem a strong argument.  It is worth note this is the same Paul Davies who I pointed out had determined the speed of light when it left galaxies 12 billion light years from Earth was within 0.001% of the modern accepted value.  (Published in the journal Nature in August, 2002)

 

For article 6, the span of his ellipsis is virtually the entire article.  He will need to explain how jets travelling at less than the speed of light is a problem.

 

 

 

I think it has been shown that the "weighty evidence" provided by Calypsis "barrage of citations" isn't all that big a deal.  The first thing we found was that the nine were actually five. 

 

Of the five, one supported what I've been saying; one discussed the speed of light varying in the wrong direction; one discussed a possible variation that if it were stacked in one direction amounts to only a couple hundred years in twelve billion; and the two Wiki articles that don't seem to amount to much.

 

Notice, I did not "dis" the articles.  In fact, I will "take heed" to each and every one of them (except the Wiki articles)... I'm fine that light has varied in such a way it may have taken an additional 120,000 years to reach us from distant galaxies.  It doesn't bother me at all that light may be as much as 180 years faster over a period of 12 billion.  And I'm absolutely delighted that one of Calypsis' references is in full agreement with everything I've said.


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#20 piasan

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Posted 18 August 2015 - 11:10 AM

Did those scientists do a "God Almighty" imitation?

 

We imitate God by thinking and by acting. So?

I have two dogs, three cats, and a horse that "think and act."  Do they also imitate God when they do so?  Why is it different when a human does than when a dog or cat or horse does?







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