ReligionDiscuss General Theology, Religions and Denominations, God's Attributes, Predestination and Free Will, Dispensationalism, Eschatology, Philosophy, Origins, Archaeology, Science, World History and other such topics.
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The Church was not founded on the Bible. The Bible was assembled by the Church.
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August 30th, 2011, 02:36 PM
Quote:
Originally Posted by CabinetMaker
Yes, electromagnetic radiation propagates at the speed of light. No, a second is not defined based on the propagation speed of a photon, it is based on the number of osculations of the cesium atom.
...the speed of which, relies on electromagnetic radiation, which in turn travels at the speed of light.
Quote:
Originally Posted by CabinetMaker
Which presents certain problems since you don't have a definition of a second until you can accurately measure the time it takes a particle to travel a fixed distance. I hope you see the problem with trying to use a velocity as a standard definition of time.
Exactly. I do see that problem. But the speed of light defines time itself, nonetheless. Am I incorrect in saying the following?
Quote:
Originally Posted by glassjester
So yes, the speed of light does determine what a second is, because the movement of photons is, by definition, the speed of light. If light suddenly started moving faster, the caesium atom would transition between levels faster. That would make the second faster. If the speed of light suddenly slowed down, the caesium atom would transition between levels more slowly. That would make the second slower.
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The Church was not founded on the Bible. The Bible was assembled by the Church.
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August 30th, 2011, 03:29 PM
Quote:
Originally Posted by Desert Reign
Aw, shucks. And now we will never know if a 24 hour day really was a 24 hour day or not...
That's very true. God could have had the universe on fast forward during the creation week. A very real 24 hours could have passed in His intertial frame, while billions of years could have literally passed in our universe.
...the speed of which, relies on electromagnetic radiation, which in turn travels at the speed of light.
This is a deeply flawed statement. The concept of speed does not apply to frequency. Frequency is just a count of the number of times a cycle occurs in a given period of time. Electricity in the U.S. is generated at 60 cycles per second. If you have something that oscillates at a constant frequency it can be used to determine time. For instance, a pendulum swinging in a clock can be calibrated very precisely such that one cycle (right-to left- and back to right) is one second so the clock literally counts the number of times the pendulum swings. The springs and weights are required to overcome the loses in the system caused by the pendulum swinging in air. The effects of drag would eventually stop the pendulum if energy were not added to the system.
Through years of experiments across continents it has been determined that the oscillations in the cesium atom are constant. Since we now have a constant oscillator that does not require the addition of any additional energy to overcome loses, it can be used to establish a standard second. And that is what we have done. We have said that x number of oscillations of the cesium atom is one second. It is a definition.
Quote:
Originally Posted by glassjester
Exactly. I do see that problem. But the speed of light defines time itself, nonetheless.
But we can not determine what the speed of light is unless and until we have a definition of a second. We must first define the second in order to be able to measure the speed of light.
Quote:
Originally Posted by glassjester
Am I incorrect in saying the following?
Yes.
Galatians 5:22-23 (New International Version)
But the fruit of the Spirit is love, joy, peace, patience, kindness, goodness, faithfulness, gentleness and self-control. Against such things there is no law.
This is a deeply flawed statement. The concept of speed does not apply to frequency. Frequency is just a count of the number of times a cycle occurs in a given period of time. Electricity in the U.S. is generated at 60 cycles per second. If you have something that oscillates at a constant frequency it can be used to determine time. For instance, a pendulum swinging in a clock can be calibrated very precisely such that one cycle (right-to left- and back to right) is one second so the clock literally counts the number of times the pendulum swings. The springs and weights are required to overcome the loses in the system caused by the pendulum swinging in air. The effects of drag would eventually stop the pendulum if energy were not added to the system.
Through years of experiments across continents it has been determined that the oscillations in the cesium atom are constant. Since we now have a constant oscillator that does not require the addition of any additional energy to overcome loses, it can be used to establish a standard second. And that is what we have done. We have said that x number of oscillations of the cesium atom is one second. It is a definition.
But we can not determine what the speed of light is unless and until we have a definition of a second. We must first define the second in order to be able to measure the speed of light.
Yes.
But GJ has a point that it is not the frequency of oscillations of the caesium that determines the length of a second. The frequency is entirely circular. It is only the count that counts. One second is simply defined as the time it takes for the caesium to oscillate however many times it is (9 billion or so). Since that oscillation is dependent on the speed of light, we would never know if it had changed because we can only measure speed in terms of frequency. If the speed of light were to suddenly double, we would not be aware of it because however long it was, it would still be 9 billion oscillations, regardless of how long those oscillations took.
Where I think GJ is wrong is that he ignores the statistical implications of measurement. What we should understand is that measurements, though arbitrary, are correlated with each other. Thus we have a thousand clocks of different kinds all independently oscillating using different methods and the same length of time of one second is measured by all of them. It is that very statistical correlation that gives us the subjective impression of time being an absolute physical property of our experience. Understandable but not quite correct.
The reason why caesium clocks are deemed to be the most accurate is not because there is something we know that is particular to caesium but because when we compare a thousand caesium clocks (I exaggerate) with each other, all one thousand of them indicate the same time accurate to one second after millions of hours of running. Whereas when you compare a thousand pendulum clocks, they all disagree with each other by minutes after just one day. Even though the average of these clocks gives the same time as the caesium clocks, it means that a single pendulum clock is assumed to be less reliable. It is still possible that all the one thousand caesium clocks are uniformly wrong, that they might all be slowly lengthening the time instead of keeping it constant, however, there are still many other clocks that would disagree and such an event would have been discovered.
It is ultimately relative but the statistical implications are rock solid. The only possible fault of the argument - and the evidence - is if every single clock everywhere were somehow dependent on the same physical principle. For example, pendulum clocks rely on Earth gravity (itself varying over the Earth) but if it could be shown that Earth gravity was integrally related to the speed of caesium oscillations, then the same fundamental physical change would affect both the caesium clock and the pendulum ones. Thus you would never know if a change had taken place.
Total Misanthropy. Uncertain salvation. Luck of the draw. Irresistible damnation. Persecution of the saints.
Slogan/motto:
The Church was not founded on the Bible. The Bible was assembled by the Church.
Reputation:
August 30th, 2011, 08:17 PM
Quote:
Originally Posted by Desert Reign
The only possible fault of the argument - and the evidence - is if every single clock everywhere were somehow dependent on the same physical principle.
That's possible. It would likely be proven, if gravity was unified with the three other fundamental forces (string theory attempts this).
Quote:
Originally Posted by Desert Reign
For example, pendulum clocks rely on Earth gravity (itself varying over the Earth) but if it could be shown that Earth gravity was integrally related to the speed of caesium oscillations, then the same fundamental physical change would affect both the caesium clock and the pendulum ones. Thus you would never know if a change had taken place.
Interestingly enough, they seem to be related...
Quote:
Originally Posted by Wikipedia
"The speed of gravitational waves in the general theory of relativity is equal to the speed of light in vacuum, c."
The only possible fault of the argument - and the evidence - is if every single clock everywhere were somehow dependent on the same physical principle. For example, pendulum clocks rely on Earth gravity (itself varying over the Earth) but if it could be shown that Earth gravity was integrally related to the speed of caesium oscillations, then the same fundamental physical change would affect both the caesium clock and the pendulum ones. Thus you would never know if a change had taken place.
Not exactly. It's likely that a pendulum clock and a caesium clock are not affected to the same degree by a change in gravity. This is, afterall, why we use atomic clocks rather than pendulums to measure time accurately.
The problem with atomic clocks, as you correctly point out, is that we can never become aware of a change. This is because of the assumption of relativity and the possibility that what we are measuring in an atomic clock is of the same nature as light. So a gravitational variation produces a change in the atomic count, but we do not notice because:
We have defined it as unchanging, and
The only way to measure it is with other instruments that are affected in the same manner.
We could discover the variation in a caesium clock if we were to not assume relativity. We could take two synchronised atomic clocks and place them in different gravitational environments. We would very quickly find that gravity does affect caesium clocks. And we would most likely find that it affects them to a different degree than it does a pendulum.
But this far simpler and more reasonable way of conceptualising time, space and gravity is hidden by the assumption of the truth of relativity theory.
Originally Posted by CabinetMaker
You can also check a level against itself by setting it to level, drawing a line, flipping the level end for end and checking the line.
We would do well to respect the constancy (or consistency) that God built into the physical world. When Christians redefine constants to paper-over problems rather than solve them we, rightly, lose credibility in the eyes of a skeptical world and risk losing the ability to point constancy as an argument when it would suit our purposes. (Sauce for the goose is sauce for the gander)
The speed of light is constant. Time, on-the-other-hand, is relative. This is true, but the relative nature of time does not render time magical. Just because time can do something that light can’t do (manifest relativity) does not mean it can do all that you wish it could do. (Explain how light from distant stars could reach the earth if the earth is young). My statement is not meant to impugn young earth creationists, whom I respect for the courage of their convictions and the passion of their apologetics, but to extol them to shun intellectual laziness.
From whence came hydrogen?
"Not everyone who runs around in a red coat is a solider in King George’s army."
Respect for God is the begining of wisdom and pride comes before a fall.
But GJ has a point that it is not the frequency of oscillations of the caesium that determines the length of a second. The frequency is entirely circular. It is only the count that counts. One second is simply defined as the time it takes for the caesium to oscillate however many times it is (9 billion or so). Since that oscillation is dependent on the speed of light, we would never know if it had changed because we can only measure speed in terms of frequency. If the speed of light were to suddenly double, we would not be aware of it because however long it was, it would still be 9 billion oscillations, regardless of how long those oscillations took.
Where I think GJ is wrong is that he ignores the statistical implications of measurement. What we should understand is that measurements, though arbitrary, are correlated with each other. Thus we have a thousand clocks of different kinds all independently oscillating using different methods and the same length of time of one second is measured by all of them. It is that very statistical correlation that gives us the subjective impression of time being an absolute physical property of our experience. Understandable but not quite correct.
The reason why caesium clocks are deemed to be the most accurate is not because there is something we know that is particular to caesium but because when we compare a thousand caesium clocks (I exaggerate) with each other, all one thousand of them indicate the same time accurate to one second after millions of hours of running. Whereas when you compare a thousand pendulum clocks, they all disagree with each other by minutes after just one day. Even though the average of these clocks gives the same time as the caesium clocks, it means that a single pendulum clock is assumed to be less reliable. It is still possible that all the one thousand caesium clocks are uniformly wrong, that they might all be slowly lengthening the time instead of keeping it constant, however, there are still many other clocks that would disagree and such an event would have been discovered.
It is ultimately relative but the statistical implications are rock solid. The only possible fault of the argument - and the evidence - is if every single clock everywhere were somehow dependent on the same physical principle. For example, pendulum clocks rely on Earth gravity (itself varying over the Earth) but if it could be shown that Earth gravity was integrally related to the speed of caesium oscillations, then the same fundamental physical change would affect both the caesium clock and the pendulum ones. Thus you would never know if a change had taken place.
The mistake you and GJ make is assuming that the frequency of oscillation and the speed of light are somehow the same. This is not true. The frequency is just a count of how many times something happens in a given period of time. That is all. Wave propagation is something else completely and is not effected by frequency. We define one second as roughly 9 billion oscillations of a cesium atom under specific conditions. That is the ruler we use to determine other things such as the speed of light. We could define a second based on the speed of light but we don't, we define the second based on the oscillations of an atom. Would we know if the period of oscillations changed? Probably not. Would we care? Well if we don't know it changed, we wouldn't even know to care. Would our definition of a second hold up near a black hole? Yes. Because it is a definition. Would the second measured by a cesium clock near a black hole be the length of a second measured by a cesium clock on earth? A much more intriguing question.
Galatians 5:22-23 (New International Version)
But the fruit of the Spirit is love, joy, peace, patience, kindness, goodness, faithfulness, gentleness and self-control. Against such things there is no law.
Would the second measured by a cesium clock near a black hole be the length of a second measured by a cesium clock on earth? A much more intriguing question.
It's not intriguing at all! We know that different gravitational environments affect clocks. The measured amount of oscillations would not be the same.
It's not intriguing at all! We know that different gravitational environments affect clocks. The measured amount of oscillations would not be the same.
Yes, they would. The definition states we count 9-billion plus oscillations and that is 1 second. True by definition. The cesium atom would still oscillate near the black hole so we could count the oscillations and measure a second. What is interesting is trying to figure out how to compare the clock on earth with the clock near a black hole that is thousands of light years away. The signal between the two clocks that we would need to compare the seconds is also subject to the speed of light and that raises interesting questions about how information is passed.
Galatians 5:22-23 (New International Version)
But the fruit of the Spirit is love, joy, peace, patience, kindness, goodness, faithfulness, gentleness and self-control. Against such things there is no law.
Yes, they would. The definition states we count 9-billion plus oscillations and that is 1 second. True by definition.
You don't get any more arbitrary than that.
Quote:
The cesium atom would still oscillate near the black hole so we could count the oscillations and measure a second.
And yet the rate would not be the same as on Earth.
Quote:
What is interesting is trying to figure out how to compare the clock on earth with the clock near a black hole that is thousands of light years away. The signal between the two clocks that we would need to compare the seconds is also subject to the speed of light and that raises interesting questions about how information is passed.
Or you could just measure the effect of gravity, develop a conversion rate and formula and make a simple mathematical correction.
Its not totally arbitrary. We have an innate sense of what a second is and 9-billion plus oscillations is right. But yes, it is somewhat arbitrary.
Quote:
Originally Posted by Stripe
And yet the rate would not be the same as on Earth.
Since the rate is a definition, the rate would be the same. Once we count to 9-billion, one second has passed. True by definition.
Quote:
Originally Posted by Stripe
Or you could just measure the effect of gravity, develop a conversion rate and formula and make a simple mathematical correction.
But you could never test it to see if your correction factor was accurate. It would be based on untestable assumptions.
Galatians 5:22-23 (New International Version)
But the fruit of the Spirit is love, joy, peace, patience, kindness, goodness, faithfulness, gentleness and self-control. Against such things there is no law.
Your "catholic" is showing. - Sozo
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