I have some comments on Newton/Lisle's starlight article
(http://www.answersingenesis.org/tj/v15/i1/starlight.asp), and a few
questions (in my first paragraphs below) from someone who understands the
theory of relativity better than I. Quotes from the article are in < >
brackets.
<It may seem bizarre that light should travel at a speed depending on its
angle relative to an observer. But is this any stranger than the canonical
idea of light being constant regardless of the motion of the observer?
Either way, light seems to 'know' how the observer is moving and adjusts
accordingly. >
JPT: This makes no sense whatsoever. In one case, light travels at an
absolute speed, independent of observers, based on physical property. This
is not strange at all! What he seems to be saying is that all observers
measure the speed of light as being the same, regardless of their speed or
direction of travel.
JPT: I have a question about this: Let's say there's an observer traveling
at 1/4 the speed of light, and they observe a beam of light passing by.
Will they (from their perspective) measure the light as traveling at 1,079
million km/hr, the same as a stationary observer? Is this really accurate
according to the theory of relativity? If so, then his statement might have
some merit, because this does seem to be a bit of a bizarre property of
light to be observed at the same speed regardless of the speed of the
observer.
JPT: However, probably not, because to measure the speed of light, we would
measure its travel over a distance and a certain period of time. Onboard
the hypothetical spaceship, both distance and time dilate to smaller values,
so the ratio of distance/time might be the same as for a stationary observer
to yield the same "absolute" speed of light. In this case, it is not
necessarily a property of light "knowing" about the observer, but the
perspective of the observer themselves (relative distance and relative time)
which changes, and still yields the same observed speed of light. Is this
more or less a correct statement?
JPT: Another question: If light moved at infinite speed toward an observer,
wouldn't there be some sort of red shift (or blue shift) or other effects on
the light which should be observable?
<A change in the speed of light would have profound consequences for the
rest of physics, and these are not observed. Others have proposed that
gravitational time-dilation may cause different parts of the universe to age
at different rates (so the universe really could be billions of years old
from some points of view, but only thousands of years old as measured by an
observer on Earth).1 This theory is ingenious, and the premise is sound. But
the model may have fatal quantitative problems, and may fail to produce the
degree of time-dilation required for starlight billions of light years away
to reach Earth in 6,000 years.>
JPT: It sounds to me like Newton/Lisle is proposing a change to the speed of
light, for which he admits there is no observation confirming the "profound
consequences".
<In other words, had there been an observer standing on Earth on Day 4 of
the Creation Week, he or she would have seen the stars being created on that
day. >
JPT: So we have to modify the Biblical text to postulate a non-existing
"appearance of human observer" to go along with our "appearance of age".
And this is supposed to be true to the Bible, which says only that God was
the observer on the 4th day?
<It is possible to define a variable t which records when we detect a given
event. If t is a legitimate time coordinate (if observed time is 'real'),
then events happen when we see them happen. In this view, light travels
instantaneously from stars to Earth (though light travels at different
speeds in other directions). But keep in mind that this is due to the way in
which we have defined time, not the way that light 'actually' travels. >
JPT: Here, Newton conflates "observed time" with "calculated time," and
creates by fiat (ex nihlio) an infinite speed of light, so he can state that
the two times are identical. Since there is (according to him) no way to
observe the difference, I guess you can make up whatever science you want.
JPT: His section titled "Relativity and Time" seems to have no relevance to
the question at hand, where he brings in the hypothetical observer passing
by the earth at a high rate of speed and observing some event
simultaneously. The question of starlight is not dealing with one observer
going at high rates of speed compared to one on earth, but rather the
observation of astronomical events from the earth. This seems to me an
effort to impress the lay reader about the complexity of the theory of
relativity, and make them mentally tune out the details so they will accept
whatever bizarre twist of science (or pseudo-science) he might propose next.
<This [special relativity's feature of time dilation] may seem bizarre to
those unfamiliar with Relativity, but it is a well-tested principle of
nature. >
JPT: If this is so, why does he later brush aside all the "well tested"
science on time dilation and the measurement of the speed of light by
claiming that they have no way of synchronizing clocks to measure the speed
of light? How could you test time dilation without synchronized clocks?
<We can easily synchronize them since they are both in the same place. We
then move one clock to the end of the hallway-knowing that it has already
been synchronized. But there is again a problem. Einstein's Relativity tells
us that the time measured by an object is affected by that object's motion.
In other words, the very act of moving the clock down the hall has caused it
to become unsynchronized! >
JPT: This is pure fabrication - relativity only affects the time on a clock
if it is moving close to the speed of light. Assuming Jason Lisle doesn't
run anywhere close to that speed, there is no problem of having the distant
clock synchronized once he runs down the hall with it.
<But even if it could be demonstrated that Einstein synchronization is the
only fundamentally 'correct' convention (implying that light propagation
really must be isotropic), observed time is still a valid phenomenological
quantity.>
JPT: Here he fudges, just in case some serious scientist spends enough time
to take him to task on his assertions, by falling back on phenomenological
language used in scripture. However, if he ever had to admit that science
might be right about the speed of light, his whole theory would have
collapsed, and the phenomenological argument would prove inadequate for his
purpose. Hopefully by then he will have concocted a more elaborate theory
to fall back on.
<To be clear, both calculated and observed time conventions are perfectly
legitimate from a theoretical point of view. (In fact, there are an infinite
number of valid synchrony conventions.)>
JPT: There are an infinite theoretical mathematical systems other than the
finite math that we learned in school. But that doesn't necessarily mean
they are practical to everyday observations.
<we have only recently known the speed of light and the distance to the
stars with any accuracy.>
JPT: Amazingly, he admits that we have measured the speed of light and
distance to the stars with accuracy!
<About 4.3 years before Earth is created, 'the beginning' occurs for the
space near Alpha Centauri. Four days later Alpha Centauri is created.
Finally the Earth is created, but the starlight has not yet reached Earth;
God provides a temporary light source. Four days later, God creates the Sun,
the planets and the moon.>
JPT: This appears to contradict his earlier argument that starlight travels
at infinite speed, although in his theoretical world he is dealing with
"calculated time" here. This postulate has now created a new definition of
what the Day 1 creation meant. Here, he is saying that on Day 1, space is
created for the Alpha Centauri solar system to exist in, and later space is
created in which our solar system and earth could exist in. But he has
ignored some clear statements from Genesis, such as "And the Spirit of God
moved upon the face of the waters" at the beginning of the first day.
<The only similarity-this idea of 'billions of years'-merely comes from the
way in which we have chosen to define time, and does not reflect the
duration of any actual process.>
JPT: There you have it -- appearance of age. However, this formulation of
describing how starlight could appear on Day 4 to a (yet uncreated) human
observer, ignores all the other evidence for an old earth, such as annual
sediments, coral reef formation, etc. Here they have to come up with
different methods of apparent age which don't depend on the theory of
relativity, but on other selective and creative use of scientific facts.
Jon Tandy
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Received on Thu Jul 6 16:23:58 2006
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