Light speed, c, experiment
By the end of the 19th century, experimental evidence appeared to show that all light moving through the vacuum of
space always has the same speed relative to every reference frame, body, light source, and light detector regardless
of the magnitudes and the directions of their velocities. Lacking any plausible explanation for this incredible
observed phenomenon, constant light speed, c, was made a law of physics. The theory of relativity is based on
this law and it seemed to confirm the law because the theory has been very useful and is consistent with a large body
of experimental evidence.
During the past two decades a theory that explains physical causes for constant light speed, c, has been developed
and investigated. This theory, known as the quantum medium view, (a.k.a. qm view) is based on the
premise that photons and all other forms of mass/energy are comprised of oscillations of a quantum
medium, qm, and that the oscillations move with a constant absolute speed, ca, through the qm
when not impeded directly by mass/energy in the qm (e.g. air) or indirectly by the effects of large
concentrations of mass/energy (e.g. stars) in the qm. (This absolute speed of light through the qm is
299 792 458 absolute meters per absolute second. This number is also the measured speed
of light, c, in virtual meters per virtual second, and to simplify the following calculations we will round this
number to 300 000 000.) The logical consequences of this premise are consistent with a wide variety of evidence,
and one of the consequences of a quantum medium through which all energy in the universe is propagated is the
illusion of constant light speed, c. The experiment proposed below is an additional test of the premise
and qm view.
If this premise is correct, then the speeds of light, cr, relative to any coordinate system or body
depend on the system's absolute velocity, va, (i.e. velocity through the qm) and the directions
of the photons' velocities through the qm relative to the direction of va. For example, for a system moving through the
qm at half the speed of light through the medium (e.g. the blue coordinate system in the figure below), the speeds
of photons relative to the system range from cr=.5 ca (when the system and the photons are moving in the
same direction through the qm) to cr=1.5 ca (when the system and the photons are moving in opposite
directions through the qm), as shown by the vectors in the figure.
The following experiment should be capable of determining if photons move with constant speed, c, relative to systems
moving with constant velocities near Earth or if the photons move with constant speed, ca, through a quantum medium
and therefore have speeds relative to the systems that depend on the systems' velocities through the qm. The
outcome of this simple experiment should help answer fundamental questions about the universe. It should affirm or deny
the existence of universal standards of time, distance, and mass, which are impossible if the law of constant light
speed, c, is a correct representation of nature.
Two atomic clocks, Cw and Ce, are aboard jet aircraft located
.0025 light-seconds, , (750 km) apart at an altitude of 15000 m
above MSL and moving eastward along a circle around Earth with a speed of .000002 c
(600 m/s or 2160 km/hr or Mach 1.76) relative to the ground below. At this
altitude the radio and/or laser ranging transmitters and receivers aboard the aircraft have good line-of-sight
communication with one another, and the instrumentation can accurately determine the distance between the clocks at
any particular times on the clocks. The clocks are essentially at rest relative to one another, and any minor change
in the distance between them (e.g. 20 m) should have no noticable effect on the outcome of the experiment.
Similarly, the absolute velocity, va, of the ground below the aircraft should not affect the experimental
results, and for convenience we will consider the ground at rest in the qm (the existence of which will be either
affirmed or ruled out by the experiment).
As the aircraft, clocks, and observers Ow and Oe move eastward, transponders on the aircraft allow accurate
determination of the travel time duration for round-trip radio and laser signals between the clocks and therefore
the distance between the clocks. For example, if the time for a round-trip radio or light signal between Cw and Ce
is .0050 s, then the time for a one-way signal must be .0025 s (if the signal speed in both
directions between Cw and Ce is c), and the distance between the clocks is
.0025 . Signals specifying the clock time when a radio or laser signal is sent
allow the clocks to be synchronized if the distance between the clocks is known. During the experiment, all
distance measuring, clock synchronizing, and reasoning by the observers will be based on the assumption of constant
light speed, c. The results of the experiment will indicate whether or not this assumption is correct.
Accordingly, as the clocks are moving eastward, clock Cw is set to zero seconds and simultaneously emits a signal
specifying this time when the signal left Cw. This is the first of two events shown in the following table of
events and times. The table shows the event in column 1, the time on clock Cw in column 2, and the
time on clock Ce in column 3. When the signal arrives at Ce (second event in table), Ce is set to the
tw=.000 000 000 s time plus the current distance in between the clocks.
This current distance is not crucial, but accurate measurment of the distance is very important.
We will assume accurate measurements and assume that the measured distance is the target distance,
.0025 . Therefore, clock Ce is automatically set to
.002 500 000 s (as shown in bottom-right box of table) and the observers believe
that this procedure must synchronize the clocks because the signal speed is c.
In the qm view, the clocks are virtually synchronized, which means they appear synchronized if one
assumes constant light speed, c. However, the clocks are absolutely asynchronized
because the speed of light from Cw to Ce is not the absolute speed of light, ca, because the CwCe reference frame is
moving eastward through the qm with an absolute velocity of va=.000002 ca. Therefore, the speed of
light from Cw to Ce is .999998 ca and the time for the light signal tw=.000 000 000 s
to move from Cw to Ce is (.0025/.999998) or .002 500 005 s or
5 ns longer than the time resulting from the constant light speed, c, assumption. Therefore, when the
tw=.000 000 000 s signal arrives at Ce, tw equals .002 500 005 s (shown
in column 2) and the virtual synchronization results in te = tw − .000 000 005 s
(second equation in bottom-right box), but the observers are not aware of the 5 ns asynchronization.
The two aircraft then make a coordinated U-turn beginning at the same time on their synchronized clocks
and finishing at the same time and maintaining more or less the same rate of turn and the same altitude and same
distance between the clocks until they are both heading westward. The change in direction may also involve a coordinated
deceleration before the turn (e.g. to 100 m/s) and acceleration after the turn. Because both clocks
experience more or less the same environment while making their turn (and are more or less at rest relative to one
another), there is no reason for one clock to advance noticeably more or less than the other. According to Table 1,
Cw started the U-turn 5 ns before Ce, but this will not have a significant effect on the experiment,
and after the U-turn Ce will continue to be 5 ns behind the time on Cw.
To check the synchronization of Cw and Ce after the U-turn, Cw sends another time-encoded signal, which
leaves Cw at time tw=900.000 000 000 s when te=899.999 999 995 s, as shown in
the first event in Table 2. When this signal arrives at Ce (last row in table), Oe and the instrumentation again
determine the time on Cw by allowing for the signal travel time, which is again
.0025 s because, for simplicity, we will again assume that the distance between the clocks is determined to
be .0025 . However, the speed of light from Cw to Ce is now 1.000002 ca
due to system CwCe's .000002 ca westward absolute velocity. Therefore, the travel time for the
tw=900.000 000 000 s signal is (.0025/1.000002) or .002499995 s, not
.0025 s as determined at Ce due to assuming light speed, c. This results in Oe and the instrumentation
at Ce mistakenly determining that Cw is reading 900.002 500 000 s when
te=900.002 499 990 s, which makes it appear that Ce is 10 ns behind Cw.
Table 3 shows that the same 10 ns asynchronization is also observed at clock Cw if Ce sends a signal at time
te=950.000 000 000 s when Cw is reading tw=950.000 000 005 s, as we know.
The travel time for the signal to reach Cw is (.0025/.999998) or
.002 500 005 s due to the westward .000002 c ground speed and resulting
.000002 ca westward absolute velocity of the CwCe system. Therefore, the arrival times on clocks Ce and Cw
are as shown, and the tw=950.002 500 010 s arrival time on Cw is 10 ns ahead of the
950.002 500 000 s time that the instrumentation and observer with Cw mistakenly determine
must be on Ce. Therefore, all observers and instrumentation in the CwCe system determine the same 10 ns
asynchronization caused by assuming constant light speed, c.
This 10 ns virtual asynchronization should be detectable. And if it is detected it will show that the
speeds of light were not constant during the experiment, and that the law of constant light speed, c, is not
correct. The results should lend additional support to the qm view because it is one more example of how this
view explains physical causes for the phenomena it predicts. We are confident that the predicted clock asynchronization
will occur because we know of no case among the wide variety of phenomena encompassed by the qm view where it does
not agree with and explain the observations logically and unambiguously.
The same real and virtual asynchronizations occur if the ground below CwCe has an absolute velocity, either aligned
with the CwCe system or at any angle to CwCe. The explanation would be more complex and would involve virtual and
absolute units of time and distance such as virtual and absolute seconds (s and sa), virtual and absolute
light-seconds ( and LS) and virtual and absolute meters (m and ma).
For example, if the ground is moving through the qm with a velocity of .01 ca in a direction 45 degrees
relative to a line from Cw to Ce, the real, absolute distance between the clocks will be shorter than
.0025 LS by 6.25E−8 LS or (18.75 ma), but the distance measured by the
instrumentation will continue to be .0025 , and the same 10 ns asynchronization
of the clocks will be observed.
Relativity theory explanation
According to relativity theory, an observer on the ground below Cw and Ce will observe (assuming adequate
instrumentation) that the clocks are asynchronized after the clocks are virtually synchronized in the CwCe
reference frame heading eastward. The ground observer (which we will designate Og) will observe that Ce is
5 ns behind the time on Cw. And throughout the remainder of the experiment as Cw and Ce make the U-turn and begin
heading west, Og will continue to observe that Ce is 5 ns behind the time on Cw. According to the qm view
and relativity theory there is no reason for clocks Ce or Cw to advance significantly more or less than the other
during the U-turn.
qm view explanation
The qm view shows that the observations of Og (that Ce is 5 ns behind the time on Cw throughout the experiment)
are correct because Og is at rest in the qm, which results in constant light speed in the ground reference frame
(as Og assumes). If Og had been in a reference frame moving eastward with absolute velocity va=.000002 ca, then Og
would have observed that clocks Cw and Ce were synchronized throughout the experiment. And if Og's reference frame had
been moving westward with absolute velocity va=.000002 ca, then Og would have observed that Ce is 10 ns
behind the time on Cw throughout the experiment because time (and hypothetical clocks) in Og's reference frame
would be asynchronized in the east-west direction by −5 ns/750 km of westward distance or by
+5 ns/750 km of eastward distance.
Therefore, the light-speed-c assumption results in the illusion that Og can change the asynchronization between Cw and
Ce by changing her velocity relative to the CwCe system. Is it reasonable for a theory to permit a distant observer to
influence the asynchronization of clocks by changing her velocity? In the qm view it is not possible for Og to
change the asynchronization of the clocks by changing her velocity. A ground observer who understands the qm view will
always observe the same asynchronization of the Cw and Ce throughout the experiment regardless of her velocity
because she will always allow for the changes in light speeds due to any changes in the velocity of her reference
frame. Is it not more plausible that Og cannot influence the asynchronization of the clocks and that the change in
synchronization that she observed is a virtual change?
Is light speed, c, an illusion?
The qm view shows that the illusions of changing asynchronization of clocks Cw and Ce during the experiment are
all caused by the constant light speed, c assumption of the observers and the changes in the speeds of light
between the clocks and the observers due to the changes in absolute velocity of the observers' reference frames. The
light-speed-c assumption by Ow and Oe created the illusion that the U-turn during the
experiment caused the clocks to gradually change from being synchronized when moving eastward to being 10 ns
asynchronized when moving westward. And the light-speed-c assumption of Og created the illusion that changing Og's
velocity can cause a change in the clock asynchronization.
The qm view explains these illusions and the illusion of constant light speed, c, in terms of logical
physical causes. It shows that the causes are the changes in the speeds at which energy quanta
move through a reference frame or through any physical system (e.g. CwCe) when the system's velocity is changed.
The fact that this view explains such a wide variety of phenomena is strong evidence that the view's explanation
for the experimental results is correct.
If observers Ow, Oe, and Og understood the qm view, they would all be in complete agreement on the times on Cw
and Ce and on their synchronization at the beginning and throughout the experiment. They would understand physical
causes for their observations and for the conflicting observations caused by assuming constant light speed, c. This
ability of all the observers to agree is additional evidence that the qm view is correct, and that the speed
of light is not constant in systems moving through the qm.
As Earth revolves around the sun we can observe periodic changes in the oscillation frequencies of the light from
distant sources and we can observe periodic changes in pulse rates of distant pulsars. These changes are exactly
explained by the periodic changes in the speeds of the radiation relative to Earth due to Earth's periodic changes
in velocity through the qm. This is further evidence that the speed of light is not a constant, c, relative to all
sources and observers.
Why conduct this experiment?
Although the outcome of this experiment can be predicted with confidence, teachers and students in many fields
of study would be interested in this test of the well-known law of light speed, c. The experiment would raise
questions about the possible causes of the experimental results. It would encourage people to consider carefully
the relativity theory and qm view explanations for the observations. It would increase awareness that
while relativity theory provides an accurate correlation between observed virtual phenomena and observed
virtual relative velocities between the observers and the virtual phenomena, it also obscures the real
phenomena responsible for the virtual phenomena and the virtual relative velocities.
Possibly it will become evident to many that relativity theory has been misleading and is fundamentally incorrect in
its assumption of constant light speed, c, and in its conclusions about the causes of relativistic phenomena
and gravity. Should this happen, then the experiment will have helped avoid continuing down a single path of
questionable thinking, and it would encourage people to be less certain that prevailing thinking must be correct.
It would be another reminder that a theory's agreement with experimental evidence and ability to predict phenomena
does not ensure that the theory is a correct representation of nature.
An objective of this light speed, c, experiment is to provide evidence that can help people compare the characteristics
of the qm view and relativity theory and determine which theory is the more plausible representation of nature. If
the qm view is determined to be more plausible, this will permit a variety of poorly understood phenomena
(e.g. inertia and gravity) to be understood in terms of logical physical causes. It will result in a more
understandable universe with universal standards of distance, time, and mass on which all observers can agree and that
are impossible with constant light speed, c. Therefore, good reasons exist for conducting this experiment.
Absolute times and distances are specified by clocks and distance measuring instruments at rest in the qm.
Absolute and virtual units are explained further on the
Equations page, the
Glossary page, and elsewhere on the qm view website.
The General Dynamics F-111 and the McDonnell Douglas F-15 Eagle can fly at Mach 2.5.
Knowing the measured distances to plus or minus .2 m would be sufficient. (The measured distances depend
on the refractive index of the air which is constantly changing and will vary over the 750 km distance. Therefore,
the measured distances will be virtual distances. However, we currently believe that ignoring the refractive index and
assuming constant light speed, c, will not significantly affect the determinations of the clock asynchronizations and
the experimental results.)
The "Introduction ..." and "Constant Light Speed, c, ..."
are a quick way to understand the light speed, c, illusion.
The philosophy of science
page on this website shows that the plausibility of any scientific theory depends
on various characteristics of the theory in addition to its ability to accurately