# The Speed of Light Is Variable, Not Constant

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#### billslugg

"So, according to Einsteinian physics, the wavelength at the emitter is a function of the speed of the emitter,"

This is not true. The wavelength as seen by the emitter never changes. It is only the receiver who sees the wavelength change, this due to any relative motion between emitter and observer.

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Dragrath and Helio

#### Pentcho Valev

"So, according to Einsteinian physics, the wavelength at the emitter is a function of the speed of the emitter,"

This is not true. The wavelength as seen by the emitter never changes. It is only the receiver who sees the wavelength change, this due to any relative motion between emitter and observer.

All physics sources, without any exception, wrongly teach that the wavelength at the emitter does change with the speed of the emitter:

#### billslugg

You have confused your reference frames. The movie above is in the reference frame of the observers, this is why the wavelengths are changing. Do it again in the reference frame of the emitter and you will see the wavelengths do not change.

#### Pentcho Valev

You have confused your reference frames. The movie above is in the reference frame of the observers, this is why the wavelengths are changing. Do it again in the reference frame of the emitter and you will see the wavelengths do not change.

So the wavelength at the emitter does not change with the speed of the emitter. I agree with that. Or, if equidistant light pulses are emitted, the distance d between subsequent pulses, as seen by the emitter, is independent of the speed of the emitter. Correct. But then this distance d reaches the observer and becomes d', a different distance that depends on the speed of the emitter. Too preposterous, isn't it?

#### billslugg

The speed of light is invariant as seen in all reference frames. If there is relative motion between emitter and observer then the observed wavelength must change. This is why distant galaxies are red shifted.
We can see wavelength shifts in benchtop lab experiments via the Mossbauer effect. We see it in the frequency shift of GPS satellites. It's everywhere.

#### Pentcho Valev

The speed of light is invariant as seen in all reference frames. If there is relative motion between emitter and observer then the observed wavelength must change.

This is a valid argument:

Premise: The speed of light is invariant as seen in all reference frames.

Conclusion: If there is relative motion between emitter and observer then the observed wavelength must change.

The conclusion is false, so the premise is false as well (the combination "true premise, false conclusion" is forbidden in logic):

"Thus, the moving observer sees a wave possessing the same wavelength [...] but a different frequency [...] to that seen by the stationary observer." http://farside.ph.utexas.edu/teaching/315/Waveshtml/node41.html

"Vo is the velocity of an observer moving towards the source. This velocity is independent of the motion of the source. Hence, the velocity of waves relative to the observer is c + Vo. [...] The motion of an observer does not alter the wavelength. The increase in frequency is a result of the observer encountering more wavelengths in a given time." http://a-levelphysicstutor.com/wav-doppler.php

Max Planck Institute for Gravitational Physics: "You can see for yourself that, once more, there is a blue-shift - the pulse frequency measured at the receiver is somewhat higher than the frequency with which the pulses are sent out. This time, THE DISTANCES BETWEEN SUBSEQUENT PULSES ARE NOT AFFECTED, but still there is a frequency shift." https://www.einstein-online.info/en/spotlight/doppler/

"The wavelength is staying the same in this case."

#### billslugg

Your insistence that wavelength does not change for an observer is false. We see it happening in numerous experiments. No amount of your insistence that wavelength does not change makes it true.

#### Pentcho Valev

Brian Greene: "If you're moving relative to somebody else, time for you SLOWS DOWN."

It follows logically from Einstein's 1905 postulates that, if you're moving relative to somebody else, time for you SPEEDS UP. The postulates, true or false, entail that, if two clocks are in relative motion, either clock is slow as judged from the other clock's system. That is, any traveler who checks stationary clocks against his spaceship's clocks will find stationary clocks slow and his spaceship's clocks FAST. This also means that the traveler sees himself aging FASTER than stationary people.

Some (very few) Einsteinians obey logic and teach the valid deduction (but find different ways to confuse the reader):

"Twin A stays on the earth, while twin B flies quickly to a distant star and back...For the entire outward and return parts of the trip, B does observe A's clock running slow..." https://scholar.harvard.edu/files/david-morin/files/cmchap11.pdf

"At the same time, the twin in the spaceship considers himself to be the stationary twin, and therefore as he looks back towards Earth he sees his brother ageing more slowly than himself." http://topquark.hubpages.com/hub/Twin-Paradox

#### Pentcho Valev

Ethan Siegel: "Scientific Theories Never Die, Not Unless Scientists Choose To Let Them. When it comes to science, we like to think that we formulate hypotheses, test them, throw away the ones that fail to match, and continue testing the successful one until only the best ideas are left. But the truth is a lot muddier than that. The actual process of science involves tweaking your initial hypothesis over and over, trying to pull it in line with what we already know. [...] By the addition of enough extra free parameters, caveats, behaviors, or modifications to your theory, you can literally salvage any idea. As long as you're willing to tweak what you've come up with sufficiently, you can never rule anything out." https://www.forbes.com/sites/starts...die-not-unless-scientists-choose-to-let-them/

Sabine Hossenfelder (Bee): "The criticism you raise that there are lots of speculative models that have no known relevance for the description of nature has very little to do with string theory but is a general disease of the research area. Lots of theorists produce lots of models that have no chance of ever being tested or ruled out because that's how they earn a living. The smaller the probability of the model being ruled out in their lifetime, the better. It's basic economics. Survival of the 'fittest' resulting in the natural selection of invincible models that can forever be amended." http://www.math.columbia.edu/~woit/wordpress/?p=9375

Before 1915 theoretical physics was mainly DEDUCTIVE - you cannot tweak your theory unless the tweak is deducible from initial axioms (postulates). In 1915 Einstein replaced deduction with induction, and unlimited ad hoc tweaking, unrelated to any axioms, was allowed. Here Michel Janssen describes relentless tweaking performed again and again until "excellent agreement with observation" was reached:

#### Pentcho Valev

Deduction from clearly defined axioms (postulates) is the only reasonable method in theoretical physics:

"By a theory I shall mean the deductive closure of a set of theoretical postulates together with an appropriate set of auxiliary hypotheses; that is, everything that can be deduced from this set." W. H. Newton-Smith, THE RATIONALITY OF SCIENCE, p. 199 http://cdn.preterhuman.net/texts/thought_and_writing/philosophy/rationality of science.pdf

Einstein also seems to suggest that deduction, not induction, is the correct method:

Albert Einstein: "From a systematic theoretical point of view, we may imagine the process of evolution of an empirical science to be a continuous process of induction. Theories are evolved and are expressed in short compass as statements of a large number of individual observations in the form of empirical laws, from which the general laws can be ascertained by comparison. Regarded in this way, the development of a science bears some resemblance to the compilation of a classified catalogue. It is, as it were, a purely empirical enterprise. But this point of view by no means embraces the whole of the actual process ; for it slurs over the important part played by intuition and deductive thought in the development of an exact science. As soon as a science has emerged from its initial stages, theoretical advances are no longer achieved merely by a process of arrangement. Guided by empirical data, the investigator rather develops a system of thought which, in general, is built up logically from a small number of fundamental assumptions, the so-called axioms." https://www.marxists.org/reference/archive/einstein/works/1910s/relative/ap03.htm

The crucial question is: What if a theory in physics is not deductive (no clearly defined axioms; no explicit deductive paths leading from axioms to conclusions; ad hoc tweaking is allowed)?

Answer: Then the theory, e.g. Einstein's general relativity, is a not-even-wrong inductive concoction, essentially equivalent to curve fitting models:

"Curve fitting is the process of adjusting a mathematical function so that it fits as closely as possible to a given set of data points. The function can then be used as a mathematical model of the underlying data." https://www.coursehero.com/file/22708453/Lecture-10/

#### Pentcho Valev

Richard Feynman: "I want to emphasize that light comes in this form - particles. It is very important to know that light behaves like particles, especially for those of you who have gone to school, where you probably learned something about light behaving like waves. I'm telling you the way it does behave - like particles. You might say that it's just the photomultiplier that detects light as particles, but no, every instrument that has been designed to be sensitive enough to detect weak light has always ended up discovering the same thing: light is made of particles." https://www.amazon.com/QED-Strange-Theory-Light-Matter/dp/0691024170

If Feynman is correct, any wave-based concept of variation of the wavelength of light

is unrealistic. It makes sense to advance the following

Axiom: The wavelength of light is invariable.

and examine the logical consequences. First of all, given the formula (frequency)=(speed of light)/(wavelength), we conclude:

Any frequency shift entails (is caused by) a proportional speed-of-light shift.

It follows that the cosmological (Hubble) redshift is due to light gradually slowing down as it travels through intergalactic space, in a non-expanding universe. The idea that vacuum slows down light has been largely discussed but only in terms of quantum gravity. The implication that the Hubble redshift might be due to speed of light decrease is persistently ignored:

"...in some quantum-gravity models, the speed of photons in gamma rays would be affected by the grainy nature of spacetime..." https://fqxi.org/community/articles/display/255

Sabine Hossenfelder: "It's an old story: Quantum fluctuations of space-time might change the travel-time of light. Light of higher frequencies would be a little faster than that of lower frequencies. Or slower, depending on the sign of an unknown constant. Either way, the spectral colors of light would run apart, or 'disperse' as they say if they don't want you to understand what they say. Such quantum gravitational effects are miniscule, but added up over long distances they can become observable. Gamma ray bursts are therefore ideal to search for evidence of such an energy-dependent speed of light." http://backreaction.blogspot.fr/2017/01/what-burst-fresh-attempt-to-see-space.html

"Some physicists, however, suggest that there might be one other cosmic factor that could influence the speed of light: quantum vacuum fluctuation. This theory holds that so-called empty spaces in the Universe aren't actually empty - they're teeming with particles that are just constantly changing from existent to non-existent states. Quantum fluctuations, therefore, could slow down the speed of light." https://www.sciencealert.com/how-much-do-we-really-know-about-the-speed-of-light

For not so distant stars slow speed of light is manifested as cosmological (Hubble) redshift.

Light from very distant stars (very slow light) is manifested as what is called Cosmic Microwave Background (CMB).

Beyond a certain distance, the star light does not reach us at all.

The invisible "very slow light", and the light that does not reach us at all, explain the Olbers' paradox.

#### Harry Costas

Time is not a physical item and therefore cannot be changed.
But! Relativity explains how time can be relative in communication.
EMR can be affected by affecting the speed of the EMR.
Black holes have the ability to release matter at close to the speed of light eg M87, but also have the ability to pull in matter at the speed of light.

Trying to communicate in these cases can be misleading.

As for aging brothers.
They will age at the same time.
Time for communication may give you a sense of time young or time old.

#### Ed Stauffer

Think of an elastic stretched between 2 posts 10’ apart that is a straight line. Now let’s add some weights and some helium balloons so that you end up with a sawtooth pattern. How far is it from one post to the other if you follow the elastic.

Now think of the elastic as a photon, the weights as filaments/galactic clusters and the voids as helium balloons.

Is the universe expanding as fast as we think or is some of it just deformation of spacetime.

Also as the universe ages the is more and more water in space as time goes on. If light slows down in water does this affect redshift. As the light crosses the plateau’s that are voids anything that is on that plateau would be concentrated exactly on the surface of spacetime which is where the photons would be. the photons would also be aligned with the skin of spacetime itself.

#### billslugg

- Most of the motion of distant galaxies is due to the expansion of spacetime.
Some are receding at the speed of light and are becoming invisible.
- Up to a red shift of about .5, peculiar motion can account for several percent of the velocity.
- Added path length due to gravitational lensing can add a few years to the journey but is insignificant as compared to the 13 billion years some light takes to get here

Intergalactic space has so few atoms, about one per cubic meter, the interaction with any photon is insignificant.

#### billslugg

Each brother in the Twin Paradox views the other one as younger. This is possible since they are in different inertial reference frames.

Same thing goes for kinetic energy. Each brother sees the bullet hanging on a chain around his own neck as having no kinetic energy but sees the bullet hanging around his brother's neck as dangerously energetic.

In each case, if one frame of reference is accelerated to be the same as the other, the acceleration will cause all metrics to match.

#### Pentcho Valev

"Was Einstein wrong? Do we have to kill off the theory of space and time to make sense of the universe?" https://space.com/end-of-einstein-space-time

Of course you do, theoretical physicists (if it's not too late). First get rid of the underlying premise, Einstein's 1905 constant-speed-of-light nonsense:

"Einstein pulled all of these ideas together in his 1905 theory of special relativity, which postulated that the speed of light was a constant. For this to be true, space and time had to be combined into a single framework that conspired to keep light's speed the same for all observers." https://www.livescience.com/space-time.html

How about LIGO's gravitational waves (ripples in space-time)? Will you continue to worship them after killing off Einstein's space-time?

#### COLGeek

Moderator
You seem to not support Einstein's theories. Why the apparent "ax to grind"?

Lutfij

#### Classical Motion

Shoot an arrow thru a sheet of paper. X is the duration of passage. If paper is moving towards arrow, X will decrease. If paper moving away, X will increase.

The arrow remains constant speed and constant length. Only X changed.

Our present theory and narrative about light, is credited to Maxwell and Einstein.

Both these men worked with what they had. Or information they were given. Maxwell's equations work perfect in a circuit. It's works perfect with a connected EM field......because a connected EM field does indeed wave. And when you insert this wave dynamic into a dipole............AND...........get that same dynamic out of a receiving dipole.......WELL......what are most people going to assume? They are going to assume that the propagation is a waveform. A natural and logical deduction.

These men were not trying to deceive, they were trying to discover.

The real problem/mystery was not the constant speed. The real problem is the dynamic of that constant speed. Einstein's problem was fitting a continuous wave function(an unbroken length).......with constant speed.

If Einstein knew that light was intermittent lengths and durations, there would be no need for spacetime. Duty cycle, not frequency.

Local time and spacetime are only needed for continuous streams. Or continuous dynamics. But with duty cycle, instead of frequency, local time or spacetime is not needed. This changing duty cycle explains all of our light measurements without local time.

The phase change and the frequency change of a known emission, proves that we have omnipresent time and length(space). One frame. All events have the same frame. But observation and measurement have many frames. The event is true unto itself, but the observation and measurement vary greatly with angle and rate.

Science just doesn't realize this yet. So we have spacetime.....decades of spacetime with many lives and careers based upon it. Very hard to change. And institutions do not admit they are in error.

Spacetime is gona be here for awhile.

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#### COLGeek

Moderator
This thread and its collection of topics has gone on long enough. Closing now.

Thank you to all who contributed to the conversations.

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