Superluminal Motion, Slow Light in Vacuum, Crimestop

Feb 9, 2023
"For generations, physicists believed there is nothing faster than light moving through a vacuum - a speed of 186,000 miles per second. But in an experiment in Princeton, N.J., physicists sent a pulse of laser light through cesium vapor so quickly that it left the chamber before it had even finished entering. The pulse traveled 310 times the distance it would have covered if the chamber had contained a vacuum. Researchers say it is the most convincing demonstration yet that the speed of light - supposedly an ironclad rule of nature - can be pushed beyond known boundaries, at least under certain laboratory circumstances...The results of the work by Wang, Alexander Kuzmich and Arthur Dogariu were published in Thursday's issue of the journal Nature."

"The speed of light is a limit, not a constant - that's what researchers in Glasgow, Scotland, say. A group of them just proved that light can be slowed down, permanently..."But once that pattern has been imposed - even now the light is no longer in the mask, it's just propagating in free space - the speed is still slow," Padgett added."

"Glasgow researchers slow the speed of light"

George Orwell: "Crimestop means the faculty of stopping short, as though by instinct, at the threshold of any dangerous thought. It includes the power of not grasping analogies, of failing to perceive logical errors, of misunderstanding the simplest arguments if they are inimical to Ingsoc, and of being bored or repelled by any train of thought which is capable of leading in a heretical direction. Crimestop, in short, means protective stupidity."
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The speed of light may be manipulated depending on the medium that it is transmitted through.

Screenshot 2023-03-22 at 18.47.10.png

The speed of light is decreased when travels through transparent media such as air, water, glass etc. The ratio by which the speed of light is decreased is called the refractive index of the medium and is always greater than one.

The light travels at maximum velocity in a vacuum. The vacuum has less refractive index than Air. Air has a refractive index of 1.003.

The speed of light is actually higher when light passes through cesium.

These results are not brand new, but have been examined since 2000 or earlier.

In the view of General Relativity light travels on a geodesic; there should be no surprise if some geodesics are shorter than others. There can be more geodesics that connect two points. But the speed of light will still be c during the time of the travel, only that the road will be shorter. This is if truly we talk about shorter geodesics and not about the effect that

Also, "In 1967, acting on Einstein's proof that the speed of light is the most constant dimension in the universe, the International System of Units used two specific wave counts from an emission spectrum of caesium-133 to co-define the second and the metre. Since then, caesium has been widely used in highly accurate atomic clocks."

In Einstein's view the geodesic is not just the result of gravity but of the non-symmetric field, the unified field of gravity and of electromagnetism.

The speed of light in a gas is very close to, but slightly less than, the speed of light in a vacuum. Depending on how you define "speed" (group velocity, phase velocity,...), it is possible to get materials in which the speed of light is greater than in vacuum. However, there is no way that would happen in a gas made out of neutral atoms. None of this has any implications for relativity.

Constancy of c in relativity is the constancy of the speed of light in vacuum. Actually, it would have consequences for relativity if a signal could propagate at >c in a medium. There would then be frames of reference in which the signal was received before it was transmitted, leading to problems with causality. But cases like this one don't actually allow signals to propagate at >c. This is why it's important to make distinctions like group velocity versus phase velocity.


Light Speed(s)

1 Let be the angular velocity and k the wavenumber , then the phase velocity Vf is
defined as
Vf=π/k (1)
The group velocity is the velocity with which energy propagates and is defined by
Vg= δπ/δk (2)
2. The case of light
If a wave satisfies the dispersion relation then:
π(k)= k2c2 +const (3)
Expression (3) is exactly the case for light. From (1), (2) and (3) we obtain
Vg*Vf=c2 (4)
In (4) Vf or Vg can be greater than c or even negative. Though Vf or Vg may exceed c no energy or information actually travels faster than c. Experiments showing group velocities greater than c include that of Wang et al. , who produced a laser pulse in atomic cesium gas with Vg between (-310+5)c and (-310-5)c.
Vf is in the range –c/305 to –c/315.

A Wave, in simple words, can be described as a mere disturbance along any plane surface. For instance, consider an ocean, where the Waves move along the ocean surface from one place to another. The crest of a Wave moves at intervals and therefore travels a specific distance over a specific time period. In this chapter, you are dealing with Phase and Group Velocity, which are properties of Waves. When a Wave moves in Groups, the speed or Velocity at which it moves is known as the Group Velocity.

What is Group Velocity?
The Group Velocity of a Wave is defined as the Velocity at which an entire envelope of Waves moves through a medium. A most common Example, in this case, can be that of throwing stones in a water body which causes multiple Waves on the surface of water.

On throwing the stone, a ripple is created around the point where the stone drops. The ripple is formed of small Wavelets which propagate away from the dropping point in multiple directions. Here, a Wavelet having the shortest Wavelength propagates faster than others.

However, to understand what Group Velocity is, you should also have an idea of simple harmonic motion too. This will help you in understanding the concepts better and in a more natural way.

What is Phase Velocity?
Considering the fact that a Wave consists of two significant parts crest and trough, its Phase Velocity is also dependent on the same.

It is the Velocity at which a specific component of a Wave, say crest, propagates in space.

This feature or Velocity is directly dependent on the time period and Wavelength. Alongside, you should also be clear about the relation between Phase Velocity and Group Velocity.

  1. Feynman, Leighton and Sands (vol1) Addison-Wesley
  2. Wang, L. J.; Kuzmich, A.; and Dogariu, A. "Gain-Assisted Superluminal Light
    Propagation." Nature 406, 277-279, 2000.

Not everyone is convinced the NEC scientists did what they claim.

Aephraim Steinberg, a physicist at the University of Toronto, said the light particles coming out of the cesium chamber may not have been the same ones that entered, so he questions whether the speed of light was broken. Still, the work is important, he said: ''The interesting thing is how did they manage to produce light that looks exactly like something that didn't get there yet?'' The achievement has no practical application right now but experiments like this have generated considerable excitement in the small international community of theoretical and optical physicists.

''This is a breakthrough in the sense that people have thought that was impossible,'' said Raymond Chiao, a physicist at the University of California at Berkeley who was not involved in the work. Chiao has performed similar experiments using electric fields. In the latest experiment, researchers at NEC developed a device that fired a laser pulse into a glass chamber filled with a vapour of cesium atoms. The researchers said the device is sort of a light amplifier that can push the pulse ahead.

Previously, experiments have been done in which light also appeared to achieve such so-called superluminal speeds but the light was distorted, raising doubts as to whether scientists had really accomplished such a feat. The laser pulse in the NEC experiment exits the chamber with almost exactly the same shape but with less intensity, Wang said. The pulse may look like a straight beam but actually behaves like waves of light particles. The light can leave the chamber before it has finished entering because the cesium atoms trade energy with the leading edge of the waves as they pass through. This produces an almost identical light pulse that exits the chamber and travels about 18 metres before the main part of the laser pulse finishes entering the chamber, Wang said.

Wang said the effect is possible only because light has no mass; the same thing cannot be done with physical objects. The Princeton experiment and others like it test the limits of the theory of relativity Albert Einstein developed nearly a century ago. The special theory of relativity states the speed of particles of light in a vacuum, such as outer space, is the only absolute measurement in the universe.

Ultimately, the work may contribute to the development of faster computers that carry information in light particles.


The speed of everything else - rockets or inchworms - is relative to the observer, Einstein and others explained. In everyday circumstances, an object cannot travel faster than light. The Princeton experiment and others change these circumstances by using devices such as the cesium chamber, rather than a vacuum.

Feb 9, 2023
A large number of experiments have shown that superluminal motion is possible. However the scientific community is unable to react adequately because Einsteinians bombard it with idiotic and confusing explanations, often involving "group velocity" and "phase velocity". Experimentalists are forced to include such explanations in their articles - otherwise there would be no publication. Sometimes "group velocity" and "phase velocity" turn out to be insufficiently confusing and Einsteinians resort to the ultimate weapon - the preposterous "speed of information". This speed confuses and paralyses any critic or heretic:

Robert W. Boyd, Daniel J. Gauthier, Controlling the Velocity of Light Pulses: "So why do laboratory results of fast light not necessitate the superluminal transfer of information? It is believed that the explanation lies in the distinction between Vg [group velocity] and the information velocity. The group velocity can take on any value. However, the information velocity can never exceed c and, according to many models, is always equal to c."

LIGO fakers: "The fact that the speed of gravitational waves is equal to the speed of electromagnetic waves is simply because they both travel at the speed of information."

If it were not for the confusing environment created by the Einstein Cult, superluminal motion would be regarded as commonplace. Just a few examples (note preposterous explanations of why Divine Albert's Divine Theory survives):

Nature 406, 277-279 (20 July 2000): "...a light pulse propagating through the atomic vapour cell appears at the exit side so much earlier than if it had propagated the same distance in a vacuum that the peak of the pulse appears to leave the cell before entering it."

"The speed at which light travels through a vacuum, about 186,000 miles per second, is enshrined in physics lore as a universal speed limit. Nothing can travel faster than that speed, according to freshman textbooks and conversation at sophisticated wine bars; if anything could, Einstein's theory of relativity would crumble, and theoretical physics would fall into disarray. Two new experiments have demonstrated how flexible or misleading that comfortable wisdom can be in the right circumstances. Using a combination of atomic and electromagnetic effects, researchers have produced light beams in the laboratory that appear to travel much faster than the normal speed of light. Einstein's theory survives, physicists say, but the results of the experiments, they agree, are mind-bending. In the most striking of the new experiments a pulse of light that passes through a transparent chamber filled with specially prepared cesium gas appears to be pushed to speeds of 300 times the normal speed of light. That is so fast that, under these peculiar circumstances, the main part of the pulse exits the chamber even before it enters...But Einstein's theory, and at least a shred of common sense, seem to survive, the physicists explain, because the effect could never be used to signal back in time to change the past and, in the example, avert the accident."

"Light hits near infinite speed in silver-coated glass. A nano-sized bar of glass encased in silver allows visible light to pass through at near infinite speed. The technique may spur advances in optical computing...In a vacuum the refractive index is 1, and the speed of light cannot break Einstein's universal limit of 300,000 kilometres per second. Normal materials have positive indexes, and they transmit at the speed of light in a vacuum divided by their refractive index. Ordinary glass, for instance, has an index of about 1.5, so light moves through it at about 200,000 kilometres per second. The new material contains a nano-scale structure that guides light waves through the metal-coated glass. It is the first with a refractive index below 0.1, which means that light passes through it at almost infinite speed, says Albert Polman at the FOM Institute AMOLF in Amsterdam, the Netherlands. But the speed of light has not, technically, been broken. The wave is moving quickly, but its "group velocity" the speed at which information is travelling is near zero."

"Speed of light broken with basic lab kit. Electric signals can be transmitted at least four times faster than the speed of light using only basic equipment that would be found in virtually any college science department. Scientists have sent light signals at faster-than-light speeds over the distances of a few metres for the last two decades - but only with the aid of complicated, expensive equipment. Now physicists at Middle Tennessee State University have broken that speed limit over distances of nearly 120 metres, using off-the-shelf equipment costing just $500...While the peak moves faster than light speed, the total energy of the pulse does not. This means Einstein's relativity is preserved, so do not expect super-fast starships or time machines anytime soon."

"Researchers at the University of Ottawa observed that twisted light in a vacuum travels slower than the universal physical constant established as the speed of light by Einstein's theory of relativity...In The Optical Society's journal for high impact research, Optica, the researchers report that twisted light pulses in a vacuum travel up to 0.1 percent slower than the speed of light, which is 299,792,458 meters per second...If it's possible to slow the speed of light by altering its structure, it may also be possible to speed up light. The researchers are now planning to use FROG to measure other types of structured light that their calculations have predicted may travel around 1 femtosecond faster than the speed of light in a vacuum."

"Light Pulses That Travel Faster Than Light Created...The technique developed at NIST is called four-wave mixing, and it works by altering some parts of each individual light pulse. This makes the light move forward faster than it normally would when traveling through a vacuum...The physicists explain that the new research does not violate Albert Einstein's theory on general relativity - which states that the speed of light in a vacuum is the fastest achievable in the Universe. They say that a sort of loophole exists in this theory. By careful tuning of the light source and advanced calculations, it is possible to nudge portions of the light pulses so that they arrive at their destination ahead or behind the main pulse...With four-wave mixing, the NIST investigators produced laser pulses that arrived at their destination a full 50 nanoseconds faster than photons traveling through a vacuum."

"Light that travels... faster than light!...This is exactly what the EPFL team has demonstrated. Using their Stimulated Brillouin Scattering (SBS) method, the group was able to slow a light signal down by a factor of 3.6, creating a sort of temporary "optical memory." They were also able to create extreme conditions in which the light signal travelled faster than 300 million meters a second. And even though this seems to violate all sorts of cherished physical assumptions, Einstein needn't move over - relativity isn't called into question, because only a portion of the signal is affected."

"Recent experiments show that particles should be able to go faster than light"

"Nimtz and others argue that an analysis of signal shape and frequency spectrum has evidenced that a superluminal signal velocity has been measured and that tunneling is the one and only observed violation of special relativity. However - in contradiction to their opponents - they explicitly point out that this does not lead to a violation of primitive causality."ünter_Nimtz
Feb 9, 2023
"Researchers at the University of Ottawa observed that twisted light in a vacuum travels slower than the universal physical constant established as the speed of light by Einstein’s theory of relativity...If it’s possible to slow the speed of light by altering its structure, it may also be possible to speed up light. The researchers are now planning to use FROG to measure other types of structured light that their calculations have predicted may travel around 1 femtosecond faster than the speed of light in a vacuum."

Not so fast, researchers at the University of Ottawa! Slow light in a vacuum is a sin but Einsteinians may still forgive you. However "faster than the speed of light in a vacuum" is absolutely unforgivable. Remember what happened to poor OPERA scientists:

"Two leaders of the OPERA collaboration, which stunned the world in September when it announced data suggesting that neutrinos could travel faster than the speed of light, have stepped down. The resignation of Antonio Ereditato as spokesperson and Dario Autiero as physics coordinator of the study followed a vote of no confidence, held yesterday by leaders of the individual groups within the collaboration, according to a source at OPERA who asked not to be identified."