[Nonsense]

Take if from me, unless you can, "bend it like Beckham", 'c' is a 'constant'.

[ThirdTerm]

The speed of light in a vacuum has been defined as exactly 299,792,458 meters/sec. It was standardized in 1983 for the sake of convenience. Scientists often make natural phenomenons easier to understand by cutting corners. If the speed of light is not constant, it would cause all kinds of problems in physics formulas which assume that the speed of light is unchangeable. It may actually vary slightly depending on circumstances.

Wide-bandwidth signal transmission with low latency is emerging as a key requirement in a number of applications, including the development of future exaflop-scale supercomputers, financial algorithmic trading and cloud computing1, 2, 3. Optical fibres provide unsurpassed transmission bandwidth, but light propagates 31% slower in a silica glass fibre than in vacuum, thus compromising latency. Air guidance in hollow-core fibres can reduce fibre latency very significantly. However, state-of-the-art technology cannot achieve the combined values of loss, bandwidth and mode-coupling characteristics required for high-capacity data transmission. Here, we report a fundamentally improved hollow-core photonic-bandgap fibre that provides a record combination of low loss (3.5 dB km−1) and wide bandwidth (160 nm), and use it to transmit 37 × 40 Gbit s−1 channels at a 1.54 µs km−1 faster speed than in a conventional fibre. This represents the first experimental demonstration of fibre-based wavelength division multiplexed data transmission at close to (99.7%) the speed of light in vacuum.
http://www.nature.com/nphoton/journal/v ... 13.45.html

[anasawad]

http://www.bbc.com/news/uk-scotland-gla ... t-30944584

The only way discovered to slow light is by manipulating it artificially. ^
Possible, but not what the argument is about.
The argument is about whether light changes speed in a medium, it doesn't. It ceasing to exist isn't change of speed.

In nature, speed of light was standardized because indeed all the observations and experements showed that its universal.

[Besoeker]

The argument is about whether light changes speed in a medium, it doesn't.

Then there would to specify c as being in a vacuum would there?

[anasawad]

@Besoeker
I already told you its clarified in explanatory pieces. Because while the speed of light is constant, its propagation and interaction with matter could lead to confusion in numbers when it shows different. So it must be clarified that this is the absolute speed of light when it does not interact with anything.
When it does interact, measurements of its speed would differ because the it would delayed by absorption as clearly showed in the sources i put and as i explained many times so far which you seem unable to understand.
When its obsorbed, it ceases to exist as light so it doesn't "slow" down, it simply no longer exists, which is why the delay.
Due to the fact that we can only measure the speed by measuring time taken for light to travel between 2 points, then we cant measure what exactly happens in the nanoseconds in between. So its clarified for people whom are not familiar with it.

You as the typical mark of your constant usage of circular reasoning fallacy in all your debates, ignored the sources, ignored the argument, and worse, did not even present an actual argument.

[Besoeker]

The argument is about whether light changes speed in a medium, it doesn't.

About 50 seconds into your link:

Light propagates more slowly when passing through materials like water or glass but goes back to its higher velocity as soon as it returns to free space again.

[anasawad]

@Besoeker
Or for god's sake. It says Propagates.
Don't tell me you don't even know what that means now when said in physics.

Physics The act or process of propagating, especially the process by which a disturbance, such as the motion of electromagnetic or sound waves, is transmitted through a medium such as air or water.

http://www.yourdictionary.com/propagation

i.e the interaction with the medium. And also mentioned and explained in the same piece i quoted from the source what it means.


EDIT:
In response to your edit.
Yes, because velocity is not speed. When you measure velocity in a medium its different than velocity in vacuum because it does not interact with anything in vacuum while it does interact with the medium if one exists.
Velocity is the distance divided by time in a given direction in a specific reference frame.
Velocity of light changes, speed of light does not.

[Besoeker]

@Besoeker
Or for god's sake. It says Propagates.
Don't tell me you don't even know what that means now when said in physics.

From the same link:

"back to its higher velocity"
So, according to that, the velocity changes.

[anasawad]

Yes. Velocity change. Speed of light does not.

This doesn't mean your point is right, nor does it mean mine is wrong. Because i did not say velocity doesn't change, i said the speed of light is constant because velocity in this matter is irrelevant.
Your point is that speed of light changes, which is wrong. Not naturally atleast.

EDIT:
BTW, congrats for moving for one post atleast from using circular reasoning fallacy into anther fallacy, irrelevant conclusion. Bravo
Even SJWs cant troll this hard.

[Decky]

Imagine you're laying bricks, when suddenly a broad walks by at the speed of light.....

She would be gone by the time the light has bounced into my eye and I had saw her. I wouldn't be able to shout anything at her.

[Nonsense]

She would be gone by the time the light has bounced into my eye and I had saw her. I wouldn't be able to shout anything at her.

Neither would she hear you, as the speed of sound is much slower than that of light.

[Besoeker]

Yes. Velocity change. Speed of light does not.

Remind me of what a dimensionless refractive index What is it a ratio of.
And why c specifies medium if the speed does not depend on the medium through which light passes?

[anasawad]

C specifies that it is in vacuum because its a meassurment of movement speed.
While velocity is used in when talking about mediums because its about speed of propagation.
Thus when you want to measure refraction index, you need to divide the speed of light over the speed of propagation in the given medium (i.e velocity)

Welcome to 7th grade physics.

Are you really going to keep using fallacies without presenting any argument or facts or anything in your debates ?

Anyways, 'm done here. This method you're using is intolerable and if you're not welling to stop trolling and using deceitfull methods then you're not worthy of the time spent on talking to you.

[Besoeker]

Thus when you want to measure refraction index, you need to divide the speed of light over [b]the speed of propagation in the given medium

So they are different.
Welcome to reality.

[anasawad]

'm not sure what kind of lousy 3rd world university that gave you an engineering degree.

[Besoeker]

:knife:
'm not sure what kind of lousy 3rd world university that gave you an engineering degree.

At least it allows me to post without the meaningless waffle.
And gave me a 50 year career desiging power electronics.

[anasawad]

Well, if it graduated an engineer who can not tell the difference between speed and velocity, can not tell the difference between movement and propagation. Can not understand the most basic scientific principles and thinks that light being absorbed and re-emitted by atoms means its slowed down or something. 'll say thats not a very good university.

And if it gave you a 50 year long career, then thats some very low standards they have in your country.

Though i will admit, if everything you have you learned from collage, then they taught you very well how to use logical fallacies. What, 4 you used so far in this argument alone ? Thats some advanced level of fallacy based arguments.

[B0ycey]

At least it allows me to post without the meaningless waffle.
And gave me a 50 year career desiging power electronics.

You have had quite the career. Thermodynamics, energy storage designing and installation and now designing power electronics. But you'll obviously be hanging up your boots soon as you're now in retirement. Plenty of time for trolling. And I'm sure your fit in another few jobs to do with engineering in retirement in the mean time.

[Besoeker]

You have had quite the career. Thermodynamics, energy storage designing and installation and now designing power electronics. But you'll obviously be hanging up your boots soon as you're now in retirement. Plenty of time for trolling. And I'm sure your fit in another few jobs to do with engineering in retirement in the mean time.

I have experience in the field of power electronics.
I have not claimed anything else. Please stick to the truth.

[Besoeker]

Well, if it graduated an engineer who can not tell the difference between speed and velocity, can not tell the difference between movement and propagation. Can not understand the most basic scientific principles and thinks that light being absorbed and re-emitted by atoms means its slowed down or something. 'll say thats not a very good university.

And if it gave you a 50 year long career, then thats some very low standards they have in your country.

Though i will admit, if everything you have you learned from collage, then they taught you very well how to use logical fallacies. What, 4 you used so far in this argument alone ? Thats some advanced level of fallacy based arguments.

What is the refraction index a ratio of? Since it is dimentionless, it must a a ratio of the same units. What is the unit?
It's a simple question and merits a direct answer. But I won't hold my breath.