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  4. What determines the speed of light?
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What determines the speed of light?

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Offline katieHaylor (OP)

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What determines the speed of light?
« on: 03/11/2017 12:25:07 »
Jerry asks:

Why does light travel at  186000 miles per second? I can see after reading comments no one knows 100 per cent for sure. I believe that if we figure out that answer we can then figure out how to reach that speed and beyond.

What do you think?
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Offline Zer0

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Re: What determines the speed of light?
« Reply #1 on: 03/11/2017 21:05:28 »
Quote from: katieHaylor on 03/11/2017 12:25:07
Jerry asks:

(1)Why does light travel at  186000 miles per second? (2)I can see after reading comments no one knows 100 per cent for sure. (3)I believe that if we figure out that answer we can then figure out how to reach that speed and beyond.

(4)What do you think?

Hello Jerry ☺

(1) Light travels at an approximate Speed of 186,282.397 miles per second ONLY in a Vacuum.

The Speed of Light can vary/change with respect to the Refraction Index of the Medium through which it is passing/travelling.

The higher the index of refraction is, the slower the speed of light is. The indexes of refraction for diamond, air and glass are, respectively, 2.42, 1.00, and approximately 1.50, depending upon the composition of the glass. Light travels slowest in diamond.

http://abcnews.go.com/Technology/story?id=99111&page=1
https://www.sciencedaily.com/releases/2013/08/130806111151.htm
https://www.livescience.com/396-scientists-mess-speed-light.html

(if anyone could Please take a look at the information provided in the links above n kindly verify the authenticity of the mentioned scientific claims I would be most grateful) 🙏
*(Please Note - HTTP VS HTTPS. Hyper Text Transfer Protocol Secure (HTTPS) is the secure version of HTTP, the protocol over which data is sent between your browser and the website that you are connected to. The 'S' at the end of HTTPS stands for 'Secure'. It means all communications between your browser and the website are encrypted.)* 😎

Scientists have long known that the speed of light can be slowed slightly as it travels through materials such as water or glass. However, it has generally been thought impossible for particles of light, known as photons, to be slowed as they travel through free space, unimpeded by interactions with any materials.
(free space is mostly considered a void empty vacuum but it might also constitute to be a hypothetical medium) 👼

(2) Not sure what comments you read and where so can't really comment on that hence no comments. 😜

(3) Conclusion - Yes it is Very Important and of Utmost Necessity that we Know the Actual reason as to why Light travels at an approximate speed in a vacuum, why not slower or faster, then just then maybe we could use that information/knowledge n apply it to design faster than light telecommunications.
Just like if we could figure out why Gravity inherits the quality of attraction n not repel, maybe after understanding it completely we could design antigravity transportation vehicles.
(its imperative to understand that we have just only begun ploughing the field of Quantum Mechanics n sowing all classical fundamental questions, Hopefully we shall achieve theoretically satisfactory answers in the coming future and reap the sweet fruits of universal knowledge) 🍎


(4) All Data collected/presented and Statements/Claims made were obtained from a never ending vast Electronic Ocean of Knowledge popularly known as thee Internet or the WorldWideWeb. 🌐
« Last Edit: 03/11/2017 21:26:22 by Zer0 »
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Offline evan_au

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Re: What determines the speed of light?
« Reply #2 on: 03/11/2017 21:27:30 »
In Maxwell's classical equations for electromagnetism, the speed of light is:
c = 1/SQRT(ε0×μ0)
Where:
- c is the speed of light in a vacuum
- ε0 is the permeability of a vacuum (effectively its capacitance, if you put it near two wires)
- μ0 is the permittivity of a vacuum (effectively its inductance, if you put it near a coil of wire)

There are many materials that have higher ε & μ than a vacuum (ie the speed of light is lower than c), but we have never found anything where these values are lower than a vacuum (ie the speed of light would be higher than c).

The ratio of the speed of light in a vacuum to the speed of light in a vacuum is the refractive index.
- A medium where the speed of light was > c would have a refractive index between 0 and 1.
- There are "metamaterials" where the refractive index is negative (over a narrow range of frequencies), but we have not seen these materials taking off into interstellar space!

See: https://en.wikipedia.org/wiki/Negative-index_metamaterial#Experimental_verification_of_a_negative_index_of_refraction
« Last Edit: 04/11/2017 10:37:13 by evan_au »
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Offline Bill S

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Re: What determines the speed of light?
« Reply #3 on: 04/11/2017 00:52:40 »
Quote from: Jerry
I believe that if we figure out that answer we can then figure out how to reach that speed and beyond.

Of course, you could be right; then you would join the ranks of those who have triumphed against established wisdom.  However, I suspect the infinities involved in accelerating a massive object to c be a difficult hurdle to clear. 
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Offline jeffreyH

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Re: What determines the speed of light?
« Reply #4 on: 04/11/2017 08:41:52 »
Quote from: Bill S on 04/11/2017 00:52:40
Quote from: Jerry
I believe that if we figure out that answer we can then figure out how to reach that speed and beyond.

Of course, you could be right; then you would join the ranks of those who have triumphed against established wisdom.  However, I suspect the infinities involved in accelerating a massive object to c be a difficult hurdle to clear. 

If the permittivity and permeability are that limiting for a massless particle then imagine how limiting they are for particles WITH mass. At very low velocities this would not be apparent. At relativistic  velocities it may well be the cause of time dilation. Since to move any percentage faster than an already relativistic speed has to act against the increasing effect of the two limiting factors.
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Offline jeffreyH

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Re: What determines the speed of light?
« Reply #5 on: 04/11/2017 10:26:29 »
One more point. Any inertial velocity can be thought of in the same way as the speed of light. It will be constant in the absence of external influences. Where a medium affects the speed of light this effect is caused by forces for massive particles. So the relationships between forces and media are of interest for study.
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Offline geordief

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Re: What determines the speed of light?
« Reply #6 on: 04/11/2017 11:14:25 »
Quote from: evan_au on 03/11/2017 21:27:30
- ε0 is the permeability of a vacuum (effectively its capacitance, if you put it near two wires)
- μ0 is the permittivity of a vacuum (effectively its inductance, if you put it near a coil of wire)
Are these figures  entirely and simply  as found by repeated observation? They are not the result of any theory ;they are just "what is" and  we have to live with them ?

In a sense are these two figures/numbers /properties  completely fundamental to any theory that might be constructed?

Do they have any relationship to the Planke constant ?(I am ignorant about that ,as I am also really about these permeability and permittivity  constants)
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Offline jeffreyH

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Re: What determines the speed of light?
« Reply #7 on: 04/11/2017 11:24:47 »
The Planck constant was introduced by him to explain black body radiation. He considered it a fudge factor himself. Heisenberg found the same when examining a simple oscillator. He found that while position and momentum were continuous the energy came in discrete amounts. Both he and Born developed matrix mechanics based on Heisenberg's original work on the oscillator problem.
 
Planck's constant is used in many fundamental equations. So it can't be just a fudge factor.
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Offline puppypower

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Re: What determines the speed of light?
« Reply #8 on: 04/11/2017 11:50:50 »
Quote from: katieHaylor on 03/11/2017 12:25:07
Jerry asks:

Why does light travel at  186000 miles per second? I can see after reading comments no one knows 100 per cent for sure. I believe that if we figure out that answer we can then figure out how to reach that speed and beyond.

What do you think?

In our current universe, there is a net conversion of matter into energy, instead of energy into matter. This occurs through the forces of nature; mass burn in stars. What this means, is  energy is a lower potential product in this spontaneous forward process. 

This can also be inferred by results seen in the lab. We can convert energy into matter and antimatter pairs but only at the uppers limits of energy. Matter is at higher potential than energy.

In terms of reference, matter to energy means inertia reference; higher potential matter, is partially converting to the speed of light reference; lower potential energy. The net affect is the speed of light is the ground state of the universe because it is the state of lowest potential. The speed of light is the same in all references, because it is the same ground state used by all inertial references; inertial to speed of light is the same direction for all.

Matter cannot travel at the speed of light, no matter how much energy we use, The main reason is by adding energy to rocket to achieve C, you are moving the potential away from the ground state. Energy needs to be released, to approach the speed of light, via the product side of the reaction.

The question is why is the speed of light the value it is. This question can be rephrased as why is the potential between matter and the ground state the potential it is?  If C was larger, than it currently was, the potential of matter with the ground state would go up, meaning conversions of matter to energy would be too vigorous to allow chemical reality.

If the speed of light was slower, the potential with the ground state would be less, causing a sluggish  movement of matter to energy, which would slow the progress of the universe. The speed of light, as we know it, is like in the fable of Goldie Locks, C is just right for our universe and allows life to appear.

The basis for life is the moderately strong chemical bond called the hydrogen bond. Hydrogen bonding holds the DNA double helix and proteins together, as well as provides the unique properties of water. Even a slight change in the strength of this hydrogen bonding, due to changing the  C ground state, will totally change the properties of the materials need for life. For example, a 10% change in hydrogen bonding, would switch the roles of sodium and potassium ions at cell membranes. This alone would mess-up life as we know it. The universe has life in mind with C the sweet spot.
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Offline jeffreyH

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Re: What determines the speed of light?
« Reply #9 on: 04/11/2017 12:12:56 »
Quote from: puppypower on 04/11/2017 11:50:50
Quote from: katieHaylor on 03/11/2017 12:25:07
Jerry asks:

Why does light travel at  186000 miles per second? I can see after reading comments no one knows 100 per cent for sure. I believe that if we figure out that answer we can then figure out how to reach that speed and beyond.

What do you think?

In our current universe, there is a net conversion of matter into energy, instead of energy into matter. This occurs through the forces of nature; mass burn in stars. What this means, is  energy is a lower potential product in this spontaneous forward process. 

I just have to ask what on earth do you mean? What is a spontaneously forward process?
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Offline jeffreyH

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Re: What determines the speed of light?
« Reply #10 on: 04/11/2017 12:23:29 »
Ok I got the reference.
https://en.m.wikipedia.org/wiki/Spontaneous_process
But converting mass to energy? There is an equivalence yes but conversion?
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Offline yor_on

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Re: What determines the speed of light?
« Reply #11 on: 04/11/2017 14:10:57 »
Sure, there is an idea of 'free falling' thermodynamically. That's what we observe. Does that mean that the 'magnitude' of 'energy' diminish, no, not as I know?

But shouldn't it, in some mean?

It's a very weird universe.
==

You see. What differs that magnitude is not a 'amount', it's just whether it's 'useful', or not. That's the 'heatdeath' of the universe.
« Last Edit: 04/11/2017 14:15:18 by yor_on »
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Offline yor_on

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Re: What determines the speed of light?
« Reply #12 on: 04/11/2017 14:17:51 »
Now please define what  'useful energy' consist of?

Expressed otherwise: Shouldn't there be a quality, property, 'quantity' missing in 'energy' that's no longer useful? Either that or I think you need to introduce some absolute frame from where you measure it.

'The universe'?
And you know what that is?
=

Although 'the speed of light' is not really a 'speed'. It's a property.
« Last Edit: 04/11/2017 14:28:14 by yor_on »
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Offline Petrochemicals

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Re: What determines the speed of light?
« Reply #13 on: 04/11/2017 23:10:59 »
I believe its similar to the space ship analogy about inter stellar travel. The further you go the bigger your space ship, and the more propulsion you need.

 As light is radiation, it will not loose energy through radiation.

As it is massless its only use of energy is for velocity, and it has no inherant drag.

Esentially like a space ship that has no drag and no energy loss. It does not need  to account for its apperatus, or fuel load, essentially energy incarnate the moet energy anything can posess.

 To attempt to go faster than 5he speed of light with outside propulsion destroys the subject as is found in nuclear reactions, energy plus particle at the speed of light.

Unlike bullets or ships, its speed is constant and independant from source of emmision.
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