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Reversing And Accelerating The Speed Of Light
Space Daily ^
| Jul 25, 2006
| Staff Writers
Posted on 07/25/2006 10:13:18 AM PDT by Ben Mugged
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To: Just another Joe
Yes. The deduced implication, backed up by later posts, was "if nothing practical comes of this in 7 years then it's worthless, so don't bother."
To: Red Badger
Already been posted... tomorrow!
42
posted on
07/25/2006 12:20:21 PM PDT
by
evets
(God bless president George W. Bush!)
To: Ben Mugged
Everybody knows that the Scientist will one day increase the speedlimit on light so that ships can go faster without breaking the law. Saw it on Futurama...so it must be true.
43
posted on
07/25/2006 12:26:31 PM PDT
by
Conan the Librarian
(The Best in Life is to crush my enemies, see them driven before me, and the Dewey Decimal System)
To: ctdonath2
"if nothing practical comes of this in 7 years then it's worthless, so don't bother." And to a lot of people, that is the attitude.
"What has it done for me today?" is the way a lot of people look at it.
They don't see, or don't know, that a lot of things that they use in their everyday life took longer than 7 years to develop.
My original question was to FReepers interested in this type of thing to see if they had any insights into what might be developed out of this in the shorter term.
If it was misconstrued, I apologize.
44
posted on
07/25/2006 12:29:22 PM PDT
by
Just another Joe
(Warning: FReeping can be addictive and helpful to your mental health)
To: FreedomNeocon
The phase velocity of electromagnetic radiation may under certain circumstances exceed the speed of light in a vacuum Does that cause Cherenkov (sp?) radiation or is that only for particles?
45
posted on
07/25/2006 12:32:47 PM PDT
by
techcor
To: FreedomNeocon
I never was totally comfortable with the whole "Light is both a wave and a particle" explanation.Once you understand relativity, it makes perfect sense.
46
posted on
07/25/2006 12:44:18 PM PDT
by
RightWingAtheist
(Creationism is to conservatism what Howard Dean is to liberalism)
To: Ben Mugged
47
posted on
07/25/2006 12:47:05 PM PDT
by
freeangel
( (free speech is only good until someone else doesn't like what you say))
To: techcor
Cerenkov radiation occurs when a particle plows into a substance such as water and momentarily exceeds the speed of light in that medium. That causes the weird blue glow around some nuclear reactors that are water damped.
48
posted on
07/25/2006 12:51:34 PM PDT
by
RightWhale
(Repeal the law of the excluded middle)
To: RightWhale
Cerenkov radiation occurs when a particle plows into a substance such as water and momentarily exceeds the speed of light in that medium Then the excessive energy that has to be disposed of during the velocity change generates radiation? Is this true of all mediums? When light transitions from water to air to space does it accelerate? Where does it get the energy to accelerate? Does it absorb it from the medium it is leaving?
To: PatrickHenry
50
posted on
07/25/2006 1:25:11 PM PDT
by
King Prout
(many complain I am overly literal... this would not be a problem if fewer people were under-precise)
To: Ben Mugged
It is not the light that generates Cerenkov radiation but the particle. The light will be generated while the particle exceeds the speed of light in the medium.
51
posted on
07/25/2006 2:34:59 PM PDT
by
RightWhale
(Repeal the law of the excluded middle)
To: Ben Mugged; RightWhale
Then the excessive energy that has to be disposed of during the velocity change generates radiation? Is this true of all mediums? When light transitions from water to air to space does it accelerate? Where does it get the energy to accelerate? Does it absorb it from the medium it is leaving? IIRC, light doesn't actually "slow down" in a medium like water, it just takes longer to pass through it because it makes multiple short "pit stops" along the way, but still travels at the same constant velocity between stops.
52
posted on
07/25/2006 4:25:29 PM PDT
by
Ichneumon
(Ignorance is curable, but the afflicted has to want to be cured.)
To: sauropod
53
posted on
07/25/2006 4:28:37 PM PDT
by
sauropod
(Giving money and power to government is like giving whiskey and car keys to teenage boys." PJO)
To: Ben Mugged
"When light transitions from water to air to space does it accelerate?"No. The velocity of light in any medium, including the vacuum, is fixed. It is fixed, because of the electromagnetic and spacial properties at those coordinates. The velovity of the electromagnetic energy is given by:
c = 1/sqrt(e * eo * u * uo)
where eo and uo are respectively, the permittivity and permeability of the vacuum. e and u are respectively, the dielectric constant and permeability of the material if present. They represent an interaction strength at each point. That interaction takes time, so energy moving from one point to the next requires a delay, or interaction time at each point. Light emerging from one medium to another doesn't accelerate, it just encounters different interaction times.
54
posted on
07/25/2006 4:31:33 PM PDT
by
spunkets
To: Ichneumon
The speed of light in a medium is related to the refraction it undergoes per Snell's law and the speed is inversely proportional to the index of refraction. It is not internal micro- or pico-reflections but the quality of the medium to sustain the wave characteristics of light that slows light down. The slowing of light to a foot a second in Bose-Einstein concentrate is due to the index of refraction of the medium being very high. The index of refraction of a pure vacuum is 1.0000 . . . by definition. If the index of refraction is negative then the light would go backwards. Of course, what the ultimate reality might be probably can't even be guessed.
55
posted on
07/25/2006 4:36:54 PM PDT
by
RightWhale
(Repeal the law of the excluded middle)
To: RightWhale
I thought the angle of reflection always equaled the angle of incidence. If the refraction index is negative, the angle of reflection would be less than the angle of incidence and if the refraction index is good enough, could actually equal the angle of incidence. In that case, the refractive material would be the perfect reflector and if standing in front of one, you would see yourself regardless of your viewing angle.
To: PatrickHenry
To: Fighting Irish
You just don't know what you are talking about. The fact of the matter is
So there.
To: FreedomNeocon
"Soukoulis and his University of Karlsruhe colleagues have also shown that both the velocity of the individual wavelengths, called phase velocity, and the velocity of the wave packets, called group velocity, are both negative, which Soukoulis said accounts for the ability of negatively refracted light to seemingly defy Einstein's theory of relativity and move backwards faster than the speed of light."
59
posted on
07/25/2006 9:23:02 PM PDT
by
Southack
(Media Bias means that Castro won't be punished for Cuban war crimes against Black Angolans in Africa)
To: Physicist
"Continuing, he explained that the pulse flowing backward also releases a forward pulse out the end of the medium, a situation that causes the pulse entering the front of the material appear to move out the back almost instantly. "In this way, one can argue that that the wave packet travels with velocities much higher than the velocities of light," said Soukoulis."Is he saying that he can transmit wave packets (read: potential data) faster than C for the length of his negatively-refracting medium?
60
posted on
07/25/2006 9:26:21 PM PDT
by
Southack
(Media Bias means that Castro won't be punished for Cuban war crimes against Black Angolans in Africa)
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