Speed of Dark ???

[GregG]

Hello,
This may seem strange but i just started reading a book that was written by an autistic person and the title is The Speed Of Dark-it was discussed briefly in the first paragraph and explained that there is no such thing as the speed of dark and that dark can only be described as a place where there is no light,being an optician i am of course intriuged by this revelation as we all know what the speed of light is, but is there a speed of dark? and how exactly can darlness be explained? like i said this may seem odd but i thought-(in my own sick little optical way)- that this might make an interesting thread as it will probally drive most of us nuts trying to figgure it out.
Greg G

We do not attach ourselvs lastingly to anything that has not cost us care, labor or longing.

[Texas Ranger]

"dark can only be described as a place where there is no light"..I think you said it all...now, if the color "white" is a combination of all colors, what is the color black?

[Chris Ryser]

Texas Ranger said:
"dark can only be described as a place where there is no light"..I think you said it all...now, if the color "white" is a combination of all colors, what is the color black?

It is the absence of reflected light.

[optigoddess]

A man just walked into our shop yesterday wearing a t-shirt with this phrase....now, think I know what it refers to!

[Pete Hanlin]

If you are intrigued by such scientific notions, may I recommend an entertaining little book I went through during my last trip?

Five Equations that Changed the World is an interesting look at the works of Newton, Farraday, Einstein, Bernouli, etc. Each of the five articles represents an equation (for example, Einstein's Special Relativity). There's a short and entertaining biography of the scientist, an account of how he came to the solution of his particular problem, and then an illustration of how the world was changed.

Its very light reading and will increase your trivial knowledge if nothing else (e.g., Galileo died the same year Newton was born- 1642)...

Anyway, I found it to be interesting. A few paragraphs in the Newton chapter relate how Newton discovered that white light is a combination of all colors (a discovery, btw, that was scoffed by the Royal Institute of Scientists at the time).

Regarding light, one of the things that baffled scientists until Einstein's time was the medium that light traveled through in space (for centuries, scientists believed in a "fifth" element called "ether"... turns out light can travel in a vacuum).

[edKENdance]

Sounds like a Steven Wright bit

[paw]

Darkness is the absence of light the same way cold is the absence of heat.

[Darryl Meister]

Darkness is the absence of light the same way cold is the absence of heat.

Exactly. You can't "remove" darkness or freezing temperatures... You can only add sources of light or heat.

Regarding light, one of the things that baffled scientists until Einstein's time was the medium that light traveled through in space (for centuries, scientists believed in a "fifth" element called "ether"...

It's amazing how we humans make things up to fill in the "blanks" when we don't fully understand something. ;)

Best regards,
Darryl

[edKENdance]

Darryl, just as our brains fill in the gaps to help us along with our perception non? Does the body rule the mind or does the mind rule the body? I don't know.

[Darryl Meister]

just as our brains fill in the gaps to help us along with our perception non?

Well, I guess you could draw an analogy between the two, though they are two very different thought processes.

Our brains "fill in the gaps" and achieve other wonders of visual perception through complex interactions between regions of neurons in our retinas and various parts of the brain and optic tract. Most of this is completely automatic, and you never even think about it. Most of the work is done before we even have a chance to think about it.

On the other hand, "filling in the gaps" in a cognitive sense relies more on decision making. When "primitive man" couldn't understand why it rained sometimes and not others, or why the big warm ball of fire in the sky came and went, much deliberation went on. Eventually, in the absence of any better ideas, they often ascribed it to "magical" forces or perhaps "deified" it and made it into a rain god or a sun god whom they could worship.

This has more to do with basic human nature than anything. We just don't like the unknown. We don't like blank spaces where there should be answers in terms we can comprehend. As time went on, we gave up on the idea of magic, per se, but we still invented our own notions to fill in those blanks, which were often just as mystical, though we gave them more scientific-sounding names to feel better about it. The "ether/aether" used by the likes of Newton may have been called "magic air" a couple of centuries earlier.

Just imagine how many of the facts that we take for granted today were misunderstood, or even considered heresy, a century or two ago.

Best regards,
Darryl

[harry a saake]

Darryl, can you say that under most situations, there is no such thing as total darkness, much the same principle night vision goggles and related items work under. It would seem to have true total darkness, the related area would have to be a vacumm, perfectly sealed.

[edKENdance]

Does anyone know the IOR of our eyelids?

[paw]

"It would seem to have true total darkness, the related area would have to be a vacumm, perfectly sealed."

But Harry, Pete said earlier that light can travel in a vacuum.

Total darkness could only happen in a black hole, where gravity is so strong not even light can escape.

[Cowboy]

Philosophers of our time unite!

If there is a speed of light and traveling so, you actually advance time, could it not be true that, if you travel in darkness, understanding that there has to be an equal opposite (action/reaction theory) that you would reverse time?

Point to ponder.

:cheers:

Cowboy

[Darryl Meister]

It would seem to have true total darkness, the related area would have to be a vacumm, perfectly sealed.

Total darkness could only happen in a black hole, where gravity is so strong not even light can escape.

In general, you're not likely to find "total darkness" outdoors. The problem with space is that most of it is not very dark. You have an unfathomable number of stars out there emitting light. Night vision goggles, for instance, rely on ambient starlight and moonlight, which is simply amplified by the device.

Nevertheless, you can fairly easily create "pitch black" by just blocking out any ambient light. A room with no windows and a well-sealed door would work just fine. Though a black hole would certainly create a dark spot; theoretically, at least.

if you travel in darkness, understanding that there has to be an equal opposite (action/reaction theory) that you would reverse time?

Unfortunately, No. ;)

Best regards,
Darryl

[Cowboy]

"unfortunately, no!"

Daryl, can you prove it?

[BobV]

Folks,

take a tour of some caves here in Missouri...when the tour guide shuts the lights off when you are about a half mile in...tell me that ain't total darkness.

Bob V.

[paw]

Point taken! Apparently light can't travel through rock! Hence, the "blind cave fish."

[Darryl Meister]

Daryl, can you prove it?

Sure. But the easiest way would probably be just to ask BobV if he came out of that dark cave in Missouri before he actually entered it... ;)

I think you are referring to Einstein's special theory of relativity with this line of reasoning. According to the special theory of relativity, time is "dilated" for someone moving near the speed of light. However, this person doesn't really go back in time or into the future, and it doesn't matter whether the person is traveling in light or in darkness -- it just matters how fast the person is going.

Best regards,
Darryl

[BobV]

Darryl,

that's a whole nuther subject, kind of like which came first...the stalagmite or stalactite. of course the answer would be neither...the cave came first so they could both form.

To answer your question, I went into the cave from a lit area (outside), the cave was lit (artificially), so when the artificial lights were turned off, all that was left was a natural black.

Then we went back out into the natural light and it was good. (Is this sounding biblical?)

I better stop now.

Bob V.

[Darryl Meister]

Sorry for the confusion, Bob. I was just using your cave adventure to demonstrate that traveling through darkness won't send you back in time, which Cowboy had asked about earlier... ;)

Best regards,
Darryl

[Cowboy]

Assuming that one person leaves earth and travels one light year, when he returns, it will have been 50 years past on earth, yet the man has only aged one year. Therefore, travel at light speed does in fact advance time, theoretically. So, taken that Light is the opposite of Dark, then would not regression be the opposite of advancement? Hence my origonal theory based on Sir Issac Newton; For every action there is an equal and opposite reaction.
Now I realize that this far fetched, however, has anyone tried to prove it different. All Theories are based on light travel, not dark travel, if in fact there is a speed of darkness. The use of BobV in the cave is invaled as he did not travel the speed of dark.

:cheers:

Cowboy

[edKENdance]

Does anyone have reccomendations for specific lens types or certain coatings for travelling at light speed?

[Cowboy]

This also brings another question that someone once asked me, "Can there be absolute nothing?" My answer is no. Even in a vacuum, there is pressure, a black hole contains gravity, and much of the like. So, I maintain my answer, but does anyone have any thoughts on this subject?

[edKENdance]

Absolute Nothing





It's in the space between the ears.