Speed of light what if question.

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The discussion revolves around a hypothetical scenario involving a massive, indestructible disc spinning in space, with clocks placed at intervals from the center to the edge. As the disc spins, clocks further from the center would experience different rates of time due to relativistic effects, leading to significant time dilation. Specifically, while a control clock remains stationary, the clock at the outer edge could be nearly 100 years younger than the one at the center after 100 years of spinning. Participants debate the feasibility of the disc's rotation speed and the implications of infinite mass and force, concluding that while the outer clocks age slower, they do not exist in the past. The conversation highlights the complexities of relativity and the nature of time as it relates to speed and gravity.
  • #31
AWolf I know what bothered me:

When using Lorentz Contraction the velocity of the observer has to be a fraction of the speed of light it cannot be the speed of light so you could not have v squared / c squared = 1 so you can never end up with 0.

While the square root of zero is zero you can not use it to get a real solution from the equation or any equation.
 
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  • #32
Alex Massi said:
AWolf I know what bothered me:

When using Lorentz Contraction the velocity of the observer has to be a fraction of the speed of light it cannot be the speed of light so you could not have v squared / c squared = 1 so you can never end up with 0.

While the square root of zero is zero you can not use it to get a real solution from the equation or any equation.
Granted, you cannot have a velocity of C, but even with a velocity just less than C, the contraction will result in the outer edge curving back in towards the centre.
 
  • #33
I had never heard of the Lorentz Contraction. I checked a site about it. Isn't it more of an observed contraction, than an object actually contracting? The site mentioned a spaceship flying past an observation post at near C. From the ship the observation post would look contracted. From the observation post the ship would look contracted. It didnt say that the ship or observation post would actually be contracted. It also said that the Lorentz Contraction only happens in the same direction as travel. The observation post would look thinner but still the same height.

Even if the Lorentz Contraction does physically contract an object, it doesn't really matter for this. It doesn't matter how fast the disc spins. Even if it is spinning slow enough for the contraction to be minuet. The outer clock will still be moving faster and still show less time than a clock at the center. So the clock would still be wrong when it came to the RPMs and the number of rotations that happened. It would be off by less than if it were spinning near C but still off and would still show the same conclusion.
 
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  • #34
The theory was used by Loentz to explain the contraction of a object in relation to its motion. Einstein used the basics of the equation for some of his mathematics. Einstein proved that the contraction was not the object changing but a change in space and time.

Tell me how exactly are you going to get to the second clock to see the time and if you go to it will the two clocks be the same time?
 
  • #35
Awolf you are correct the theory works if the speed is 1 mile an hour. Very hard to measure the contraction but it changes. The change would be about the thickness of an atom - my random guess.
 
  • #36
Tell me how exactly are you going to get to the second clock to see the time and if you go to it will the two clocks be the same time?

After 100 yrs on the center or a separate clock. Also after the disc has turned 1,524,240,000 rotations at 29 RPMs that would take 100 yrs. Just stop the disc. Walk out to the clock and check it. This is a what if question. I don't see how something like how would I check the clock matter. No the outer clock will show less time has passed. It has been moving faster. Maybe go back and read the other post. That is what I have said the whole time.

The disc always turned 29 RPMs and made 1,524,240,000 rotations, 100 years worth of rotations at that speed. The outer clock will say only 5 mins has passed. Even though it still made 1,524,240,000 rotations at 29 RPMs. It can't do that in 5 mins. So that means the clock is wrong.

It doesn't matter how fast the disc spins. Even if it is spinning slow enough for the contraction to be minuet. The outer clock will still be moving faster and still show less time than a clock at the center. So the clock would still be wrong when it came to the RPMs and the number of rotations that happened. It would be off by less than if it were spinning near C but still off and would still show the same conclusion

Think of 2 runners on a track. One is on the inside lane the other is on the outside line. The start at a the same starting line and stay in their lanes. Both of the runners run around the track and come to the finish line at the exact same time. Even though they finished at the same time. The runner on the out side track had to run faster. He because he is on the outside lane has to cover more distance in the same time. That is why they have staggered starts for races that go around the track and the runners have to stay in their lanes.

Now imagine a similar situation where the track is moving and the runners stand still on the track. The track is moving at say 30 RPMs for 20 mins(set with a completely stationary clock). That means it will make 600 rotations. The runner on the outside lane will still be moving faster than the runner on the inside lane. If each runner had a clock. Although it would be a very small amount the outside lane runners clock would show less time has passed, cause he is moving faster. At the end of the 600 rotations (which takes 20 mins at 30 RPMs )the outside runners clock may say only 19.999999999999999999999 mins (or something just under 20 mins) had passed. So the outside runners clock is wrong. Why? Because by it moving time passed by it slower. It didnt experience the passage of time at its full rate. Time did not slow down (the track did still rotate 600 times at 30 RPMs which takes 20 mins). The outside runner and his clock didnt feel, age or experience the full 20 mins. That doesn't mean though that 20 mins didnt pass. It did the track rotated 600 times at 30 RPMS, that takes 20 mins.

So what I am thinking is the case is. Time is constant, but when an object moves time passes by that object slower. Also that a completely 100% stationary object would experience the full flow and affects of true constant time. Any moving object would just be off from that time. Or in another words time doesn't pass at its full rate passed a moving object. If the stationary object was a clock. It would show the true passage of time. If an object, created after the stationary clock. Were given a clock then that object moved around the universe. Then after a period of time, the 2 clocks were checked. Even though the clock on the moving object would show less time, and the object would have aged and felt the experience of less time. The stationary clock would show the objects true age. How long the moving object has been in existence.
 
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  • #37
First it was not a statement but a question. Why there was a "?" at the end of the sentence.

In regard to your post you state "go back and read the other post" as if the post contained 100% fact that can be used to prove further theories. The post is interesting but at the same time breaks a dozen proven laws. Actually more like entire segments of the Laws of the Universe. If the math equates to five minutes of time passage of the clock than your comment "so that means the clock is wrong" means you are saying Einstein's math equations are wrong? Something is wrong but I am going to back Einstein on this one.

Your comments about the disc contraction brings up another batch of "what ifs" that are now being used as a foundation of pure fact to prove further "what ifs." Did the contraction post forget to mention that the equation applies to an observer moving in the exact opposite direction of the objects motion. Not an observer moving across the disc 90 degrees from the directional motion.

Has anyone given a thought about the disc post as it would apply to the space/time continuum laws? Has anyone explored the resultant light wave frequency shift from the center to the edge of the disc and the resultant implications? As I recall the Disc Post was presented as a what if to be discussed. It was not intended to be taken as pure fact by the author. Somehow both posts are now excepted as proven science not to be questioned. The Disc post states in the opening remarks that it is a thought to be discussed.

I can say with a fair amount of certainty that the laws that govern space, time, and matter in the Universe cannot be reduced to two runners on a track. Keep in mind this, you cannot know a little bit about this branch of Physics and mix it with what you know about the way things work on Earth because your conclusions would be 100% wrong 100% of the time. If your proof is runners on a track than you would be using that to discuss Sir Isaac Newton's work. If your proof centers around the curvature of space/time caused by a Supernova you would be using Albert Einstein's work.

We return back to my question - Tell me exactly how you are going to get to the second clock to see the time and will the two clocks be the same time? Note you carry the first clock with you and compare the two side by side. Actually prove your answer using the applicable laws of physics that govern the Universe.
 
  • #38
Alex Massi said:
Awolf you are correct the theory works if the speed is 1 mile an hour. Very hard to measure the contraction but it changes. The change would be about the thickness of an atom - my random guess.
The theory works from 1 mile per hour up to 1 mile per hour less than the speed of light, at which velocity the contracted circumference would be approximately 0.3% of the original.

If the Universe is a spinning disc, with the outer edges rotating at a velocity close to the speed of light, then the answer to what is beyond the Universe is perhaps the centre of the Universe. The whole disc contracting back on itself like a big doughnut.
 
  • #39
We return back to my question - Tell me exactly how you are going to get to the second clock to see the time and will the two clocks be the same time? Note you carry the first clock with you and compare the two side by side. Actually prove your answer using the applicable laws of physics that govern the Universe.

I thought I answered it here.
After 100 yrs on the center or a separate clock. Also after the disc has turned 1,524,240,000 rotations at 29 RPMs, that would take 100 yrs. Just stop the disc. Walk out to the clock and check it.
No the outer clock will show less time has passed. It has been moving faster.

If the math equates to five minutes of time passage of the clock than your comment "so that means the clock is wrong"

I didnt do the math on it. I used 5 mins as an example. The point is that no matter how fast the disc spins. A clock on the outer edge of the disc will show less time than a stationary unattached clock. It would also show less time than any other clock on the disc that was closer to the center.

I will make some points then you tell me the ones you agree with and the ones you disagree with. Then we can see where our ideas differ, cause actually from your last post I am confused as to what you think I am saying. Also I am not saying that I am right for sure that "time is constant and it is just the way objects experience it that is relative." So far though nothing has shown me otherwise.

1) The faster something moves the slower it experiences time.

2) This was tested by using 2 atomic clocks. One on Earth the other in a
plane. The clocks were set to the exact same time. The plane flew at like 600 mph for a period of time. When they stopped the plane and compared the 2 clocks the clock on the plane showed slightly less time than the one on the Earth.

3) If you have a disc spinning at a constant RPM. A point or clock on the outer edge of the disc will be moving faster than a point or clock that is closer to the center. This is because the outer point or clock travels a greater distance than the inner point or clock with each rotation.

4) So because the outer point or clock is moving faster it will experience less time than the inner point or clock. As in statement 1.

5) A stationary point or clock that is not attached to the disc will not experience the time delay at all.

6) The disc being turned by a motor set at a constant 30 RPMs. Will make 30 rotations per minute. To make 600 rotations would take 20 mins. Using a stationary unattached clock. Or by just by dividing the 600 rotations by the RPMs.

7) When the disc is stopped after the 600 rotations The outer point or clock would have made 600 rotations at 30 RPMs.

8) The outer point or clock will say less than 20 minutes has passed, because it is moving and thus experiencing the time delay.

9) No matter what the outer clock says. The disc did make 600 rotations at 30 RPMs.

10) 600 rotations at 30 RPMs cannot be done in less than 20 mins.

11) The outer edge clock says less than 20 mins has passed. So it is therefore wrong.
 
  • #40
Try to stir big mass of water in the pool by a mixer. You will see a real picture of your experiment.

Michael.
 
  • #41
I stumbled onto this site by accident. Thought I would post a few times and help out. I can see my help was not needed or wanted. You seem to be highly knowledgeable and even though the forum was set up to help those that wanted academic guidance you have learned all that is known. At least you think you have.

I being a Nuclear Physicist that designs nuclear reactors bows to your superior intellect and will be on my way.

UglyEd read Albert Einstein's book and than answer my question; later in life you will be glad you did.
 
  • #42
As for your post UglyEd all are incorrct but 3, 6, and 7 are true on Earth.
 
  • #43
A (belated) welcome to Physics Forums Alex Massi!

You will have noticed that this thread is in a section of PF called "Theory Development"; what you may not have yet appreciated is the history and current status of this section - please take a look here to get a quick appreciation.
 
  • #44
You seem to be highly knowledgeable and even though the forum was set up to help those that wanted academic guidance you have learned all that is known. At least you think you have.

Alexi I don't think anything like that at all. I really do want to know what the truth is. I also really appreciate your input on this. I feel bad and am sorry if I have upset you. If I am wrong I can except it. I just want to know where I am going wrong. You said that I was wrong on all of my points except 3,6,and 7 are true on Earth.

Here is proof though that my 1st point is correct.

1) The faster something moves the slower it experiences time.

This is a quote from Albert Eisteins book Relativity: The Special and General Theory.

" As judged from K, the clock is moving with the velocity v; as judged from this reference-body, the time which elapses between two strokes of the clock is not one second, but (There is an equation here that shows the seconds, but I wasn't able to paste it.)

seconds, i.e. a somewhat larger time. As a consequence of its motion the clock goes more slowly than when at rest. Here also the velocity c plays the part of an unattainable limiting velocity. "

Here is a quote from another site about time dilation.

"Einstein laid the basis for most
modern theory on time travel in
1905 when he developed his special
theory of relativity. This theory
predicts that time passes slower
for moving objects than for
stationary ones, a phenomenon
termed time dilation. This was a
significant discovery because it meant
that space and time are not absolute
as previously thought.
A clock traveling at the speed of light ticks
slower to a stationary observer than
a clock at rest would."


"This was a
significant discovery because it meant
that space and time are not absolute
as previously thought "

This is the part that I don't see as 100% true. Maybe time is constant it is just that objects experience it at different rates. A completely stationary object would experience time at its full rate. Time slows down for a moving object because it doesn't experience the flow of time at its full rate.

Or like in this quote from a site on space/time.

" But if a traveler were to travel into space and back to Earth a distance of 1000 light years, traveling at 99.995% the speed of light, they would have aged only 10 years while 1000 years had elapsed on earth."

I see that as all true, but from looking at the disc thought experiment. Could you also add to the above statement. That although the traveler has only aged 10 years. The traveler is still 1000 years older. Or in other words the traveler has still been in existence for 1000 years. That constant time has always moved at the same rate. Just only 10 yrs of it passed by the traveler.

Or could you also say that time passes objects at different rates depending on how fast the object is moving? That a completely stationary object would feel the full passage of time? If that stationary object were a clock it would keep track of constant time?


I know my 1st statement
1) The faster something moves the slower it experiences time.
is right. The 2nd statement I made is from a show I saw about space-time and how the above was proven. To me it seems that if the 1st statement is true then everything else should also be true. I just want to know if I am wrong at what point do I go wrong at.
 
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  • #45
Nereid for you to even go there with the link to the crackpot post is not cool. I listed a chain of statements and thoughts as to how I saw them. I just want to know if I am wrong at what point to I go wrong at. Alexi said my 1st statement.

1) The faster something moves the slower it experiences time.

Was incorrect as I showed in the previous post the statement I made is not incorrect. Alexi was incorrect in saying I was.
 
  • #46
See I knew you were smart UglyEd you posted I was incorrect knowing I would respond.

Ok let us review the proof you used. Obviously, Einstein's quote is correct but the second quote explained what Einstein said and usually it is dangerous to use others interpretation of Einstein's work. In this case the second quote is also correct.

Time is used extensively in Einstein's papers. He uses the word time after he explains what Time is in the beginning of his work. The word time has been used here, as literally meaning "my watch slowed down" and that is not Time.
Time is the speed of light. Time does not speed up or slow down. The frequency of light speeds up and slows down. Light is a constant exact speed. The wave frequency can change but the speed is always the same. I repeat the SPEED OF LIGHT NEVER CHANGES.

There is no reason that a mechanical wristwatch with machined gears and a set tension coil is going to modify its mechanical characteristics regardless of your speed. Gravity can effect mechanical motion but that is not a constant. Moving at the speeds we are discussing it would be a variable. These theories are a constant.

Please do not post things like "but a atomic clock shows a difference" because they do but they are effected in the same or similar way as light.

For now please do not use the word time unless it is followed by what the frequency of light is doing. Time is the frequency of light relative to you. If the wave frequency of light relative to you is slower than the frequency of light relative to an observer than your Time is slower.

The speed of light relative to you is Time.

The frequency of light that is our perceived Time is neutral in color. If that frequency is slowed light shifts into the red spectrum (if you do not know what the Red Doppler effect is search the net now). The Earth Time or frequency of light on Earth is your relative time. If I left Earth and went twice the speed of light, Earth’s speed of light, for 100 minutes and stopped than looked at Earth I could see what was happening on Earth 50 minutes before I left. Have I gone back in time? No you have not you have gone twice as fast as Earth’s frequency of light “Time” for 100 minutes. You spent 100 minutes getting there and will take 100 minutes to get back. When you get back you will have been gone 200 minutes. Your relative point has now been returned to Earth so your time is now relative to the frequency of light on Earth. As you left Earth your light frequency was twice as fast as Earth’s Time and when you came back it was half as fast. The point being you cannot go back in time.

The frequency of light on Earth is Time.
 
  • #47
There is a slight error in the last sentence "The point being you cannot go back in time" should have said. You cannot go back in time using this method but it is theoretically possible to go back in time.
 
  • #48
I just did a 20 minute search fact find on the net. Things are worse that I thought Einstein's Theories have been mangled. The sites I looked at vary from the sort of on target to just nuts in there explanations.

As you argue with my post here are the rules. Only one single proof that I am wrong may be posted/discussed and proven true are false than another can be posted. Also 20% of the sites claim that the speed of light is not constant and changes but just by a little not enough to matter. The speed of light is either a constant are it is not a constant it cannot change a little just as a person is either dead or alive. You can not be a little dead.

The speed of light is constant. If the proof you find on the internet first explains why the speed of light changes just a little than do not bother to post it please.
 
  • #49
As you argue with my post here are the rules. Only one single proof that I am wrong may be posted/discussed and proven true are false than another can be posted.

Ok sounds good. One more thing we have to keep this friendly. Like I have said this is how I understand Time to be. I could be wrong but just haven't seen that I am yet. My theory is. Time is constant, objects just experience times passage at different rates.

The speed of light is constant.

This is true and false. It is true in that light always leaves an object at the same speed no matter how fast the object it moving. As in you can't add the objects speed to C to get the speed that light is moving from the object. Also that C doesn't change in a vacuum.

It is false in that light does travel at different speeds through different materials. Light travels fastest through a vacuum.

Here is a quote from a site.

the Theory of Relativity tells us that light always travels at the same speed relative to some observer, no matter what the relative motion of the observer. Thus, light emitted from a moving airplane does not travel with the speed of light plus the speed of the airplane, it travels with the "speed of light", no matter what the speed of the airplane! In a vacuum, light always travels at a speed of 299,792,458 meters per second, no matter how its speed is measured... To be precise, what we usually call the "speed of light" is really the speed of light in a vacuum (the absence of matter). In reality, the speed of light depends on the material that light moves through. Thus, for example, light moves slower in glass than in air, and in both cases the speed is less than in a vacuum. However, the density of matter between the stars is sufficiently low that the actual speed of light through most of interstellar space is essentially the speed it would have through a vacuum, so we don't make much error by ignoring the difference

I can't find the site that showed the experiment that proved that light moved slower through different materials, but from all the sites I looked at. This is understood to be true. Plus you probably just saying C is constant in a vacuum. So yes in a vacuum the speed of light is constant.


Here is my question. If you have 2 clocks set to the same time. One clock remains stationary. Then you fly one around the Earth a at say .5 C. (but any speed will work). After a period of time you compare the times on the 2 clocks. Will the clock that flew show less time has passed than the stationary clock?
 
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  • #50
UglyEd those are valid points worthy of a discussion. This will be our starting validation post. When his post points are analyzed and the validity of his arguments has been decided than we move on. As in my post still stands as is and all understand why – Than next batter up.

I could think of no other way to present this material. 98% of the Internet sites are wrong. Easily proven to be wrong. I have some design work to complete than I will post a reply later tonight.
 
  • #51
cant find the site that showed the experiment that proved that light moved slower through different materials, but from all the sites I looked at. This is understood to be true. Plus you probably just saying C is constant in a vacuum. So yes in a vacuum the speed of light is constant.

This is a frequent topic. Hopefully it will make into our slowly forming FAQ thread.

light ALWAYS propagates at c. In a medium it is periodically adsorbed by the atomic structure. This creates a delay, kind of like driving down a street will lots of stop signs. While you drive at say 25mph, your average speed will be much lower, over several blocks.
 
  • #52
This topic is difficult enough to comprehend, It becomes even more so if the thread thought process is broken. Why I posted that only one opposing view at a time can be presented than I reply than it can be discussed by all.

Integral I am fully aware you are a forum moderator but I am also requesting that you please also follow my requested procedure. On my part I will post a reply in less than 16 hours.

Integral thank you in advance for your consideration and understanding.
 
  • #53
To make this more understandable a few shortcuts will be used.

My post above made the statement that Time is the frequency of light relative to where you were. This is really the first point of understanding needed to go forward into Einstein’s Theories. UglyEd has suggested a view that he believes argues against my statement. I use frequency in my real life work but the more generally accepted word used is wavelength. So we are now discussing the validity of the statement:

Time is the wavelength of light relative to you.

The c will be given a value of 1 to 100
100 = the c in a vacuum

Wavelength will be given a value of 1 to 100
50 = the wavelength of light in a vacuum


There are 4 flashlights all lined up exactly above each other all moving in precise unison of 100 MPH due North.

1. A flashlight in a vacuum = vacuum flashlight
2. A flashlight on the nose of the Space Shuttle in space above Earth but not far enough to be in a vacuum = shuttle flashlight
3. A flashlight on the nose of a jet at an altitude of 25,000 feet above sea level = jet flashlight
4. A flashlight on the hood of a car driving on a road at sea level = car flashlight




UglyEd’s Statements from his post.

A. Time is constant, objects just experience times passage at different rates.
B. Light does travel at different speeds through different materials. Light travels fastest through a vacuum.
C. The speed of light is constant is true and false.


Let us first review the results of B using our 4 flashlights. As the light travels through different densities of
Air UglyEd states that the light speed changes. Therefore we have:

Vacuum flashlight c = 100
Shuttle flashlight c = 98
Jet flashlight c = 96
Car flashlight c = 94

Statement C says it is true and false. The above goes over the false so we will look at the results if it were true. That and Einstein said it was true.

Vacuum flashlight c = 100
Shuttle flashlight c = 100
Jet flashlight c = 100
Car flashlight c = 100

Which one is true well I think B and C are both true. I will go further and state UglyEd thinks they are true, I think they are true, and Albert Einstein knew they where true.

For both to be true than these conflicting statements are missing a variable that is not mentioned, not understood mostly, by the posts on the net and in books.

Time is the wavelength of light relative to you.

As you know velocity = distance divided by time

Velocity or c is fixed – distance is fixed they are moving together at the same 100 MPH – that would leave time

My post above explained to you that the concept of time is already set in our minds from our view of using it. The movie starts in ten minutes, I have to be at the meeting in 1 hour, and thousands of others. That should be considered as time not Time.

TIME IS THE WAVELENGTH OF LIGHT RELATIVE TO YOU

For c to remain constant while passing through the air than c which does not change has a wavelength that does

Lets look at the flashlights once again. While knowing that the wavelength of c in a vacuum is 50. To maintain a constant c as the light passes through the air than the wavelength must increase. The c stays the same but the wavelength does not.

Vacuum flashlight c = 100 and wavelength equals 50
Shuttle flashlight c = 100 and wavelength equals 51
Jet flashlight c = 100 and wavelength equals 52
Car flashlight c = 100 and wavelength equals 53

As the wavelength increases so does Time
As the wavelength decreases so does Time

As we discuss this leave clocks, wrist watches, egg timers, and any other such devices out of your post. That is the time till the movie starts. We are discussing what the wavelength of light is doing and that is Time.



As for your question UglyEd:

“Here is my question. If you have 2 clocks set to the same time. One clock remains stationary. Then you fly one around the Earth a at say .5 C. (but any speed will work). After a period of time you compare the times on the 2 clocks. Will the clock that flew show less time has passed than the stationary clock?”

After removing the devices that signal the start of a movie I am assuming your question is dealing with Time. If person A is on Earth and his Time has a wavelength of 53 and person B traveling at .5 c has a Time wavelength of 25 than:

This is not exact my calculator is not close by, Person B has a Time of one half of Person A. So if a year passes for Person A and Person B uses the same calendar than his would indicate the passage of half a year. Year, month, day, hour, and the rest are fine to use. No more talk of clocks or time please.
 
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  • #54
Alex, you are saying that Light is Time? I don't fully understand how that is. Is this your theory? Or is this something that has been proven, if it is could you point me to a site I could read more about it? Does that mean there is no Time in complete darkness?

As far as my answer to the speed of light is constant.
This is true and false. It is true in that light always leaves an object at the same speed no matter how fast the object it moving. As in you can't add the objects speed to C to get the speed that light is moving from the object. Also that C doesn't change in a vacuum.Light travels fastest through a vacuum. It is false in that. The speed of light can be slower through different mediums
After reading an article (that I have part of lower on this post) I will have to say this part of my answer is wrong.
Light travels fastest through a vacuum.
Light can travel faster than in a vacuum and has been done.

I would like to also point out that Einstein said specifically that a clock will tick seconds by slower when the clock is in motion.
This is a quote from Albert Eisteins book Relativity: The Special and General Theory.

" As judged from K, the clock is moving with the velocity v; as judged from this reference-body, the time which elapses between two strokes of the clock is not one second, but (I attached the equation, it is at the bottom of this post.)


seconds, i.e. a somewhat larger time. As a consequence of its motion the clock goes more slowly than when at rest. Here also the velocity c plays the part of an unattainable limiting velocity.

I don't see where Light is involved here.

Here is a part of an article about light that I found. That discusses the changing speed of light.

"It’s well known that light can travel slower than 186,000 miles a second, depending on the medium it’s passing through. That medium can be as common as air, water or glass. Or it can be more exotic. For example, researchers at the Rowland Institute for Science and Harvard University say they’ve been able to slow light down to 1 mph, by passing it through a chamber containing supercooled atoms.

SPEEDING UP A LIGHT WAVE
Lijun Wang, Alexander Kuzmich and Arthur Dogariu used a different kind of exotic medium in their experiment: The researchers used lasers to “pump” cesium atoms, contained in a 6-centimeter (2.4-inch) chamber, to an excited state that doesn’t occur naturally.
Then they passed a smooth light pulse, lasting about three-millionths of a second, through the chamber. The atoms in the cesium gas were in just the right state to shift the pattern of peaks and troughs in the many wavelengths that made up the light pulse."popped up on the other side of the chamber far sooner than it should have, based on the speed of light in a vacuum. In fact, the time difference — 62-billionths of a second — meant that the peak of the pulse appeared on the far side of the chamber before it entered the near side of the chamber. That’s an instance of what’s known as “negative delay” or “negative velocity,” a phenomenon that seems paradoxical. It was almost as if the light wave could figure out, on the basis of the very beginning of the pulse, how to reconstruct the full peak on the other side."

Here is a link to the site if you want to check it out more.

Link

About your answer to my question. You didnt exactly say true or false, but I take it that you say yes the clock would show less time. Right?
 

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  • #55
First none of this is my theory. If it were my thoughts than I would start each post clearly stating so. Everything I have written is merely what Albert Einstein wrote. Your question "Does that mean there is no Time in complete darkness" is very astute. I myself have wondered the same. The only instance I KNOW OF where there is complete darkness is the area near a Black Hole where gravity is strong enough to capture light. I have my opinions on the material I have studied but I have zero proof they are valid. So you read the materials and form your own opinion, yours may be right as mine may be wrong.

"As judged from K, the clock is moving with the velocity v; as judged from this reference-body, the time which elapses between two strokes of the clock is not one second, but (I attached the equation, it is at the bottom of this post.)" you base this quote to prove I am wrong. Let me explain something to you. Einstein wrote his theories in the early 20th century. His reference to a clock ticking off two strokes was not meant to be taken literally, it was just his way of conveying his thoughts. Just as I used the flashlight as an example. You do not really think they taped a flashlight to the nose of the Space Shuttle do you. He uses time as I use Time. He uses time because he had already proven mathematically what time when he wrote this. What he had already proven is Time is the wavelength of light relative to you. I in no way claimed I wrote the Theory of Relativity I stated in an earlier post I had studied HIS work and would discuss HIS work.

You do not understand that the test "Speeding Up a Light Wave" PROVES my last post, which in its entirety was based on the works of Albert Einstein. The light wave starts to immediately shorten its wave length to reach the maximum possible speed allowed in our universe that of course is c.

I want to state very clearly that all of the posts I have made on this forum is based solely on the writings of Albert Einstein. I have just read every post I made in the forum and I fail to find any reference to my claiming any statement as my own. For the record I in no way lay claim to any fact on this forum posted by Alex Massi.

UglyEd do not say things like that please. In my 30 years of work I have never plagiarized anyone's efforts.
 
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