Science a GoGo's Home Page Forums General Discussion General Science Discussion Forum light speed

quick question to all you smart science people out there. if a vessel was traveling at the speed of light exactly, and had "head lights" on. Would you be able to see the light in front of you??

A vessel cannot travel with the speed of light relative to another reference frame; however, it can travel at a very high speed that approaches the speed of light relative to your reference frame. Within the reference frame of the vessel the speed of light will still be c, so that the light from its headlights will still move away with light speed and will thus still be observed as usual for light within any reference frame. The speed of light does not depend on the speed of the light source; i.e. you cannot catch up with light ever. It does not matter how fast you move relative to another reference frame, the speed of light you observe will alwyas be c relative to the reference frame moving along with you.

Lightspeed is identical for all inertial observers. It is a mathematically unavoidable consequence of Lorentz Invariance. Massed particles cannot travel at lightspeed. The point of view of a photon is not an inertial frame of reference.

what has mass got to do with light?

even if a flashlight is traveling at 1 mph or slower , its light if pointed in the direction of travel would be faster than the speed of light.

mass can be illuminated by a light source but that is about it.

and just because the web site has the word science in it does not mean that these
people are smart?

some of the stupidest people I've ever talked to
held phds.

you determine smart not them and not the piece of paper they have.

ponder this:

the flashlight is already traveling very close to the speed of light.

if the light were switched on would the beam only be a inch or two long?

and would the beam travel any distance should the
flashlight be traveling at the speed of light?
if of course it were possible.

reminds me of a physics instructor that once told me that water would not flow through a pipe of given lenght , I asked him if I crawled inside the pipe if there would be a wall of water that I could stick my finger into.

this made him upset because all of his math told him differently.

always try to use common sence.

Mass has a lot to do with light. Mass is inertia. If light had mass it would have been able to be stationary relative to an inertial reference frame. Because it has not got mass it always move with light speed relative to an inertial reference frame. A vehicle (with mass) moving with a speed v is stationary within the inertial reference frame moving with it. For this reason the light from its headlights will still move with the speed of light away from the vehicle. Galileo's statement of relativity, subsequently incorporated into Newton's first law, implies that any body with mass has an inertial reference frame within which it is stationary (i.e. both its position and momentum are known at the same time). Heisenberg did not appreciate this scientific fact and interpreted his uncertainty relationship, involving position and momentum, incorrectly. This has led to the farce called the Copenhagen interpretation of quantum mechanics, and to the quaqmire called quantum field theory.

http://www.mazepath.com/uncleal/analysis.png
http://www.mazepath.com/uncleal/sunshine.png

You've both handily disproven all of physics and all of science with it. What literally hundreds of thousands of physics graduate students have overlooked during the past 70 years you have trivially stumbled upon.

All solid state devices have vanished, GPS quit, and electric power distribution is no more. MRI machines disappeared along with their superconducting magnets. Batavia, IL is exposed as a giant conspiracy of lies. No more double slit diffraction, no more Poisson spots, no more Airy circles. No more Mie scattering as the inverse fourth power of wavelength - no more blue skies.

No more refrigerator magnets.

physics is a tool box not a stop sign or speed limit sign.

I have not disproven physics I think it is a great
collection of tools.

sort of like a large collection of pieces of peoples minds and thoughts and experimental results.

after all people made these tools.

Being in possession of a fully equipped toolbox is no guarantee against DIY disasters.

quick question to all you smart science people out there. if a vessel was traveling at the speed of light exactly, and had "head lights" on. Would you be able to see the light in front of you??
REP: Wonder why such a question can arise if you are told that you can not travel at the speed of light.;-0

I really cannot understand how you come to all these bizarre conclusions. Why must the Heisenberg uncertainty relationship describe an "uncertain particle" to have all these effects manifest? Can you be bit more scientifically rigorous please? Please derive your conclusions from what I supposedly said incorrectly!

Johnny Boy asks:
"Please derive your conclusions from what I supposedly said incorrectly!"

You said: "Mass is inertia"

And your source of this is?

No doubt your answer will be most enlighteng.

What mass implies is that the body will "resist" from being accelerated; i.e. it will resist from being moved from its position of rest (an equilibrium position) within its proper inertial reference frame (i.e. the inertial reference frame moving along with it). In fact this is where the term "inertial reference frame" comes from. I have read this interpretation many times in different handbooks and treatises when I studied classical mechanics.

Now applying this concept in a lateral way; resistance of an entity from being moved from equilibrium implies the presence of a restoring force. Thus modelling the free electron in its proper reference frame as experiencing a restoring force when an attempt is made to move it, gives a time-independent harmonic Gaussian wave whose quantum mechanical energy must correspond to the rest mass of the electron. Where does the restoring force come from? By assuming the manifestation of a virtual positive charge, Coulomb's law can be used to derive an expression that models the electron charge within the field of an equal positive charge situated over a fourth dimension.

This model indicates that matter and anti-matter could be separated over a three-dimensional interface (our three dimensional space). It also shows that an electron could have excited states (muon and tau?). It also gives a solution when applying a magnetic field along a z-axis. Using spherical coordinates it is found that the angle with the z-axis must be either 0 or pi for the electron mass-energy not to incease. This can be interpreted as a re-orientation of the axis along the fourth dimension relative to the three-dimensional space axes. etc. I think that this model opens up so many novel possibilities that it should be objectively analysed by the scientific community.

Read what you wrote:

1. "What mass implies is that"
2. "applying this concept in a lateral way"
3. "This model indicates"

Is this science? Not where I teach.

I am glad you are not my teacher. Go to the texts on classical mechanics (probably not the ones you use when you teach) and find out what mass implies. There is nothing wrong in physics to extrapolate from one concept to another: read the Feynman lectures. There is no fault to extrapolate and to speculate on a new proposed model; as far as I know this is done every day.If new models are not proposed and analysed on a daily basis science will stagnate. Is this the case where you teach? I will not be surprised. I cannot understand your beef!

Johnny Boy wrote:
"There is nothing wrong in physics to extrapolate from one concept to another"

I agree. But you are drawing conclusions from your extrapolations that violate known physics.

Please refer back to what Uncle Al wrote.

What Uncle Al wrote has not been derived by any logical reasoning. In fact I really do not understand how he reached such absurd and bizarre conclusions. What I write does not violate well-proven known physics in any way; only the interpretation of known physics. Please be more specific; what am I violating?

Uncle Al may lead with his attitude ... but he is generally quite good with his facts.

Al ... rather than giving my impression of what you intended to communicate might I ask you to jump in and spell it out? Thanks.

Thank you Einstein and DKV:

If I told you there were 200 tombs in Egypt?s Valley of the Kings you might reasonably ask me how I derived that result. Many things in science have fixed results derived by mathematics, physics or even common sense.

How did we arrive at a speed of light at 186,281 miles a second? What is there about our Sun light that musters out instantaneously at that speed and never changes? What happens to that blast off that inhibits the speed to stay forever the same and why do we think that this scenario is logical?

I think this question is on topic with the posting. Whose going to give us an answer?
jjw

XXXXXXXXXXXXXXXXXXXXX
violate known physics
XXXXXXXXXXXXXXXXXXXXX

laser beam --> container of cessium

known physics violated !!

Paul, could you provide a bit more explanation of this claim? Not all of us are on the same wavelength that you are.

Amaranth, moderator

sure no problem heres a few for starters.

http://archives.cnn.com/2000/TECH/space/07/20/speed.of.light.ap/
http://news.bbc.co.uk/1/hi/sci/tech/841690.stm
http://www.zulenet.com/see/nyt.html
http://physicsweb.org/articles/news/4/7/8
http://www.omniology.com/BrokenSpeedOfLight.html
http://www.thekeyboard.org.uk/Faster%20than%20light%20speed.htm
http://www.timetoeternity.com/time_space_light/speed_of_light.htm
http://www.cbsnews.com/stories/2000/07/19/tech/main216905.shtml

there are probably thousands more
here--->http://www.google.com/search?hl=en&q=the+wang+cesium+light+speed+experiment&spell=1

Hey, thanks for your help. Besides that bit of fighting you guys had, the sights and explanations helped alot.

10000 years from now, if man is still alive, they will look back at our science and compair it to our understanding if the cavemans chants for the sun to return.

10,000 years? Try 100!

na, 100 years they will only compair us to romans or such.

Magnetism is a consequence of the theory of relativity.

Dear Count:

Magnetism came before Einstein.
Magnetism can not be a consequence of a theory.
If Einstein is correct he exposed fundamentals.
jjw

to get back to the original question.

time is relative to the speed. that has been proven. if you were able some how to go as close to the speed of light as it is possible for matter to do, time for you would have slow down so much that the tiny difference in the speed of light would make it appear that the light was still moving away from you as normal.

I posed the question earlier with no takers.

I repeat with an explanation.

We recite that light travels at about 186,281 miles per second because that is what we measure in this solar system. Forget that reference data.

Who and how does science prove that the measured speed is what it should be everywhere? What mathmatics are there to prove our sun produces light at that speed because of some physical factors that are measurable? Does the assumption exist solely on the basis that the speed measured must be the speed every where? No proof required to arrive at reasons for 186,281 miles per second?
jjw

Dehammer,
You posted:

"to get back to the original question.

time is relative to the speed. that has been proven. if you were able some how to go as close to the speed of light as it is possible for matter to do, time for you would have slow down so much that the tiny difference in the speed of light would make it appear that the light was still moving away from you as normal."

Its called 'relativity` because you cannot measure
your velocity except relative to something else.
No matter what your speed, you will perceive the
velocity of light as 'C`.
It is a property of space/time. If you think in
terms of space alone you are led into error.

( google 'Fitzgerald/Lorentz` contraction.)

jjw004,
You posted:
"We recite that light travels at about 186,281 miles per second because that is what we measure in this solar system."

Miles/second is distance/time - a property
of 'space/time` not 'space`. - Same admonition.

Pragmatist

"Some days it's just not worth chewing
through the Restraints."

Pragmatist posted


Its called 'relativity` because you cannot measure
your velocity except relative to something else.
No matter what your speed, you will perceive the
velocity of light as 'C`.
It is a property of space/time. If you think in
terms of space alone you are led into error.



your speed is how fast your going. it is not something that has to be related to something else.

to measure it, you have to use a seperate frame of referance, say the compareatively motionless stars. at that point you have to use time to measure it.

it has been proven that the faster you go, the slower your the time is in your time reference, as compaired to those out side at a standstill.

in this case the reference is to the speed of light.

if you go close to it, time slows down for you in comparison to the the person that it is not moving in relation to light. if he could see you, to him you would appear to be motionless. if you could see him, he would appear to be moving in a blur.

light would move away from you at light speed, but since your at 99.9999 percent of that speed, it hardly gets ahead of you in terms of the outside observer. in your terms it moves ahead at exactly the same speed as it would otherwise, since your time has compressed for you.

to claim that time is the same no matter what flies in the face of experments done by the air force in the early 70's. it also flies in the face of all understanding of the theory of relativity.

in order to measure things like speed and time, you have to have a frame of reference. since the speed of light is a constant, its frequently used. the problem occurs when your trying to compare things that happen at faster speeds, with a reference of zero speed.

our planet is traveling around our sun at something like 66,000 mph.

how fast is our sun traveling through our galaxy?
how fast is our galaxy traveling through our universe?

we may be traveling beyond our conception of the speed of light at this time...

if a calculation were taken then all of these speeds should be included in the calculations and the center of (our) universe should be the begining point used in the calculation.

if and only if our universe is the only universe.

if not then we would need to know how many other universes there are , and where is the center point of all the universes.

so is the current speed of light correct?

I wonder...

to the "DA MORGAN" arguing program loaded on this forum.

I already know you dissagree ok.

so whats the point.

I would argue with you but theres no reason to anymore.

to pragmatist:

You say to jjw
You posted:
"We recite that light travels at about 186,281 miles per second because that is what we measure in this solar system."

You then offer:
"Miles/second is distance/time - a property
of 'space/time` not 'space`. - Same admonition."

Is that supposed to be some mathematical or physics demonstration of WHY light travels at 186,218 Mps. Pleas show the formula that provides that result based on the sun's mechanics or the physical nature of photons that result in that speed. Your " admonition " is misdirected and of no value to me. Thanks anyway.
jjw

186,281 is NOT the speed of light we measure in our solar system. Never has been ... never will be.

The speed of light is different in different media. That is the entire principle by which prisms and refraction work.

The number is nominally the speed of light in the near-vacuum of space. And it is, to the best of our knowledge, the same everywhere in the universe (though I personally have some doubts).

DA you should check your data and not be so anxious to argue from error with people.

Speed of light
?The speed of light in a vacuum is exactly 299,792,458 metres per second (or 1,079,252,848.8 kilometres per hour, which is approximately 186,282.397 miles per second, or 670,616,629.4 miles per hour). This value is denoted by the letter c, reputedly from the Latin celeritas, "speed". Note that this speed is a definition, not a measurement, since the fundamental SI unit of distance, the metre, has been defined since 1983 in terms of the speed of light?one metre is the distance light travels in a vacuum in 1/299,792,458 of a second. The speed of light through a transparent medium (that is, not in vacuum) is less than c; the ratio of c to this speed is called the refractive index of the medium.
Cherenkov effect in a "swimming pool" nuclear reactor. The effect is due to electrons travelling faster than the speed of light in water.?
-----------------------------------------------------------------------------------------------------------

So 299,792,458 meters * .62137 = 186,282 miles per second. This is not the best recitation of the speed. Other more focused sources convert to about 186,281.75 miles per second.
It is really curious that you would jump in on such a basic thing to argue. Like your previous argument that the Sun does not rotate at the equator as I said. Lighten up.
jjw

I've read what I wrote and read what you wrote several times and I can't find what you are objecting to?

The original statement was:
"We recite that light travels at about 186,281 miles per second because that is what we measure in this solar system."

And it is not correct. We measure many different speeds for light in our solar system depending upon the medium in which it is traveling.

Again ... clarification requested.

Da you are nitpicking without reason.

Everbody knows that light speed will vary under circumstances wherein the light passes through some medium or other. I specifically stated that the speed of light in a vacuum was measured at 186,281 miles per second, that is the vacuum of space in the solar system near earth. It has been so measured by NASA ans some smart fellows a long time age.

http://itotd/com/articles/284/

"Meanwhile, Foucault was working on a different but equally clever technique, which he demonstrated the following year. Foucault?s method was to shine a sharply focused beam of light onto a rotating mirror, and from there onto a fixed mirror. Once the light hit the fixed mirror, it bounced back onto the rotating mirror and then back toward the source. But because the mirror was rotating, the angle at which it was positioned had changed slightly by the time the beam made its return trip. Consequently, the reflected beam did not line up precisely with the original. Foucault could easily measure the angle between the original light source and the reflected beam, and along with known constants (the distances between the various surfaces and the speed of the mirror?s rotation), it was a matter of a few straightforward calculations to convert that small angle into a representation of speed. Using this technique, Foucault produced a measurement of 298,000 km/second (185,167 miles/second), which is shockingly close to the modern measurement of 299,792 km/second (186,282 miles/second), keeping in mind that the latter figure applies only in a vacuum; light travels more slowly in air."

I guess you have a measurement of your own creation and that is OK too, keep it secret.
jjw

Paul,
The center of the universe resides in your navel,
or anywhere else you choose.
That is the meaning of relativity.
It is pointless to try to create a 'privileged
obsever`.
The point of the 'Big Bang` model is that
everywhere is the center.

Dehammer,
You state that speed is independent of a frame of
reference and then proceed to create one.

>say the compareatively motionless stars.

>it has been proven that the faster you go, the
>slower your the time is in your time reference, as
>compaired to those out side at a standstill.

Yes -Standstill relative to????

>in this case the reference is to the speed of light.
Relative to what???

>light would move away from you at light speed,
>but since your at 99.9999 percent of that speed,
>it hardly gets ahead of you in terms of the
>outside observer. in your terms it moves ahead at
>exactly the same speed as it would otherwise,
>since your time has compressed for you.

Yes, the observer is important.
The observer would also see you as foreshortened
in the direction of travel which impacts your
measurement of 'C` from your point of abservation.

The point is that 'C` , Distance/Time is a
constant for each observer. You can't separate
the two.
You're trying to mix the observations of different
observers indiscriminantly.
Pick a frame and stick to it, then normalize
the observations from different frames to
your chosen frame.
To understand, you must consider this subject in
terms of space/time.
If you try to think in terms of space or time
alone you're apt to fall into error.

Pragmatist

"Lord, are we worthy of the task that lies before us,....or are we just jerking off?"

jjw004 wrote:
"Everbody knows that light speed will vary under circumstances wherein the light passes through some medium or other."

1. Not everyone knows it.
2. You told me I was incorrect now you tell me being correct is nitpicking.

You can't have it both ways. So what was the point of your first post?

a black hole emits no light, is this because the black holes gravity does not allow light to escape, or is it because the objects inside the black hole travel into the center so fast that the objects and its light is gone ...converted into energy and thats why we cant see it.

we can see the energy as it leaves the hole so
energy can escape.

(--> energy has no mass)

if this is the reason we see no light then the speed of light could not possibly be as most concieve it to be.

no, i was demonstraiting the point. two different observers see the things differently due to the effect the speed has. speed itself is not dependent on the frame of reference,

compaired to speed of light the stars are practically motionless.


the speed of light though a vaccuum is a constant, that makes it something that can be used as a frame of reference anywhere.


they time distance is constant, but your ability to observer it is diminished as time is compressed. on the other hand light moving away from you is not moving away as fast due to the fact that you are almost the same speed.

let me us a different analagy.

two observers see a train pass a crossing. the train blast the whistle as required.

one observer on the ground near the hears the whistle. as the train approaches the sound is higher due to the fact that sound travels though air at a given pressure and tempature at a constant speed. as the train passes the sound pitch drops. niether the pitch that was heard prior to or after the train passes are the same sound that the person in the train hears. if the train stops and whistles, it will make the same sound as the person in the train heard, but not either of the pitch heard by the one on the ground.

the person on a starship traveling just below the speed of light will have his time streached out as he approaches. the light leaving his ship will be moving away at a matter of a few miles per hour difference. (the speed of light will be the same, but the difference between it and the speed of the ship will be small). but since his ability to see the time in reference to the light, has been slowed, it will appear to be the same as normal.

to the outside observer, who is not moving realitive to light, will see the person in the ship compressed and motionless. he will also see that light is still moving the same speed, and will see the ship is just slightly less than light.

actually we see the energy that was almost captured by it, but escaped from just outside the event horizon.

dehammer wrote:
"actually we see the energy that was almost captured by it, but escaped from just outside the event horizon."

If we assume Steven Hawking and quantum mechanics are wrong.

actually that is if they are correct. the energy we see is from the event horizon. as things begin to accelerate and time begins to slow. matter is torn apart. that releases energy. that is what we see. once it gets beyound that point, it does not escape normally, only matter being shot out of the poles are coming from inside. and that is only visible if the pole is pointed at you.

I am sorry but I canot let this sentence from dehammer pass: i.e.

"if you go close to it, time slows down for you in comparison to the the person that it is not moving in relation to light. if he could see you, to him you would appear to be motionless. if you could see him, he would appear to be moving in a blur".

light is moving relative to all persons with a speed c; i.e. all persons are moving "in relation to light" (whatever this means) with a speed c". If a person moves relative to you with a speed approaching light speed, you will (according to his reference frame) move relative to him with a speed near light speed. There is no "blur". According to both observers the time of the other observer seems to be passing more slowly; however, within both frameworks the local time passes at the same rate the so-called proper time rate.

im afraid im having trouble with this.

if two ppl are moving at the same speed in relative to each other, they will see each other moving normal. they will be affect identically. to them, everything will appear to be normal. what will not seem to be moving normal is the things going slower in relation to light. these things will seem to be moving much faster. the slower the other things are moving in relation to light, the faster they will appear to the ppl moving at near light speed. to someone who is not moving in relation to light, will see them hardly moving. that is because time has not dialated for them (if that is the proper term, im not really sure - what else do you call it when time slows for you).

This where you violate the most basic postulate of relativity. To say "someone is not moving in relation to light" is the same as saying that light is stationary relative to this person. According to Einstein's postulates this can never be the case. Light will always move with a speed c relative to any person even when different persons are moving relative to each other they will each still measure a light speed c. This means that time becomes a coordinate which can be transformed from one reference frame to another. So if you transform the proper time within a reference frame moving relative to you into your reference frame, then YOU will experience the time to be slower than it is in the original reference frame from which you have transformed it. The time does not actually slow down in that reference frame. I hope this is of help.

totally wrong. i have no idea where you are coming claiming that if someone is stationary to light, light must be stationary to him.

perhaps you missunderstoon me. light is a constant.that make is something that can be used as a universal reference point. being stationary in relation to light mean that light is moving away from you at precisely light speed. someone at zero light speed is not moving at all.

if you are moving in relation to light then light moving in the same direction as you has slightly less speed in relation ship to you and light moving in the opposite direction is moving at slight faster that light speed in relation to you. this does not mean light is actually moving faster, because it cant. what is changed is its relation to you.

if light moved at relationship to the person, then the person in the ship moving .99 light speed moving at 1 away from him. while the person who was standing still would see it moving at 1.99 light. that does not make since. light moves at a constant. at does not move at a speed in relation to someone. the person in the ship would see it moving away from him at .01 times the speed of light, but due to time dialation (or compression which every the term is) it will seem to move away much faster.

if you slow down in relation to time you have to slow down in relation to everything else.

Oh I suspect JohnnyBoy understood you quite well.

You just wrote:
"perhaps you missunderstoon me. light is a constant.that make is something that can be used as a universal reference point. being stationary in relation to light mean that light is moving away from you at precisely light speed. someone at zero light speed is not moving at all."

Which clearly demonstrates that your score on understanding 20th century physics, well really 100 year old 20th century physics is a resounding zero. You just don't get even the most basic of Einstein's concepts.

It would be absolutely impossible for light to be moving away from you at anything other tan "precisely light speed."

Impossible.
Absolutely.
Totally.
Impossible.
There is no other choice.

Thank you DA.
The other postulate of Einstein that dehammer does not understand is that there is no universal reference point; all inertial reference frames, with whatever speeds they move relative to each other, are equivalent. If you transfer an observer from one to another and he cannot see the reference frame from which he came, he will conclude that he is stationary. If this were not the case, one would not have been able to walk from the back to the front in an aeroplane.

please explain this the person one is not moveing. person two is moving at .99 percent of light. light is moving away from the second person at light speed, so how fast is the SAME light moving away from person two.

light has only one speed. it cant move away from two ppl at two different speeds.

let me do this in another way.

person 1 is standing still. person 2 is moving away in a plane doing .99 mach (the speed of sound). how fast is the sound wave (from the plane traveling away from person 1) traveling in relation ship to person 1)

the answer for those who cant figure out simple physics is simple. sound travels at a given speed at a given air pressure at a given tempature no matter who is measuring it. the person 1 will measure the speed at the speed of sound. the person in the aircraft will measure it at the speed of sound. yet in relation to the jet, the sound wave is only traveling a small amount faster than he is.

the same is true of light. it has a given speed. einstein proved it. test since then have proved it. our understanding of the distance of object in space is based on this. if speed light changes depending on how fast the person or object generating it is moving, all of our understanding of the size of the universe, not to mention the placement of the stars, will have to be completely rewritten.

(note: for the sake of simplisty i use mach as being the exact speed of sound. aircraft mach numbers are actually just a little bit faster due to the fact that an aircraft traveling at precisely mach would soon have a lot of trouble due to the vibrations caused by traveling at that speed. i cant explain it that well, but being a veteran of the usaf, ive learn a few things concerning mach capable a/c)

light moves away at its speed. if your moving at a different speed, the difference in the speed and yours would not be precisely light speed. that has been proven.

have you ever heard of something called redshifting.

its a long time understood principle.

light has frequency. the color you see is a product of the precise frequency or combinations of frequency of the light that reaches your eyes.

when a object is moving towards you, since light cant speed up the wavefronts are compressed, causing the frequency to increase. this increase cause the light to appear to be reder than it would otherwise. simularly object moving away from you have the frequency of their wavefronts spread out causing the light to be blueshifted (appears to be more blue). this allows scientist to determine the approximate speed and direction of stars in relationship to the earth (or more precisely the observer). if light moving from a star that was approaching the earth moved at precisely the speed of light in relationship to the star, it would be moving faster in relationship to the earth and would therefore never redshift.

a simular situation occurs with train whistles. if you stand at a crossroad when the train blows it whistle, it will sound a certain way depending on its speed in relationship to you. if the train is motionless, it will sound the same as it does to the engineer. if the train is moving towards you the sound increases in pitch, sounding higher in scale than it does to the engineer. as the train moves away, the pitch drops, sounding lower than it does to the engineer. in light this is called redshifting and blue shifting. the speed of light in a vaccuum and the speed of sound at given pressure and tempature are both constant.

if your correct, einstein and all the other scientist are wrong. all the star maps nasa has made are wrong. all the understanding of the movements of the planets are wrong.

i am aware that ppl will see what they see no matter what. since you cant change the placement of your center of awareness, (at least most ppl cant) your not going to see anything from any different perspective than that. the car moving 120 miles an hour will be moving towards you weither its moving along the road or is parked and your falling (at least until impact then everything changes).

i am also aware that there is no "universal refernce point". but you can specify something as a reference point and the speed of light is a good one since it has a constant speed. in any converstation there has to be a reference point or there cant be any understanding.

how much understanding would there be if you were talking with a red shoe as a reference point and the next guy was talking about blue fish. a discussiong of apples and oranges would be with a reference point of fruit, not apples or oranges. otherwise there is no understanding.

Yes, that's right. It is the case, however, that if you assume Coulomb's law and special relativity, then you can derive all of the Mawxwell equations. You don't have to postulate a magnetic field, Faraday's laws etc. It can all be derived mathematically.

The speed of light is 1 in natural units. In theoretical physics it is customary not to distinguish between space and time and to use the same units for both. In high school, physics students are often wrongly taught that Length, Time and Mass are incompatible.

dehammer asks:
"please explain this the person one is not moveing. person two is moving at .99 percent of light. light is moving away from the second person at light speed, so how fast is the SAME light moving away from person two."

At light speed.

Both obsevers measuring the speed of light will measure the exact same value.

I believe that we are all arguing at cross purposes here. Dehammer has a point when the firts observer measures light speed and the speed of the second obserrver relative to the inertial reference frame of the first observer. He will then see that the second observer catches up partially with the light moving away from the second observer; i.e. the light moves away at the speed c-v where v is the speed of the second observer. If this were not so there would not have been a Doppler shift for light; however, the second observer will still observe the light moving away from him as moving with a speed c relative to his own reference frame. In special relativity it is of utmost importance to carefully specify the reference frame relative to which an observation is being made. It is for this reason why two observers moving relative to each other can differ on whether two events are simultaneous. If it is simultaeous in one reference frame it is not so in the other.

the speed of light will be measured by both to be the same, but the one that is moving at nearly the same speed will, if he can overcome the time dialation problem, that the light is only a small amount faster than him. if he cant over come it. the fact that he has slowed down so much will make it appear to him to still be moveing the same speed. this is because he will be moving only 1/386000 as fast as the guy that is not moving in relation to light.

JohnnyBoy wrote:
"He will then see that the second observer catches up partially with the light moving away from the second observer;"

dehammer has no point. He doesn't understand elementary school level relativity.

He points out the issue rather clearly, above, when he says "if he can overcome the time dilation problem."

When pigs sprout wings and fly.

Time dilation isn't a problem to overcome ... it is the law.

at our lvl of understanding its does appear to be unavoidable. but then again. it was less than 1.25 centuries ago that "man could not fly" was considered a law too. there might be a way of overcomeing it that we havent the slightest clue about. by the same tolken getting to .99 c is at this time beyound our capacity too. Its a "law" that it would take infinite energy to reach that point. therefore if you total arguement is based on what is the "law", why are you even bothering to post. if time dialation slows your perception to 1/7 that of an outsider, and you are traveling at 6/7 the speed of light, light will seem to be moving at precisely the same speed. but since you will mass 7 times that of what you were originally how would you get to that speed anyway.

we are not discussing things that are possible now.

you do seem to be trying to wrestle me into the reverse of what i was originally saying but im not. if your doing some political game of pushing ppl into the opposite arguement, look else where.

as i have said, light speed is the same no matter what speed you are doing.

time dilation can make the difference between what speed you are going and the speed of light seem to be the same as it would appear to a outsider observer. this is my original point and what im saying all alone.

argue what you want, the speed of light leaving the second person is no faster or slower than the speed of light leaving the person in the ship.

dehammer, maybe you understand what you are saying, but you say it in such a way that it is confusing. Just agree on the following:

1. both observers will measure the same light speed c relative to their reference frames respectively; even though they move relative to each other.

2. Each observer will see a Doppler shift when looking at the other observer and the light moving from that observer, but this does not mean that any of the observers are actually catching up with light within their respective reference frames.

your 1. assumes that in the process of getting to that speed we dont learn to over come time dialation. in my original statement i stated what you are saying. prior to being insulted and told i know less than nothing.

2. i dont know if doppler shift is the proper term. they do see each other being forshorten in the direction of the movement. doppler is more related to frequency.

i am assuming that you are talking about a large differnce in speed, rather that them having a difference of a few feet a minute.

dehammer wrote:
"your 1. assumes that in the process of getting to that speed we dont learn to over come time dialation."


dehammer wrote:
"2. i dont know if doppler shift is the proper term."

It is. And if you don't know that then you have absolutely no business pontificating on the subject. You should be asking people who do understand it to explain it to you.

dehammer wrote:
"i am assuming that you are talking about a large differnce in speed, rather that them having a difference of a few feet a minute."

The amount of the difference in speed is irrelevant.

dehammer should take a look here.

Point 12:

Hi dehammer,

DA Morgan answered you correctly so I will not expand on it.

You must stop thinking that when you observe time dilation it is really happening within the framework moving relative to you. Neither does the increase in mass you see of a body moving relative to you manifest within the framework moving with that body. Similar for length contraction.

This argument is even applicable in Galileo's relativity. The kinetic energy you measure for a body moving relative to you is NOT present within the reference frame moving with that body.

two objects or ppl moving at the same speed and directions in relationship to each other will have the same time dialation effected on themselfs as the other. therefore they will not see a difference. to use da analagy, two ppl moving in an aircraft in the same direction will see the same distance between them at the front of the aircraft as at the back of the aircraft. someone setting in a seat will see them both move, but to the eyes of the ppl moving there is no change bewteen them.

simularly a person that was at a point in space that was stationary to light would see both of the ppl move extreamly slowly. but the two of them would see each other move at normal speed, due to the fact that they were affected the exact same way.

lets me move alittle out of known science for a sec to explain this a little bit.

according to einstein and others its impossible for something in our universe to move faster than light. the corrolary is that if something could excape some how from our universe momentary, it would have the potensial to go beyound light. NOT necissarily the capacity, just the potensial.

for this theory (its not mine by the way, i wish i was this smart) to be understandable you have to keep in mind the punt boat. its a boat that the pusher using a pole to push against the bottom of a river. to a passanger in the boat. the boat itself is motionless, while the water and the shore moves past. to the shover, the punt is moving underneath him, and the river and shore are moving past him. to the person on the shore the punt and the shover are both moving.

as this theory goes if you were to create a field around a ship, that acted as an interferance interface, something that seperated you from the rest of the universe, all the rule of the universe would apply inside the field and outside the field. only at the interface would their be a change and that would be the field would seperate the two from each other. according to this theory the engines would have their own seperate fields that in effect created a tunnel though them. it has been proven that mass can bend light and in this theory its used to turn photons into the engine. at this point a shover of some sort would attempt to accelerate the photo. since it cant change its speed, the ship moves instead. the interface would creat the effect of movement on ice, allowing the field to accelerate beyound light. since its neither energy or mass its not affected by the restriction of objects moveing faster than light. basically it would simply be twising the universe around it. the ppl inside the ship would be motionless in relation to the universe they were in contact with so they would not be vialating the restrictions against moving faster than light. thats the theory at least

now if this ship was moving at the exact speed of light, light moving forward of the field would not be moving at all, in relation ship to them. light moving in the opposite direction would seem to be moving at twice the speed of light since they were moving 1x light and the light would be moving 1x light. they would not be affected by the time dialation due to the fact that in relation to the unverse they were in contact with they were motionless.

now if they were moving at .99 light and were moving next to a ship that was doing the same in the same direction without the field, (according to what i was reading recently on the net) the ppl in the second ship would be 1/7 as deep measureing front to back (accounding to the direction of movement) and would be moving at 1/7 as fast. two ppl in the second ship would see each other moving at 1/7 of normal, but their preception would be slowed to 1/7th so they would see it as normal. to them the ship in the field would be 7 times longer than it should be and the ppl in it would be moving at 7 times normal speed.

its possible that we are saying the same thing in different ways.

dehammer wrote:
"simularly a person that was at a point in space that was stationary to light would see both of the ppl move extreamly slowly. but the two of them would see each other move at normal speed, due to the fact that they were affected the exact same way.

lets me move alittle out of known science for a sec to explain this a little bit."

Why don't you not move outside of known science and try just fixing what you wrote above. Wrong again! Why are you writing this stuff? Where did you get the idea any of it is valid?

where did you get the idea that its not. as i pointed out its theory. i also read the stuff that was on the net about relativity.


think about this. if your correct then if something ever goes near the speed of light, the atoms are not going to be able to funtion together because each will be distanced to the other by the relativity. if im correct the atoms will be able to be the same in relation ship to the near by atoms and the components in relationship to the components of the same atom.

no, everything moving the same has to be affect the exact same, therefore in relation to the things around it moving the exact same speed everthing will be appear to be normal. otherwise, its a mute question becuase nothing will be able to approach even a small portion of light without the atoms tearing each other apart.

Dear dehammer,

Maybe you have your own way of saying things; but I cannot follow you. Either I am stupid, or else as Mark Twain purportedly said: "Today I have met a man who knows more things that are not so than any other man I have met".

dehammer wrote:
"as i pointed out its theory"

No it isn't. Theory does not equate with any wild-eyed concept that can be written down in a sentence using nouns ad verbs.

Learn what a "theory" is.

Johnny Boy ... I think you have as clear an understanding of dehammer as anyone. He can't tell a theory from a fiction. Can't tell the difference between a meteorologist or climatologist and a geologist or botanist. And seemingly is incapable of demonstrating integrity by acknowledging when not just wrong but REALLY wrong.

theory is something that is projected from what is known, has some facts that are pr oven, and some things that are not yet proven. once they are tested, either the theory is discarded, corrected or proven.

leonardo de vinci had a theory of flight. if you look at his diagrams many of them have been proven wrong. does that mean that it was useless. no. it was advanced by other ppl. today as a result we have the capacity to fly to the moon or even other planets. the method of getting to the stars is still theoretical. had you asked many of the ppl of da vinci's time, they would have told you that flight was a "wild-eyed concept that can be written down in a sentence using nouns ad verbs."

relativity is still considered a theory even though there has been some proof, because as extensive as it is, there are still some areas that have not been tested.


really, i am the one that cant tell. i quote a well known source, that tells you that meteorologist are interested in the short term weather conditions, while you maintain that they are the ones that are interested in long term. these are called climatologist, which you don't acknowledge. so far i have not discussed botanist, so how would you know if i knew who they were or not.

before you claim ppl are wrong, why don't you find out the reality of this world.

you cant even quote your own sources right.

Johnny Boy, i understand what I'm trying to say, and logically i cant see how it can be other wise. some of what i understand is also being said to tell me I'm wrong. again if its what I'm saying and your saying, how can i be wrong and you be right. due to what was said here i have been reading up on this, and there is a lot i don't understand and stay away from. perhaps i do understand it and am saying it in a way that confuses everyone. perhaps my image of what I've learned is in err. perhaps what you are saying is comfusing me. i just cant see it happening logically.

either way its obvious that I'm not going to be able to convince you and da is getting to the point that hes not worth discussing. he getting to insulting. since he even argues with dictionary definition and claims that anyone that follows those definitions is wrong, ill not be responding to his insults here anymore.

its been enjoyable discussing this subject with you, Johnny Boy, and with a few others. good day to you.

dehammer wrote:
"theory is something that is projected from what is known, has some facts that are pr oven, and some things that are not yet proven. once they are tested, either the theory is discarded, corrected or proven."

NO! And not just NO but damned NO!

http://en.wikipedia.org/wiki/Theory

Please try educating yourself just once before posting.

Can you guys please stop this idiot slanging? If you have science stuff then post it, otherwise don't.

[attempt to get thread back on topic]

Faster Than Light Effect Baffles Boffins
Physicists are scratching their heads after seeing light travel through a doped optical fiber almost instantaneously. The researchers plan on taking the experiment further and putting one of Einstein's key tenets to the test...

http://www.scienceagogo.com/news/20060411212755data_trunc_sys.shtml

[/attempt to get thread back on topic]

i have.


from http://en.wikipedia.org/wiki/Theory

there are ppl that are working on faster than light theory and this is one of them. in order to prove or disprove whether or not ppl can go faster than light, the must first speculate, then theorise, then look for ways of disproving or proving the theories.

i understand how this works. its been theorized that things can go faster than light if they can seperate themselfs from the things in this universe. its possible that we might never go to .99 light, if we can learn to go around that restriction first. from what ive read the speed of light restriction is only a theory, albet one that has had some test that support it.

i wonder if they could create an energy field that would use what ever it is that cause the second pulse to be created, and project it in front of the ship. then the data from the ship would hit the field long before the ship, creating two copies. then if the second hit the original they would cansil out leaving only the version of the ship created in by the field, which would repeat it causing the ship to effectively skip though space. it would arrive at its destination long before the light from its launch arrived.

Hey this is my first post here and I'm just a sophomore in highschool. I'm obviously very interested in science and I came across this site when I was reading an article about elecrtron entanglement.

Anyway I'm trying to understand more about this topic now. I know light, even from a stationary object, can go faster than the measurment of the speed in a vaccum. "Scientists have seen a pulse of light emerge from a cloud of gas before it even entered."

So if you could explain this example that I am going to put together after reading all posts thus far.

So imagine the experiment to measure the speed of light using one stationary mirror and one rotating. Imagine all of that equipment was on a desk along with observer 1. Observer 2 is stationary.

Now assume the whole desk (and observer 1) is moving 99.99% of the speed of light. I imagine that observer 1 would see the same thing as if the desk were stationary.

Heres my real question. Would observer 2 see the light as moving 1.9999 times the speed of light? From what I've read it seems not, but why?

You are correct to conclude that observer 1 will still see the same result; because observer 1 and the equipment remains stationary relative to each other no matter how fast the desk is moving.
The point you have to realise is that observer 2 will always (also) measure the speed of light as c relative to his/her "stationary" position, no matter how fast the desk moves relative to him/her. According to observer 2, the second mirror will move away from the light reflected from the first mirror. So the light will have to travel a further distance to reach the second mirror. I hope it helps.

welcome. sorry but my understanding of this pheonomon has been question to much for me to give you a good answer.

please do keep the question coming. curiosity has its own rewards.

Thanks for the posts but I still have some questions.

Imagine a spacecraft moving close to the speed of light. Observer 1 is in the spacecraft and observer 2 is outside. I am trying to keep in mind that speed is distance/time and the person is aging slower traveling near the speed of light.

They both are holding a flashlight in the same direction and turn them on exactly when they are next to eachother.

Will observer 1 see the 2nd flashlight moving across space in slow motion? In relation to observer 2's stationary position will the 1st flashlight be moving faster? Will it apear to observer 2 that the 1st flashlight is affected by a dopler effect because the source of the light is moving close the the speed of the light? Thanks in advance.

Both observers see the light moving at c.

Empire,
It's called relativity.
There is no such thing as 'stationary` except as
compared to a selected observer.
There is no absolute frame of reference.
To restate your question: Two observers are
traveling with respect to each-other at a
substantial fraction of C, each emitting light.
What do they observe?
Each will see a blue shift on approach.
Each will see a red shift on departure.
Each will observe time dilation and flattening
in the other.
Each will see the same relative velocity
in the other.
Each will measure C as the same.
Pragmatist

I am sorry I was off-line yesterday. Both observers observe from their respective reference frames within which each one is of the opinion that he is stationary. If both switches on a flashlight along the direction in which they are moving, the trailing observer will not see any light coming from the leading observer. The leading observer will see the light from the trailing observer approaching him with a speed c; however, it will be redshifted (Doppler shift) because the leading observer will see the slower moving trailing observer moving away from the leading observer. If the leading observer points his flashlight backwards towards the trailing observer, then the trailing observer will also see this light travelling towards him with the speed c. It will also be redshifted because the trailing observer will see the leading observer moving away from the trailing observer. I hope this is of help?

Okay I get what you're saying now...BUT who, and how, did someone come to the conclusion that the leading observer would see a redshift as opposed to a light approaching slowly?

that came from an understanding of wave principles.

its the same for train whistles.

if you stand near a train crossing, as the train approaches, the whistle goes higher "redshifting" in to higher frequencies. this is because sound cant change its speed for a given temp and pressure. therefore the waves are closer together, increasing the frequency of the sound. after the train passes, the waves are farther apart causing the sound to drop (the same as blue-shifting for light). doppler radar does the same thing with radar to give a better understanding of clouds.

astronomers have seen that galaxies that are moving away from us have a distinctive redshift and those (few i believe) moving towards us, are blueshifted.

with the observer, the light cant move at any different speed that it does, therefore the light will be redshifted as he moves forward.

Origionally posted by Empire:
"Anyway I'm trying to understand more about this topic now. I know light, even from a stationary object, can go faster than the measurment of the speed in a vaccum. "Scientists have seen a pulse of light emerge from a cloud of gas before it even entered."


You should understand that the effect referred to is
a result of a change of the shape of a pulse of light.
The pulse itself, as a whole, does not violate 'C`.

While something might come of the study of this effect in the future,
right now it is just a curiosity.

It seems that i just cannot get to my computwer in time. this time i fell ill and had to spend two days in hospital. Thank God for antibiotics!

Accordng to the trailing observer (who is under the impression that he is stationary) the leading observer is moving away from him. Vice versa, according to the leading observer (who is under the impression that HE is stationary) the trailing observer is moving away from him in the opposite direction. Both observers measure the SAME light speed and the same speed v with which each is moving away from the other. Therefore both observe a redshift in the light emanating from the other observer.

I am sorry I used the qoute command instead of the edit command. I am still a bit weak from the fever I have had.

ok check this equation out al=006843/,00912<1>=fa,zx-474758809-0909707[08

Hmm, this is a good one. This question appears also in the Cornell U physics class.I will give you the standard, mainstream answer from same webpage.They have a whole bunch of cool problems on that website. Here goes the answer:

If we admitted by ABSURD that the rocket COULD be accelerated to run at .99999c speed (it cannot, no massive particle can run at c) , the light from the headlights would STILL run at c in front of the rocket and wrt the rocket! So, we would see the light cone of the headlights.
I know that you may have received a lot of other answers but this is what SR predics. Unfortunately, we cannot put it to test

Sugeo: Time does not pass for a photon. It would be reasonable to assume that the theoretical rocket traveling at c would similarly not experience time.

I'm not sure your assumption holds.

Though neither does the entire analog as it is, it appears, impossible to test.