light propagates at c + v?

DaveC426913 said:
It takes a book. Read up on Einstein's train experiment to see why light rays from moving sources do not drift. It involves time dilation.
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there is no time dilation involved since the source and the detector are moving at the same speed and located in the same gravitational potential.
 
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BdS said:
Thats not what the experiments are showing so far.
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Can you show or reference any experiemnt that shows light to be moving at anything else other than "c'
DaveC426913 said:
False.
You are definitely out of your depth.
You have made a classic error that catches many uninformed people in the 'rocketship turns on its headlights' thought experiment.
Rocket travels at .99c. Turns on its headlights. Does the light beam move at 1.99c? It does not. You have not accounted for time dilation.
You really, really need to read up on this a bit.
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When cranks particularly religiously driven ones, realise how presently accepted science has pushed any need for any deity into near oblivion, it brings forth a fanatical desire and hate of the discipline of science, and like the Sunday preacher bellowing Fire and brimstone, they are forced into defending their deity/religion by offensive, illogical, and pseudoscientific claims re science.
My only "support" for this current illogical rant by this troubled soul, is at least he is in the right section.
 
It is a shame that you refuse learn about reality but that is your choice.
 
BdS said:
Take a mounted laser and shine it against the wall from a distance of 1 metre. Draw a dot on the wall where the laser light is and keep it on for a year. If light travels at only c then we should detect a drift of up to 0.767188mm from the dot we drew on the wall.
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Let's keep trying at this one.

Let's say Alice is doing this experiment in her lab.
She sets it up like you describe and turns it on.
She measures the time it takes the light to travel that 1 metre. What time does she measure?
 
She's going to measure it as having taken 3.3 nanoseconds - the time it takes light to travel one metre.

Agreed so far?
 
Your silence is deafening and his question is just silly because I already showed that in the OP so obviously I agree with it.
 
BdS said:
Your silence is deafening and his question is just silly because I already showed that in the OP so obviously I agree with it.
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What you agree with and what you say is 100% totally irrelevant.
If you believe you have anything invalidating standard accepted science/cosmology, then stop your petty childish trolling, and submit a paper for appropriate peer review from your peers.
It's as simple as that......
 
BdS said:
Your silence is deafening
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It was actually your silence. I posted my question two days ago.

BdS said:
I already showed that in the OP so obviously I agree with it.
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But you're getting lost along the way.


So we agree, Alice measures the speed of light to be exactly c. My question to you is "who exactly, in that setup, measures the velocity of light as being greater than c?"
 
DaveC426913 said:
So we agree, Alice measures the speed of light to be exactly c.
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Yes in her moving frame.
DaveC426913 said:
My question to you is "who exactly, in that setup, measures the velocity of light as being greater than c?"
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The experiment and Alice, because they are moving and they still only detect c. Which means the photons are traveling at c + v with Alice and the experiment and thats why Alice and the experiment only measure c, because its all in realtime motion.. The external observer measures the c + v directly.
DaveC426913 said:
It was actually your silence.
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Sorry about that.
 
BdS said:
The experiment and Alice, because they are moving and they still only detect c. Which means the photons are traveling at c + v with Alice and the experiment and thats why Alice and the experiment only measure c,
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Let's be clear. Alice measures the laser as traveling the appropriate distance in the appropriate time. She measures it as traveling at c.

Oh. Did I forget to mention that Alice has no idea where she is? She woke in a windowless room, after being unconscious for (according to her watch) several days. Long enough to have launched her in a rocket which is now coasting at an unknown speed through space. Or not. She might just as likely still be on Earth.

Her experiments with the laser tell her nothing about where she is or how fast she is moving. No matter what she does, she measures the laser beam moving at c.

BdS said:
The external observer measures the c + v directly.
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And there's the rub. Where is this external observer?
 
DaveC426913 said:
And there's the rub. Where is this external observer?
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The coordinate system im tracking it all on.
DaveC426913 said:
Let's be clear. Alice measures the laser as traveling the appropriate distance in the appropriate time. She measures it as traveling at c.
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Yes but she is moving.
DaveC426913 said:
Oh. Did I forget to mention that Alice has no idea where she is?
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Shes in the coordinate system im plotting, only using the velocities I can prove. And those velocities cant be denied...
DaveC426913 said:
She woke in a windowless room, after being unconscious for (according to her watch) several days. Long enough to have launched her in a rocket which is now coasting at an unknown speed through space. Or not. She might just as likely still be on Earth.
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Unfortunate for her, but I live on earth and have eyes and the earth has a big window to the heavens where I can measure things
DaveC426913 said:
Her experiments with the laser tell her nothing about where she is or how fast she is moving. No matter what she does, she measures the laser beam moving at c.
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Since everything moves, she may not know her speed, but she can rest assured that she is moving.

Sorry I've got a bit of brain drain tonight and its late here, so im hitting the sack. Good night.

.
 
BdS said:
DaveC426913 said:
And there's the rub. Where is this external observer?
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The coordinate system im tracking it all on.
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Are you, the tracker, moving along with Earth? Or is Earth moving with respect to you, while you are "stationary"?

BdS said:
Shes in the coordinate system im plotting, only using the velocities I can prove. And those velocities cant be denied...
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OK, I see where you're getting lost.

Velocities are relative. You can demonstrate that Earth and Sun are moving with respect to each other, but you cannot prove whether one or the other is "stationary". You can demonstrate that the Sun is moving with respect to the galaxy, but you cannot demonstrate that anything is moving in any absolute sense.

One can only measure velocities with respect to other objects, which might themselves be moving.

If you are here on Earth, in the Milky Way, and I am on Thrae in Andromeda, we each see the other as moving wrt us, but which of us gets to claim it is the other one moving?
 
BdS said:
Yes in her moving frame.
The experiment and Alice, because they are moving and they still only detect c. Which means the photons are traveling at c + v with Alice and the experiment and thats why Alice and the experiment only measure c, because its all in realtime motion.. The external observer measures the c + v directly.
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No, an external observer would measure the speed at c. The Andromeda galaxy and milky way galaxy are approaching each other at about 69 miles/sec. The speed of the light from Andromeda as measured on earth is c, NOT c + 69 miles/sec.
 
DaveC426913 said:
OK, I see where you're getting lost.

Velocities are relative. You can demonstrate that Earth and Sun are moving with respect to each other, but you cannot prove whether one or the other is "stationary". You can demonstrate that the Sun is moving with respect to the galaxy, but you cannot demonstrate that anything is moving in any absolute sense.
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Sorry dont agree. I can absolutely prove the earth is moving around the sun and the solar system round the galaxy. Nothing is stationary.
DaveC426913 said:
One can only measure velocities with respect to other objects, which might themselves be moving.
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Yes, but moving none the less. the experiments dont detect that motion drift, so I dont care whats moving relative to what for the experiment. I only care that it is moving.
DaveC426913 said:
If you are here on Earth, in the Milky Way, and I am on Thrae in Andromeda, we each see the other as moving wrt us, but which of us gets to claim it is the other one moving?
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First you measure Andromeda to other points of reference and those points to other points and determine Andromeda motion, then you do the same for the milkyway. And you get your answer.
origin said:
No, an external observer would measure the speed at c.
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Not what the experiments show.
 
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