- Thank you received: 0
Constancy of Speed of Light
- tvanflandern
- Topic Author
- Offline
- Platinum Member
Less
More
18 years 11 months ago #16915
by tvanflandern
Reply from Tom Van Flandern was created by tvanflandern
<blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by Thomas</i>
<br />Is anybody aware of experiments which confirm the invariance of the speed of light in case source and observer are moving relatively to each other rather than moving together relative to some hypothetical 'ether'?<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">In special relativity, the speed of light is constant by postulate, not by measurement. The clocks used to measure the speed must be synchronized in such a way that the speed of light is automatically constant.
When special relativity's postulate is ignored, as in the GPS system, the speed of light is not a constant relative a moving receivers. -|Tom|-
<br />Is anybody aware of experiments which confirm the invariance of the speed of light in case source and observer are moving relatively to each other rather than moving together relative to some hypothetical 'ether'?<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">In special relativity, the speed of light is constant by postulate, not by measurement. The clocks used to measure the speed must be synchronized in such a way that the speed of light is automatically constant.
When special relativity's postulate is ignored, as in the GPS system, the speed of light is not a constant relative a moving receivers. -|Tom|-
Please Log in or Create an account to join the conversation.
18 years 11 months ago #14485
by Thomas
Replied by Thomas on topic Reply from Thomas Smid
<blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by tvanflandern</i>
In special relativity, the speed of light is constant by postulate, not by measurement. The clocks used to measure the speed must be synchronized in such a way that the speed of light is automatically constant.<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">
But the postulate is based on experimental evidence. Wouldn't it have been for the null-result of the Michelson-Morley experiment, it would have never been formulated. The point is however that with M-M experiment the velocity is actually not physically defined as all parts of the experiment are fixed relatively to each other, and the assumption of the earth's velocity being in any way relevant is a purely metaphysical one. That's why I am looking for experiments that have been done with the light source and detector actually moving relatively to each other.
<blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by tvanflandern</i>
When special relativity's postulate is ignored, as in the GPS system, the speed of light is not a constant relative a moving receivers.
<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">
I have read actually contradictory statements regards whether relativity has been taken into account for the GPS system or not. In any case, I feel that because GPS is essentially a military project, one should (for obvious reasons) not necessarily trust all the information that has been released in this respect. I would therefore rather prefer the results of a dedicated civil experiment where one can assume that all the information is being laid open.
www.physicsmyths.org.uk
www.plasmaphysics.org.uk
In special relativity, the speed of light is constant by postulate, not by measurement. The clocks used to measure the speed must be synchronized in such a way that the speed of light is automatically constant.<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">
But the postulate is based on experimental evidence. Wouldn't it have been for the null-result of the Michelson-Morley experiment, it would have never been formulated. The point is however that with M-M experiment the velocity is actually not physically defined as all parts of the experiment are fixed relatively to each other, and the assumption of the earth's velocity being in any way relevant is a purely metaphysical one. That's why I am looking for experiments that have been done with the light source and detector actually moving relatively to each other.
<blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by tvanflandern</i>
When special relativity's postulate is ignored, as in the GPS system, the speed of light is not a constant relative a moving receivers.
<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">
I have read actually contradictory statements regards whether relativity has been taken into account for the GPS system or not. In any case, I feel that because GPS is essentially a military project, one should (for obvious reasons) not necessarily trust all the information that has been released in this respect. I would therefore rather prefer the results of a dedicated civil experiment where one can assume that all the information is being laid open.
www.physicsmyths.org.uk
www.plasmaphysics.org.uk
Please Log in or Create an account to join the conversation.
18 years 10 months ago #17054
by pancurium
Replied by pancurium on topic Reply from Jay Hansen
<blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by tvanflandern</i>
<br /><blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by Thomas</i>
<br />Is anybody aware of experiments which confirm the invariance of the speed of light in case source and observer are moving relatively to each other rather than moving together relative to some hypothetical 'ether'?<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">In special relativity, the speed of light is constant by postulate, not by measurement. The clocks used to measure the speed must be synchronized in such a way that the speed of light is automatically constant.
When special relativity's postulate is ignored, as in the GPS system, the speed of light is not a constant relative a moving receivers. -|Tom|-
<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">
There is evidence that the speed of light is not constant.
Harbinger of Thought
<br /><blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by Thomas</i>
<br />Is anybody aware of experiments which confirm the invariance of the speed of light in case source and observer are moving relatively to each other rather than moving together relative to some hypothetical 'ether'?<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">In special relativity, the speed of light is constant by postulate, not by measurement. The clocks used to measure the speed must be synchronized in such a way that the speed of light is automatically constant.
When special relativity's postulate is ignored, as in the GPS system, the speed of light is not a constant relative a moving receivers. -|Tom|-
<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">
There is evidence that the speed of light is not constant.
Harbinger of Thought
Please Log in or Create an account to join the conversation.
- tvanflandern
- Topic Author
- Offline
- Platinum Member
Less
More
- Thank you received: 0
18 years 10 months ago #17172
by tvanflandern
Replied by tvanflandern on topic Reply from Tom Van Flandern
<blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by pancurium</i>
<br />There is evidence that the speed of light is not constant.<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">We were speaking of the speed of light in a vacuum. Everyone knows that light slows in air, glass, water, etc.
The constancy of the speed of light in a vacuum, or the lack thereof, is a theory-dependent matter. If you accept that SR has been falsified in favor of LR, then the speed of light in vacuum is indeed subject to variation. OTOH, if you interpret reality using SR, then the speed of light in vacuum is a constant by postulate, and no experiment can show otherwise. That is because light signals are used to set the clocks used to measure its speed. -|Tom|-
<br />There is evidence that the speed of light is not constant.<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">We were speaking of the speed of light in a vacuum. Everyone knows that light slows in air, glass, water, etc.
The constancy of the speed of light in a vacuum, or the lack thereof, is a theory-dependent matter. If you accept that SR has been falsified in favor of LR, then the speed of light in vacuum is indeed subject to variation. OTOH, if you interpret reality using SR, then the speed of light in vacuum is a constant by postulate, and no experiment can show otherwise. That is because light signals are used to set the clocks used to measure its speed. -|Tom|-
Please Log in or Create an account to join the conversation.
18 years 10 months ago #14739
by Dangus
Replied by Dangus on topic Reply from
Isn't that sort of akin to measuring how fast the grains of an hourglass fall through to the bottom part by using the hourglass itself to time itself?
"Regret can only change the future" -Me
"Every judgment teeters on the brink of error. To claim absolute knowledge is to become monstrous. Knowledge is an unending adventure at the edge of uncertainty." Frank Herbert, Dune 1965
"Regret can only change the future" -Me
"Every judgment teeters on the brink of error. To claim absolute knowledge is to become monstrous. Knowledge is an unending adventure at the edge of uncertainty." Frank Herbert, Dune 1965
Please Log in or Create an account to join the conversation.
Time to create page: 0.221 seconds