The universe appears "old", but it is still less than 10,000 years old

[Optimistic Mysanthrope]

The two-way speed of light is isotropic in ASC - It's only the one-way speed that would be anisotropic. So the one-way speed could be 50 billion times faster than c.

Except that there is no evidence whatsoever that that is the case.

Well, no. That's kinda the point. If there was evidence, it wouldn't be a convention. It's what Lisle's relying on.

Except that one could argue from symmetry and make a perfectly reasonable argument that we would expect the one-way speed of light to be the same or nearly the same to the tiniest fraction of a percent as the two-way speed of light. Why? There is no scientific reason to suppose otherwise, no physical property of light that would support it being other than symmetrical and constant. Once again, we are talking tiny fractions of a difference, and no matter how you count up those differences, you can NEVER get a 10,000 year old universe. Ever. So your claim that it isn't an adequate argument against a 10,000 year old universe just doesn't fly.

I completely agree with you. Unfortunately, the evidence currently doesn't. What we're left with is essentially an argument from incredulity. Unless of course, we find another basis on which we can disprove it. Arguing against ASC using the speed of light simply doesn't cut it.

[Zen Badger]

Even if a one way measurement of the speed of light doesn't give you a precise, to the nanometer measurement.

It doesn't matter, it is sufficient to demonstrate that it isn't infinite.

And that is all you need to debunk Lisles hokum.

[Optimistic Mysanthrope]

Even if a one way measurement of the speed of light doesn't give you a precise, to the nanometer measurement.

It doesn't matter, it is sufficient to demonstrate that it isn't infinite.

And that is all you need to debunk Lisles hokum.

No it isn't sufficient, that's the whole point. It's got nothing to do with the accuracy of measurements, it's about having to assume an isotropic convention in order to measure the one-way speed. If you read up on it, you'll see why it debunks absolutely nothing. In an anisotropic convention, time dilation is caused by a change position, not velocity. So if you synchronise two "clocks", you lose all certainty of them remaining synchronised as soon as you move them.

[orogenicman]

Even if a one way measurement of the speed of light doesn't give you a precise, to the nanometer measurement.

It doesn't matter, it is sufficient to demonstrate that it isn't infinite.

And that is all you need to debunk Lisles hokum.

No it isn't sufficient, that's the whole point. It's got nothing to do with the accuracy of measurements, it's about having to assume an isotropic convention in order to measure the one-way speed. If you read up on it, you'll see why it debunks absolutely nothing. In an anisotropic convention, time dilation is caused by a change position, not velocity. So if you synchronise two "clocks", you lose all certainty of them remaining synchronised as soon as you move them.

It is not unreasonable, given the laws of physics, to assume that the one way speed of light is (within a fraction of a fraction of a unit of measure) equivalent to the two way speed of light. That measuring that one-way speed may be problematic is not evidence in support of a 10,000 year old universe, which is what the warped one is trying to do. If you measure the one-way speed of light between two points that are, say 100 meters apart, the difference between the synchronization of the clocks will be so tiny as to be utterly negligible.

[Optimistic Mysanthrope]

That measuring that one-way speed may be problematic is not evidence in support of a 10,000 year old universe, which is what the warped one is trying to do.

You're right, it can't. But it can't be used as evidence against it either.

If you measure the one-way speed of light between two points that are, say 100 meters apart, the difference between the synchronization of the clocks will be so tiny as to be utterly negligible.

That's true, but the time between emission and detection would still be an exact match to that caused by positional time dilation predicted by an anisotropic convention. Using that kind of experiment, you have to assume the very convention you are trying to prove - the results are meaningless.

I don't agree with ASC any more than you do but after reading up on it, I can see why any attempt to measure the one-way speed of light is futile. I'm grateful to Statler for introducing me to it. Whether we like it or not, isotropic light is not the only game in town - at least for the time being

[orogenicman]

That measuring that one-way speed may be problematic is not evidence in support of a 10,000 year old universe, which is what the warped one is trying to do.

You're right, it can't. But it can't be used as evidence against it either.

Most certainly it can. Any measure of the speed of light, be it one-way, or two-way, that involves a fraction of a fraction of a percent difference in measurement is never going to give you a result that is any closer to a 10,000 year old universe than the currently known standard speed of light in a vacuum. Since the difference will always be a fraction of a fraction of a difference, + or -, you are still going to have a result that approximates 299,792,458 m / s. Given the distance to the most distant object known using current light measurements, you will never get a result that will give you a 10,000 year old universe, no matter how much special pleading you do. why? Because it will never change the standard candle enough to make such a significant difference between what we know it to be, and what the warped one wants it to be.

http://arxiv.org/abs/1212.2259

All experiments attempting to verify the invariance of speed of light directly are based on two-way speed measurement. The challenge in one-way speed measurement, the requirement of spatially separated synchronised clocks, can be possibly circumvented by measuring the speed of light travelling in a closed path. An apparent violation of the invariance principle has been recently reported in the first experiment attempting to measure the one-way speed of light utilising this concept. This experiment is reanalysed here. It is found that the results of the experiment can be explained within the framework of relativity, without requiring any violation of the invariance principle.

http://arxiv.org/pdf/1212.2259v2.pdf

https://medium.com/the-physics-arxiv-blog/fcc5f05c5e44

[Optimistic Mysanthrope]

Most certainly it can. Any measure of the speed of light, be it one-way, or two-way, that involves a fraction of a fraction of a percent difference in measurement is never going to give you a result that is any closer to a 10,000 year old universe than the currently known standard speed of light in a vacuum. Since the difference will always be a fraction of a fraction of a difference, + or -, you are still going to have a result that approximates 299,792,458 m / s. Given the distance to the most distant object known using current light measurements, you will never get a result that will give you a 10,000 year old universe, no matter how much special pleading you do. why? Because it will never change the standard candle enough to make such a significant difference between what we know it to be, and what the warped one wants it to be.

That's true, but the time between emission and detection would still be an exact match to that caused by positional time dilation predicted by an anisotropic convention Using that kind of experiment, you have to assume the very convention you are trying to prove - the results are meaningless.

I'm having to use my phone at the moment, I'll read the articles when I get a chance.

[orogenicman]

Most certainly it can. Any measure of the speed of light, be it one-way, or two-way, that involves a fraction of a fraction of a percent difference in measurement is never going to give you a result that is any closer to a 10,000 year old universe than the currently known standard speed of light in a vacuum. Since the difference will always be a fraction of a fraction of a difference, + or -, you are still going to have a result that approximates 299,792,458 m / s. Given the distance to the most distant object known using current light measurements, you will never get a result that will give you a 10,000 year old universe, no matter how much special pleading you do. why? Because it will never change the standard candle enough to make such a significant difference between what we know it to be, and what the warped one wants it to be.

That's true, but the time between emission and detection would still be an exact match to that caused by positional time dilation predicted by an anisotropic convention Using that kind of experiment, you have to assume the very convention you are trying to prove - the results are meaningless.

I'm having to use my phone at the moment, I'll read the articles when I get a chance.

Please do. Read the articles.

[Optimistic Mysanthrope]

I've just had a quick look. The experiment uses reflectors - it's not measuring the one way speed.

[orogenicman]

I've just had a quick look. The experiment uses reflectors - it's not measuring the one way speed.

Yes it is, because there is only one observer, not two. The experiments for two-way speed of light measures the round trip speed of light between two points, hence the synchronization issue. This experiment eliminates that problem by only using one point of measurement. In other words, the starting and stopping point is at the same location, thus there is no synchronization issue. That they used mirrors to get the light back to the origin is irrelevant to the measurement because light reflecting off of a mirrored surface doesn't change velocity, only vector direction. That the entire apparatus rotates and they get the same results verifies the Michelson-Morley experiment. You should also read the last link.