A Question on One-Way Speed of Light

I still do not know what you believe. Sorry, but you seem to like to hear yourself talk. No attack intended. It’s just that if we do not know clearly what you are trying to communicate, an appropriate response is futile. Either try again, or all I can do is wish you good luck.

I have been told in the thread above by people in a position to know, contrary to my expectations, Lisle apparently has a plausible solution for the distant starlight problem. I do not weigh evidence based on whether I like it. If you cannot in any way measure or infer the one way speed of light, then a massive barrier, one that I thought to be the most persuasive, to the YEC model is removed. What I am trying to communicate is that the instantaneous propagation of light is a stunningly huge concession to the YEC worldview.

That there may be flaws in ASC as a whole will not impede its widespread adoption among Christians. You can be sure the average church goer will take the convention and assume it validates the entire package. I am taken back. This to me is a pretty big deal and I did not see it coming.

Can you please provide a link to this “thread” that says Lisle’s proposal is “plausible”?

I guess you meant this link


Right? Ok, so you said “these people are in a position to know”. Can I ask you why these people’s view of Lisle’s ASC convention must be correct? What if Lisle does not know what he is looking at? Are you open to the idea of questioning his conclusions?

It is not that Lisle’s ASC must be correct, only that the instantaneous propagation of light be permissible. I’m not defending ASC.

Not Lisle, PdotdQ above clarifies that that the one way speed of light cannot be measured because it presumes the convention.

In consideration of the universe, it is permissible with consequences. [The biggest consequence is that Lisle’s universe turns out to be 14 billion years old.]

You stated that you believe the starlight problem barrier may have been removed for YECs.

I have not heard of this removal yet. Can you explain what you mean by this statement?

(Edit is above in brackets)

@RonSewell, while using other synchronicity conventions, such as the ASC is scientifically valid (note, this technique is invented by physicists, not creationists), the other consequences of Lisle’s model is completely untenable. @r_speir did a lot of research on this, you can ask him for more details.

Further, and perhaps more importantly, this ability to pick arbitrary conventions for the one-way speed of light is only true in special relativity. Our Universe does not follow special relativity, but general relativity, where the ability to pick conventional one-way speed of light is generally lost.

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Yes, but the hypothesis is that light speed is infinite in 1 direction and 1/2 in the other. So if you checked .5 seconds after firing the pulse, you could determine if it was faster than light speed, which is a little more than a second to the moon. Send up a bunch of these detectors and test them at different times during the Moon’s orbit of earth and Bob’s your uncle!

It does not matter if you observe the particle(s) on earth first, or the moon first. All you see is a given state and you can be sure the other particle is the compliment. The wave function collapses when you look at either, not when the laser hits. You cannot see a change of state with entanglement.

But if s device measures the entangled particle on the moon, wouldn’t that collapse the wave function?

Yes, but then you cannot be watching its twin on earth, so how would that help?

I’m just going to second this.

Ok. This is what confuses me: Physicists Just Smashed a Record to Achieve Quantum Entanglement in Space

(Edited after rereading article) I took this to mean that the photons were entangled at the satellite and sent to two different ground stations. At the stations the states were measured and compared to verify they had been entangled until the moment of being measured, and did not collapse on the way to the stations.

From Lisle’s article linked in my prior post:
I will show that the one-way speed of light is conventional. It is something that is stipulated by us, and is not an independent measurable property of the universe.

Is this legitimate? It is one thing to claim that the one way speed of light cannot be experimentally determined and it is allowable that light speed be infinite to an observer. The assertion that the speed of light is not a property of the universe but just a convention, however, requires some unpacking for me. In what sense is the speed of light then something “real” at all? Time is experienced as a ratio of things, number of ticks of a grandfather’s clock from sunrise to sunrise, number of rotations of the earth to signals back from voyager satellites, and so forth. Are there no such things as real ratios? Correct me if I’m wrong, but spacetime, along with time dilation and other effects, is still something very definite under special relativity. It sounds like Lisle is saying you can switch between ASC and ESC at your convenience (see the rest of his article). In other words, the space time geometry of the universe is not a property of the universe. What is going on here?

Just because many transforms may be mathematically legal does not necessitate they represent realities from which we get to choose at our leisure, any more there being many string theories which appear consistent does not make them all real, unless you want to make reality itself a subjective morass.

That actually seems right to me.

The word “geometry” comes from the idea of measuring the world. And all measurement depends on measuring conventions.

No, they don’t represent realities. They represent abstractions. And while we may choose at our leisure, the choices are not all equal. Some work far better than others. So we aren’t discussing truths about realities; we are discussing pragmatics about abstractions.

Is that the whole story? Physics references dimensionless quantities. As well, I can choose between Celsius and Fahrenheit, but it is not legitimate to speak of one million degrees below zero in either scale.

More generally, all measuring conventions may be regarded as ratios, which I think is a more suggestive approach.

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In special relativity:

The first statement is correct, you can switch between ASC and ESC at your convenience.

The second statement is wrong. Being able to choose ASC/ESC/or the literally infinite other conventions on the synchronicity has nothing to do with the space time geometry of the universe.

Further, as I said before,

OK. I did read your prior reply previously, and found the reference to GR interesting. I thought we could use special relativity for at least for an idealized flat non inertial frame. Is there anywhere I can find a discussion or paper specific to GR and Lisle’s proposal?

Why would the two way speed of light, which is not disputed by Lisle, be a property of the universe, but the one way speed of light not be a property of the universe? In ESC, the ratio of the two way speed to the one way speed is assumed to be 1:1. Is consideration of the ratio of light speed in respect to direction nonsense, or is there a convention adopted by nature such as GR? Is it even proper to speak of GR as a convention?

Correct. This means that SR is only valid in a small patch of spacetime close to an observer, so one cannot talk about cosmology or the age of the Universe using SR. If it is anything, the Universe is large.

Not specific to Lisle’s proposal. Lisle is not a member of the physics community and does not publish his results in mainstream physics journal, so no physicists write discussions about his proposal. The vast majority of secular physicists don’t even know of Lisle’s proposal.

If you are interested in the synchronicity convention in general, including its fate in GR, you can read: Significance -- Conventionality of Simultaneity

The author of that article is John Norton, a well respected philosopher of physics. You can find the answer to all the questions (except the last one) in your second paragraph there.


Of course that is legitimate. It just doesn’t happen to fit anything. Concern about what fits is pragmatics at work.

Conventions are social agreements. Perhaps you didn’t express your point well.

You are investigating Lisle’s ASC and time conventions in general. In the end, here is all you need to know as far as how all of it it impacts our Universe:

You will not be able to “beat” Lisle in his claim of an infinite one-way speed of light, though you should try. You will learn a lot in the process. [However] In the end, you will say with certainty, “He definitely got it wrong regarding the age the Universe. He never should have tried to impose his idea on a young Universe model.” But in all your reading, don’t miss the discussion here