It is not the problem, but the question.

You are assuming that this will happen: all lights will appear on at once.

The experiment is to prove that this is the case... Or not.

Please respect the thread's topic.

you are full of it, so excuse me if I do not take you seriously. You are unfit to be a moderator, your prejudices are blinding you.

You are a really poor excuse of a moderator and editor. Instead of name calling why don't you try presenting arguments for your convictions? Or is all you can do is hide behind insults and your status?

Then you shouldn't bother any further.

I have indeed extrapolated from the experiments as presented in femtography. I am not advocating any new physics. You should be able to answer the question easily enough without any further reference to any of my posts:

What would the sensors register if the camera or cameras were placed at the end of the trajectory, instead of on the side?

That is the only relevant question, the rest is presentation details that may or may not be important.

I’d tell you a chemistry joke but I probably wouldn’t get a reaction.’

‘I’d tell you a joke about sodium but you probably wouldn’t get it.’
‘Try me,’
‘Na.

It's the OP who has read about this interesting experiment, and extrapolated some unjustified conclusions about being able to control individual photons — fishfry

This is a very narrow reading of my posts. Maybe you should take the videos where one or more objects are gradually illuminated, and imagine that the camera is not on the side as it is on all the videos but at the end of the path of the beam. Nothing needs to be changed further to the experiments, and instead of my racers arriving all at once or not, the question becomes:

Will we see the whole scene enlightened at once, or will we see each object getting lit by the beam as the beam (or rather pulse) progresses?

http://web.media.mit.edu/~raskar/trillionfps/

Femtography and the Foundations of Physical Science

Scientists take some ideas as being beyond any doubt, and they use these ideas to build their cosmological theories. Some of these ideas are:

1) Light goes on indefinitely
2) The universe is expanding
3) When we look through a telescope, we are seeing the past.

These ideas, and more, support each other and give each other meaning. They are all inextricably linked with each other and an attack on one is an attack on all,

Femtography could give an empirical basis to all those beliefs, and silence any dissenting voice.

Or it could usher a revolutionary era in physical science.

I would propose the following experiment:

Have a laser emit a pulse of a few nano or picoseconds in a vacuum.
The pulse will remain of course invisible, except maybe for the reflections on the walls of the container. So maybe it should take place in empty space.

Following the same methods advocated by femtography, one or more sensors should be placed in the path of the pulse some distance away.

Those sensors should only be turned on after the laser has stopped emitting.

As I see it, there are only two possibilities:

1) The pulse is registered, and I would consider that as a confirmation of the contemporary physical theories where light is concerned.

2) The pulse does not register, and then all bets are open.

‘A man asked his friend, “Want to hear a joke about butter?” His friend was like, “Sure.” The man thought about it then changed his mind. “Nah, I butter not tell you. You might spread it.” (Helen Harper)

(f) the Earth is destroyed to make way for a hyperspace bypass. — Michael

I think that explains life, the universe and everything.

I think we can now safely close the discussion.

There may be a very simple argument to prove me wrong. It would go like this:

Two dots appear as two distinct dots from a distance smaller than or equal to x. If the distance is larger the two dots will appear as one.

To see them as two distinct dots from a larger distance, those two dots will have to be farther from each other than they were. The extra distance between them takes more time of course.

Now all you have to prove is that the distance between the moon and Jupiter was the same at all Earth positions on the orbit path. But I wonder if that is possible. More importantly whether it were possible in Rømer's time.

An extra problem is that it really sounds like begging the question: how can you determine that the distance between the two dots has (not) changed?

Anyway, good luck to you.

If you want to prove me wrong, and I am not saying I cannot be, you should concentrate on this alternative solution and exclude it from consideration, whether Rømer did it or not.

In other words, if you can prove that distance in no way could affect the perception of the moon as a distinct object from Jupiter, then you will have proven this alternative wrong, and by extension my whole argumentation.

I wish I could agree with you because it makes a lot of sense.

I am afraid that my interpretation is quite different.

You are still trying to justify the accuracy of the method in calculating the speed of light, while I consider it a secondary, technical problem. Which by the way you describe beautifully.

There are, or at least were, two possible solutions, or more, to the question as to why the moon appeared later when the distance was larger, and sooner when the distance was shorter.

The first alternative, the one chosen by Rømer, and since then, by everybody, is that light needs time to reach us. Once you assume that this is the right solution, the rest is simple math.

The second alternative, the one I presented, even if it is not necessarily the right solution, could not be excluded. According to that alternative, our perception of two distinct objects as distinct from each other depends on the distance between us and those objects. The farther the objects are the longer it takes for moving objects to appear distinct to us. The closer they are, the easier it is.

There may be other logically possible solutions, but that is the only one I could think of.

The discussion should not focus on which of those alternatives is now considered as the right one, but on the fact that Rømer in his time had no justification in choosing one and discarding the other.

the discussion with both of you on this thread has come to an end. Why prolong it unnecessarily? We all know where each of us stands.

if you need to ask you don't need to answer.

I am curious what you will make out of this

put your money where you mouth is, kiddo.

So yes, let's agree to disagree on whether you're right and all the astronomers and physicists are wrong. — Michael Ossipoff

I am really disappointed in your analytic insight. The discussion is not about the speed of light, nor about astronomy. It is about the historical validity of Rømer's argumentation.

Trying to fault my logic through facts is really irrelevant, and I am sure you already know that.

I am not judging facts, I am judging an argumentation.

That is where our interpretations diverge. I say that his idea was not the only possibility, and he never gave any reason why it should be.

I will not repeat my arguments, it would be a waste of time for all of us.

Let us then agree to disagree. Unless you prefer insults and name calling.

Twenty minutes later he comes back, walks over to the table, sits down, and says “blow job.” — T Clark

I was half expecting do be do be do, but this is much better! :)

You'd be able to understand my description of Roemer's method, but you won't look past your pre-formed belief that you have the truth, and all the astronomers and physicists are wrong. — Michael Ossipoff

Too bad you have changed your style in favor of polemics. So be it.

Not, it is not a matter of how precise measurements are. In fact, it does not concern measurement at all, except in asking the question:

What are we exactly measuring?

You assume, like everybody else, that it is the speed of light. Once you accept this assumption any inexactitude becomes historically irrelevant. It becomes solely a matter of progress in the measurement process.

I am asking of you to do one step back, before you decide that it is light speed that it is being measured.

When you do that you can ask yourself again: what am I measuring?

What happens when I observe an event from position p1, and then observe the same event from p2?

If you take the way your observation takes place as irrelevant. That is, if you do not doubt an instant that when you see the event happening, it is happening not at that moment but because light needs time to reach you and make you see it. Then you have already assumed that which you wanted to prove, and the only thing that rests is count the seconds or the minutes between one event and the other.

So, in fact, I am saying that Rømer had already decided for himself that it takes time for events to reach us, and the matter of calculations was then easily resolved.

Apparently, I am unable to convince you that that was an illegitimate jump in his reasoning. That is why we keep going back and forth without anyone of us convincing the other.

For the last time, once you accept the main idea, that is now a given in modern science, then there is no reason to doubt the validity of Rømer's argument.

But you must remember that in his time, that was not obvious and had to be proven. Well, my claim is that he did not, and simply assumed it, then presented calculations and made it sound scientific.

Whether he was proven right afterwards, or not, is irrelevant. What matters is, was his argumentation valid when he made it?

My answer is NO!

You realise that this is not an argument? — Banno

I am saying that Rømer did not have an argument.

You still do not understand my point.

If I am right, you are, in such a situation, not measuring the speed of light, but the moment the moon appears or disappears for you.

All you can say is that when you are at p1, you see it at t1, and when you are at p2, you see it at t2. You cannot draw any conclusion about light.

That is what, I suppose, makes my analysis so difficult to accept.

You apparently have trouble grasping my objection. There is no reason for me to reject these observations, I am not an astronomer.

What we are talking about is the epistemological value of those observations.

To put it as clearly as I am able:

1) You see the moon appear at time t1 while you are at positon p1 of the orbit.
2) you see the moon appear at time t2 while you are at position p2 of the orbit.

@Michael Ossipoff made it clear to me that I was right in doubting the validity of my first version in which I doubted whether it was possible to assume a common clock. So, looking at the times and trying to falsify Rømer's argumentation was wrong.

My objection concerns the fact of the observations themselves.
When you see the moon at t1p1, that is an observation that is determined by the resolution of your device and the distance to the moon.
That distance determines the moment at which the moon becomes distinguishable from Jupiter as a singular object.

The longer the distance from Jupiter, the longer it will take for Jupiter and the moon to become distinguishable.

My objection may be be invalid concerning modern telescopes. Maybe modern optical technology has made distance irrelevant. I would not know and defer to the experts on that point.

What is certain is that this was not the case in the 17th century, and that is why I dare claim that Rømer's argument is not the proof everybody thinks it is.

I would like to sum up the different empirical issues that I have tried to handle concerning light theory.
I have always found it regrettable that my critics concentrated on abstract theories and general principles instead of of looking at the empirical issues I presented.
I must of course start with @VagabondSpectre's judgment, and will end with a challenge of my own that is still unanswered.

Nobody is going to try and debug your poorly executed experiments...
https://thephilosophyforum.com/discussion/comment/114189

Where is Poisson when you need him?
https://thephilosophyforum.com/discussion/comment/112967
Why isn't the center of every image or picture always as bright, whatever the aperture?

Vibrations and Visibility
https://thephilosophyforum.com/discussion/comment/114796
Imagine bright rays shining vertically, and others shining horizontally, wouldn't you face the same bright rectangle in both cases?

Are Black and White Colors?
https://thephilosophyforum.com/discussion/comment/114530
But then, what would happen if you used a non-white screen?


Inside the Camera obscura (2)
https://thephilosophyforum.com/discussion/comment/114394
Light has to go through splits that are separated by opaque bands, We see bright and dark spots. Why should it surprise us?

The Double Slit Experiment
https://thephilosophyforum.com/discussion/2126/the-double-slit-experiment
Where interference patterns as well as so-called Newton rings appear in pictures of a simple laser beam, belieing the idea that they are special effects due to the wave nature oflight.

Femtography
https://thephilosophyforum.com/discussion/2132/femtography/p1
Too bad, because such an experiment would shut me up once and for all. That is, if we are unable to see the light beam growing towards us.

A challenge Still Unanswered:
I have noticed that the arguments used against me are, as far as I can see, incompatible with the theory of light that is supposed to prove me wrong. I asked for links and references that would justify such an interpretation, but nothing has reached me.

you should take requests and charge people for it. :)

@MikeL

Sorry for this side show. I will refrain from further off-topic comments.

I like the drawing.

X-)

A young woman has been bedridden all week, nursing a mean cold. Sunday she feels somewhat better, even if her throat still aches, and she can barely speak above a whisper.
Still, she decides to go visit her best friend in town.
She knock at the door and the husband opens: is your wife home, she whispers?
The guy looks left and right and whispers back: no, come in, quickly!

In the Moroccan dialect "insured" and "from Syria" sound exactly the same.

A cop stops a biker and asks: is this motorcycle "insured"?
No, says the biker confused, from here, from Casablanca.

Amen.

As I said, i did my best. — Michael Ossipoff

and I appreciate it. Thank you.

nope. I am done with your ( you and the Friends) evasive maneuvers. Let us talk empirical facts instead of theoretical generalities.

In either case, there isn't any error in principle. — Michael Ossipoff

In this case I was right to discard my first argumentation, and concentrate on the perception of the (dis)appearance of the moon.

On this point, I am afraid, you have not changed my mind.

Again you do not understand my question. I do not care whether it is 7 or 70 minutes.

Maybe you should think about Einstein's thought experiment involving the synchronization of clocks. I am not saying relativity is involved at this level, I am just asking ( and remember, this is a discarded version), how times and clocks relates.