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Searching [ linux print to pdf ] gives plenty of results.

Brother printers can print direct from USB memory, but only certain formats are supported.

e.g. https://help.brother-usa.com/app/answers/detail/a_id/76908/~/how-do-i-print-documents-or-data-directly-from-a-usb-flash-drive-or-digital

To print the odt files, install Libre Office on a computer connected to the printer.

If no PC is connected, try KJW's suggestion to print to pdf, then stick that in the printer.

Could you just use a servo?

If it doesn't need to be too strong, you might find a cheap Arduino kit with a servo.

Then easy to program, for how much sweep you want.

This kind of thing (skip right to near the end to see in action): 

It's very normal for a forum to have a time limit on the ability to edit a post.

You could just re-post, I guess. (Here, not a new thread.)

Disclaimer: I am not a moderator of this forum, I have no authority and am not pretending to have any.

1 hour ago, mar_mar said:

Animal's brain differs from human's.

They don't know that something is "red" or "green".

It's like different language. You see foreign letters, but you don't know what they mean. Like hieroglyph. For Chinese they have meaning, and you don't know one, for example.

...

I know from my own plum tree that birds can tell the difference between a green unripe plum and a red ripe one.

Bees can find flowers.

That's not putting any emotion on the birds and the bees, nor is it anthropomorphism to say: they can certainly detect and distinguish colours.

Why does it matter to you that they don't have a language with which to name these things, or a brain like ours to "know" them?

I sometime find it hard to do what I would like when replying to a post, due to the WYSIWYG editor.

I've not been able to find a non-WYSIWYG mode, e.g. where you'd see the tags used by the site to mark quotes and such.

Does that exist? If so, what's "the button" look like?

You seem to be shifting the goal posts.

https://www.abc.net.au/science/articles/2005/03/28/1332458.htm#:~:text=Australian marsupials can see in,from primates to do so.

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The researchers looked at cone cells at the top of the retina and the rear of the animals' eyes and found three distinct cone types that enable full colour vision.

Nobody is saying "blue makes kangaroos sad", or "red makes kangaroos angry", or that they have a special word for their favourite green, when their food is most edible.

But you started out saying colour only exists in human minds. It's been pointed out that light has different measurable frequencies and it can be show that different animals can perceive them. Just look at the green plants that make yellow (etc) flowers to help the pollinators find them (sometimes more about UV light) - even many insects can see some kind of difference.

If your point is just that we shouldn't anthropomorphise animal colour vision, that's fine but it's NOT anthropomorphic to study (and show) their colour vision exists.

3 minutes ago, mar_mar said:

One can do quantitative measurements, like how far a kangaroo can jump, but one can't do measurements of an emotion.

What do you say to the various experiments done that show (some) animals can tell one colour from another?

I read the article, and didn't see anything in it about whether animals can distinguish colours.

Then I realised, there was some doubt about what caused the female kangaroos' death.

It became obvious: as the kanagroo can't distinguish colours (so says mar_mar), it hopped into a tree it hadn't noticed.

I don't think that's a valid way of looking at it as you neglect to include where the $6 comes from.

It's from income (e.g. the money you spent minus the tax), and isn't infinite.

Start with the $106 that you got from somewhere. You buy that $100 thing and $6 goes to tax.

In your next step, that 2nd person starts with the $100 they got from you. They might buy something for $94.50 + $5.50 going to tax.

The third person spends that $94.50 as $89.50 with $5.00 going to tax.

... it's not generating infinite tax. All that taxed money still had to come from income somewhere.

(I'm tired, I'm making up the specific numbers.)

4 hours ago, mar_mar said:

I think that when there were no humans, there were no observation, or I'd say awareness of the world. Do plants know that they reflect '555 nanometer wavelength light'? And in the experiment with two slits we saw that observation makes electrons behave like particle. If I understood this experiment correctly. 

First thing to make clear: pop science, and bad science fiction, makes a big deal of the "observation" part of the double slit experiment but that doesn't mean anything like an intelligent observer is needed. It's just about interactions of things. No consciousness needed.

And no, plants don't "know" they reflect light. So what? Why does that matter?

Reflected light from one (unconscious unaware) object may hit another (unconscious unaware) object. The specifics of that light (wavelength, intensity, ...) can mean different effects occur, e.g. different amount of heat added to the second object. The second object, perhaps a rock, doesn't call the light "green" or "banana". Why does that matter to you?

(When you close your eyes, does your coffee cup vanish? Does it become non-real, only to somehow reappear when you open your eyes again?

In the centre of a large forest, that no human has ever been to - are there trees? Or just a formless void because nobody has looked at it? If someone did look, would fully-formed trees suddenly appear?)

Before humans existed, there were plants.

Are you saying those plants would not have reflected 555 nanometer wavelength light - just because there was no one there to give a name for what they perceive?

10 hours ago, Bjarne-7 said:

... The key word here is "elastic space" which, in terms of understanding, actually does not deviate very much from the previous perception we have of the deformable property of space. So "merely" a "play" with expressions seems to give the theory of relativity "new properties" which may become necessary in the long run. ...

You should talk to this guy, who had "Space must have some kind of elastic nature woven together with matter" as an important part of his theory: 

I know what I say when I hit my thumb with a hammer.

The example I find most amusing is the guy who posts his "alternate" hypothesis (which I won't name here) in the speculations section of a forum I read. He's been posting "conversations" he's had with ChatGPT about his hypothesis. He seems to think it gives some weight to his argument, that the "AI" understands his claims and can discuss them rationally. But of course all it's doing is combining what it's trawled off the internet - from the guy posting about his hypothesis - with his questions. A big echo chamber.

Myself, I use ChatGPT sometimes to get code examples for my work (as a programmer). The way it essentially combines different sources together to give a complete answer is sometimes very very useful, better than StackOverflow for example. But other times it's given answers that are just plain wrong. It doesn't know, it's just mashed together bits of information that seemed to go together. One example was when an "answer" turned out to rely on a library that simply didn't exist. Maybe it did once, when some bit of information got scraped off some site that led to that answer. Sometimes I can tell it it's wrong or missed a detail, and it "apologises" and posts something better. Sometimes there's no help.

So all I can say: the day an AI gets directly wired to the nuclear deterrent so it can quickly identify and respond to a first strike ... that's the day we are all doomed.

11 hours ago, lidal said:

...

You don't seem to understand the whole point because you are busy searching the internet to find other sites where I have posted the same topic. 

I suspected and abandoned the relativistic approach from the beginning. I started with a classical approach and found a result that can divide physicists. Will the two pulses in the thought experiment arrive simultaneously or not? 

...

Ha! I'm not wasting my time searching for your spam; I happened to see it on two sites I visit most days.

There is absolutely no reason why the two pulses from S₁ and S₂ can't arrive at D simultaneously. This is not controversial at all. Further, if the ship is inertial and D is exactly between S₁ and S₂ that would mean the pulses were emitted simultaneously too - according to an inertial frame where the ship is not moving.

The real question is the view from a different inertial frame, i.e. from a frame moving according to the ship (or for which the ship is moving).

From that other frame, the simultaneous arrival is not in question. (The common example is: what if D triggers a bomb? The bomb either explodes or it doesn't, nobody can disagree.)

But according to that other frame, do S₁ and S₂ emit in sync? The answer has to be no, because the speed of light is not infinite, and D is moving towards one pulse and away from the other. The pulses have to be emitted at different times to arrive at D together.

All you have done is reverse the classic train/embankment experiment ( https://www.marxists.org/reference/archive/einstein/works/1910s/relative/ch09.htm ). Your S₁ and S₂ are the lightening strikes, and D is the observer in the middle of the train. The difference, is the strikes are stipulated to be simultaneous in the embankment frame, and the question is whether they are also simultaneous in the train frame; you have provided the vice versa - stipulating the strikes to be simultaneous in the train frame.

Where you go wrong is seen in this one line in your OP:

"It should be noted that, according to special relativity, the clocks synchronized by this procedure will be in synch. However, from experience we know that the clocks will be out of synch. Therefore, we know that the relativistic procedure is wrong, based on experience."

With the "we know" and "experience" bits you show you are assuming that there's one real truth to simultaneity, and for some reason it's not the ship that's right.

Essentially your "proof" that relativity is wrong is to assume relativity is wrong.

99% of "issues" in relativity come down to the relativity of simultaneity.

That observers inside and outside the ship can agree the light pulses reach the detector at the same time, yet can disagree that S₁ and S₂ emit the pulses at the same time, is well understood.

There's no issue here except ignoring the relativity of simultaneity.

(Disclaimer: 99% of statistics are made up)

Oh! And then another cross reference: https://forum.cosmoquest.org/forum/the-proving-grounds/against-the-mainstream/3722813-a-disproof-of-the-principle-and-theory-of-relativity

10 hours ago, phillip1882 said:

no its velocity, you can experience this with your car, when you turn your thrown to the side some. clearly force is being applied.

Do astronauts in the ISS feel themselves thrown to the side of the station?

Cross reference: https://www.thenakedscientists.com/forum/index.php?topic=86571

Instead of ASCII, use EBCDIC.

And try Pi in base 9 instead of base 10.

Does your numerology still make anything you recognise?

I make a lot of curries so it's the spices that get cooked first.

The current math for gravity and orbits (Kepler, Newton, Einstein, ...) works very well, and does not show evidence of these "grooves".

Do you have math, to apply to the orbits of things, that shows they get positioned in "grooves"? e.g. the idea of these "grooves" implies certain discrete distances from the object orbited.

I'd also point out that orbits are generally elliptical, with an apogee and perigee. Multiple things in orbit around the same central thing* (e.g. the eight planets and our sun) do not have ellipses that coincide - the direction from the sun of their apogee and perigee are not the same; they don't indicate being in "grooves" that follow any kind of pattern.

(* that's a simplification for now.)

Elves.

The chance of someone who has no idea about current theories of abiogenesis correctly calculating the "probability of life" is approximately zero.

Makes me think of Dire Straits, Industrial Disease:

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...
Two men say they're Jesus, one of them must be wrong
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