Da Vinci certainly appears to be exploring the former. The latter was Einstein's great insight. I don't see much in the article to persuade me that da Vinci was equating gravity and acceleration in the way Einstein did, and so the title seems a little too suggestive.
I don't think that's quite what Whig history is. The Wikipedia article doesn't seem to imply that, either. If there was a "Tory history", I think this case would be more like that, as it presents a past figure as being more enlightened (while Whig history typically does the opposite in order to extol progress).
He was millennia ahead of his time, and I personally believe he had an understanding of physics but was existing in a time where the tools available to his understanding were what was lacking.
This guy predicted eddy-based hydrodynamic in the cardio vascular system before "human biology" was considered a science.
Look at da vinci's designs for the eddy-hydro-pump system...
Maybe he was a time traveling engineer who needed to plant seeds of knowledge in our past on this timeline to ensure advancement and growth of Humanity.
https://en.wikipedia.org/wiki/History_of_gravitational_theor...
That's an interesting article, including some challenges to Aristotle's views and gravity-related concepts introduced by Indian and Islamic scholars of the 6th - 12th century eras or so.
Isn't that a core problem with Wikipedia? I don't understand why its reputation on HN improved, a few years ago, from 'infotainment but a symbol of mis-/disinformation' to 'source of truth'.
This sounds like a gross misinterpretation of what Einstein said.
Einstein's great insight was that gravity defines inertial (i.e. non-accelerated) frames of reference. Put differently, in free fall you are not in an accelerated frame, despite what an outside observer on the surface of Earth might say. This is commonly abbreviated by "All massive bodies follow the same (inertial) trajectories in the presence of gravity, irrespective of their constitution", which is the Equivalence Principle.
What you are maybe referring to is what an observer experiences who stands still on the surface of a massive body: They can't free-fall, and so they're not in an inertial frame (= the thing defined by gravity) and thus actually accelerate upwards from the point of view of spacetime.
> we ... assume the complete physical equivalence of a gravitational field and a corresponding acceleration of the reference system
Thinking of the effect on speed of things falling down as acceleration (as opposed to constant), and even coming up with a formula, is already a bridge between these two things.
The insight of da Vinci’s here is anticipating Newton, not Einstein. And yes, this is already an accomplishment, but not the outlandish one the article would imply.
But the water droplets/sand particles do NOT form a straight line if you accelerate the jug. You have to decelerate the jug with exactly the right timing to form a straight line, not accelerate it. Nor do the beads in the Caltech video form a straight line, despite their dishonest attempt to arbitrarily impose a straight line on beads that are clearly not in a straight line.
In the second diagram, which is alleged to be an attempt to plot acceleration due to gravity to the position of an accelerating water jug, the values [0,1,2,4,8] are marked on the x-axis, and [0,-1,-2,-4,-8] on the y-axis. Da Vinci then plots lines from [0,-8] to the points (0,0),(1,0),(2,0),(4,0),(8,0). Doing so doesn't really establish any sort of relationship between accelerating jugs and acceleration due to gravity, even allowing for an incorrect equation of motion for an accelerating object.
Da Vinci spent most of his early career trying to sell military technology to potential patrons (largely if not completely unsuccessfully). One of the pieces of technologies he was trying to sell was a process for calculating improved artillery range tables (tables of elevation vs. range). He didn't manage to sell that either.
The second diagram is more easily interpreted as a doodle that makes an unsuccessful attempt to scry a relationship between elevation and range for artillery pieces.
All lines look straight if plotted on a log-scale and drawn with a thick enough marker.
https://www.goodreads.com/book/show/34684622-leonardo-da-vin...
I also came to appreciate some of the artwork and now I can look at the Mona Lisa and have my own thoughts on the work.
The existence of acceleration aspect may not have been novel, but measuring the rate seems to be the novel part
But Gravity powered clock mechanisms existed during Da Vinci's time. I believe.
"da" means "from", or in this sense "of". So just as you might say "Jesus of Nazareth" you say "Leonardo of Vinci".
You would never say something like "...and Of Nazareth said...", so likewise it's weird to say "da Vinci invented..."
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Edit: The quote above, and my original comment below, are wrong. The article is correct. Accelerating the jug at g will create a straight line.
Corrected acceleration model: https://scratch.mit.edu/projects/805927382/
Thank you hannasanarion for the correction.
Indeed, this can be thought of intuitively (though it is slightly counter-intuitive): as the article says, if the jug is moving at a constant speed, the drops will actually make a vertical line under the jug. This is because each drop will be move with the same horizontal speed as the jug.
A decelerating jug, as proposed above, would actually create a backwards line or curve. The drops at the bottom works actually be ahead of the jug.
An accelerating jug is the only way you can get the bottom drops behind the jug.
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My previous comment:
Indeed.
I was pretty sure this was correct, but wanted to model it to confirm. On a Chromebook right now, so Scratch was the easiest way to model and share:
Accelerating jug (cat): https://scratch.mit.edu/projects/805898350/
Decelerating jug: https://scratch.mit.edu/projects/805899100/
You can make a right triangle via either acceleration or deceleration at the same rate as gravity. However, you can only make an Isosceles Right Triangle with acceleration
Vertical position is a function of t^2. If you have constant horizontal velocity, you get a concave curve like this: https://www.wolframalpha.com/input?i=Y%3D-1x%5E2
Accelerating the horizontal velocity leads to a triangle like this: https://www.wolframalpha.com/input?i=Y%3D-x
You can see that here: https://demonstrations.wolfram.com/TrajectoryOfABomb/
At any time, the first bomb is always directly under the plane. This means all subsequent bombs will also be under the plane.
Years ago when I was really into [various philosophies] and [secret society]...
They stated that gravity actually pushes up but it is mass and movement that counteract gravity's push
it was the vibrations of cymatics and sound that could counter-act mass on gravity and take advantage of gravity pushing up... and this is how the ancients knew to move/manipulate matter in space...
This is what Tesla alludes to through 3/6/9 vibrations, and how Ed Skalnanin built the coral castle.
Its all about changing harmonious vibrations, and both Skalnanin and the Egyptions had interesting vibratory circular tools which are missing parts, but basincally from spinning them they could manipulate the vibratory frequency of matter such that their mass didnt effect gravity and took advantage of gravity's push...
So the idea was to think of mass as the inverse of gravity when the frequencies are not sync'd..
I know it science-fiction, but its fun to think about.
I think the more interesting effect to look at is centrifugal forces. I think that everything spins because a constant turning (warping) of space-time (gravity pushing) 'UP' is how mass stays 'co-herent' 'co-hesion'
Think of superconductive levitation. Slow the spin of an object "in-motion" and it can levitate...
What if rather than through temperature control on manipulating the rotation of Atoms, you could use sound to levitate objects.. (seen the frog levitating in ultra-sound...
The conspiracy idea is that it is mapped out in certain stone carvings for the frequency.
Like the Rose church, which has Cymatic [atterns carved into its walls, which tell you the frequencies used...
Think of how certain alloys are made under magnetic fields, and ceramics. Imaging forging an alloy under both a magnetic field & a cymatic frequency.
I love this conspiracy theory as its a great foundation to science-fiction writing as well.
When you are falling, you are feeling the air that is hitting you because it is not falling, causing the electron effect above, and your guts feel weird because your brain is noticing that nothing is pushing on them anymore.
Even when claims are made that he is "prescient", there has never been, nor will there ever be a functional "helicopter" that looks like Da Vinci's helicopter.
[1] How Leonardo da Vinci made a living from killing machines, https://theconversation.com/how-leonardo-da-vinci-made-a-liv...
[2] Leonardo’s War Machines – The Italian Genius May Have Deliberately Sabotaged His Own Designs, https://www.warhistoryonline.com/history/leonardos-war-machi...
No: it has no stabilising rotor. However, there could be a functional quadcopter using four of Da Vinci's aerial screws: https://www.cnet.com/science/this-drone-flies-using-da-vinci...
Imagine what they could have achieved if they have had access to modern tools, even "just" something like a graphing calculator[1].
[1]: I like https://www.desmos.com/calculator
There are thousands, maybe millions of people with genius-level intellect, all capable of being the next Leonardo or Einstein. Out of them only a small fraction grew up in the right environment, usually wealthy families, but that's still a lot of people. The next, and I think most important requirement are the tool needed to make the discovery, or even just to know that a discovery is to be made.
For example, if you don't have the tools needed to notice that the speed of light isn't infinite, special relativity makes no sense. General relativity requires even more tricky measurement, in fact it didn't came long after people noticed something was wrong with Newtonian mechanics.
Tools are in the general sense. Physical object like a computer or a good telescope, manufacturing techniques and even maths, think of the "shoulders of giants" thing.
So it would be more like giving the graphing calculator the genius it needs rather than going back in time and giving the genius a graphing calculator.
That seems extremely unlikely, but we won't find out for at least 1500 years.
Otherwise, as outlined in my previous comment, it does not make any sense.
Corrected model: https://scratch.mit.edu/projects/805927382/
I guess in terms of the big five, he was super-high in openness but no so high in conscientiousness. In today's world he would fit better because he could run an institute or a company.
Looking a little further into the article, I see it mentions a whig history of science that ignores failed theories and dead ends, and I would agree that this is not the same as attributing successful theories to people who probably did not hold them, though the latter does also tend to present science in 'march of progress' terms.
The idea that the Galileo in being the first to formalise an equation for precise calculation of acceleration was by extension the first in history to conceptualise that acceleration occurs at all is a severe infantalisation of all scientists who preceded him.
Extending this: the Whig story on contemporary science (sp. as it affects policy) is that this is the best science because scientists have been improving it forever, while the conservative story is that maybe the scientists are wrong now, they’ve so often been wrong in the past.
states it more clearly
"... a characteristic of that kind of historical writing in which the author seeks antecedents of present-day institutions or ideas in earlier historical periods. This kind of anachronism is considered to be a form of Whig history ..."