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Humans can detect single photons with their eyes! https://www.nature.com/articles/ncomms12172

Thanks for the link, this is sick

In the 1500s, it might just as well be impossible to fly a spaceship to the outer edge of the solar system to confirm heliocentrism without doubt as it is right now to build a solar system sized detector to look for the graviton.

Geocentric coordinates are easily observable; just look at the sunrise and sunset. And if you zoom out even more and look at the galaxy, heliocentric coordinates become unreasonable.

And at the speed at which the solar system is orbiting the galaxy, I don't know that it would even look much like like the planets are orbiting the sun.

In fact the planets aren't orbiting the sun. They're orbiting the galactic center, and the sun just happens to disturb their orbits a bit: https://youtu.be/0jHsq36_NTU?si=VbRsJ_SyA7JK4TD8&t=53

Does it mean we are surfing our galaxy? I mean we are not in the same exact location any second-lapsed?

> Hence I feel heliocentrism is simply an observable fact.

It isn't. You can easily define a coordinate system for the universe in which the earth is the center.

Heliocentrism just makes some approximate computations easier because the sun is so heavy. Thus in heliocentrism, the orbits of the planets are approximately ellipses (near-circles) around the sun, while in a geocentric model, the orbits have more complicated shapes.

Nevertheless (to explicare "approximate" even in the Newtonian gravity model (i.e. not Einsteinian gravity)) be aware that even in the heliocentric coordinate system the earth (and the other planets) don't move along an elliptical (near-circular) orbit around the sun, but both the sun and the planet move around a common center which is near to the sun.

> There is no sane way to put the earth in the center once you do that. [...] Hence I feel heliocentrism is simply an observable fact. It's not a mathematical convenience. It's a fact you can see with a camera. The relativism or perspective argument is irrelevant because as we established you have to be very unreasonable to describe a picture of a huge ass sun that hardly moves with small planets zooming around it as earth centric.

Modern physics really is about that there is no preferred coordinate system: this manifests itself in the fact that conserved quantities can be derived via Noether's theorem from such symmetries in the natural laws. There is just a choice of a coordinate system which in our solar system makes computations easier.

>both the sun and the planet move around a common center which is near to the sun.

Within the sun, with one exception.

> Within the sun, with one exception.

OK, I admit that I never did the actual calculations, but only knew this property of the formulas. :-)

> The difference with the Copernican stuff is that you can fly a satellite (e.g. Voyager) to the edge of the solar system, look back, and see the planets orbiting the sun.

Or you can put the satellite in the back of a truck and back the truck out of your garage and see the sun orbiting the earth. Yet it remains sane to put anywhere in the center depending on your context.

If you have a reasonable grasp of Newtonian gravity you would also be unable to conclude that. A wrestler flailing a skinny guy around, from the POV of the skinny guy, is still definitely not the skinny guy flailing the wrestler about. I don't see what's to argue here. Given all facts, then there is no POV that results in the conclusion the sun goes round the earth. Just like how there's no placement of the camera that results in you claiming I'm pushing the earth away.

I agree with the example of human agents because we can acknowledge concepts like will, choice, agency, etc. But none of those ideas are present in Newton's laws of motions.

Will, choice, and agency are unnecessary for explaining the example. It can be described simply by the forces exerted. The locations of the observers or sensing equipment matter little in this case, though they do become problematic when attempting discern whether heliocentric model fits unaided observations from a planetary surface.

Am I wrong to think that because equal and opposite forces are always present, names have to be given to phenomena that are not present in the formal math itself?

> Yet it is very successful in all its predictions. So obviously the Popperian "falsifiability" is too simple a criteria for science.

Those two sentences contradict each other. If something unobservable implies some observable, i.e. predictable, consequences, then falsifying these predictions would also falsify the unobservable antecedents.

The hidden variable/better (unknown) alternative theory problem is what he is referring to.

Newtonian Mechanics are falsifiable, but no one could figure out an example that actually did so, until roughly when the orbit of Mercury was fully observed.

Then it was obvious something was missing.

Is there the equivalent for quarks? Or not?

We can't even see an electron. But we can see the effect of a beam of electrons on a low-pressure gas quite easily.

We can't even see a table. We can only see the nerve impulses resulting from the photons resulting from the sunlight bouncing off the table.

A computer can't play sound either, it can only send bits to a DAC.

That is true. I'm not arguing for that standpoint, but it works perfectly fine for all classical matters and has been since Descartes.

I think in a common sense way you do get what I mean though when I say it is obvious that when we see two billiard balls colliding we know it but when think of electrons colliding it is only indirectly through whatever happens after the collision, never the process itself.

We saw the things that were easy to see long ago. Now we're seeing the things that are harder to see. That is, of course, harder, and more complicated, and only gets worse as we probe deeper, with more and more indirection, but I think all the stuff we are seeing has a pretty good grounding so far that it's actually something we are seeing indirectly and not a model artifact, at least until you get to quarks and gravitational waves, and we definitely can't see the strings of string theory.