Genady

Thank you very much! Your review is very helpful. Both aspects - what the book offers and what it does not - are positive for me, because I am interested in ideas and fundamentals rather than in techniques. I am going to have this book, the 2023 edition, and will enjoy studying it. Cheers.

"... the whole numbers must at the same time be more numerous and equally numerous with the squares ..." Just wanted to note that the whole numbers can also be at the same time less numerous than the squares.

What is the nature of our existence? Assuming that our means humans', our existence has physical, chemical, biological, and social natures.

One of my favorites from the local bakery, which is called "Real Dutch Bakery", is Oberländer. It's a sourdough bread. I don't know if they do it exactly like in this recipe, but it looks similar: Oberländer Bread | Yeast and more (hefe-und-mehr.de) Two of my favorites of all times that I cannot get anywhere else in the world are New York bagels from Brooklyn and pita breads from Arabs in Bethlehem.

This is exactly my point. I love bread. But I never buy it in a supermarket. I get one or two kinds directly from a small local bakery.

That was one of my first "jobs" in my astronomy club, when I was about 9. To manually follow a star with a telescope for a long exposure picture.

We aren't evolved to eat rice, corn, potatoes, squash, banana, olives, cereal, sheep, cheese, ... Maybe we don't need to be evolved to eat something?

I think it's bad science. One can make a lot of other guesses on why they avoided the gap. For example, they knew that it is easier to stay on a flat surface.

"If he had only stuck to math he would not have gotten into trouble with the Pope. There's a lesson in there somewhere." Also, if he had only stuck to strength of materials he would not have gotten into trouble with the Pope. Galileo's Beam Experiment (lindahall.org)

Sorry. Too lazy to cancel.

I give you -1 for putting this thread in a Science forum. I promise to cancel this -1 if you can justify that.

As for gravitational time dilation of proton, it is about 1-3*10-39. This is dilation of 10-22 second over the age of the Universe.

How did they (the observers) know that they observed a fear of heights and not something else? Especially, it is strange because cats do not fear heights.

Then consider / compare binoculars. See e.g. here: How to choose binoculars for astronomy and skywatching | Space

Yes, perhaps. But also, how we define 'relativity', 'relationship', and 'objective' in this context.

I think that such a distinction is undefined. Can you clarify what you mean by "inborn or not"? Then why it's in the Ethics forum?

Keep the expectations low. Stars will be just dots, anyway. You will see more of them, and they will be brighter. You will see some details of the Solar system objects, such as rings of Saturn and other planets' satellites. These will be exhausted soon. Nothing like crisp and spectacular images one finds online.

Thank you for the correction.

What is the purpose?

So, you can "measure the increase in volume from inside the volume."

But the ruler is not a wavelength of a travelling photon. The ruler is defined locally. For example, like this: (Metre - Wikipedia) Such rulers do not expand. PS. I've picked that half a line because I saw it a pivot for the rest. It is relevant.

IOW, define metric. Exactly.

The ruler does not expand. The expansion is present on the distances of hundreds Mpc's. Expansion of space is a feature of homogenous isotropic space. But the physical space is not homogenous and isotropic. It has local areas of various densities of energy and momentum. They are sources of gravity, and they cause the spacetime to curve this way and that way, to shrink and to expand here and there with various rates. Only when all these local effects are averaged on the distances of hundreds Mpc's, the net effect of them becomes a uniform expansion of space.

And now?

You can say whatever you want about your pictures. But it is not how GR works. In GR, distances are determined via metric. Take two events in Minkowski spacetime, for example, events A and B: Which one is closer to 0?