Genady

Not necessarily. Imagine a 3D sphere with the gravitating mass in the center and the gravitational field lines going from there. The force goes inversely proportional to the distance squared. Now cut the sphere in the middle and look at the cross section. This gives you the 2D image of the field. The force still goes inversely proportional to the distance squared.

Because physical 2D world is a pure fantasy, I guess one can make up any 2D physics they like. However, they still cannot make up mathematics.

When calculating gravitational potential energy near the Earth surface, where the gravitational acceleration g is almost constant, we choose it to be 0 on the floor and the energy is mgh where h is height above the floor. It changes sign, too. And it works just fine.

In fact, you can get a nice formula in your 2D case as well: since adding a constant to energy doesn't change anything, you can simply remove the ln(L) part and get the general equation for absolute value for any distance, GMm*ln(d). Is there a magnetic field in 2D?

This list of physical and technical difficulties and potential points of failure can go on and on. It seems that self-replication algorithm is an easy part - it is all the rest that is difficult or impossible. Self-replication doesn't help in solving other issues.

The value calculated from infinity is as absolute as values calculated from any other choice of distance. You can choose the energy being 0 at some finite distance L. Then in 3D, the general equation for absolute value for any distance is GMm(1/L-1/d). In 2D, it would be GMm*ln(d/L). They all are absolute values. You can choose L to be 1 km, 1 parsec, diameter of the Milky Way galaxy, radius of the observable universe, whatever. It doesn't matter because in all physical calculations the constant L will cancel out. The difference between the formulas for 3D and for 2D is that the former allows you to choose L being infinity and to get a nicer formula without L to start with, since it will cancel anyway, -GMm/d, while in 2D you can't do this, although it will cancel there as well.

You don't have to integrate to infinity. You can choose anything convenient for your 0 energy and calculate from it. The only meaningful value (in Newtonian world) is energy difference, not its absolute value.

A few minutes after this^^^ topic has appeared on my screen an ad showed up, "¿Jesús resucitó de la muerte? Jesús enseñó que la vida no termina después de la muerte física." Coincidence? God? AI?

Also e.g. ants workers / soldiers die protecting the Queen.

Why then wouldn't you write to these scientists and ask them directly for the missing explanations? BTW, here is what Neil deGrasse Tyson had to say about how fine the universe is tuned for life. Spoiler: "stupid design."

Maybe you shouldn't look into youtube videos as representation of scientific thinking?

This picture could be an illustration in my other thread, about the right handed helices of wire black corals. But the lionfish sitting on the helix' axis at 140', 43 m has requested to be here:

I know, let's use German, erstellen. Sounds just like eigen and gedanken.

You mean, we shouldn't say that particles are created? shouldn't call 'a+' a creation operator?

I should've put the last statement in that post in parentheses, like this: (The inflation model solves this one.) I wanted to bring another example of a fine-tuning problem in physics. Inflation is interesting in this respect as a way of eliminating a need of fine-tuning dynamically, in principle. One of possible ways.

I couldn't say it better. +1 Another fine-tuning problem, in cosmology, is related to the flatness problem, i.e. the degree of the current flatness of the universe requires incredible closeness of the initial energy density to a critical value at the start of the universe expansion. The inflation model solves this one.

I think that most physicists think, this IS a valid option. Many think that one day we'll be able to derive Lambda and other numbers which today we need to put in "by hand", from some first principles. So, they are what they are because they cannot be anything else, any other numbers will lead to some inconsistencies.

That's right. Why do you expect "there being a problem?"

You said some time back that "it has to do with the universe existing the way that it does is too improbable". I think that I didn't make it clear then, so I do now: I don't think that it has to do with the universe being improbable, but rather with it having improbable value of some parameter, e.g. Lambda. I said then that all universes have the same probability to exist, but the values of Lambda don't have the same probability. That's why Lambda is in the picture. I do not compare probabilities of different universes. They are equal. I compare probabilities of having various Lambdas. These are not equal.

LOL

I think we are saying the same thing, don't we?

Again, it is essentially the same solution, i.e. there are multitude of possibilities and the one you are in just one of them that happened to fit you. Multitude of sperm, multitude of environments on Earth, multitude of planets, multitude of universes. The model is the same: no fine tuning is required if there are many possibilities and some of them just happened to fit your existence.

This is all correct. However, did you notice that the picture of the "fine tuned" Sahara in the example above is essentially the same as the multiverse one, i.e. there are many different environments with various conditions in them and the bacteria exist where and when the conditions are right for them? (DISCLAIMER: I am NOT a proponent of the multiverse model, just an objective - to the best of my abilities - observer.)

In this picture, a lionfish and a sea urchin share a rock for food and shelter:

The Lambda was what led to the comparison. It was not chosen for comparison. What is your reason for comparison?