joigus

Not everything that's useful or meaningful as an average must have a valid thermodynamic definition. The average receding speed of the galaxies is increasing, yet the universe is not a thermodynamic system. The concept of temperature that's used in these atmospheric models is more akin to the concept of temperature in the heat equation. It is not the thermodynamic concept of temperature but for small cells of material that have a definite specific heat. Do you suggest the Earth's atmosphere does not have a useful concept of specific heat?

The genetic code is not fixed. It suffers genetic drift, mutations; some good, some bad, some neutral. And for about three billion years most anything that lived on Earth were bacteria and archaea, or similar. Where was our genetic code written all that time? Genetic code is not a fixed thing. Bear in mind, the rebound, if you prefer that term, goes to about a billion K degrees. Never mind collapse is not reached. What nucleotide can survive that? EM signals? Radiation in the universe doesn't hold information. In fact, in cosmological calculations, the entropy of the universe (the disorder) is about the number of photons. Crystals can hold information, not radiation.

The Bohr model is a quantum mechanical (not classical) model of sorts. You can get a good fit for the dynamics of the ground state for the hydrogen atom with semi-classical arguments. But the "centrifugal force" is supplied by uncertainty momentum. That's not really a "force." You can actually calculate quite a good approximation to the ground-state energy by means of HUP. But that's as far as it goes with half-classical arguments AFAIK. You must use quantum mechanics to solve quantum mechanical problems. I need more time to look at the previous arguments. That's all I can say now. Swansont can handle it perfectly.

@molbol2000, what do Cossacks have to do with P=NP? Give it a rest or open a new thread, would be my suggestion.

I think ALL is American: https://americanlacrosseleague.com/ Are the sources intelligent? is another question.

I think evidence is that life did arise. Complex life comes from much, much simpler life. Why would beings from another cosmic cycle send seeds in the form of amino-acids and simple nucleotides, when these can be formed from simpler substances? --Miller-Urey experiment and others. And how would these molecules survive a re-collapsing universe and a new big-bang?

No way to go off-topic, as the topic is ALL.

All is clear now.

Torques can cancel each other, kinetic energy can cancel potential energy, but kinetic energies can never cancel each other. Kinetic energy is positive by definition. Had you accepted my discussion in terms of rigid bodies, you would have seen that very clearly from first principles. For a partition into different points i of a rigid body in an inertial frame it has the form, \[\frac{1}{2}\sum_{i}m_{i}\left(\boldsymbol{V}+\boldsymbol{\omega}\wedge\boldsymbol{r}_{i}\right)^{2}\] which is always positive. After all, the kinetic energy is a sum of contributions (1/2)mv2, which is always positive.

You already said. Sorry.

Glycine has been found in asteroids too. It's the simplest amino acid. https://www.newscientist.com/article/dn17628-found-first-amino-acid-on-a-comet/

And at 90º "steepness" the drive would go to zero, because cos(90º) = 0. Ergo, no drive. Maths saves you a lot of thinking work. Maths are by nature non-intuitive perhaps, but once you learn them, they overcome most all flaws coming from our intuition. You can autopilot most of the time. But you've been one of the nicest, most civil speculators in these forums. For that, I thank you. The sad thing about this is, IMHO, that had you taken the criticism, maybe there would be an idea behind worth considering (by using frictionless superconductors, high "steepness" combined, who knows.) In the way of an efficient drive mechanism, rather that spontaneous drive, which is a physical impossibility. Ditto. I can't add more reactions today. I would need some action.

Just curious, @michel123456. Can you explain to me, so that I can see clearly that you understand, what synchronizing clocks mean? Please add some explanation of how observers (both in the same inertial frame and in different ones) synchronize their clocks. There is a reason why Einstein took pains to define very clearly this concept both in his papers and his popular books from the start. All observers, no matter what their state of inertial motion, must agree on one event as the origin of coordinates for space and time. That way, all transformations become linear and homogeneous. As Markus says: (My emphasis.) Otherwise you're working with affine transformations in space-time and the discussion becomes an unwholesome indigestible mess, if not mathematically, conceptually at least. And if not for others, at least for me. Sorry for the extra work that I'm giving you. I'm following the conversation from a distance, and I need some precautions in order not to turn mad. I won't participate much, I promise. If other users don't need this, it's OK with me. I'll try to keep up as best I can.

You make a good point here, but there are other factors. I can imagine no epoch in human evolution in which planning for the future, interpreting other people's intentions, guessing the best solution to a domestic problem --all of which is achieved mainly through language-- did not play a major role in women's lives. It is generally assumed that high-brow intellectual activity was what led to developing big (energetically costly) brains in humans. But the big pressure, the day-to-day strain on the brain to be able to develop more sophisticated cognitive abilities, is social, not inventive. That's what most anthropologists say. I may be able to provide more info about it later. It's been estimated that the main focus, by and large, of human language throughout the day is gossip, not the realm of 'big ideas.' And that goes for women and men alike.

This is known to be false. https://www.nasa.gov/pdf/64249main_ffs_factsheets_hbp_atrophy.pdf https://aging.ufl.edu/files/2011/01/deconditioning_campbell.pdf

Exactly. A person with few glicolytic fibers, a person whose body cannot synthesize myoglobin properly, etc. But also a person who doesn't exercise properly. The women that you're showing in the video --I haven't watched it either-- both are genetically conditioned to be that way, and have exercised to be that way. So it's a combination of both factors. Having a certain genetic make-up favours you being more muscular, but it doesn't determine it.

You've read a tad too much into what I've said. Some conditions are necessary. Other conditions are sufficient. Still other are necessary and sufficient (those are the terms in which you seem to be thinking.) A further category is when conditions are neither necessary nor sufficient: They are statistically correlating conditions. You say genetics determines what you are. I say genetics is affects what you are. See the difference?

Probably. And probably comes from a very ancient obsession with fertility. Hunter-gatherer societies were thin on the ground. And they needed manpower as any other. In northern Spain there is a Solutrean cave in which lots of vulvas are depicted. And fertility statuettes all across Europe. I don't think the motivation for that was ancient pornography.

It's a snowball phenomenon. And well known. And all evidence contrary to OP's premise. This is a very interesting conversation, but it's spilling over into wider aspects of anthropology.

Well, nomads are a bit of an exception. They are more pastoralists than agriculturalists. But they depend on agricultural societies to obtain the grain. Or move for pastures new, which leads to waging war again, when there are pastoralist agricultural societies claiming the land. Whether these and other similar societies used the bow and arrow is secondary. Agriculture brings conflict on account of claiming the land for yourself, and thereby war, which was the point. Yes. Agriculture is known to result in larger families. That's part of the equation. So we don't have 10,000 years of less war. It's just the opposite.

By the way, all the Bactria-Margiana area is full with evidence that these societies were agricultural, and also were very military-minded. They had to move because their rivers changed their courses. And conquered new land, south-east of Andronovo. According to Viktor Sarianidi.

Of course they're found in Andronovo. They're found in the Sahara too. And they made their way to America through the Bering Strait. It's one of the oldest techniques that comes from hunting and has been used on and off in warfare. You don't think it's true that I mentioned bows and arrows in connection with hunter-gatherer societies? I did. I know what I've mentioned, and in connection to what.

That's very well known. The Tuthmose pharaohs brought it to Egypt. The Romans also copied Carthaginian ships. So what? What's the point? The point is military build up (resting on both professionals and part-time soldiers) seems to be a requirement of agricultural societies. Agriculture brings large-scale war and preparation for war for obvious reasons. Although this is lateral to your reasoning, it's one of your premises. That's why I'm dwelling on it.

No. It is a universal phenomenon: Hittites, Egyptians, the Mitanni, the Hycsos... Quite simply: agriculture implies warfare on a grand scale. Study some ancient history. Bows and arrows I mentioned in connection with hunter-gatherer societies. They sometimes are present in agricultural military societies, sometimes not. Moot point. The Luwians, the Spartans,... it goes on and on. The Spartans are an interesting case: They managed to enslave a whole population to do the agricultural job, while they indulged in their militaristic activity.