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https://www.businessinsider.com/black-hole-how-big-largest-universe-2019-5?utm_source=quora&utm_medium=referral

And in order to distinguish interpretations from each other, they will have to predict different results. Otherwise they will remain as alternative ways of explaining the physics so it makes sense to an audience, rather than the physics itself.

I asked for evidence of your assertion that faith does not inspire suicide bombers. The idea that "not all hate is the result of faith" is so obvious as to not be worthy of discussion. Your dishonest approach to this discussion makes it a waste of my time.

Yes, I am suggesting that an anecdote is not what is considered evidence in any meaningful way. My father smoked for 50 years and never developed lung cancer. Do you also believe that anecdote about him is evidence that smoking does not cause lung cancer?

Nice anecdote. Thank you.

Well religion has had thousands of years of complete control and they never stopped persecuting each other or people who didn't believe the same way they did. I don't think they deserve any more control much less absolute control of life and death over the population.

I'm always reminded of those who live in somewhat dangerous environments, where taking the wrong turn or trusting the wrong currents can be harmful or even fatal, and how those folks learn early to ask those who've gone before for advice on the best ways to survive the challenges. People who don't study science before trying to make sense of science are like the fools who would cross the mountains without first asking where the best paths are. Successful pioneers still need to know a great deal about pioneering before they go exploring.

I noticed that there is some bug in the forum software. Look at this: You see? I just wrote the posting, but my last visited is May, 7th. I noticed this also in other profiles, so it is not an error just when I am looking at my own profile.

+1 I believe the forum uses the same counting app that a certain politician uses to count his votes and discount his opposition's.

No. Never.

It is the size of the event horizon (the radius is directly proportional to the mass). This is slightly larger than the one in M87 that was imaged recently by the Event Horizon Telescope. In both cases, we don't know what happens (happened) in the ultimate condition. We know the early universe was uniformly hot and dense and if you keep extrapolating back you get infinities from the math (a singularity). Similarly, with black holes, when you use GR to predict what happens to the matter, you end up with a singularity. I don't think anyone considers singularities to be physically realistic; they are just an indication that the math no longer makes sense. However, there are two big differences between the universe and a black hole. A subtle one is that the singularity for the early universe is in the past while one for a black hole is in the future (the radial dimension of the black hole becomes time instead of space when you pass the event horizon). A more significant difference is that a black hole is a concentration of mass at one place (our mathematical models of black holes actually describe an unchanging black hole in an otherwise empty universe; but this is a reasonable approximation to reality). The universe on the other hand has always been uniformly (approximately) full of matter.

Here is something useful: Confirmation Bias

Supermassive black holes are quite hard to explain! It isn't known if the black hole came before the galaxy, or was created from material in the galaxy, or they both developed at the same time. There is a limit to how fast black holes can "feed" (because the heat generated by infalling matter blows away some of the material). Current models do not allow black holes to get to that sort of size by absorbing material. It is also hard to see how that much matter could get that closes well. One plausible hypothesis is "direct collapse" where a large cloud of gas collapsed directly to form the black hole, instead of forming stars as it collapsed. But I don't know how well confirmed this is yet. In this model, I think the black hole becomes a seed for the later formation of the galaxy.

Yes, because this 'cog in the machine' is itself neurological activity. But your metaphor is a bit meager. As I said some postings above, it is not a 'one step' emergence, in contrast with the backwards moving congestion in traffic jams. Just to extend the traffic jam example a little. Assume a road has a few old bridges, and because the bridges are old, they are monitored for the weight of the traffic. Now you can imagine what happens when there is much traffic: first there is a maximum weight on the last bridge, then on the one before the last etc. So if all the weight readings are monitored centrally, the operator seems to see something is moving backwards on the road. Now he sends a field engineer to investigate, but being an ex-neurologist, he looks at the cars only, and reports back that nothing is moving backwards. So what we have: a real physical phenomenon (unusual heavy weight moving backwards), that is not visible looking at only individual cars. So physical effects due to emergent phenomena can go together very well. Now imagine that we have not one abstraction level (from individual cars to congestions of cars), but many more (10? 100?) in the brain. Then of course everybody gets lost. So a 'cog in the machine'? Principally, yes, practically endless more subtle. And as soon as we are on the level where we can talk about reasons, decisions, and actions, we can simply define what free will is: decisions according my reasons, actions according my decisions.

I’ve asked twice already. Will try a third time. Do you have an alternative recommendation for terminology that does move you? I’m moved by your challenge regarding the weakness of emergence, just wish you’d take this conversation to the next level and offer a potential replacement.

When dealing with rockets, its the speed of the exhaust relative to the rocket and the total fuel load that determines the final velocity of the rocket, and not how fast the rocket uses its fuel. The later, as pointed out just determines the thrust ( and g forces experienced by the occupants) of the rocket) The two generally run counter to each other. It comes down to the rocket equation: dV = Ve ln(MR) where dV is the final velocity change of the rocket. Ve is the exhaust velocity of the propellant. ln stands for the natural log MR is the mass ratio or fully fueled rocket mass divided by the "dry mass" of the rocket. The rate at which you use up the propellant has no effect on the final velocity, just how long it takes to reach it. Chemical rockets, such as those we use for launches have very good thrust, but fairly low exhaust velocities. Which means they are good at lifting rockets against the pull of gravity, but have practical limits on final velocity. (you can always increase the final velocity of any rocket by adding more fuel, but at diminishing returns. Doubling the fuel mass only increases the final velocity by 58%, and even that is assuming you don't have to add dry mass to the rocket in order to hold that extra fuel or more engine mass to lift the extra weight. Increasing your fuel load by a factor of 10 increases the final velocity by a factor of less than 3 1/2. When it comes to launching a rocket from Earth, you reach limits as how large a rocket you can build.) Even in space, where you don't have to worry about "weight", too high a thrust is not a good thing. The structure of your craft must be able to withstand the g forces that go with that thrust. Higher thrust requires a more robust superstructure, which, in turn increases the dry mass of the ship, reducing the mass ratio and ultimately, the final velocity. You can get higher final velocities by increasing the exhaust velocity, but there is a catch to that also. While doubling the exhaust velocity will double the final velocity, it take 4 times as much energy to double the exhaust velocity. There are limits to how much energy density you can get with chemical fuels, and thus limits to what kind of exhaust velocities you can achieve. Nuclear rockets, like the NERVA design are the next step up and are capable of an exhaust velocity twice that of a chemical rocket, however, a typical NERVA would have a thrust of only 75,000 lbf, compared to a like-sized chemical rocket with a thrust of over 1,000,000 lbf. Ion rockets can achieve much higher exhaust velocities, and thus attain much greater velocities for the same fuel cost, but have very low thrust. The Dawn mission to Ceres was the first deep space probe to make use of this type of propulsion. VASIMR (VAriable Specific Impulse Magneto-hydrodynamic Rocket) which is still under development, falls somewhere between, better thrust than Ion, but better exhaust velocity than chemical. The trick is finding a energy source-engine combination that provides both a high exhaust velocity, but can also generate a significant thrust. One possible candidate is nuclear pulse propulsion. The earliest version of this was project Orion. The basic idea is that you launch nuclear explosives behind you and use the explosions to propel you forward by absorbing the energy with a "pusher" plate. Modern versions would involve detonation of small nuclear fuel "pellets" rather than full-sized nuclear bombs. This type of propulsion is still in the theoretical stages. It really comes down to having a high energy-density fuel source, and being able deliver that energy at a fast rate to generate significant thrust.

I've already been accused of "bitching" about emergence and told that my very presence in this thread inhibits intelligent conversation of AI. (I've seen no evidence of the latter). I respectfully decline to play. I've said several times I don't want to discuss it. I've said my piece and I wouldn't want to inhibit all the insightful and intelligent commentary on AI that I was apparently preventing by my mere presence. Wow. Now you ARE using evolution as a proxy for emergence aka "stuff we don't understand." The bottom line is that when I do respond to my mentions, I get accused of "bitching" and of inhibiting all the world-class commentary on AI that would otherwise ensue if I would just STFU. Then when I DO announce I have nothing else to say on the topic, people complain about that too. Well make up your minds.