Strange

While there may be some sort of unknown "dark force" interaction between dark matter, it cannot be equivalent to or as strong as the interactions between normal matter. If it were, then dark matter would intereact like normal matter does an collapse to form objects equivalent to planets and so on. The fact it exists in diffuse clouds supports the idea that it only interacts gravitationally. Neutrinos don't interact with anything much, either. (But they don't have enough mass to be dark matter).

To explain what happens in extreme conditions such as black holes, the early universe and probably also things like supernovae and neutron stars. Apart from that, there is no real "need" but it is what scientists do: try and learn more...

Are you leaving the cassette in the machine? If so, it could be that your heads have got magnetised and are partially erasing the section that is near them. Solutions: don't leave the tapes in the machine! Buy a demagnetiser(if such things are still available in this digital age).

That's science!

Einstein added the constant because it was assumed at the time that the universe was static, while GR predicted it should expand or contract. When it was confirmed that it was expanding, then it was taken out again (or rather, set to 0). When it was then found that the expansion was accelerating, it was reintroduced (with a value set by the observed rate of acceleration).

Mercury is very, very toxic. http://en.wikipedia.org/wiki/Karen_Wetterhahn She is putting her, and her patient's, health at serious risk. In many countries, treatments like this are illegal for very good reasons. (I am guessing these are skin lightening creams?)

Definitely not. Although I suppose it is possible that those land masses were once position over the North Pole (because they moved, not the Earth's axis). I don't believe any of those things happened. Do you have a reference?

In that example, you could take into account the distance that each measurement was made (and therefore how long ago), the half life and the formation mechanism and then extrapolate to calculate the average amount present. I wouldn't be surprised if there are elements where exactly that is done as many isotopes have half lives that are very short relative to the lifetime of stars, or even very short compared to the frequency of their production methods. This seems to be yet another ill-defined "problem" you have invented that is simply based on a poor understanding of the methods and mathematics used.

That's great from someone who keeps referring to "schwartsman". It just means infinite density. Full stop. As in: the density is infinite. Which neither you nor the author of that thesis seem to have. (But he has the excuse of writing in a foreign language. And I bet he knows how to spell Schwarzschild.)

OK, Jonah, that's enough.

That is just an example of the poor wording you find on Wikipedia occasionally. Even on the pages that are accurate. All it means is that if the mass is within a radius less than (or equal to) the Schwarzschild radius then it will become a black hole. There could be two ways of defining the size of black hole: the event horizon (Schwarzschild radius) or zero (which is the radius of the mass inside the black hole). I know you think that making stuff up is better than using well established and tested science, but I tend not to agree. Of course. You have been given any number of references to books, websites and other sources of information. (But then you complain because we are not just making it up. Can't win with some people.)

So you would actually be safer falling into a very large black hole as the tidal forces would be less and so you wouldn't be torn apart (well, not immediately). You wouldn't notice anything at all as you pass through the event horizon. And finally, if you try and use your rockets to slow your approch to the center, you will actually get there faster. Apparently. So your imagination isn't always helpful.

The radius of a (non-rotating) black hole is the Schwarzschild radius. It doesn't create energy. Yes, because there is no such thing. You may be thinking of momentum. Or force. Or acceleration. Or.... who knows.

And they had to give that belief up when they found that even things as simple as the diagonal of a square or the circumference of a unit circle are irrational. Apparently not.

I don't believe that is a principal (profound or otherwise). That is pretty much the definition of natural numbers. Hence the name. Are they? The derivations I have seen start from zero. That is not true. There is no simple integer relationship between the energy levels of an electron in an atom, for example. And electromagnetic radiation is quantized but can have any energy/frequency. Quantum theory explains that.

I have seen arguments that, for example, Chihuahuas and Great Danes should be considered separate species because they are reproductively isolated. It is probably mainly a matter of convenience that they are still considered one species. In a variety of ways: http://www.talkorigins.org/faqs/faq-speciation.html (That page also has a good discussion of the difficulties of defining species.)

As far as I know, dark energy does not exert any force on objects. And, as it is thought to be present throughout all space, the distance question is irrelevant.

This one? Rqc2p and 60S ribosomal subunits mediate mRNA-independent elongation of nascent chains http://www.sciencemag.org/content/347/6217/75.abstract I don't have access to the full paper, but the abstract doesn't appear to support that claim. Could you explain why you think it does. Note that the central dogma of molecular biology is simply a statement of how DNA transcription works. (And, like all science, if evidence showed it to be wrong, then it would be changed.) That is true of all science. That is how science works. As chemical reactions are not arbitrary and life require stability and structure, not chaos, this is a totally unjustified extrapolation.

I don't think that is quite true. However, the forces are quantized, which means they are mediated or represented by (virtual) particles. But the electromagnetic force (as the simplest example) falls of with the square of distance in the same way that gravity does. They will both get smaller and smaller with distance but they will never reach a minimum value and never stop (although they may become insignificant compared to other forces after some time (e.g. we can ignore the gravity of Jupiter when calculating the orbit of the moon). The difference with gravity is, as you say, that it is an effect of the geometry of space-time so it isn't really considered a force. (Although it can still be treated as a force, because using Newton's laws is much simpler than GR and usually good enough). The reason that people want to quantize gravity is to unify it with quantum mechanics. There are conditions (such as black holes or the early universe) where we can't really explain / describe what happens because we don't have a theory of quantum gravity. Changes in gravity propagate at the speed of light. Often you can, yes. It depends what you are trying to calculate and how accurately.

Which again reinforces the idea that one can't rely on intuition when thinking about these things! I would be interested to know how your imagination answers the following questions (this is not an attempt to trick you, I'm just curious what your intuition tells you). Imagine you are in a spaceship (like one of those one-man submarines) exploring black holes. You decide to go into one by letting your craft just fall towards it. 1. Is it better to do this with a supermassive black hole (with the mass of millions of stars) or a smaller one (about 10 stellar masses)? (And why?) 2. What will you experience as you fall past the event horizon? (And why?) 3. Will it take longer to fall to the center if you carry on in free-fall, or if you use you engines to try and orbit? (And why?)

That is pretty much it. Did you read the John Baez article that Mordred referenced. It explained that (but in quantitative terms, so it is useful, rather than just a vague concept which is not useful). The only bit I would question is "not particles". You will note that the Baez article uses particles to describe what will happen in particular cases. The idea of a "test particle" is an important concept. Admittedly, this is not the same as a "particle" in QM, which may be what you are thinking of. The behaviour of supernovae and the creation of black holes is, as far as I know pretty well understood and modelled. (It is not something I know much about as it is very complex.) No doubt there are some open questions (this is science, after all). But it is certainly not speculation. No. They both describe exactly the same thing. SR is just a subset that only consider inertial motion. GR is the full version that includes gravity. Definitely not. GR is an extension of SR. GR can be simplified to SR in the absence of gravity (this is effectively the definition of "local" in GR). Neither of these will make it spin. It is very likely that all black holes spin because the stars they formed from were spinning. I suppose there might be a star somewhere that is not spinning - that would create a black hole with no spin. Or two black holes with exactly opposite spin could merge. It is just very unlikely for a black hole to have no spin. And this is why you get some negative reactions. "schwarztrman" ? "it takes energy to spin something though" - it might take energy to start something spinning. But we are talking about something which is already spinning (or, strictly speaking, in the case of a black hole has angular momentum). No energy is required to keep it spinning. "vectors from some of the energies" - energy is not a vector "vectors have to work to create spin" - see above. Gravity. The Schwarzschild radius is the radius of the event horizon (for a non-rotating) black hole. For a rotating black hole, the event horizon is smaller, as has been shown. The problem is, your descriptions are vague and based on the misuse of well-defined terms. What you think is a failure to "keep up" or "see" is people attempting to give you better explanations (i.e. ones based on what science actually knows) and to correct nonsense like "energy vectors". Sometimes giving a better explanation can only be done by reference to the maths. Sometimes the maths is provided to demonstrate that it is not just someone's opinion or belief. You may have figured out the inverse square relationship based on the areas of spheres (well done) and had a lucky guess (*) about the radius of spinning black holes but that does not mean that your imagination will always get you the right answers. (*) And it was a guess because your attempt to justify it is just unmitigated nonsense.

elfmotat has presented factual information and has attempted explanations at a level suitable for you (which is pretty tough). You are now behaving like a total dick. I don't know why. There is nothing at all that you can teach elfmotat or 90% of the members of the forum. That is not "pride", it is just a judgement based on the level of knowledge you have displayed. You suspected it but you repeatedly denied it. Got it. You might think that. But attempting to extract some sliver of meaning from your incoherent rambling full of misused jargon is hard work. A number of people have made the effort, in order to try and help you learn but you simply turn on them with arrogance and insults.

Thanks for the correction and detail.

I believe the radius of the event horizon for a Kerr black hole is the same as for a non-rotating one (but the black hole is no longer simply defined by the event horizon). Not really. The pressure will contribute a small amount to the gravity. But this is normally insignificant. (It can become significant for neutrons stars.)

Oh good grief. You have made it obvious that you don't know much (*) about evolution, but do you really think "survival of the fittest" means that the fastest and strongest survive? I mean .... good grief. (*) "Nothing" might be more accurate, but I'll give you the benefit of the doubt. Of course you can. And of course it can. It is a science so by definition it is quantitative. Some parts of evolutionary theory are highly mathematical.