baric

This is untrue.

Keep in mind that all black holes are spinning and doing so at an extremely high rate. There's no other way to conserve angular momentum. It's just all happening within the event horizon.

This is exactly correct.

Here's a thought experiment.. (yes, I know this is implausible, but please accept the premise) Premise: Astronomers discover a huge, Pluto-sized body deep in the Kuiper Belt and realize that, due to a recently perturbed orbit, that it will directly impact Earth in 30,000 years -- destroying all life on our planet. Because of its size, this impact is unavoidable. Many suggest that the only way for humans to survive extinction is to start an intensive and expensive effort to terraform and colonize Mars, which would take at least 20,000 years to complete. Question: Does our generation choose to do anything about it, or do we shrug and decide to let future generations worry about it?

We all understand the timescales involved, but the reality is galactic colonization (or even noticeable super-advanced civilizations in a single star system) are contingent upon futuristic technologies that remain undiscovered. To suggest colonization for example, requires either the possibility of relativistic speeds or the ability for organisms to survive eons in deep space (in transit). There are significant technological hurdles to both of those options and clearing those hurdles may simply not be possible for biological civilizations constrained to the resources a single planet. Even terraforming nearby Mars is projected to take THOUSANDS (>10K) of years. While that may seem like a blip in galactic time, that planet is a very close analogue for our own (lucky us!) and yet the timescale is still much longer than our written history. It's just as possible that interstellar travel is so impractical that it makes far more sense for civilizations to simply terraform their local system to suit their needs.

Your bias towards your own species clouds your judgment. The most populous and durable organisms on this planet consist of just a single cell. And are you really suggesting that we are more well-adapted than this species? http://news.bbc.co.uk/earth/hi/earth_news/newsid_8127000/8127519.stm

I wish I could +1 your post separately for each of those excerpted comments.

So you are drawing conclusions governing evolution on the grand scale of eons from population trends in the last ten thousand years? Also, your "rule" is incorrect. Better adapted organisms replace less adapted organisms. Conditions could change on this planet (and have in the past), that could make single-celled organisms the most well-adapted forms on the planet. Are you aware that some scientists believe that the "more advanced" humans almost became extinct just 70,000 years ago when our population crashed to possibly under 10,000 due to catastrophic environmental changes? http://en.wikipedia....astrophe_theory

Perhaps we are simply quibbling over a semantic definition of "smart". I am not talking about some innate, inborn characteristic. I am talking about environmental characteristics like rationality (learned), academics (learned), and passion for their field of study. These things combined make scientists, as a group, the undisputed experts in their fields of knowledge. They are SMARTER than those whose desires and efforts took them into other fields. Of course not. "Scientist" is a profession. Being a skeptic is certainly a valuable, perhaps indispensable, prerequisite for being a good scientist. But that alone does not make you one. Ridiculing those less able is symptom of insecurity, an unfortunate characteristic of human personality. It occurs in ALL professions, and human scientists are no more immune to that personality flaw than anyone else. You need to recognize it as a flaw of the ridiculer, not you, and shrug it off. All that ultimately matters in science is the pursuit of knowledge.

I hate to burst your bubble, but scientists as a whole ARE far smarter than the average person. There is a huge academic threshold that has to be crossed and then they spend their entire lives in the pursuit of knowledge in their particular fields. So yes, in their fields, they are much SMARTER than you or I. It's a fact. If they weren't, they could not cut it as scientists. Just like soldiers are braver. Models are prettier. Professional athletes are more fit. etc etc

Still an incoherent, undefined term. If you admit that you don't know what "god" is (an "unknown force"), then how can you rationally posit it as an explanation for anything?

Until you can provide a coherent definition of the word "God", then you can say the same thing by positing that the universe is the product of blarg. (Blarg is another incoherent, undefinable word I just made up.) No one can really define what "god" means, so using that word renders a statement ultimately meaningless.

By "ridiculous" assertions, I mean an those so detached from established science that there are only two plausible explanations for their existence: 1) There is a known, non-scientific agenda being pushed that requires ignoring clearly established observations. Examples include creationism/ID (religious agenda), global warming denial (economic/political agenda), crop circles, ancient astronauts and telepathy (huckster agenda). or 2) There is pattern of willful ignorance by a particular presenter who rehashes the same, tired theories without acknowledging previous refutations. In both cases, ridicule is warranted rather than repeating the same, meticulous refutation that has been made many times before. Unnecessarily wasting time on frauds like these diverts attention from more productive activities! This does not mean we should ridicule someone who is innocently presenting a flawed case. However, if they are really uninformed there is no shame in plainly letting them know that they need to learn a bit more before, for example, attempting to disprove relativity.

The first thing is to think of an example of ridicule. That was the first to come to mind. However, Hoyle's labeling of "Big Bang" had the opposite effect intended because it gave a memorable name to the new theory. My example about cold fusion is more concrete. Except that there is no ID theory to prove. Seriously. It's little more than an untestable "God did it" statement that falls apart upon cursory examination.

Fred Hoyle's rejection of a competing theory that he dismissed as the "Big Bang" theory. Also, the rapid rejection and ridicule of "cold fusion" in the late 80s undoubtedly redirected a lot of research time back away from it and onto more worthy subjects.

I'm going to ignore the physical impossibilities of this and try to answer your question per the intent you asked. The Sun burns about 635e12 kg per second of Hydrogen for fuel. Jupiter has a mass of 1.89e27 kilograms, 90% of which is Hydrogen (fuel for stellar fusion). This means that, in order to burn as brightly as the Sun, Jupiter would burn 2.68e12 seconds before running out of Hydrogen fuel, or about 85,000 years. With two suns, one at 1 AU from Earth and the other averaging 5.2 AU from Earth, our planet would receive energy equivalent to the Sun being 4% closer. That would raise the effective temperature of our planet about 5 degrees Kelvin, or as bad as some of the worst-case global warming scenarios -- on top of our own global warming issues. The ice caps would melt, lowering the albedo of the planet and probably warming things up a bit more. It would be global warming on steroids, with all of the flooding, agricultural and sociological problems that would cause. For 85,000 years.

There were indeed more than one tool-using species of hominid living concurrently. Our particular species won the war of competition long before the first pages of history were written. If another hominid species had won out, they might very well indeed be here, in some alternate timeline, posing the same questions. Are you suggesting that humans made that same step in less than 4300 years? I'm not exactly sure you understand how glacial technological development was for our species until the very recent past. Probably never? In the tremendously long chain of evolutionary adaptations that have led to our tool use and technology, chimps have undoubtedly traveled over 99% of the way with us. To assume that they could not take that last step if we suddenly disappeared seems very presumptuous.

When two scientists disagree, the odds are great that one of them is going to walk away from the discussion slightly wiser. Normally, politeness need not enter into the equation. If it does, it should scale with the absurdity of the assertion. Examples: Assertion #1: "consistencies in ancient Greek texts indicate that an historical Atlantis is a real possibility" Reply #1: "I've never seen literary evidence to warrant that level of certainty. I'd like to hear your case for it" Assertion #2: "an iron-age Atlantis existed during the Mycenaean period at Santorini, and their survivors may have triggered the rapid advances in classical Greece" Reply #2: "wow, that's pretty far out there. Your timelines are way off and there is no archaeological evidence to support that. Perhaps you should study up more on this subject" Assertion #3: "a historical Atlantis existed with futuristic technology and their descendants now visit us in spaceships" Reply #3: "that is complete rubbish and you are a nut"

An adaptation that allows generic tool use is a TREMENDOUS selection advantage because it removes the need for further morphological changes to adapt to new environments. Once this threshold is crossed, a species is rapidly able to move into many previously unsuitable habitats, effectively stunting the evolutionary progress of all other species. It is ubiquitous. In fact, you will find tool-using animals in almost every corner of the Earth, driving out all other competitors for natural resources. Of course, these animals are all members of the same species. The competition for resources will prevent multiple tool-using species from co-existing for any amount of time. I was using the term 'brain' as a shorthand for intelligence, but obviously not every bundle of nerves fits that description. Nevertheless, some early invertebrates did indeed eventually evolve intelligent brains. I missed it. I'll go look at it. Anatomic limitations are only a temporary constraint. If tool use provides a selective advantage, those individuals more anatomically suited to use the tools efficiently will disproportionately contribute to the gene pool of future generations.

The problem is that "ridicule" is a subjective term. If someone proposes "theory A", someone else may point out that theory leads to logical conclusions that are clearly absurd. The first person may consider that "ridicule", but the second may consider it an illustrative refutation. For example, Albert Einstein used the term "spooky action at a distance" to ridicule the QM notion of non-locality. My opinion is that, as long as people are not PERSONALLY ridiculed, then it is all legitimate discussion.

That's interesting, because I read your post in its entirety, restated your premise using your same choice of words, and then gave an indication of why I considered it fallacious. This is also interesting. You accuse me of not reading your post and then reinterpret your words post-hoc. Despite your use of quote marks above, you in fact did not quote Sagan at all and, regardless of that, at no point did I claim that the lack of evidence represents a falsification. What you said was (in giant bold), and what I responded to, was: "I can't see" does not imply that there is nothing to see" If you can't see it, then you have no evidence to support it. Until such evidence is found, it is conjecture. In fact, dismissing "I can't see" as a justification for believing those interstellar structures may exist is just another form of Russell's Teapot fallacy -- thus my teapot reference. The Kardashev scale, in the first paragraph of the wiki link you provided, is described as "only theoretical" and such civilizations are "highly speculative". And since advanced alien structures are so speculative, no one really has any idea of how they could be detected or even if any anomalous detections are ever indications of such a civilization. This is why they are science fiction. So while it may make an interesting addition to a Star Trek script, it really has little place in discussions about actual science.

Yes, hypothetical Super-Aliens could certainly live in planet-sized space habitats, orbiting around white dwarfs and harvesting planets for raw materials, making it impossible for us to observe and disprove their existence. Are these "cybertron" habitats shaped like teapots, by any chance?

You did not provide any evidence of actual "crunched numbers". In fact, the Kardashev scale link was exhibit #1 that you are residing in credulous science fiction land. I mean, your "Beam Power Propulsion" page actually compared launching an object weighing 1.8 ounces for 12 seconds to Goddard's first rocket test flights and then extrapolated that peashooter launch to placing a 1 kg probe into orbit for $20 worth of electricity! That is a prime example of irrational exuberance. Here's are some example pages that is a bit more grounded in reality: http://en.wikipedia.org/wiki/Ion_thruster http://en.wikipedia.org/wiki/Variable_specific_impulse_magnetoplasma_rocket Now, what do you see on those pages that is missing from your references? Crunched numbers. This does not mean that laser-powered launches will never happen, but it is far too early to look at them and predict planetary colonization.

Unfocused and at broad wavelengths! A solar collector can only be in one place at a time, so you have to measure the lumens per area. It's one thing to build a cost-effective solar collector on Earth to gather photons within a narrow spectrum, and entirely something else to build, launch and maintain millions of orbital collectors and efficiently transfer their energy (via laser, presumably) to some local users. That is engineering on an unspeakably grander scale that we have ever attempted. You're saying that, RIGHT NOW, we have the technology to: I dispute that. Science fiction is really interesting, I understand that, but you use "would" far too extravagantly. You should be wary of speaking with certitude about futuristic and uncertain technologies. Science does not prove negatives. It never has, and never will. Two possibilities: They are stuck on their planets, waiting for us to notice them? They are dead? The paradox is easily solved without invoking human exceptionalism or hiding aliens.

I agree, which is why I said there would need to be a "huge technological jump to find new sources of energy" in order to continue advancement beyond the limits of Earth. So the questions become, by precedence: 1) Is this jump even possible? (i.e. does the nature of the universe allow for it) 2) Is this jump practical? (i.e. is attaining this level within the scope of a planet-based civilization?) 3) Will this jump occur? (i.e. is human civilization capable of making this jump before killing themselves or running out of time?)