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If only black holes weren't illogical! [1] Any decent software developer (i.e. highly logical thinker) who knows basic info about black holes can look at the pi

If only black holes weren't illogical! [1] Any decent software developer (i.e. highly logical thinker) who knows basic info about black holes can look at the picture there to quickly see that black holes are inconsistent with the core postulate of general relativity, the equivalence principle. They're a bug! (which Einstein spent a decade trying to find, or some other way that nature could prevent black holes he thought didn't "smell right", and no that's not my blog) [2] is previous discussion showing no bona fide flaw in the argument. I've not seen anyone refute that simple picture, which should be easy if it's incorrect. That black holes are a bug doesn't mean we can't explain observations. Gravitational redshift still exists to explain massive objects emitting no discernible light (might be only one photon every year, away from Earth). [1] http://finbot.wordpress.com/2008/03/05/no-black-holes/ http://finbot.wordpress.com/2008/03/05/no-black-holes/ [2] https://news.ycombinator.com/item?id=4926603 https://news.ycombinator.com/item?id=4926603

pdonis 13y ago
Here's another relevant discussion on HN that you conveniently forgot to link to, which does explain in detail the flaw in your argument (the discussion you did link to does too, but not in detail): https://news.ycombinator.com/item?id=5233894 https://news.ycombinator.com/item?id=5233894 Click on "parent" to see the post of yours that I was responding to.
- fargolime 13y ago
  You've linked to that before, but there's nothing there that refutes the blog (not my argument). If there's a flaw it should be a sentence or two of logic, not multiple paragraphs that summarize as "it's not that simple". The blog shows that inertial frames falling through a horizon are that simple (after all, the equivalence principle demands that), and Taylor and Wheeler agree there. Extraordinary evidence is not a requirement per the scientific method. "Extraordinary" is not a scientific concept.
  - pdonis 13y ago
    there's nothing there that refutes the blog I understand that you don't agree that what I posted refutes the blog, but I'm not trying to convince you, and I'm not going to rehash the argument here. I'm just linking to that discussion for the record, so others reading this thread will understand that your claims and the blog's claims about black holes are not undisputed. (not my argument). You may not have written the blog post, but you are claiming it's correct, so it is "your" argument in the only sense that matters here. If you're not willing to own the argument when it's challenged, then you shouldn't be linking to it. If there's a flaw it should be a sentence or two of logic, not multiple paragraphs that summarize as "it's not that simple" That's not the summary of what I said. The summary of what I said is this: the blog post's claims about what the theory of relativity actually says are not correct. So the blog post is not refuting the actual theory of relativity; it's refuting a straw man version of the theory that the blog post's author has constructed in his own head. Taylor and Wheeler agree there Agree with what? That there can be an inertial frame that falls through the horizon? Yes, of course. But that does not mean Taylor and Wheeler agree with the blog post's claims about black holes. The fact that there can be an inertial frame that falls through the horizon does not mean the blog post's claims about the details of how such frames work are correct. I went into detail about what's wrong with them in the thread I linked to.
    - fargolime 13y ago
      What sentence in that picture's caption is wrong, or what doesn't follow from its premises? Asking for extraordinary evidence isn't a scientific thing. Valid logic is all the evidence needed. Yes it's my argument in that way. I'll challenge a refutation or accept it, but that's difficult when the counter argument is a vague wall of text. If I were to try to summarize what you think is wrong I couldn't do it. I can't decipher your points to see how they attempt to refute any particular sentence in the blog. Please be way more clear and short and to the point, and I'll agree, or disagree with my reasoning. (For example check out Millstone's reasoning above. He/she disagrees that an inertial frame can cross the horizon. One short sentence is enough to summarize!) > the blog post's claims about what the theory of relativity actually says are not correct Anyone can say that; be more specific. What the blog says in that way sources from experts in relativity. Its statement of the equivalence principle, for example, is Kip Thorne's. > Agree with what? They agree that frame X in the blog post is validly defined and validly used in the thought experiment. Their quote in the blog makes that clear.
millstone 13y ago
The simplest way to show the essential physical error is via this picture, from the article: http://finbot.files.wordpress.com/2008/03/t9.png http://finbot.files.wordpress.com/2008/03/t9.png This picture shows the event horizon as having constant position in a free-falling frame. But the event horizon accelerates in all nearby inertial frames, exactly like how the surface of the earth accelerates (towards you) in every inertial frame near the earth. So the line representing the event horizon cannot be straight: it must curve. It must be hyperbolic. That is the key feature that the article gets wrong. > Then law J shows that a locally inertial frame relative to which the particle is at rest can’t even in principle extend below the horizon The horizon forms a hyperbola in any such inertial frame. Because the horizon accelerates, whether a spatial point is below the horizon depends on time. If you have a test particle moving with constant acceleration, can you reach it with a signal at some point after it leaves? In Newtonian physics you can: just send the signal fast enough. But in relativity, test particles moving with constant acceleration can be "uncatchable" even though they never reach c. See Rindler coordinates for more. This illustrates why an outgoing test particle cannot cross the event horizon. Picture the event horizon as a hyperbola, and the test particle as an asymptote: it can never intersect it. > a test of the laws of physics can distinguish X from an inertial frame in an idealized, gravity-free universe Well duh. There are no inertial frames that cross the horizon. Technically any two separated points in our frame will be accelerating with respect to each other. We approximate this acceleration as zero, but this approximation can break down near the speed of light, as things tend to do.
- fargolime 13y ago
  > This picture shows the event horizon as having constant position in a free-falling frame. But the event horizon accelerates in all nearby inertial frames The line represents the horizon at a single moment in the life of frame X, during which it has a specific position relative to X and is not accelerating relative to X. > If you have a test particle moving with constant acceleration, ... The test particles are defined as freely falling. The frame X is defined as inertial. No free particle can accelerate in an inertial frame (at least not measurably), including in relativity. Check out Taylor and Wheeler's quote at the bottom of the blog post: "Keys, coins, and coffee cups continue to move in straight lines with constant speed in such a local free-float frame." According to you, those things would not move at constant speed; rather they'd be "moving with constant acceleration". > Well duh. There are no inertial frames that cross the horizon. This again disagrees with Taylor and Wheeler's quote. They are clear that not only can an inertial frame cross a horizon, but also that frame is "a free-float frame like any other". I didn't respond to everything you said because it hinges on the same disagreement. Before we could get further in the discussion you would need to accept Taylor and Wheeler there, or show how I'm misunderstanding the conflict between what you said and their quote that seems to explicitly disagree with you.

pdonis 13y ago

Here's another relevant discussion on HN that you conveniently forgot to link to, which does explain in detail the flaw in your argument (the discussion you did link to does too, but not in detail): https://news.ycombinator.com/item?id=5233894 https://news.ycombinator.com/item?id=5233894 Click on "parent" to see the post of yours that I was responding to.

fargolime 13y ago
You've linked to that before, but there's nothing there that refutes the blog (not my argument). If there's a flaw it should be a sentence or two of logic, not multiple paragraphs that summarize as "it's not that simple". The blog shows that inertial frames falling through a horizon are that simple (after all, the equivalence principle demands that), and Taylor and Wheeler agree there. Extraordinary evidence is not a requirement per the scientific method. "Extraordinary" is not a scientific concept.
- pdonis 13y ago
  there's nothing there that refutes the blog I understand that you don't agree that what I posted refutes the blog, but I'm not trying to convince you, and I'm not going to rehash the argument here. I'm just linking to that discussion for the record, so others reading this thread will understand that your claims and the blog's claims about black holes are not undisputed. (not my argument). You may not have written the blog post, but you are claiming it's correct, so it is "your" argument in the only sense that matters here. If you're not willing to own the argument when it's challenged, then you shouldn't be linking to it. If there's a flaw it should be a sentence or two of logic, not multiple paragraphs that summarize as "it's not that simple" That's not the summary of what I said. The summary of what I said is this: the blog post's claims about what the theory of relativity actually says are not correct. So the blog post is not refuting the actual theory of relativity; it's refuting a straw man version of the theory that the blog post's author has constructed in his own head. Taylor and Wheeler agree there Agree with what? That there can be an inertial frame that falls through the horizon? Yes, of course. But that does not mean Taylor and Wheeler agree with the blog post's claims about black holes. The fact that there can be an inertial frame that falls through the horizon does not mean the blog post's claims about the details of how such frames work are correct. I went into detail about what's wrong with them in the thread I linked to.
  - fargolime 13y ago
    What sentence in that picture's caption is wrong, or what doesn't follow from its premises? Asking for extraordinary evidence isn't a scientific thing. Valid logic is all the evidence needed. Yes it's my argument in that way. I'll challenge a refutation or accept it, but that's difficult when the counter argument is a vague wall of text. If I were to try to summarize what you think is wrong I couldn't do it. I can't decipher your points to see how they attempt to refute any particular sentence in the blog. Please be way more clear and short and to the point, and I'll agree, or disagree with my reasoning. (For example check out Millstone's reasoning above. He/she disagrees that an inertial frame can cross the horizon. One short sentence is enough to summarize!) > the blog post's claims about what the theory of relativity actually says are not correct Anyone can say that; be more specific. What the blog says in that way sources from experts in relativity. Its statement of the equivalence principle, for example, is Kip Thorne's. > Agree with what? They agree that frame X in the blog post is validly defined and validly used in the thought experiment. Their quote in the blog makes that clear.

millstone 13y ago

The simplest way to show the essential physical error is via this picture, from the article: http://finbot.files.wordpress.com/2008/03/t9.png http://finbot.files.wordpress.com/2008/03/t9.png This picture shows the event horizon as having constant position in a free-falling frame. But the event horizon accelerates in all nearby inertial frames, exactly like how the surface of the earth accelerates (towards you) in every inertial frame near the earth. So the line representing the event horizon cannot be straight: it must curve. It must be hyperbolic. That is the key feature that the article gets wrong. > Then law J shows that a locally inertial frame relative to which the particle is at rest can’t even in principle extend below the horizon The horizon forms a hyperbola in any such inertial frame. Because the horizon accelerates, whether a spatial point is below the horizon depends on time. If you have a test particle moving with constant acceleration, can you reach it with a signal at some point after it leaves? In Newtonian physics you can: just send the signal fast enough. But in relativity, test particles moving with constant acceleration can be "uncatchable" even though they never reach c. See Rindler coordinates for more. This illustrates why an outgoing test particle cannot cross the event horizon. Picture the event horizon as a hyperbola, and the test particle as an asymptote: it can never intersect it. > a test of the laws of physics can distinguish X from an inertial frame in an idealized, gravity-free universe Well duh. There are no inertial frames that cross the horizon. Technically any two separated points in our frame will be accelerating with respect to each other. We approximate this acceleration as zero, but this approximation can break down near the speed of light, as things tend to do.

fargolime 13y ago
> This picture shows the event horizon as having constant position in a free-falling frame. But the event horizon accelerates in all nearby inertial frames The line represents the horizon at a single moment in the life of frame X, during which it has a specific position relative to X and is not accelerating relative to X. > If you have a test particle moving with constant acceleration, ... The test particles are defined as freely falling. The frame X is defined as inertial. No free particle can accelerate in an inertial frame (at least not measurably), including in relativity. Check out Taylor and Wheeler's quote at the bottom of the blog post: "Keys, coins, and coffee cups continue to move in straight lines with constant speed in such a local free-float frame." According to you, those things would not move at constant speed; rather they'd be "moving with constant acceleration". > Well duh. There are no inertial frames that cross the horizon. This again disagrees with Taylor and Wheeler's quote. They are clear that not only can an inertial frame cross a horizon, but also that frame is "a free-float frame like any other". I didn't respond to everything you said because it hinges on the same disagreement. Before we could get further in the discussion you would need to accept Taylor and Wheeler there, or show how I'm misunderstanding the conflict between what you said and their quote that seems to explicitly disagree with you.