Tim88
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Black Hole: Why do we believe that matter could be such dense?
Tim88 replied to MaximT's topic in Astronomy and Cosmology
That's more to the point. Do you mean that simulations that have particles forever more slowly falling towards the centre, using GR equations from our point of view, do not agree with observations? On second thought, likely you just mean that there is overwhelming support for the gravitational collapse of stars, which is getting back to the topic of this thread. 
Black Hole: Why do we believe that matter could be such dense?
Tim88 replied to MaximT's topic in Astronomy and Cosmology
"It never slowed down"??. Correct is to say that of course from its own frame of measurements, it never slows down. From our frame of reference not only those objects become invisible, anything that would be observed by comoving observers is unverifiable  moot as you say. 
Black Hole: Why do we believe that matter could be such dense?
Tim88 replied to MaximT's topic in Astronomy and Cosmology
"From someone like me"? It's a corner stone of doing science.... Just now I got an email from Qreeus telling me that he found a mistake in that analysis. Indeed, that could hardly have been correct, as it seems obvious that in that region anything has to keep moving at locally c. There is indeed no literal surface; instead, as interpreted by a distant observer, there is the huge gravitational potential that slows down infalling objects so much that their radial speed becomes nearly zero. Further, a growing event horizon will of course displace that "surface" to beyond tha 
Black Hole: Why do we believe that matter could be such dense?
Tim88 replied to MaximT's topic in Astronomy and Cosmology
I meant that he reminded me of it. And oops you are right  thanks! OK that works 
Black Hole: Why do we believe that matter could be such dense?
Tim88 replied to MaximT's topic in Astronomy and Cosmology
Indeed. Although, I find "of having coordinate c > 0 at 'EH" is that'" somewhat poorly phrased, I would say "of having c > 0 at the 'EH' position" ; and it's a bit ambiguous that he referred to the pov of the outside observer, according to whom there would indeed be an "infaller's 'stopped coordinatetime clock'" at that position. Anyway, it makes much logical sense, even in relativity there can only be one single reality! He could be more polite though (not that he's the only one here...). Note: yesterday Qreuss mentioned this forum to me and just now I tried to search his 
No, not those; that's not what is meant with "the predecessors". The comparison is with the simplified calculations for time periods of 100'000 yrs and more, the socalled Milankovitch calculations and variants thereof  http://www.indiana.edu/~geol105/images/gaia_chapter_4/milankovitch.htm .

Apparently the approximate calculations that everyone used until now do not even include the nutation; in other words, those do not "lag" the measurements but simply don't reproduce them  and apparently they were wrong for their intended use as well. The correct and accurately calculated nutation is one of the verifications of the correctness of the new, exact calculations that are discussed in the paper. Regretfully, we cannot directly verify the calculations over 100'000s of years with measurements.

I now got a reply from Smulsky. He points out that in fact there is an additional, astronomical verification: the constant of nutation. That's an oscillation of 9.2'' with a period of 18.6 years  https://en.wikipedia.org/wiki/Astronomical_nutation#Nutation_of_the_Earth.27s_axis As described in Smulsky's fig.10, this observed phenomenon is exactly reproduced by his calculation model  Smulsky J.J. Fundamental Principles and Results of a New Astronomic Theory of Climate Change. He further comments in his email (with a slight correction of his Google Translate Russian>Engli

Could relativity be incorrect
Tim88 replied to PrimalMinister's topic in Modern and Theoretical Physics
Probably you misunderstood him. He was comparing constant straight line acceleration with constant centripetal acceleration (= in a circle, or "rotational"): In contrast to rectilinear acceleration, there is no energy input.for the simple case of a body that is freely rotating at constant centripetal acceleration (constant rotation speed). 
Could relativity be incorrect
Tim88 replied to PrimalMinister's topic in Modern and Theoretical Physics
mistermack didn't say "rigid body"... anyway, that's an interesting assertion; please clarify! 
Any Anomalies in Bell's Inequality Data?
Tim88 replied to TakenItSeriously's topic in Quantum Theory
I now found it back: https://arxiv.org/abs/1112.2629 In a nutshell, the authors conclude that the experimental data by Weihs et al are not in agreement with the predictions of QM: "It is highly unlikely that quantum theory describes the data of the EPRB experiment that we have analyzed." As it's apparently only in ARXIV, it's definitely a discussion item  up to TakenItSeriously if he's interested! 
As I now understand it, the approximate and the accurate calculations are all accurate (agreeing with each other and with measurements) for the time of human history. Consequently, it is necessary to compare the calculated variations with the geological record. In the paper a comparison is made with the ice ages, as established with dating techniques.

Could relativity be incorrect
Tim88 replied to PrimalMinister's topic in Modern and Theoretical Physics
Indeed accelerating frames are for local use; that was already done in classical mechanics but GR extended it for all physical phenomena. There's another issue that none of us addressed but is coming back every time: there is no "moving faster than light eventually" involved. Accelerating objects as measured with a "stationary frame" (also called "coordinate acceleration") accelerate less and less fast as they reach high speed. That was even one of the first predictions of SR, about the fact that electrons cannot be accelerated to the speed of light. Note also the subtle difference w 
Any Anomalies in Bell's Inequality Data?
Tim88 replied to TakenItSeriously's topic in Quantum Theory
Hi Mordred, thanks for the wealth of references. I doubt that Bayesian vs Gaussian statistics matters here, as I cited how Bell did not even pretend to give a rigorous proof of his starting equation. Nevertheless, since I have the statistics book of Jaynes [PS I'm well beyond chapter one lol] and still plan to work my way completely through it one day, your references are appreciated and maybe one day I'll contact you with questions about a certain chapter. Also, I agree that the "particle" approach is probably a dead end  just for the record, as we're drifting away from the topic ( 
Any Anomalies in Bell's Inequality Data?
Tim88 replied to TakenItSeriously's topic in Quantum Theory
That's a good one! In fact there seems to be something of a mathematical "anomaly" here. That equation is according to Jaynes an unproven simplification of locality in Bell experiments. According to him, "fundamentally correct" would be (in his notation): P(ABabλ) = P(ABabλ) P(Babλ) Now, I'm not 100% sure that he was right, but I suppose that an expert like him would not make a mistake about such a fundamental issue. And as a matter of fact, even Bell admitted that his simple equation is not based on mathematical rigor but instead, it is based on plausible looking assumptions ("It