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Eldar Black Holes

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Re: Eldar Black Holes

#81

Post by IntronExon »

olegkikin wrote: post #77
IntronExon wrote: post #67

Earlier quoted context omitted.

At this point a few issues arise. The first is that what you’re describing is a feature of the Schwarzschild metric, which applies to a model black hole, which is time-independent and eternal. There is no particular reason to believe that this accurately describes black holes in nature. For example this metric can not describe the merger of two black holes, but we now have observational evidence that this does indeed…

> The crew of a 99.9% lightspeed ship doesn’t experience time dilation until they return home. That's not true. They see the universe around them moving much faster. Time dilation has nothing to do with "returning home".

Seeing the universe around them is comparing clocks with another frame of reference. On the ship, life at 99.9% and life at 1% of c is identical. By the same token, if you fell into an (inactive) supermassive black hole, your watch would trick the same way into and past the event horizon. You would in fact live inside the hole for hours until you were torn asunder.

Re: Eldar Black Holes

#82

Post by whatshisface »

fao_ wrote: post #25
wcarss wrote: post #18

Earlier quoted context omitted.

off-topic a bit: does anyone have suggestions for paths for the layperson toward being able to reason and intuit about this stuff at one level beyond pop physics claptrap? I have heard "the theoretical minimum" suggested in the past, but I haven't heard from anyone who has actually used it to go from zero to say, general relativity, only people who think it sounds good. It also seems like a steep investment -- I just…

Feynman's lectures of physics are good for layman explanations, however they quickly feel lacking without the maths background, which you can fill in with The Theoretical Minimum. There's actually a video lecture series of the Theoretical Minimum series that you might find more approachable, that is if you haven't heard of it: https://www.youtube.com/view_play_list?p=189C0DCE90CB6D81 (Here for the general relativity…

Feynman's lectures were delivered to an audience of graduates and faculty who had signed up for an introductory course because Feynman was teaching it. Reading the Feynman lectures without the math background will end up confusing you horribly - I know this because I've found them not-exactly-light reading even though I already (supposedly) know what they're about!

Re: Eldar Black Holes

#83

Post by neilsimp1 »

LoSboccacc wrote: post #4

Wonder if they also explored the possibility that we are in a black hole and the universe structure is recursive. Maybe the background radiation is the part of the hawking radiation that falls inward. And we perceive it infinite but it’s the dilatated space between the hevent horizon and the naked singularity at the center. And the big bang was the supernova that left the black hole. Trippinng!

I've always liked toying with the idea (in my own head, not an astrophysicist) that space is cyclical, or in your words, recursive.

I love animations where it zooms out farther and farther into space, until it gets to the point where galaxies start to resemble molecular structures.

And then of course The Simpson's did a couch gag where exactly this happens and they zoom out and out into space until it finally zooms out of Homer's own head.

Re: Eldar Black Holes

#84

Post by bArray »

Wouldn't the aliens just need to wait for the black hole to evaporate in order to escape? We're talking a long time, but still possible? If it was planned just right, perhaps they could make it so they emerge in the new Universe.

Also, isn't the assumption that there is a "big crunch" (also a good name for a cereal if it doesn't exist)? We're not sure whether there is a big crunch or heat death? This still seems plausible whether there is a big crunch or heat death - either way a black hole may be the only way for a civilization to stay alive at "the end".

Re: Eldar Black Holes

#85

Post by simonh »

bArray wrote: post #84

Wouldn't the aliens just need to wait for the black hole to evaporate in order to escape? We're talking a long time, but still possible? If it was planned just right, perhaps they could make it so they emerge in the new Universe. Also, isn't the assumption that there is a "big crunch" (also a good name for a cereal if it doesn't exist)? We're not sure whether there is a big crunch or heat death? This still seems plau…

Being emitted as undifferentiated Hawking radiation, after the black hole has shrunk to microscopic size, and when it finaly ceases to exist doesn't sound like much of a happy ending.

Re: Eldar Black Holes

#86

Post by darkmighty »

dcow wrote: post #79
krapp wrote: post #26

Earlier quoted context omitted.

>What about the strange UFO occurences that pentagon acknowledged, are we getting visits from aliens within our universe or from another universe? The Pentagon has never acknowledged the existence of extraterrestrial craft, or of UFOs as being anything but hoaxes and misidentified, mundane phenomena. >but how could Buddha have known that blackholes existed? He didn't, any more than the Norse knew that wormholes exist…

I agree, but remember our science today will look like Norse mythology in 1000 years too.

Like Newton's Principia (from 1684) looks like Norse mythology? It is still a valid model except for a few minor errors, and almost halfway to 1000 years. Better yet might be Greek mathematics, e.g. Euclid's Elements which is more than 2300 years old now. The language is different of course, but the content itself reads a lot like a good proof-oriented geometry textbook.

Re: Eldar Black Holes

#87

Post by brianberns »

grondilu wrote: post #8

There is a fascinating PBS Space Time video[1] about black holes that questions the very existence of whatever is "inside" a black hole. They point out that as you approach a black hole, your proper time is advancing slower and slower when compared to an observer located far away from the black hole (like us, on Earth). That means that from the point of view of this far observer, nothing happens inside a black hole u…

Our own past (say, 1974, for example) is also “separated from us not by a space-like frontier, but a time-like one“. Would you say that the past is not real?

Re: Eldar Black Holes

#88

Post by grondilu »

brianberns wrote: post #87
grondilu wrote: post #8

There is a fascinating PBS Space Time video[1] about black holes that questions the very existence of whatever is "inside" a black hole. They point out that as you approach a black hole, your proper time is advancing slower and slower when compared to an observer located far away from the black hole (like us, on Earth). That means that from the point of view of this far observer, nothing happens inside a black hole u…

Our own past (say, 1974, for example) is also “separated from us not by a space-like frontier, but a time-like one“. Would you say that the past is not real?

The frontier I was talking about is impassable. It's "infinitely in the future", aka "never". That's a whole different level of frontier, imho.

Granted, there is a bit of tree falling[1] conundrum here, but that does not make the question less interesting (arguably, it even makes it all the more so).

1. https://en.wikipedia.org/wiki/If_a_tree_falls_in_a_forest

Re: Eldar Black Holes

#89

Post by codelieb »

whatshisface wrote: post #82
fao_ wrote: post #25

Earlier quoted context omitted.

Feynman's lectures of physics are good for layman explanations, however they quickly feel lacking without the maths background, which you can fill in with The Theoretical Minimum. There's actually a video lecture series of the Theoretical Minimum series that you might find more approachable, that is if you haven't heard of it: https://www.youtube.com/view_play_list?p=189C0DCE90CB6D81 (Here for the general relativity…

Feynman's lectures were delivered to an audience of graduates and faculty who had signed up for an introductory course because Feynman was teaching it. Reading the Feynman lectures without the math background will end up confusing you horribly - I know this because I've found them not-exactly-light reading even though I already (supposedly) know what they're about!

The introductory physics course for which Feynman lectured in 1961-63 is part of Caltech's core curriculum, required of all undergraduate students. It was taken by the entire freshman class in 1961-62, and the same people, then sophomores, in 1962-63. The course consists of 3 parts: lectures, recitation sections, and labs. The recitation sections and labs are mandatory, but the lectures are not, and many Caltech students - particularly those who do not understand English well - choose not to attend all the lectures. Attrition in Feynman's lectures was typical for this course: an average of about 10%-20% of the students did not attend any given lecture. However, I would like to inform the poster that graduate students and faculty do not "sign up" for this course - that is not possible. Some graduate students and a few faculty members sometimes attended Feynman's lectures, almost all of whom were leading recitation sections or working in the course's labs. The ratio of undergraduate students to others who attended Feynman's lectures was very large, as you can see for yourself in this photo taken during a typical lecture (the ones with ties are faculty): http://www.feynmanlectures.info/FLP%20Classroom.JPG . For more information please see http://www.feynmanlectures.info/popular_misconceptions_about... . Michael A. Gottlieb, Editor, The Feynman Lectures on Physics New Millennium Edition

Re: Eldar Black Holes

#90

Post by v_lisivka »

dghughes wrote: post #34

From one of the article links, " aliens can live inside black holes." >They would also be brightly illuminated by the central singularity and by photons trapped in the same orbit. That sounds creepily like a typical description of heaven. Timeless, ageless, godlike beings all in a region of intense uniform brightness.

Moreover, we are on the dark side of black hole, and we have cookies. J
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