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Eldar Black Holes

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Re: Eldar Black Holes

#121

Post by samstave »

pbhjpbhj wrote: post #103
neilsimp1 wrote: post #83

Earlier quoted context omitted.

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 o…

Learning of atoms initially I was given an orbital model, like a solar system, who caused/allowed me to form a similar idea (I think it's quite common?) that solar systems could be atoms in a super-universe. I was so annoyed as a teenager to find that atoms aren't really little solar systems.

When I was ten years old I was meditating and thinking about how each one our consciences are a neuron in gods brain... I will never forget that epiphany as it was before I had studied any philos etc

Re: Eldar Black Holes

#123

Post by machinshin_ »

> There was a second, unrelated paper that suggests that aliens can live inside black holes.

[ ... snip ... ]

> In theory, highly advanced aliens could live on such planets, being unobservable from outside while exploiting the high energies and large time dialtions available.

reminds me of Frederick Pohl's Heechee Saga.

Re: Eldar Black Holes

#124

Post by sterlind »

krapp wrote: post #111
JonnyNova wrote: post #44

Earlier quoted context omitted.

The US government hasn't acknowledge the existence of aliens, but in 2016 the CIA admitted to funding programs because they suspected the existence of aliens. It is very hard to find a good source to link though due to terrible SNR when you google "cia aliens"

The government also studied remote viewing, and the Air Force had its own UFO project called Operation Blue Book, and of course there was MKULTRA looking into mind control, but just because something is studied doesn't mean it exists, or gives practical results.

Sundevil (remote viewing) and Blue Book (UFOs) were '60s projects. AATIP and the UAP footage has been confirmed by the Pentagon itself, and even Raytheon's official site talks up the use of their ATFLIRs in recording the footage:

https://www.raytheon.com/news/feature/uap_atflir

We don't know if the footage is aliens, but we do know that the footage is real.

Re: Eldar Black Holes

#125

Post by AgentME »

shullbitt0r wrote: post #115
AgentME wrote: post #104

Earlier quoted context omitted.

I think you've got it backwards. As on object approaches a black hole, an outside observer will see that object's clock slow down and eventually stopping as it hits the event horizon. Conversely, the object falling into the black hole will see the rest of the universe's clocks speed up. It could watch stars (far from the black hole) be born and die. If you take a trip close to a black hole's event horizon and then fl…

> As on object approaches a black hole, an outside observer will see that object's clock slow down and eventually stopping as it hits the event horizon. So I had the idea that smaller black holes are at the center of the sun, the earth and so on, being the principle source of gravity and the "movement" that we see is just us falling into different black holes at the same time, which are also falling into each other.…

It's really reaching a lot to assume black holes are the sole source of gravity or time. (If you want to distill it really far, I think it's more right to say they counteract time than that they cause or provide it. You go near a black hole, and you age less and have less time to do things between the times of external events not near the black hole.)

>So micro black holes must be at the center of massive particles too.

If an object has a schwarzschild radius smaller than its own radius, then it isn't a black hole. That literally describes all non-black-hole objects with mass. That's just the standard manifestation of gravity.

>The world line of a photon on the other hand is just the intersection of two event horizons as they grow, so you get a wave model. And that's why you have entanglement: circles have two intersections, so if your model is two dimensional, you get two entanglements.

Is there any connection here besides that an event horizon and the sum of all possible paths of a photon in a given amount of time are both spheres?

If there were a micro-black-hole inside of a particle, its event horizon would have to be within the particle, or else the particle would just be indistinguishable from a black hole. The particle wouldn't be like a normal particle with an invisible spherical event horizon surrounding it and affecting its interactions.

Re: Eldar Black Holes

#126

Post by analog31 »

Balgair wrote: post #96
analog31 wrote: post #40

Earlier quoted context omitted.

Here's something I've wondered about black holes, related to what's inside. Simplistically, there must be mass inside, i.e., every black hole has a mass that can somehow be measured, e.g., by orbital velocities of satellites. And the mass-energy has to equal the mass-energy that has fallen in. So far so good. But the stuff that falls in is not purely described by its mass. It also has angular momentum, electrical cha…

The main issue is that you cannot just put a voltmeter or other devices/methods near a BH. Not that you can't do it in a Gedankenexperiment way, of course, but in a relativistic way. Because of General & Special Relativity, things like volts and amps, charge and mass, they get 'bent' in this weird non-intuitive way. In our own (slow) world, electro-magnetism is one of those 'weird things' that comes out of special re…

Thanks. I actually got started in Meisner, Thorne, and Wheeler, and it's a slog. I've asked some physicists if they know of an easier textbook, but there doesn't seem to be one. I'm a physicist too, but my willingness to build outrageous experiments made up for my lack of theoretical agility. Still, I'd love to understand gravitation.

I've still got my copy of Jackson from grad school. ;-)

Re: Eldar Black Holes

#127

Post by wallace_f »

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".

I've never been able to feel comfortable understanding reference frames. Even considering simpler examples: So what if a probe is launched to catch our solar system's recent cigar-shaped visitor. Assume we catch it and want to bring back a sample of equal mass to the probe. So what determines the kinetic energy required to return this sample to earth? Is the delta relative to that of the probe, to the solar system, or to its origin? What if it is was accelerated to 0.1c relative to its launch site in another galaxy, but is only travelling at 0.001c relative to us?

Common sense dictates that the probe and the sample would require equal fuel to return to earth; but to an observer riding this cigar-rock, why would the universe cut our probe some slack if we changed its kinetic energy rather than the observer?

Re: Eldar Black Holes

#128

Post by ajnin »

olegkikin wrote: post #12
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…

That's the thing that never made sense to me about the black holes. The closer you are to the event horizon, the faster the time passes for the universe around you. So reaching the event horizon should take infinite amount of the "outside time", so right before you reach the horizon, you should see the whole future of the universe, including its end, if there's any. So how do black holes gain any mass then?

I think one way for matter to reach the black hole might be that when more matter comes close to the black hole the event horizon expands, so that matter that is already close to the event horizon gets incorporated even without moving. I don't know what happens to the matter that gets inside that way, does it remain stuck, giving an onion-like structure to the black hole, or something else ?

Re: Eldar Black Holes

#129

Post by auntienomen »

analog31 wrote: post #126
Balgair wrote: post #96

Earlier quoted context omitted.

The main issue is that you cannot just put a voltmeter or other devices/methods near a BH. Not that you can't do it in a Gedankenexperiment way, of course, but in a relativistic way. Because of General & Special Relativity, things like volts and amps, charge and mass, they get 'bent' in this weird non-intuitive way. In our own (slow) world, electro-magnetism is one of those 'weird things' that comes out of special re…

Thanks. I actually got started in Meisner, Thorne, and Wheeler, and it's a slog. I've asked some physicists if they know of an easier textbook, but there doesn't seem to be one. I'm a physicist too, but my willingness to build outrageous experiments made up for my lack of theoretical agility. Still, I'd love to understand gravitation. I've still got my copy of Jackson from grad school. ;-)

There are lots of easier textbooks, all of them less...wordy. Wald's is the industry standard these days. Schutz, Carroll, and D'Inverno are all good introductions. If you're really pressed for time, Dirac wrote an intro to GR which is about as short as humanly possible. It omits most of the geometry though.

Re: Eldar Black Holes

#130

Post by analog31 »

auntienomen wrote: post #129
analog31 wrote: post #126

Earlier quoted context omitted.

Thanks. I actually got started in Meisner, Thorne, and Wheeler, and it's a slog. I've asked some physicists if they know of an easier textbook, but there doesn't seem to be one. I'm a physicist too, but my willingness to build outrageous experiments made up for my lack of theoretical agility. Still, I'd love to understand gravitation. I've still got my copy of Jackson from grad school. ;-)

There are lots of easier textbooks, all of them less...wordy. Wald's is the industry standard these days. Schutz, Carroll, and D'Inverno are all good introductions. If you're really pressed for time, Dirac wrote an intro to GR which is about as short as humanly possible. It omits most of the geometry though.

Thanks. I do want the geometry, but I just don't want to get killed by it. ;-)
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