Following is passage re-quotes (not always in original sequence) + comments on paddoboy's Opus Quotus in post #495 here, itself taken from here.

And here's the rub. It directly implies the rest of the universe has become infinitely old, just at that infaller's proper-time EH crossing.

As some here are aware I reject GR anyway and consider the above issues as all consequences of working from a wrong starting premise. However I choose to work here from within the confines of GR just to point out that even from that premise the infall-to-singularity scenario has, err... holes in it other than just a black one!

Am aware one or two others here have made similar observations to above before, at least in part. This is an attempt to put things together somewhat coherently and inclusively. While tempted to plea for input from just those who 'know GR', that is expecting far too much from the free-for-all that is SF. So am bracing for a time and energy wasting flurry of 2-cents worth views worth exactly 2-cents less than that, and of course the traditional massive side-tracking. One last thing - if anyone wishes to 'pole the Profs' like in that other thread, fine, but do consider reaching a fresh bunch - one can wear out a welcome.

Within the context of GR above is logically coherent up to the point of crossing EH but only for a thoroughly idealized and unrealistic hypothetical case. A so-called 'eternal Schwarzschild BH' existing in an otherwise totally empty and eternal universe. Ignoring the difficult case of a 'realistic' stellar-collapse BH and sticking with our 'eternal' BH, it has problems when plunked into our real, non-empty universe. Admitting in CMBR, possible future mergers etc. perturbs the unreal ideal case by varying and possibly drastic amounts. Since the final BH mass M now becomes an unknowable but increased parameter - ignoring next point. Further admitting the notion of Hawking radiation (i.e. bringing in QM) destroys validity of that 'neat' scenario entirely. More on all that below.Won't it take forever for you to fall in? Won't it take forever for the black hole to even form?

Not in any useful sense. The time I experience before I hit the event horizon, and even until I hit the singularity—the "proper time" calculated by using Schwarzschild's metric on my worldline—is finite. The same goes for the collapsing star; if I somehow stood on the surface of the star as it became a black hole, I would experience the star's demise in a finite time.

Last part not true and in fact self-contradicted by later passage:On my worldline as I fall into the black hole, it turns out that the Schwarzschild coordinate called t goes to infinity when I go through the event horizon. That doesn't correspond to anyone's proper time, though; it's just a coordinate called t.

At large distances t does approach the proper time of someone who is at rest with respect to the black hole.

**There's the admission**. But note what's actually implied there is not t*as a moment in time*but ∂/∂t i.e.*clock-rate*. Now comes the obfuscation:Strictly true but irrelevant and worse downright misleading. There has been a subtle switch-and-bait from talking (implied) relative clock-But there isn't any non-arbitrary sense in which you can call t at smaller r values "the proper time of a distant observer," since in general relativity there is no coordinate-independent way to say that two distant events are happening "at the same time." The proper time of any observer is only defined locally.

**rates**, to relative*moments in time*. The relative time *rates* vary unambiguously (in given scenario) as above quoted admission had to logically acknowledge. That's what matters re free-fall scenario. And such variance can be shown to be perfectly objective - 'real' - as the author acknowledges further below:Quite so - but hardly 'a temporal trick'! With a little careful thought applied, it's seen to thoroughly undermines the notion of finite proper time free-fall to the dreaded 'singularity'. Far from free-fall somehow cancelling above hovering observer scenario out, itAll this is not to imply that the black hole can't also be used for temporal tricks much like the "twin paradox" mentioned elsewhere in this FAQ. Suppose that I don't fall into the black hole—instead, I stop and wait at a constant r value just outside the event horizon, burning tremendous amounts of rocket fuel and somehow withstanding the huge gravitational force that would result. If I then return home, I'll have aged less than you. In this case, general relativity can say something about the difference in proper time experienced by the two of us, because our ages can be compared locally at the start and end of the journey.

*exacerbates*. Assuming free-fall equivalent to being 'from infinity', it's easily shown that relative to a momentarily co-located hovering observer (we assume close to the EH), the free-faller suffers an additional SR time dilation factor numerically equal to the purely GR frequency redshift factor √(g_00) suffered by the hoverer (as referenced to a distant coordinate observer - 'the rest of the universe'). Hence the net, in-principle objectively determinable, valid time dilation as clock-rate, of in-faller relative to coordinate observer ('rest of universe') is the product of those GR and SR factors i.e. √(g_00)^2 = g_00 . On top of that an additional, longitudinal Doppler-shift factor √(g_00) yields the in-faller's net optical redshifted output perceived by a coordinate observer. So although it's strictly true the net perceived redshift is, by just that additional factor 'illusory', it hardly matters as the objectively determinable time dilation factor (as clock-rate), g_00, has become zero at the EH crossing. None of this requires in-depth knowledge of GR, just logical application of the basics.And here's the rub. It directly implies the rest of the universe has become infinitely old, just at that infaller's proper-time EH crossing.

*Not imo a sensible scenario*. Somehow the infaller is due for a rude shock - at that point if not 'much' sooner. That the notion a further 'care-free' (sans spaghettification) infall to 'singularity' can make a shred of sense is laughable. Or - what's infinitely more infinite (EH to singularity) than what's already infinite (far outside to EH) as objectively determined by the rest of the universe? Utter nonsense imo. At this point of realization, some will try and rescue the case by invoking Hawking radiation which if it exists will radically alter the case from infaller's proper time pov. In fact, assuming the 'traditional' view that an infaller will see no Hawking radiation, the modified scenario logically has him/her riding a shrinking EH down to zero size and the 'singularity' per se is never encountered. And it occurs in typically huge but finite 'rest of universe' time which at least has some sanity to it.Well things sure do get weird using Schwarzschild coordinates and assuming that unrealistic eternal BH. Please folks, don't drag in here even weirder exotica like 'firewalls' which concept imo just reeks of desperation and/or one-upmanship among ivory-tower theorists.In fact, inside the event horizon, t is actually a spatial direction, and the future corresponds instead to decreasing r. It's only outside the black hole that t even points in a direction of increasing time. In any case, this doesn't indicate that I take forever to fall in, since the proper time involved is actually finite.

As some here are aware I reject GR anyway and consider the above issues as all consequences of working from a wrong starting premise. However I choose to work here from within the confines of GR just to point out that even from that premise the infall-to-singularity scenario has, err... holes in it other than just a black one!

Am aware one or two others here have made similar observations to above before, at least in part. This is an attempt to put things together somewhat coherently and inclusively. While tempted to plea for input from just those who 'know GR', that is expecting far too much from the free-for-all that is SF. So am bracing for a time and energy wasting flurry of 2-cents worth views worth exactly 2-cents less than that, and of course the traditional massive side-tracking. One last thing - if anyone wishes to 'pole the Profs' like in that other thread, fine, but do consider reaching a fresh bunch - one can wear out a welcome.

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