nemesis <nam### [at] gmailcom> wrote:
> >> Perhaps only Phil Connor would know. :P
> >
> > Maybe - I don't know *him*... should I?
>
> Ever seen "Groundhog Day" with Bill Murray?  A classic. :)

Aaah! Of course, yes - that rings a bell. Great movie, liked it a lot!

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nemesis <nam### [at] gmailcom> wrote:
> Well, it's all relative to the observer, so from our point of view the
> universe indeed revolves around us.  Actually, to the common man in the
> streets -- whose view at nights is occluded by both smog polution and
> city lights so he doesn't really take the time to look up the few
> blinking stars so far away and so static -- the universe revolves around
> mundane job, bills and society's many rituals. :P

Yeah, and for too many of them, the world actually revolves around *them* :)

BTW, as a child I pictured that as of course the world is round, then whenever
we would be driving around, the world would revolve below us... and, by the
way, of course mountains would be the places where the earth was "bent" :)

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"clipka" <nomail@nomail> wrote:
> nemesis <nam### [at] gmailcom> wrote:
> > blinking stars so far away and so static -- the universe revolves around
> > mundane job, bills and society's many rituals. :P
>
> Yeah, and for too many of them, the world actually revolves around *them* :)

That's the worst. ;)

> BTW, as a child I pictured that as of course the world is round, then whenever
> we would be driving around, the world would revolve below us... and, by the
> way, of course mountains would be the places where the earth was "bent" :)

hah!

BTW, has any of you guys ever witnessed the Milky Way by your own eyes?  I did
as a pre-teen, one of the most amazing moments in my life, no doubt.  My family
went in vacation to some rural place of sorts and I was roaming around in my
bike until dark at night.  I looked up at the sky and couldn't believe the
sheer amount of stars just above my head!  There were so many that they
gathered in thick luminous regions, which at first I thought were clouds, but
then remembered the sky was clean in the afternoon and looking more closely, it
could be seen very faint flickering in said clouds... quite a moment!  You feel
right in space, in the full glory of a 180% view of the universe... I recommend
any of you at least once to take refuge from noisy and bright cityscapes just to
marvel at this true natural beauty.

It's why I'm so full of passion for astronomic topics... :)

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clipka <nomail@nomail> wrote:
> [-- text/plain, encoding 8bit, charset: iso-8859-1, 19 lines --]

> Warp <war### [at] tagpovrayorg> wrote:
> > clipka <nomail@nomail> wrote:
> > > From an outside observer's frame of reference, the victim not only *appears* to
> > > be "hanging out there", he still physically *is*.
> >
> >   How is he "physically" there? The external observer can't touch him nor
> > communicate with him.

> He can: He can send light pulses to him. And the poor victim can send light
> pulses back.

  No he can't. The light pulses sent by the external observer won't ever
reach the falling object, from the external observer's point of view, for
the exact same reason that it looks to him like the falling object never
crosses the EH.

  The falling object won't be able to send anything back because he is
inside the EH.

> After all, he has not passed the EH yet.

  Of course he has.

-- 
                                                          - Warp

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"nemesis" <nam### [at] gmailcom> wrote:
> BTW, has any of you guys ever witnessed the Milky Way by your own eyes?  I did
> as a pre-teen, one of the most amazing moments in my life, no doubt.

I fancy I did when I was a child - although I can't remember being able to make
out any stars, just a blurry band. Maybe that was because I've been
short-sighted ever since I can remember.

I grew up in a rather small town in a hilly region, spread across multiple
valleys, in a smaller side valley not too close to the town centers, so the air
was very clean, and not too many light sources nearby late at night. Occasionaly
our dad (a teacher) would take us out on a night barbecue with his pupils in an
even more remote spot in the woods around. We also did a few camping vacations
in different European contries (UK, France and Italy), and later took trips
once or twice a year to sparsely populated seaside regions, where we'd often go
for walks after dark.

I loved the stars, and particularly the moon, and looking up at the night sky. I
still enjoy looking up on a clear night when I'm far from the big city I live
in, and marvel in some kind of surprise once again how clear a starry night can
be!

(Unfortunately, nothing so clear though as to identify the milky way as a mass
of stars. Or maybe my glasses just aren't good enough for that.)

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Warp <war### [at] tagpovrayorg> wrote:
> > He can: He can send light pulses to him. And the poor victim can send light
> > pulses back.
>
>   No he can't. The light pulses sent by the external observer won't ever
> reach the falling object, from the external observer's point of view, for
> the exact same reason that it looks to him like the falling object never
> crosses the EH.

Just believe me (or figure out for yourselves): He can...

>   The falling object won't be able to send anything back because he is
> inside the EH.

.... because he isn't.

I'll draw a picture today, to illustrate what's going on with that warped
spacetime. I thought you should know about that, if only for the sake of your
nick ;)

The key to understanding is that a second is not a second. Delta-t is not
universal (just like distance isn't), but rather depends on the frame of
reference.

Likening some time dilation effects to "after-image" effects may make them more
"digestible" to laymen than having them try to imagine how a second cannot be a
second, but it's not *precisely* what's going on.

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clipka <nomail@nomail> wrote:
> >   The falling object won't be able to send anything back because he is
> > inside the EH.

> .... because he isn't.

  So if he isn't inside the EH, that means that actually *nothing* can
ever cross the EH, which means that nothing goes inside a BH, and thus
nothing is "lost" there.

  Great, you have solved the information loss problem. No information
is ever lost to a BH because nothing can enter it. Everything will just
hover endlessly asymptotically close to the EH, and can in fact be
interacted with.

  What are the quantum mechanists complaining about?

-- 
                                                          - Warp

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Warp <war### [at] tagpovrayorg> wrote:
>   So if he isn't inside the EH, that means that actually *nothing* can
> ever cross the EH, which means that nothing goes inside a BH, and thus
> nothing is "lost" there.

That's basically what I think it says, yes.

>   Great, you have solved the information loss problem. No information
> is ever lost to a BH because nothing can enter it. Everything will just
> hover endlessly asymptotically close to the EH, and can in fact be
> interacted with.
>
>   What are the quantum mechanists complaining about?

I have no idea. Ask them :)


BTW, I after having so far worked only with what I picked up and remembered and
imagined, but finding that drawing a proper image based on this information is
not so trivial, I did have a closer look at the Schwarzschild metric details,
finding this on Wikipedia:

----------------------------------------
In Schwarzschild Coordinates, the Schwarzschild metric has the form:

c^2 dT^2 = (1 - r[s]/r) c^2 dt^2 - ... - ...

where

T is the proper time (time measured by a clock moving with the particle) ...
t is the time coordinate (measured by a stationary clock at infinity) ...,
r is the radial coordinate ...
r[s] is the Schwarzschild radius (in meters) of the massive body
....
----------------------------------------
(Note that dT and dt denote time intervals. I stripped the other terms because
they're not easy to represent in ASCII, and are independent of time, so they
can be considered constant for the sake of my arguments.)

There are a few interesting things to note here:

(1) As we approach r = r[s] (the radius of the EH), we'll find that the factor
of the dt^2 term diminishes zero. That means not only that "victim time" slows
down with respect to the "observer time", but that it actually slows down to
zero (or, seen the other way round, "observer time" speeds up to infinity) at
the EH.

Thus, in the observer's reference frame (I'm deliberately avoiding the phrase
"as seen from the observer", because the formula doesn't say anything about
perception, but plain hard facts), as soon as the "victim" would hit the EH,
its time would come to a standstill, so it couldn't move *any* distance in
finite time. (Note however that time slows down so dramatically already very
close to the EH that the "victim" will not even *reach* EH in finite time.)

However, in the "victim's" reference frame, as soon as the "victim" would hit
the EH, the observer's time would speed up to infinity. Again, note that the
speedup would already have reached dramatic values very close to the EH.


(2) Note that the formula is given "in Schwarzschild Coordinates"...
(Uh-huh?!)... Well, this is what Wikipedia has to say about those (emphasis
added):

"The defining characteristic of Schwarzschild chart is that the radial
coordinate possesses a natural geometric interpretation in terms of the SURFACE
AREA and Gaussian curvature of each sphere. However, RADIAL DISTANCES and angles
are NOT ACCURATELY REPRESENTED."

So, the equation does *not* state that the EH has a radius of r[s] = 2GM/c^2
after all. Instead, it states that it has a *surface* of 4 pi (2GM/c^2)^2.

Given that spacetime is notoriously distorted at the EH, this makes *no*
statement whatsoever about its radial distance from the singularity. It could
be - ta-ding! - zero after all...


(Again, I find my theory of "EH=singularity" supported - it will mark a paradigm
shift in the understanding of black holes, and I'm going to be a world-famous
nobel prize winner, named along with Einstein, Hawking and Feinman! GR and QM
will at last be proven false, and MY theory will TAKE OVER THE WORLD... no, THE
*UNIVERSE*! *MUAHAHAHAHA*!)

(Good enough to quality for a world-class crackpot this time, huh? =B))

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"clipka" <nomail@nomail> wrote:
> Another BTW: With contemporary German orthography, "Schwartzschild" would lose
> the "t" in his name... like "Rothschild" (which is "Redshield") would lose the
> "h"...

Duh... sorry folks for misinforming you on this important subject: Looks like
Schwarzschild's "t" *already* got lost in some black hole... must have been
redundant information after all...

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clipka wrote:
> Thus, in the observer's reference frame (I'm deliberately avoiding the phrase
> "as seen from the observer", because the formula doesn't say anything about
> perception, but plain hard facts), as soon as the "victim" would hit the EH,
> its time would come to a standstill, so it couldn't move *any* distance in
> finite time.

I'm not sure that follows. Photons move as fast as possible, and in their 
own reference frame, time has come to a standstill. Why does the victim's 
clock influence the velocity of the victim in the observer's timeframe?

This is like saying I stick a giant engine on a spaceship, turn it on, and 
just go, and after a while you see me slowing down, because my clock is 
getting asymptotically close to stopped from your reference frame.

> (Note however that time slows down so dramatically already very
> close to the EH that the "victim" will not even *reach* EH in finite time.)

*That* is why I think the victim will not find himself inside the EH - the 
universe (including himself) will have decayed to nothingness or some such 
before he gets there.

> So, the equation does *not* state that the EH has a radius of r[s] = 2GM/c^2
> after all. Instead, it states that it has a *surface* of 4 pi (2GM/c^2)^2.

That difference is exactly the warped space. It happens with the sun and the 
earth, too, because of their gravity.

IIRC, I read where the circumference of the (ideal) earth is something like 
a cm shorter than what it should be given the radius, and the sun is a 
kilometer or ten kilometers or some such different.

> Given that spacetime is notoriously distorted at the EH, this makes *no*
> statement whatsoever about its radial distance from the singularity. It could
> be - ta-ding! - zero after all...

More like infinity, methinks.

> (Good enough to quality for a world-class crackpot this time, huh? =B))

I don't think real crackpots go "Mwa ha ha ha!"

-- 
   Darren New, San Diego CA, USA (PST)
   "Ouch ouch ouch!"
   "What's wrong? Noodles too hot?"
   "No, I have Chopstick Tunnel Syndrome."

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