![](/i/fill.gif) |
![](/i/fill.gif) |
|
![](/i/fill.gif) |
|
![](/i/fill.gif) |
| ![](/i/fill.gif) |
| ![](/i/fill.gif) |
|
![](/i/fill.gif) |
|
![](/i/fill.gif) |
| ![](/i/fill.gif) |
| ![](/i/fill.gif) |
|
![](/i/fill.gif) |
Ok, another physics question. Not related to the Big Bang, but I didn't
want to create a new thread.
It seems that a black hole can be characterized by three (and only three)
quantities: its mass, angular momentum and electric charge. For example the
Reissner-Nordstr?m metric is a solution to the general relativity equations
for a charged, non-rotating black hole.
I don't understand. Electric charge is mediated by photons. Photons cannot
escape a black hole. How can they mediate anything in this case? A black
hole swallows photons, it doesn't exchange them with anything.
--
- Warp
Post a reply to this message
|
![](/i/fill.gif) |
| ![](/i/fill.gif) |
| ![](/i/fill.gif) |
|
![](/i/fill.gif) |
|
![](/i/fill.gif) |
| ![](/i/fill.gif) |
| ![](/i/fill.gif) |
|
![](/i/fill.gif) |
And lo On Thu, 18 Nov 2010 15:53:38 -0000, Warp <war### [at] tag povray org> did
spake thusly:
> This has puzzled me for a while, and I can't find an answer.
>
> There was a time during the beginning of the Universe, when all the
> energy in the Universe was compressed into a space smaller than its own
> Schwarzschild radius.
As an aside to some the Big Bang theory is being dropped or at least the
part where it derives from a singularity is.
There's inflationary theory (or theories) by which a quantum fluctuation
inflates.
String theory (or the over-riding M-theory) whereby any attempt to
compress an object beyond the Planck length will result in it expanding.
and Brane theory in which our universe is caused by either a collision or
merging of two (or more) multi-dimensional 'sheets'.
All remove the need for a singularity.
As for your initial question, the calculations for the Schwarzschild
radius don't apply to a rapidly expanding mass. As you put it the
expansion out-runs the gravitational curve.
--
Phil Cook
--
I once tried to be apathetic, but I just couldn't be bothered
http://flipc.blogspot.com
Post a reply to this message
|
![](/i/fill.gif) |
| ![](/i/fill.gif) |
| ![](/i/fill.gif) |
|
![](/i/fill.gif) |
|
![](/i/fill.gif) |
| ![](/i/fill.gif) |
| ![](/i/fill.gif) |
|
![](/i/fill.gif) |
Le 23/11/2010 13:54, Phil Cook v2 a écrit :
> As you put it the expansion out-runs the gravitational curve.
I'm just nuts, and 10 cards short of full deck.
It seems gravitation has always been considered as "attraction between 2
objetcs".
What if, instead, it was just the universe which was repelling, and the
"mass" of the other object was in fact a shield against that repulsion.
(the more energy in the shield, the more protection it provide. and it
is just fine with delta-e=delta-m.c², but as a shield it only divert the
repelling flux: none get created, none get destroyed)
Remember the old joke: Gravity is a myth, the Earth sucks.
Well, in fact, it's just the universe which is blowing instead.
Gravity is a myth, the sky is pressuring you down!
Hence there is no graviton to find for the "fifth" force.
It's just made up from the known ones (the 4 united...)
Post a reply to this message
|
![](/i/fill.gif) |
| ![](/i/fill.gif) |
| ![](/i/fill.gif) |
|
![](/i/fill.gif) |
|
![](/i/fill.gif) |
| ![](/i/fill.gif) |
| ![](/i/fill.gif) |
|
![](/i/fill.gif) |
Le_Forgeron wrote:
> What if, instead, it was just the universe which was repelling, and the
> "mass" of the other object was in fact a shield against that repulsion.
Already considered and tested. You would weigh less on the "back" of the
earth than the "front" because the earth was blocking repulsion particles
that are assumedly not moving along with the earth in its orbit.
Also, the "everything is expanding, so if you jump you don't fall but rather
the earth and your feet expand towards each other" theory can be trivially
disproven as well.
> Hence there is no graviton to find for the "fifth" force.
> It's just made up from the known ones (the 4 united...)
I'm pretty sure gravity is one of four, not five. :-)
--
Darren New, San Diego CA, USA (PST)
Serving Suggestion:
"Don't serve this any more. It's awful."
Post a reply to this message
|
![](/i/fill.gif) |
| ![](/i/fill.gif) |
| ![](/i/fill.gif) |
|
![](/i/fill.gif) |
|
![](/i/fill.gif) |
| ![](/i/fill.gif) |
| ![](/i/fill.gif) |
|
![](/i/fill.gif) |
On 23-11-2010 17:12, Darren New wrote:
> Le_Forgeron wrote:
>> What if, instead, it was just the universe which was repelling, and the
>> "mass" of the other object was in fact a shield against that repulsion.
>
> Already considered and tested. You would weigh less on the "back" of the
> earth than the "front" because the earth was blocking repulsion
> particles that are assumedly not moving along with the earth in its orbit.
>
> Also, the "everything is expanding, so if you jump you don't fall but
> rather the earth and your feet expand towards each other" theory can be
> trivially disproven as well.
>
>> Hence there is no graviton to find for the "fifth" force.
>> It's just made up from the known ones (the 4 united...)
>
> I'm pretty sure gravity is one of four, not five. :-)
>
The one who left before they became famous.
Post a reply to this message
|
![](/i/fill.gif) |
| ![](/i/fill.gif) |
| ![](/i/fill.gif) |
|
![](/i/fill.gif) |
|
![](/i/fill.gif) |
| ![](/i/fill.gif) |
| ![](/i/fill.gif) |
|
![](/i/fill.gif) |
Le_Forgeron <lef### [at] free fr> wrote:
> It seems gravitation has always been considered as "attraction between 2
> objetcs".
Actually since about 1915 gravitation has been considered a side-effect
of the geometry of spacetime.
--
- Warp
Post a reply to this message
|
![](/i/fill.gif) |
| ![](/i/fill.gif) |
| ![](/i/fill.gif) |
|
![](/i/fill.gif) |
|
![](/i/fill.gif) |
| ![](/i/fill.gif) |
| ![](/i/fill.gif) |
|
![](/i/fill.gif) |
On 23/11/2010 4:29 PM, andrel wrote:
>> I'm pretty sure gravity is one of four, not five. :-)
>>
>
> The one who left before they became famous.
LOL
--
Regards
Stephen
Post a reply to this message
|
![](/i/fill.gif) |
| ![](/i/fill.gif) |
| ![](/i/fill.gif) |
|
![](/i/fill.gif) |
|
![](/i/fill.gif) |
| ![](/i/fill.gif) |
| ![](/i/fill.gif) |
|
![](/i/fill.gif) |
On 23/11/2010 12:54 PM, Phil Cook v2 wrote:
> As an aside
As an aside to your aside:
http://www.bbc.co.uk/news/science-environment-11837869
--
Regards
Stephen
Post a reply to this message
|
![](/i/fill.gif) |
| ![](/i/fill.gif) |
| ![](/i/fill.gif) |
|
![](/i/fill.gif) |
|
![](/i/fill.gif) |
| ![](/i/fill.gif) |
| ![](/i/fill.gif) |
|
![](/i/fill.gif) |
> It seems gravitation has always been considered as "attraction between 2
> objetcs".
>
> What if, instead, it was just the universe which was repelling, and the
> "mass" of the other object was in fact a shield against that repulsion.
The most intriguing thing for me is the speeds of stars relative to the
centre of the galaxy, they don't follow the expected pattern by simply
solving the math for orbits:
http://en.wikipedia.org/wiki/Dark_matter_halo
Post a reply to this message
|
![](/i/fill.gif) |
| ![](/i/fill.gif) |
| ![](/i/fill.gif) |
|
![](/i/fill.gif) |
|
![](/i/fill.gif) |
| ![](/i/fill.gif) |
| ![](/i/fill.gif) |
|
![](/i/fill.gif) |
scott wrote:
> http://en.wikipedia.org/wiki/Dark_matter_halo
"either the halo is composed of weakly-interacting elementary particles
known as WIMPs, or it is home to large numbers of small, dark bodies known
as MACHOs."
I really think the scientists need to knock this sort of stuff off. 500
years from now, people will still be using these names.
For a fun fictional take on the problem, check out Robert Sawyer's
"StarPlex" novel. :-)
--
Darren New, San Diego CA, USA (PST)
Serving Suggestion:
"Don't serve this any more. It's awful."
Post a reply to this message
|
![](/i/fill.gif) |
| ![](/i/fill.gif) |
| ![](/i/fill.gif) |
|
![](/i/fill.gif) |
|
![](/i/fill.gif) |
| ![](/i/fill.gif) |