Go Back   Science Forums Biology Forum Molecular Biology Forum Physics Chemistry Forum > General Science Forums > Physics Forum
Register Search Today's Posts Mark Forums Read

Physics Forum Physics Forum. Discuss and ask physics questions, kinematics and other physics problems.


Can you get out of a black hole?

Can you get out of a black hole? - Physics Forum

Can you get out of a black hole? - Physics Forum. Discuss and ask physics questions, kinematics and other physics problems.


Reply
 
LinkBack Thread Tools Display Modes
  #1  
Old 10-28-2005, 05:27 PM
deanbrown3d@yahoo.com
Guest
 
Posts: n/a
Default Can you get out of a black hole?



Suppose I'm in a black hole, just beneath the event horizon, and I want
to get out.

A second black hole is approaching mine fast and at a skew angle, and
as it nears me the gravitational pull between the two balances out
partially, thus allowing me to escape by following a path perpendicular
to the line between the two hole centers. Is not the escape velocity
reduced to below that of the speed of light in this case?

Dean

Reply With Quote
  #2  
Old 10-28-2005, 06:18 PM
tadchem
Guest
 
Posts: n/a
Default Can you get out of a black hole?


[Only registered users see links. ] wrote:

You're in deep.


Now you're in even deeper.


No. It is raised. Your black holes have merged and you didn't even have
the wherewithal to get out of even the first hole. Now the hole has
gotten even deeper.

If you can get a message out, tell us what it's like to be dead.

Tom Davidson
Richmond, VA

Reply With Quote
  #3  
Old 10-28-2005, 06:45 PM
dean
Guest
 
Posts: n/a
Default Can you get out of a black hole?

Its not merging with my black hole. Its just skimming past, and will
continue on after this slight change in direction. As it approaches, it
pushes my event horizon back, because of net gravitational
counter-field.

If it pushes my event horizon back past where I am, then I'm out of
there!

Reply With Quote
  #4  
Old 10-28-2005, 07:06 PM
tadchem
Guest
 
Posts: n/a
Default Can you get out of a black hole?


dean wrote:

That is what *you* may think. Black holes merge.


No. It pulls your event horizon away, making it larger. An event
horizon is not pushed by anything. It has no mass and is not subject
to ANY forces. It is a mathematical locus - a locus of points where
the escape velocity (read the scalar gravitational potential) is such
that light cannot escape.

Gravitational fields are scalar potential fields, so they add. If a
second black hole comes near and *adds* its gravitational field to that
of the first, the hole gets *deeper*.


Each will pull the event horizon of the other out towards itself. If
the two event horizons ever touch, the black holes will instantly merge
like two holes in space-time.

You can make an event horizon larger by adding to the gravitational
field. To make an event horizon *smaller* you would have to subtract
from the gravitational field. There is no way to do that known to
modern physics. Even 'anti-matter' has positive mass-energy.

Tom Davidson
Richmond, VA

Reply With Quote
  #5  
Old 10-28-2005, 07:59 PM
dean
Guest
 
Posts: n/a
Default Can you get out of a black hole?

This doesn't make sense yet to me. Suppose I am in hole H1 and we have
a linear orientation of:

H2-H1-Me

Both black holes H1 and H2 are on one side of me, that adds to the
gravitational force on me left. H2 simply added to the G force on my
left. Hence it is even harder for me to go right and escape.

Now put me in the middle at some instance in time so its:

H2-Me-H1

Until H1 came along, I was stuck, just below the event horizon (E.H.)
of H2. But now there is a gravitational field on the other side,
pulling me out, so it has placed the E.H. of H2 further left,
potentially past me. So, supposing earlier I just didn't have enough
energy to get out of H2, while this other hole is passing by I now do
have sufficient energy (in my rocket) to get at least into the other
hole, and preferably out completely, being balanced between two large
gravitational fields. If the incoming hole is much bigger than the one
I am in, it may suck some material from it, just as a planet can
capture a moon or some dust if it comes close to another planet.

Reply With Quote
  #6  
Old 10-28-2005, 08:04 PM
dean
Guest
 
Posts: n/a
Default Can you get out of a black hole?

oops I got that last paragraph backwards, it should say:

H1-Me-H2

Until H2 came along, I was stuck, just below the event horizon (E.H.)
of H2. But now there is a gravitational field on the other side,
pulling me out, so it has placed the E.H. of H1 further left,
potentially past me. So, supposing earlier I just didn't have enough
energy to get out of H1, while this other hole is passing by I now do
have sufficient energy (in my rocket) to get at least into the other
hole, and preferably out completely, being balanced between two large
gravitational fields. If the incoming hole H2 is much bigger than the
one
I am in, it may suck some material from it, just as a planet can
capture a moon or some dust if it comes close to another planet.

Reply With Quote
  #7  
Old 10-28-2005, 08:06 PM
dean
Guest
 
Posts: n/a
Default Can you get out of a black hole?

Dammit! I got that last paragraph wrong again, it should say:


H1-Me-H2


Until H2 came along, I was stuck, just below the event horizon (E.H.)
of H1. But now there is a gravitational field on the other side,
pulling me out, so it has placed the E.H. of H1 further left,
potentially past me. So, supposing earlier I just didn't have enough
energy to get out of H1, while this other hole is passing by I now do
have sufficient energy (in my rocket) to get at least into the other
hole, and preferably out completely, being balanced between two large
gravitational fields. If the incoming hole H2 is much bigger than the
one
I am in, it may suck some material from it, just as a planet can
capture a moon or some dust if it comes close to another planet.

Reply With Quote
  #8  
Old 10-28-2005, 08:32 PM
dean
Guest
 
Posts: n/a
Default Can you get out of a black hole?

Suppose I am in black hole H1 in the linear orientation

H2-H1-Me

H2 adds to the gravitational force on my left and pushes the event
horizon on my right further away from me (things are worse).

Now consider when the new black hole H2 is on the other side of me:

H1-Me-H2


Until H2 came along, I was stuck, just below the event horizon (E.H.)
of H1. But now there is a gravitational field on the other side,
pulling me out, so it has placed the E.H. of H1 further left,
potentially past me. So, supposing earlier I just didn't have enough
energy to get out of H1, while this other hole is passing by I now do
have sufficient energy (in my rocket) to get at least into the other
hole, and preferably out completely, being balanced between two large
gravitational fields. If the incoming hole H2 is much bigger than the
one
I am in, it may suck some material from it, just as a planet can
capture a moon or some dust if it comes close to another planet

Reply With Quote
  #9  
Old 10-28-2005, 08:48 PM
Steve Ralph
Guest
 
Posts: n/a
Default Can you get out of a black hole?


"dean" <[Only registered users see links. ]> wrote in message
news:1130531563.983485.308910@z14g2000cwz.googlegr oups.com...

In which case you are not in a black hole to start with.

sr



Reply With Quote
  #10  
Old 10-28-2005, 09:56 PM
dean
Guest
 
Posts: n/a
Default Can you get out of a black hole?

No - the other H2 has approached mine since I became stuck.

Reply With Quote
Reply

Tags
black , hole


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
What is Gravity? sdr@sdrodrian.com Physics Forum 1 01-27-2008 02:53 PM
Politics And Cannibalism? Introducing The Dourties, Chelsea, Bill, Hillary, Barrack Obama, George Bush, Jr., And All Of Capital Hill! jon_johnfrancisayres@yahoo.com Microbiology Forum 0 10-06-2007 05:59 AM
How can a black hole "evaporate"? e goldstein Physics Forum 1 02-05-2005 12:58 AM
Information Can Leave A Black Hole James Briggs Physics Forum 4 12-18-2003 06:54 AM


All times are GMT. The time now is 06:55 PM.


Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Copyright 2005 - 2012 Molecular Station | All Rights Reserved
Page generated in 0.20769 seconds with 16 queries