That is easy. A black hole has a radius of R=2Gm/c^2.
A force of c ^ 4 /4G times a distance d gives the same energy E=m c ^ 2
as the one that is contained inside a black hole
of radius R=d, namely c^4 d / ( 2G ).
Let us see if a larger force can appear.
Tom
Apart from the fact that no material is able to withstand this, the argument
was just saying that even if the wire withstands this, strange things
happen at the two ends that make the hole thing impossible:
black holes must appear there.
Tom
This is interesting! I never thought about this.
Can you explain it a bit more?
What acceleration is meant? In what sense
can one say that all mass of the universe is accelerated?
And why don't I feel this gigantic value?
Tom
For a high force to appear near a black hole, a body needs to be
hovering above it, as mentioned above. There are two was to do this:
with a wire and with a rocket engine.
A wire cannot maintain a force c^4/4G: if it did, lovering the wire by
a distance d would create a black hole of...
I guess that the answer would be this: to produce a hovering
in such a situation you would need an extremely powerful engine.
The exhausts from that engine are so massive that the gravitation
they produce cannot be neglected. The claim is that
to produce a force larger than c^4/4G, these...
Hm, I beg to disagree. If there is a maximum force, it must be valid for all observers, even accelerated ones.
But the challenge is to produce a force larger than the claimed limit. It is well known that it is not possible to hover above the horizon (after all this is a black hole); so this...
That is true, but the formula just says that no such observer
hovering over the horizon exists.
The claim means that the nearest place one can hover over a black
hole is the place where the downwards force is c^4/4G.
To find a counterexample, one would have to show that hovering nearer...
A new claim has appeared in physics. It is claimed that there is a largest
possible force, namely c^4/4G or 3 x 10^43 Newton.
(The claim is made in the paper http://xxx.lanl.gov/abs/physics/0309118 )
All my friends and acquantances have first said "wrong!"
but then failed to produce a...