first off, Hi everyone, I finally decided to sign up here to ask a question that arose from a discussion I had with a friend.
It's purely a thought experiment, and I'm quite sure it can't work, but I can't seem to figure out why.
It has to be something really simple I'm missing, but what?
-----------
Suppose we have a teleporting device, that converts matter to energy and vice-versa. We take two of these devices, and place one in orbit and one on the ground.
We put a chain into the ground station, which is turned into energy which is send up to the orbit station, in light or microwave or whatever is handy.
In orbit, the end of the chain is converted in matter again, and lowered to the ground. Now, we have a chain that is constantly pulling down, with no counter-balance. Like an overbalanced wheel that actually works.
As a link rematerialises in orbit, all links drop down a bit, and the bottom link disappears into the ground teleporter, dematerialises and it send up to orbit, to drop down again.
As each link of the chains, it generates energy.
---------------------------
So, that's the idea. Now, before I lose my sanity, does anyone why this won't work?
If you are suggesting that the whole system produces more energy than it uses then no.
It takes more energy to get the "chain" into orbit, regardless of it's state, than it can produce as it falls down the gravity well.
It takes more energy to get the "chain" into orbit, regardless of it's state, than it can produce as it falls down the gravity well.
QUOTE (TomB+Jun 18 2008, 10:18 PM)
If you are suggesting that the whole system produces more energy than it uses then no.
It takes more energy to get the "chain" into orbit, regardless of it's state, than it can produce as it falls down the gravity well.
This is reminiscent of the "Woodward effect." Only he's trying to produce "propellantless propulsion."
It takes more energy to get the "chain" into orbit, regardless of it's state, than it can produce as it falls down the gravity well.
This is reminiscent of the "Woodward effect." Only he's trying to produce "propellantless propulsion."
QUOTE (Alcari+Jun 17 2008, 11:27 AM)
first off, Hi everyone, I finally decided to sign up here to ask a question that arose from a discussion I had with a friend.
It's purely a thought experiment, and I'm quite sure it can't work, but I can't seem to figure out why.
It has to be something really simple I'm missing, but what?
-----------
Suppose we have a teleporting device, that converts matter to energy and vice-versa. We take two of these devices, and place one in orbit and one on the ground.
We put a chain into the ground station, which is turned into energy which is send up to the orbit station, in light or microwave or whatever is handy.
In orbit, the end of the chain is converted in matter again, and lowered to the ground. Now, we have a chain that is constantly pulling down, with no counter-balance. Like an overbalanced wheel that actually works.
As a link rematerialises in orbit, all links drop down a bit, and the bottom link disappears into the ground teleporter, dematerialises and it send up to orbit, to drop down again.
As each link of the chains, it generates energy.
---------------------------
So, that's the idea. Now, before I lose my sanity, does anyone why this won't work?
Let's assume, for example, that you're turning each chain link into a packet of energy in the form of photons, and then at the other end the energy of that packet of photons is transformed back into a chain link when the orbital station is reached.
As the photons 'climb' out of the gravity well, they loose momentum (and therefore energy), because work must be done to over-come gravity.
That's where this idea falls over, it takes work to over come gravity, including for photons, meaning there's less 'energy' available for them at the top of the gravity well.
Eseentially, when dealt with from a newtonian perspective, if we were dealing with cannonballs, then the cannonballs would slow down as the force of gravity does work to overcome, and oppose the momentum of the cannonballs, thus transforming kinetic energy into potential energy.
When dealing with photons, it's a little more complicated, the force of gravity still does work to overcome the momentum of the photons, but rather then the photons slowing down, their wavelength changes.
to recap:
'Energy loss' still occurs because irrespective of if your dealing with packets of photons, or particles, work is done by gravity to oppose their momentum, so you need an external energy source to make up the deficit.
(more or less).
It's purely a thought experiment, and I'm quite sure it can't work, but I can't seem to figure out why.
It has to be something really simple I'm missing, but what?
-----------
Suppose we have a teleporting device, that converts matter to energy and vice-versa. We take two of these devices, and place one in orbit and one on the ground.
We put a chain into the ground station, which is turned into energy which is send up to the orbit station, in light or microwave or whatever is handy.
In orbit, the end of the chain is converted in matter again, and lowered to the ground. Now, we have a chain that is constantly pulling down, with no counter-balance. Like an overbalanced wheel that actually works.
As a link rematerialises in orbit, all links drop down a bit, and the bottom link disappears into the ground teleporter, dematerialises and it send up to orbit, to drop down again.
As each link of the chains, it generates energy.
---------------------------
So, that's the idea. Now, before I lose my sanity, does anyone why this won't work?
Let's assume, for example, that you're turning each chain link into a packet of energy in the form of photons, and then at the other end the energy of that packet of photons is transformed back into a chain link when the orbital station is reached.
As the photons 'climb' out of the gravity well, they loose momentum (and therefore energy), because work must be done to over-come gravity.
That's where this idea falls over, it takes work to over come gravity, including for photons, meaning there's less 'energy' available for them at the top of the gravity well.
Eseentially, when dealt with from a newtonian perspective, if we were dealing with cannonballs, then the cannonballs would slow down as the force of gravity does work to overcome, and oppose the momentum of the cannonballs, thus transforming kinetic energy into potential energy.
When dealing with photons, it's a little more complicated, the force of gravity still does work to overcome the momentum of the photons, but rather then the photons slowing down, their wavelength changes.
to recap:
'Energy loss' still occurs because irrespective of if your dealing with packets of photons, or particles, work is done by gravity to oppose their momentum, so you need an external energy source to make up the deficit.
(more or less).
QUOTE
'Energy loss' still occurs because irrespective of if your dealing with packets of photons, or particles, work is done by gravity to oppose their momentum, so you need an external energy source to make up the deficit.
D'oh, of course.
I was thinking "Well, a photon going up won't slow down, so it will have the same ammount of energy at the top". I forgot that, while the photons won't slow down, they will redshift a little, losing energy anyway.
Thanks for helping out, it was driving me insane.
QUOTE (Alcari+Jun 20 2008, 03:18 AM)
D'oh, of course.
I was thinking "Well, a photon going up won't slow down, so it will have the same ammount of energy at the top". I forgot that, while the photons won't slow down, they will redshift a little, losing energy anyway.
Thanks for helping out, it was driving me insane.
You're welcome.
I was thinking "Well, a photon going up won't slow down, so it will have the same ammount of energy at the top". I forgot that, while the photons won't slow down, they will redshift a little, losing energy anyway.
Thanks for helping out, it was driving me insane.
You're welcome.
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