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  4. What effect does mass-energy density have on gravitational field strength?
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What effect does mass-energy density have on gravitational field strength?

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Offline jeffreyH (OP)

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Re: What effect does mass-energy density have on gravitational field strength?
« Reply #60 on: 10/10/2013 00:59:07 »
Quote from: yor_on on 09/10/2013 23:54:16
Mostly transformed into heat, as I understands it, the 'thing' missing from your muscles etc, costing 'energy' for you. But if you mean that there seems to be something weird about the concept that everything just transforms, and nothing ever is lost, the universe being in a equilibrium I agree :) Just turn it around and ask yourself why accelerations and life exist, if there just is a equilibrium? Doesn't mean it has to be wrong though, but there is some aspect missing to it. The one explaining why accelerations and life exist.

Acceleration is one of the things Einstein should have concentrated on a bit more. Dimension and momentum have a relationship that brings into play a weird effect regarding density. I have only just started putting this together. If I start discussing too much of it now it will only cause a lively debate without the mathematics in place to back it up.
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Offline webplodder

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Re: What effect does mass-energy density have on gravitational field strength?
« Reply #61 on: 10/10/2013 10:17:35 »
Quote from: webplodder on 09/10/2013 17:23:45
If I throw a ball, presumably the mass of the ball will increase since I have imparted some kinetic energy to it but would I lose energy? My arm would be travelling at the same speed as the ball before I let it go so the ball and arm would experience the same kinetic energy. However, I must have used up some energy in the process of throwing the ball so what is the net result of all this?

Quote from: yor_on on 09/10/2013 23:54:16
Mostly transformed into heat, as I understands it, the 'thing' missing from your muscles etc, costing 'energy' for you. But if you mean that there seems to be something weird about the concept that everything just transforms, and nothing ever is lost, the universe being in a equilibrium I agree :) Just turn it around and ask yourself why accelerations and life exist, if there just is a equilibrium? Doesn't mean it has to be wrong though, but there is some aspect missing to it. The one explaining why accelerations and life exist.

Ok, I see. So, most of the energy used in throwing the ball would be expended as heat although a tiny amount of mass in my arm would be increased due to acceleration.
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Re: What effect does mass-energy density have on gravitational field strength?
« Reply #62 on: 10/10/2013 11:06:51 »
Quote from: jeffreyH
If you do not believe this is a distance ...
It's a given that nobody believes that's distance, not just Supercryptid. c is, by definition the speed of light and thus a speed which is distance/time it's given that tis is not distance. But you know that already, right. Since you surely know that this is different than distance what exactly are you trying to imply here?
« Last Edit: 10/10/2013 11:09:31 by Pmb »
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Offline jeffreyH (OP)

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Re: What effect does mass-energy density have on gravitational field strength?
« Reply #63 on: 10/10/2013 12:23:58 »
Quote from: Pmb on 10/10/2013 11:06:51
Quote from: jeffreyH
If you do not believe this is a distance ...
It's a given that nobody believes that's distance, not just Supercryptid. c is, by definition the speed of light and thus a speed which is distance/time it's given that tis is not distance. But you know that already, right. Since you surely know that this is different than distance what exactly are you trying to imply here?

There is a time element to energy, kilowatt hours being an example, because that is the most sensible way to view it as energy and momentum are linked. This is not the actual momentum but the amount in that time. The speed component of c translates into amount of energy per second squared with no implicit momentum. I know what I mean but sometimes explain it in a bad way.
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Re: What effect does mass-energy density have on gravitational field strength?
« Reply #64 on: 10/10/2013 16:40:43 »
Quote from: jeffreyH
There is a time element to energy, kilowatt hours being an example, because that is the most sensible way to view it as energy and momentum are linked.
That's incorrect. It's wrong to say that there is a time element to energy because time is related to power by P = E/t. This is like saying that a spatial location has a time element because v = S/t 

You need to rethink your response.
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Offline jeffreyH (OP)

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Re: What effect does mass-energy density have on gravitational field strength?
« Reply #65 on: 10/10/2013 17:39:38 »
Quote from: Pmb on 10/10/2013 16:40:43
Quote from: jeffreyH
There is a time element to energy, kilowatt hours being an example, because that is the most sensible way to view it as energy and momentum are linked.
That's incorrect. It's wrong to say that there is a time element to energy because time is related to power by P = E/t. This is like saying that a spatial location has a time element because v = S/t 

You need to rethink your response.

But also E=Pt where multiplying by a time element gives energy. So power is energy over time. The time is implicit.
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Re: What effect does mass-energy density have on gravitational field strength?
« Reply #66 on: 10/10/2013 22:18:19 »
Time may be implicit in power, but it isn't in energy. Power and energy are two different concepts. E=mc2 deals with energy, not power.
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Re: What effect does mass-energy density have on gravitational field strength?
« Reply #67 on: 11/10/2013 00:48:28 »
Quote from: jeffreyH on 10/10/2013 17:39:38
Quote from: Pmb on 10/10/2013 16:40:43
Quote from: jeffreyH
There is a time element to energy, kilowatt hours being an example, because that is the most sensible way to view it as energy and momentum are linked.
That's incorrect. It's wrong to say that there is a time element to energy because time is related to power by P = E/t. This is like saying that a spatial location has a time element because v = S/t 

You need to rethink your response.

But also E=Pt where multiplying by a time element gives energy. So power is energy over time. The time is implicit.
You're twisting things to meet what you'd like to see written. That's bad science.
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Offline jeffreyH (OP)

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Re: What effect does mass-energy density have on gravitational field strength?
« Reply #68 on: 11/10/2013 01:36:46 »
Quote from: Pmb on 11/10/2013 00:48:28
Quote from: jeffreyH on 10/10/2013 17:39:38
Quote from: Pmb on 10/10/2013 16:40:43
Quote from: jeffreyH
There is a time element to energy, kilowatt hours being an example, because that is the most sensible way to view it as energy and momentum are linked.
That's incorrect. It's wrong to say that there is a time element to energy because time is related to power by P = E/t. This is like saying that a spatial location has a time element because v = S/t 

You need to rethink your response.

But also E=Pt where multiplying by a time element gives energy. So power is energy over time. The time is implicit.
You're twisting things to meet what you'd like to see written. That's bad science.

OK. Bear with me a while. Humour me in other words.
Firstly c is distance travelled over time taken. So yes in respect to light that is a speed. Can we agree on that first? Then I will proceed to the next step in my thinking.
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Re: What effect does mass-energy density have on gravitational field strength?
« Reply #69 on: 11/10/2013 04:19:19 »
Quote from: jeffreyH
OK. Bear with me a while. Humour me in other words.
Firstly c is distance travelled over time taken.
Yes. That is correct.

Quote from: jeffreyH
So yes in respect to light that is a speed. Can we agree on that first? Then I will proceed to the next step in my thinking.
And I will do the same in my thinking as well. Space and time are primative quantities. That means that they are not defined in terms of other quantities. Defined terms such as speed v = distance/time are defined in terms of other quantities.

Words such as "element" as in "There is a time element to energy, .." are not defined in physics. However without such a definition we use the one found in a dictionary

See http://www.merriam-webster.com/dictionary/element

However your use is far from clear as it can be found in a dictionary. Otherwise when you start solving for variables in equations and saying "There is an x element to this physics because x is in the equation" isn't a very useful notion.

It'd be far better if you clearly stated what you mean by ""element".
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Offline jeffreyH (OP)

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Re: What effect does mass-energy density have on gravitational field strength?
« Reply #70 on: 11/10/2013 12:23:26 »
Quote from: Pmb on 11/10/2013 04:19:19
Quote from: jeffreyH
OK. Bear with me a while. Humour me in other words.
Firstly c is distance travelled over time taken.
Yes. That is correct.

Quote from: jeffreyH
So yes in respect to light that is a speed. Can we agree on that first? Then I will proceed to the next step in my thinking.
And I will do the same in my thinking as well. Space and time are primative quantities. That means that they are not defined in terms of other quantities. Defined terms such as speed v = distance/time are defined in terms of other quantities.

Words such as "element" as in "There is a time element to energy, .." are not defined in physics. However without such a definition we use the one found in a dictionary

See http://www.merriam-webster.com/dictionary/element

However your use is far from clear as it can be found in a dictionary. Otherwise when you start solving for variables in equations and saying "There is an x element to this physics because x is in the equation" isn't a very useful notion.

It'd be far better if you clearly stated what you mean by ""element".

Let's ditch the element issue for now. Einstein came to the conclusion that there was a link between inertia and energy. Inertia is applicable in two situations. when a mass it at rest or moving at a constant velocity as long as no external forces are applied. Acceleration, deceleration and change of direction are the external forces. This is the next issue to agree upon.
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Re: What effect does mass-energy density have on gravitational field strength?
« Reply #71 on: 11/10/2013 12:59:23 »
Quote from: jeffreyH
Einstein came to the conclusion that there was a link between inertia and energy. Inertia is applicable in two situations. when a mass it at rest or moving at a constant velocity as long as no external forces are applied. Acceleration, deceleration and change of direction are the external forces. This is the next issue to agree upon.
The essence of his derivation is found in my website here
http://home.comcast.net/~peter.m.brown/sr/mass_energy_equiv.htm
Take a look at it and let me know what you think.
[/quote]
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Offline jeffreyH (OP)

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Re: What effect does mass-energy density have on gravitational field strength?
« Reply #72 on: 13/10/2013 01:19:01 »
Quote from: Pmb on 11/10/2013 12:59:23
Quote from: jeffreyH
Einstein came to the conclusion that there was a link between inertia and energy. Inertia is applicable in two situations. when a mass it at rest or moving at a constant velocity as long as no external forces are applied. Acceleration, deceleration and change of direction are the external forces. This is the next issue to agree upon.
The essence of his derivation is found in my website here
http://home.comcast.net/~peter.m.brown/sr/mass_energy_equiv.htm
Take a look at it and let me know what you think.

Very interesting. The energy-momentum relation is not what I am investigating. It is the simplified e=mc^2. I will post some more points when I get some time to put a document together. One thing to ponder. Is the Planck scale invariant with regard to the distortion of spacetime? The answer to this has a great bearing on how the search for a workable theory of quantum gravity.
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Re: What effect does mass-energy density have on gravitational field strength?
« Reply #73 on: 13/10/2013 08:25:36 »
Quote from: jeffreyH
The energy-momentum relation is not what I am investigating.
Sorry, but I don't see your point. I never mentioned that.

Quote from: jeffreyH
It is the simplified e=mc^2.
Huh? What does that mean? I.e. what is the simplified e=mc^2? Do you believe that there is there a non-simplified e=mc^2?

Quote from: jeffreyH
One thing to ponder. Is the Planck scale invariant with regard to the distortion of spacetime?
Yes. I believe so.
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Re: What effect does mass-energy density have on gravitational field strength?
« Reply #74 on: 13/10/2013 10:52:41 »
Quote from: Pmb on 13/10/2013 08:25:36
Quote from: jeffreyH
The energy-momentum relation is not what I am investigating.
Sorry, but I don't see your point. I never mentioned that.

Quote from: jeffreyH
It is the simplified e=mc^2.
Huh? What does that mean? I.e. what is the simplified e=mc^2? Do you believe that there is there a non-simplified e=mc^2?

Quote from: jeffreyH
One thing to ponder. Is the Planck scale invariant with regard to the distortion of spacetime?
Yes. I believe so.

Not E^2=(pc)^2+(m0c^2)^2.
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Offline yor_on

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Re: What effect does mass-energy density have on gravitational field strength?
« Reply #75 on: 14/10/2013 17:25:47 »
at webplodder: Your relative mass should increase I guess, as you accelerate your arm, as well as the balls mass should, but as soon as you both are uniformly moving, it must be gone:) Interesting idea, better check it with Pete though.
=

That's wrong, your relative mass will still be there, in a uniform motion as well as in a acceleration. What I was thinking of was inertia there, not relative mass. That is what will be gone in after you finished accelerating. That relative mass you have will be expressed as kinetic energy in a collision. And there your speed will matter, acceleration or no acceleration. The inertia is still existent in a uniform motion though, although unmeasurable for you. and the inertia accelerating, can in a uniformly constant acceleration (at one gravity), translate into the same gravity we meet on Earth. Maybe it's more correct to call it your arm feeling gravity :) accelerating? This is definitely Pete:s field of interest.

Hmm rereading it again: I must have meant that as soon as your arm stops moving it also has decelerated to the same speed it had before starting to throw a ball for example. And in so motto it is correct.
« Last Edit: 21/11/2013 17:32:04 by yor_on »
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Offline jeffreyH (OP)

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Re: What effect does mass-energy density have on gravitational field strength?
« Reply #76 on: 16/10/2013 21:42:48 »
Quote from: Pete on 13/10/2013 08:25:36
Quote from: jeffreyH
The energy-momentum relation is not what I am investigating.
Sorry, but I don't see your point. I never mentioned that.

Quote from: jeffreyH
It is the simplified e=mc^2.
Huh? What does that mean? I.e. what is the simplified e=mc^2? Do you believe that there is there a non-simplified e=mc^2?

Quote from: jeffreyH
One thing to ponder. Is the Planck scale invariant with regard to the distortion of spacetime?
Yes. I believe so.

On the Planck scale issue, if the universe were measured out into Planck cubes and the cubes that were being traveled through by mass undergoing acceleration, would a length contraction be observed at that scale? On a macroscopic scale an observer external to the accelerating system would see length contraction. How can this be separated from the finer grained resolution?

What if contraction itself and the inherent momentum of the scaling factor produced the gravitational effect WITHOUT any elementary particle. Maybe we are looking for a graviton that doesn't exists. That might be the reason for all the failure. If momentum and mass-energy density are interlinked some strange effects may become apparent.
« Last Edit: 16/10/2013 21:47:20 by jeffreyH »
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Re: What effect does mass-energy density have on gravitational field strength?
« Reply #77 on: 17/10/2013 15:26:43 »
Quote from: jeffreyH
On the Planck scale issue, ...
The Planck scale comes from quantum gravity. Since I don't know quantum gravity you're going to find me very silent on questions about the "Planck scale issue" including your questions here. Sorry. I just don't think it's wise to talk about physics I'm not familiar with. I wish more people felt that way.
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Re: What effect does mass-energy density have on gravitational field strength?
« Reply #78 on: 20/10/2013 17:18:37 »
One thing that never gets mentioned with respect to gravitational issues is parallax. We take it for granted but there are issues to do with this effect on a local scale.
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Re: What effect does mass-energy density have on gravitational field strength?
« Reply #79 on: 21/10/2013 07:42:52 »
Quote from: jeffreyH
One thing that never gets mentioned with respect to gravitational issues is parallax.
That's because there's no reason why it should. It has absolutely nothing to do with gravity. It only pertains to optical observation of celestial bodies. Why do you think it should have anything to do with gravity at all?

Quote from: jeffreyH
We take it for granted but there are issues to do with this effect on a local scale.
When making assertions like this its helpful to back it up with facts. E.g. what are these issues that you're referring to?
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