So in isolated systems energy is lost as heat, and entropy increases. Entropy of an isolated system never lowers its entropy.
Gravity never zero
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So in isolated systems energy is lost as heat, and entropy increases. Entropy of an isolated system never lowers its entropy.
I never said , dF = F1 - F2 = -dx .
I only said dF = F1 - F2 .
How can you assume dF = -dx ... or ... F1 - F2 = -dx ?
My logic is simple . I considered the principle of 'conservation-of-energy' .
When the momentum of the mass causes frame-dragging ; a physical space-shift occurs . This occurance is confirmed by bending of a ray-of-light around a moving mass of very high momentum . For this physical space-shift to occur , some amount of energy is required . What is the source of this energy ? ... The only source is the kinetic energy of the mass . So, at the occurance of frame-dragging ; there will be a transfer of energy from the mass to the space and the space will be dragged along with the mass .
Thus kinetic energy of the mass will be reduced . Its effective velocity will be reduced . So, it will travel less distance than the distance travelled ; had there been no frame dragging . This difference in distance , i put it as 'dx' and calculated the force for frame-dragging accordingly .
At lower momentum , there will be no transfer of energy from the mass to the space . So there will be no frame-dragging and Newton's 1st Law of Motion on inertia will hold true .
You are right, I was hasty there. But wouldn't it be something more like,
$$F_1 - F_2 = \frac{Gm_1m_2}{-(dx)^2}$$
This is probably even wrong, but what I was trying to get at is two things, $$F_x$$ is defined by an inverse square relationship between mass and distance and you cannot just drop the minus sign when subtracting F2 from F1, when F2 > F1.
But none of this has anything to do with frame-dragging, you are just playing with a difference in gravitational potential between two locations.
Edit: Even that is restricted to the perspective of Newtonian Mechanics or GR in a locally flat space and weak gravitational field potential.
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These statements idicate that you do not understand what entropy is. I will try to find the time to write up a 'primer' on entropy in a relatively non-technical way. You are not the only one who does not understand entropy and I think it would be very helpful, the concept can be rather confusing.
Entropy
The energy we see coming from distant galaxies, directly and indurectly generated by gravity is red shifted. The difference in the energy (original -red shifted) is a measure of the entropy going into the universe. The red shift also reflects a loss in the original energy information generated by the galaxies. This loss in emitted energy is attributed to space-time expansion or the expansion of the universe is an expression of entropy.
This is easy, so what is the problem?
The energy we see coming from distant galaxies, directly and indurectly generated by gravity is red shifted. The difference in the energy (original -red shifted) is a measure of the entropy going into the universe. The red shift also reflects a loss in the original energy information generated by the galaxies. This loss in emitted energy is attributed to space-time expansion or the expansion of the universe is an expression of entropy.
This is easy, so what is the problem?
The problem is that entropy is not an 'expression' of the expansion of the universe.
Your other misconcesptions were spelled out in the previous post.
When the concept of entropy was formulated the idea the Universe was expanding wasn't around.
Enthropy and the Expanding Universe almost certainly have a relationship.. The usable energy in the Universe will be reduced the more the Universe expands. That would seem to be a natural consequence of expansion.
Correct.
Enthropy and the Expanding Universe almost certainly have a relationship.. The usable energy in the Universe will be reduced the more the Universe expands. That would seem to be a natural consequence of expansion.
Agreed. The expansion of the universe implies that the final state of the universe will approach absolute zero resulting in maximum entropy state. But Wellwisher thinks the expansion IS entropy - which makes no sense. He also thinks that entropy is dark energy -which makes no sense. He also thinks that the waste heat of entropy must be attenuated by another mass which is wrong. He also thinks entropy implies that evolution can't occurr, which is goofy.
I'm pleased that you agreed with me, for I was worried I might get a warning for saying something unscientific!
Nothing is Dark Energy, for I'm skeptical that it even exists. "Attenuated" gee I don't even know what that means. Is it like "absorbed".... heat absorbed by other matter? If it is it could easily happen.
Measurements indicate that the expansion of the universe is speeding up. That acceleration would take energy. We don't know what that energy could be - hence the name 'dark energy'. What is this energy?:shrug:
"Attenuated" gee I don't even know what that means. Is it like "absorbed".... heat absorbed by other matter? If it is it could easily happen.
Attenuated means more or less absorbed - it is a term from my 'radiation control' days and it is generally used when talking about radiation. Photons are attenuated (or absorbed) by charged particles, usually electrons.
Consider m1 and m2 are masses of two astronomical bodies in the space at some distance , where m1 > m2 .
So, m2 will move towards m1 ; due to attractive force from m1 .
As m2 moves closer to m1 , its attractive force will rise ; so its velocity and momentum will also rise .
Say , at a distance 'y' from m1 and time 't' ; momemtum of m2 causes frame-dragging . So, its velocity will be reduced due to frame-dragging efect . For a duration of time 'dt' , it will travel some distance less than had there been no frame-dragging . Consider this difference in distance as 'dx' .
At time 't+dt' , m2 will be at some distance from m1 .
Had there been no frame-dragging , at time 't+dt' , the distance between m1 and m2 would have been different . Consider this distance as 'x' .
So, with frame-dragging effect at time 't+dt' , the distance between m1 and m2 will be 'x+dx' .
F1 is force at distance x and F2 is force at distance x+dx .
So, F1 > F2 .
This difference between F1 and F2 , can be considered as force generated due to the effect of frame-dragging at time 't+dt' .
You are essentially equating frame-dragging with an inertial like interaction between space and matter, with an assumption of, "for every action there is a reaction", where if the momentum of an object drags on space, space must resist that action. In another thread somewhere I suggested that logic implied the same thing. What is missing is that "that" interaction would be trivially insignificant at anything other than relativistic velocities, accelerations or in the presence and close proximity of massive gravitational fields.
Which means it can only be even imagined from a context of Einstien's world view and GR. There is nothing within the scope, context and/or limitations of Newtonian Mechanics.., even much of the flat spacetime of special relativity, where frame-dragging would play any similar detectable role.
In practice we are limited by both time and velocities that define the scope of our experience, to one that lies outside such interactions. We may theorize circumstances beyond our experience that involve such and one day some bright young mind may even devise some test, of what we have imagined.., but this lies outside the reach of practical experience and far beyond the limitations of the math here presented.
Such an effect or interaction (if it exists), within the context of our limited experience (time and velocities), is essentially zero and cannot be explained or even imagined within the limitations of the math you are using.
There is some logic to the basic concept. The approach to the math you are applying is entirely insufficient to the task of describing such an interaction between mass and space. As JamesR said earlier, this lies in the realm of GR not Newtonian Mechanics. I add that in practice it even stretches the limits of SR and the locally flat spacetime that it is confined to.
You are right. It is the other way around. The expansion of the universe is an expression of universal entropy needed to satisfy the second law. The expansion of space-time, by speeding up time, allows all processes to express entropy at a faster rate, to keep up with the energy output that results from the lowering of entropy due to gravity. If we double time we can make twice as many defects compared to single time. This is needed because entropy startsto fall behind due to gravity.
The universe moves in the direction of higher entropy. If we had a star and could make gravity equal to zero, hypothetically, the matrerial of the star would move in the direction of higher entropy (all force gone). This means spreading out and random diffusion. Since that is the direction of higher entropy, if we add gravity and reverse this, we move toward lower entropy. Gravity applies work, which is force over distance to lower entropy. There is some entropy created via this work. There is also a lot of energy given off into space that has no matter for the total entropy requirement of the second law.
This energy goes into essentially empty space and can not increase entropy at the rate, entropy is falling due to gravitational work. I suppose the Compton effect, by increasing the entropy if electrons would accout for qite a bit of this, but since that has been put aside, in favor of the more spectacular doppler shift, expansion is where the entropy gain can occur.
The need for dark matter and energy come down to GR not allowing one to do a good energy/entropy balance generared by newtonian gravity
What Energy could be "Dark Energy" (DE)? When I first heard of DE I thought "oh good, they will finally find that matter (m= E/(C^2)) and energy (E = 1/2mv^2, velocity^2) are continually interchanging".
So I tended to think of the DE being contained within the matter that is accelerating. Matter unravels back to the energy it was formed from, and the only way to conserve the energy is for it to accelerate in the direction it is going.
Note: this is a personal thought - like a placeholder till science proves what DE is.)
What you need to do, Origin, is give us the definition you are using for entropy, and then do an entropy balance for the universe, to show you understand what entropy is. The politics of negativity without backing up the criticismmay work on those who can't think for themselves. But for those who like to think, an entropy balance for the universe would strengthen your argument, if you think it exists.
Entropy (S) needs energy for it to increase, at any given temperature. Entropy is a form of energy divided by temperature. The red shift tells us that only a fraction of the energy produced in the universe being lost to entropy. The rest goes into the work needed to expand the universe.
With machines we put energy in and get work out. The efficiency of this machine reflects the lost energy going into entropy. If the machine is 80% efficient only 20% of my energy goes into entropy. The 80% goes into useful work.
If took a crane and lift a large weight above the earth, this will require work. The expansion of the universe also requires work to resist gravity.
Entropy (S) needs energy for it to increase, at any given temperature. Entropy is a form of energy divided by temperature. The red shift tells us that only a fraction of the energy produced in the universe being lost to entropy. The rest goes into the work needed to expand the universe.
With machines we put energy in and get work out. The efficiency of this machine reflects the lost energy going into entropy. If the machine is 80% efficient only 20% of my energy goes into entropy. The 80% goes into useful work.
If took a crane and lift a large weight above the earth, this will require work. The expansion of the universe also requires work to resist gravity.
When I get a chance I will try to explain it to you but it will clearly need to be rather detailed yet easy for non-thermodynaics educated person to understand and I don't have time right now.
If that was the case wouldn't matter dominate the universe as the DE is used up doing all this work? For whatever the work is done on that will become more massive intensifying the gravity and hence requiring more work to keep expanding etc till the Universe collapses into the Big Crunch.
I think that definition is too vague, and so does this guy:wellwisher said:
http://www.thp.uni-koeln.de/~szendro/WS10/machta.pdfJ. Machta Department of Physics and Astronomy said:
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