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21
Perhaps I could back that up with a simplified version? Parakorn, have a look at the depiction of gravitational potential:



The curvature you can see in the depiction relates to the Riemann curvature tensor. But things don't actually fall down because of this. The force of gravity is denoted by the degree of slope, the first derivative of potential. The tidal force or Riemann curvature tensor is denoted by the change in slope, the second derivative of potential.   
22
So no, I don't think it should matter if you moved the plates? If it's looked at as a field (virtual photons/waves) the inside of those plates should become a sort of cavity, that the field must adapt to, I think?


Well, but any adaptation must happen over time and cant be instantaneous, can it?
23
Quote
The water itself does not leave the used fuel pool.

The author left off the implicit "...we hope!".
24
Quote from: parakorn
   OK may be I didn't understand your paper or I didn't read your article clearly.May be you can to simplify about the different between Einstein General Relativity and Modern General Relativity in the easy word for me. Sorry for I didn't read your article clearly and sorry if this reply disturb you.  Thank you
Okay. Thanks. And I'd like to compliment you on being able to notice that you might have made a mistake and then be able to correct it and then move on. That's one of the cherished traits in physics that I admire in a person who's discussing physics. :)

Einstein defined gravity such that it's locally equivalent to an accelerating frame of reference. The weak equivalence principle states that at uniform gravitational field is equivalent to a uniformly accelerating frame of reference.

If you're in a flat spacetime then, regardless of what frame of reference (system of coordinates) you're using the Riemann tensor will be zero. There is no gravitational field in this frame. Now transform to a uniformly accelerating frame of reference. In that frame there is a uniform gravitational field. If you read page 9 in my paper you'll see this
Quote
In the year following the completion and publication of the general theory of relativity Einstein published the review article The Foundation of the General Theory of Relativity in 1916. The statement

"It will be seen from these reflections that in pursuing the general theory of relativity we shall be led to a theory of gravitation, since we are able to “produce” a gravitational field merely by changing the system of coordinates."
Others didn't like this notion since it seemed too odd for people to grasp. I.e. How can you create a gravitational field merely by changing to an accelerating frame of reference.  Since they knew that there's no kind of accelerating frame of reference that will mimic tidal gradients (which is dictated by spacetime curvature) they decided to think of a "real" gravitational field as being determined the presence of spacetime curvature. However that has a lot of problems because even some experts will claim that the gravitational force is replaced by spacetime curvature since one has nothing to do with the other in some instances, e.g. like the uniform gravitational field. I've seen most people not understand that a uniform gravitational field has no spacetime curvature because they think of gravity as being spacetime curvature and where ever there's a gravitational force there's spacetime curvature, which is wrong. I saw a guy publish a paper in the American Journal of Physics claim that a uniform gravitational field (which is flat - by definition) claim to have proved that it's curved. He made an error in his assumption of what the proper acceleration should be of a particle. Since he got a curved spacetime it should have told him that it was the wrong answer but since he assumed that gravitational fields have spacetime curvature then he made no mistake. See how these problems can arise because of not using Einstein's definition? His definition is how we think of gravity.

Einstein didn't like all that stuff about curvature. That's why he wrote that letter to Max Von Laue saying
Quote
... what characterizes the existence of a gravitational field from the empirical standpoint is the non-vanishing of the components of the affine connection], not the vanishing of the [components of the Riemann tensor]. If one does
not think in such intuitive (anschaulich) ways, one cannot grasp why something like curvature should have anything at all to do with gravitation. In any case, no rational person would have hit upon anything otherwise. The key to the understanding of the equality of gravitational mass and inertial mass would have been missing.

Make sense now? :)
25
Technology / Re: How can I make a whirlpool in a swimming pool?
« Last post by JohnDuffield on 01/09/2014 15:59:49 »
You make a Falaco soliton. It's a U-tube vortex. Unlike a bathplug vortex, there is no "sink" wherein water is draining away. It's just going round and round, something like the bottom half of a smoke ring. How do you make one? Simple. You get a plate, dip it into the water, then stroke it slowly forward whilst lifting it clear. See http://arxiv.org/abs/gr-qc/0101098 along with https://www.youtube.com/watch?v=PyjwZ39EDmw



Also have a look at On Vortex Particles by David St John. Sorry, the link doesn't work at the moment. 
26
   OK may be I didn't understand your paper or I didn't read your article clearly.May be you can to simplify about the different between Einstein General Relativity and Modern General Relativity in the easy word for me. Sorry for I didn't read your article clearly and sorry if this reply disturb you.  Thank you
27
Quote from: alancalverd
Spent fuel isn't much of a scientific problem as it is concentrated and concentrateable:
That's not what they do with it though. See
http://www.nei.org/Issues-Policy/Nuclear-Waste-Management
Quote
Most used fuel from nuclear power plants is stored in steel-lined concrete pools filled with water, or in airtight steel or concrete-and-steel containers.

What I don't get is why not fusion other than the notion "it works, don't fix it" which in this case I don't think that motto applies. All the problems with storage are nowhere as severe as they are with fusion waste. The products of fusion is helium as you know. Fill children's balloons with it, as they say. :)

http://www.nei.org/Issues-Policy/Nuclear-Waste-Management/Used-Nuclear-Fuel-Storage
Quote
Used nuclear fuel is in storage at the nation’s nuclear energy facilities. Most plants store used fuel in steel-lined, concrete pools filled with water, which acts as a natural barrier for radiation. The water also keeps the fuel cool while radiation decays. The water itself does not leave the used fuel pool.
28
New Theories / Re: Post Orgasmic Illness Syndrome (POIS)
« Last post by johanstefansson on 01/09/2014 11:08:16 »
Concretely: I can feel the microadenoma that is a kyst of 3 mm with palpation at the left testicule. For me it is only one side but there is a risk that microadenomas are on both sides. An echoghrapy will confirm the diagnosis, and after I will take an appointement in surgery, the operation is of a small importance (I'm not there, but I so hope I'm not wrong). I will write soon to confirm the results.

A nurse with POIS is exactly what we need. I pray for your success!
29
New Theories / Re: Post Orgasmic Illness Syndrome (POIS)
« Last post by johanstefansson on 01/09/2014 10:53:07 »
LAPOISSE2 - if I were to try your method of letting go within some months i would loose my family, reputation and income and wealth. I seriously don't recommend anyone to have unlimited orgasms.

Until some years ago when i discovered POIS i did let go and it was terrible.
30
Pete: take a look a Kirk Thorensen talking about thorium here.
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