June 7th, 2012, 08:29 AM
Some scientists believe that rotating objests experience friction
caused by physical vacuum:
Vacuum has friction after all - space - 11 February 2011 - New Scientist
Minds of people seems to be divided in this issue.Many disbelieve that such effect
exist.I think that if such effect really exist it may mean an almost inexhaustable energy
source.What do you think about it?
How about framedragging? every object has a mass so every object slightly distorts space. If an object is spinning realy fast, maybe the distortion of space will slow it down. Maybe the Casimir force will slow down the object as well
Surely it would mean exactly the opposite: yet another way in which energy is lost in a system. How can friction be a source of energy?Originally Posted by Stanley514
You can warm your hands up on a cold day with friction.
Rotating planets is not enough to you ?! Friction is able to produce heat.Heat is energy.They theorize that materials with special properties which absorb electromagnetic fields better exibit vacuum pressure better.Then we take material with excellent properties of this kind and bound it to the rotating Earth.Surely it would mean exactly the opposite: yet another way in which energy is lost in a system. How can friction be a source of energy?
Most heat is waste heat.
See this thread as a perfect ecample.
Stanley, Just imaginge the amount of enery it takes to drive planet earth. I don't care what anyone want to think, everything is possible and not possible. We cannot prove anything except in our selves. Once we can tap into the spiritual realm everything goes.
Mother/Father
Please keep such posts out of the Physics forum. It's for real science.
Just a friendly FYI for now.
What energy source?
Let's take the Earth. We know that it's rotational period increases by 2 milliseconds a century due to tidal interaction with the Moon. So let's be generous and say that 1/10 of that is due to this rotational friction. This means that the Earth slows by 0.0002 seconds in a century due to it. With the mass of the Earth, this works out to an energy difference of 1.2e21 joules or 3.33e14 kwh. This may seem like a lot, but remember, this is over a century, and the U.S. consumption of energy in just a year is 2.9e13 kwh. So to put it roughly, even if we are extremely generous with how much effect the friction has, and even if we could capture 100% of the energy, we would only get energy at 1/1000 the rate that the U.S. alone uses energy.
Or let's put it another way. The article says that the energy is radiated away by photons. If we take 1.2e21 joules divided by the number of seconds in a century, we get a radiating rate of 3.8e11 joules/sec or 3.8e11 watts. However, this is being radiated from the entire surface of the Earth, which is 5.1e14 m². This means we get 0.00074 watt/m² of Earth surface. You would need to collect the energy from a area ~1/3 km square to keep a single 100 watt bulb lit.
To Janus:
My bold idea is not to use natural friction of Earth in physical vacuum which might me practically
non-existent, but to create such friction artificially.If some rotating body exibits friction, the largest
heat creation will be in the points of friction.Therefore if you have some material which interacts
with physical vacuum very well and this material is bound to Earth it should create heat in point of
friction e.g. this material should get hot.Then you connect this material to a steam turbine and deal
is done.
June 8th, 2012, 03:18 AM
MeteorWayne , What is the problem? I am not sure which part of my statement I should keep out of the forum. What are you saying The spirit is not part of your make up? or dark energy is not a part of the sience you study. What is a vacuum? is it not a part of the whole? There are so many different angles to the study of any phenomena. Why do you believe that my post is different to yours? Is it not your spirit asking these questions about energy in a vacuum? I am sure you can appreciate that enery is every where also in a vacuum and at some point there will be friction if that is the only way of creating energy. Please explain to me what is false science as opposed to real science, and don't swallow the dictionary. How can you make statements about phenomena without intuition? Why don't you ask me what I meant rather than don't post such statements on the physics fourum. I thank you for the friendly advice but I think you should keep one sided ideas out of the fourum and allow new ideas to come forward. Am I breaking a rule?
Last edited by Mother/father; June 8th, 2012 at 03:25 AM. Reason: I used the wrong name
WTF is a physical vacuum?
An electrolux... Or maybe a Kirby? Actually I believe "Physical Vacuum" refers to physical presence of field energy and particulate
matter and how it could influence the topological properties of space time.
Unless it is refering to Vacuum State which is a whole other ball of quantum yarn.
trash can candidate!
You are still missing the point about how just weak this friction effect (if it even actually exists) would be.
It varies by the size of the object and how well it absorbs EM radiation. The example they give is a 100nm speck of graphite, which is small and absorbs light well.
It would take ten years for such a speck to lose 2/3 of its rotation speed.
So what happens if we scale this up to a hunk the size of the Earth? the Earth is 12756000 m across or 1.3e14 times that of the speck. The ability to absorb EM radiation increases with the surface area, which increases by the square of the increase in size. However, the volume, and thus the mass increases by the cube of the increase in size, this means that the mass increases 1.3e14 times faster than the surface area. This also means that it should take 1.3e14 time longer for the "friction" to slow the Earth sized hunk of graphite to 1/3 its original speed.
Assuming that the hunk starts with the same rotation rate of the Earth, this works out to 1.3e13 centuries to increase the day by 48 hrs. This works out to a rate of 3 nanoseconds per century, which is ~1/150,000 the rate at which the Earth loses rotation due to tidal interaction with the Moon( this is why I said that assuming 1/10 of this rate was being very generous.)
So to even get that 0.00074 watt/m² that I mentioned in my last post, (keeping in mind that the "heat" generated by this friction cannot exceed the rotational energy lost due to the friction) you would have to have a substance that absorbed em radiation many many times better than graphite. (not even reasonably possible, seeing as even something much more reflective than graphite, such as fresh concrete, absorbs ~45% of the light that falls on it).
And that is not even taking into account that the fact that we were considering a huge hunk of graphite, which has a much lower density than the Earth does. This means that it has less rotational energy than the Earth and loses less with the same amount of slowing.
The upshot is that this effect would be so small that no method that would make it a viable energy source.
Moderator Note: As Meteor has pointed out to you, this is a Science Forum. We disucss the findings of science and scientific methodology and we do so while broadly following that methodology. Statements such as the following are, by definition, unaccetable, since they do not follow scientific methodology, or even give an implicit nod to its importance.
everything is possible and not possible. We cannot prove anything except in our selves. Once we can tap into the spiritual realm everything goes.
Within the physics sub-forum and other science based sub-forums please follow those guidelines. Thank you.
Their theory doesn`t state that graphite is the best material which is able to absord EM radiation.The ability of material to absorb EM radiation doesn`t depend on surface area but also on properties of material itself.Also materials with high surface area could be created.I think all those calculations do not have sense unless effect itself would be practically proved.It varies by the size of the object and how well it absorbs EM radiation. The example they give is a 100nm speck of graphite, which is small and absorbs light well.
I'm sorry, but did you even read the whole post? Fresh concrete already absorbs 45% of the EM radiation that falls on it and that is far less than what graphite absorbs. The maximum that any substance could absorb is 100%. Ergo, the best you could ever hope for is an absorption rate of 2.22 times that of fresh concrete. Since graphite already absorbs more than fresh concrete does, the difference between graphite and the 100% absorber would be even less.
IOW, there is no substance that can even theoretically make this a viable source of energy production. It's like trying to use a drag chute as a brake in interstellar space. increasing the efficiency of the parachute will not make it an practical method of braking because even a 100% efficient parachute would not create enough drag.
Just give up on this idea already, it is a lost cause.
In the post they state that hot material will have vacuum friction drastically increased.
I do not think it is because it absorbs EM radiation better.Also it is not clear whether
friction could occur only as result of EM absorption.Posibly there is some other ways.
For example a charged material may create repulsion of virtual particles of the opposite
charges and thus friction.
[QUOTE=Stanley514;330925]In the post they state that hot material will have vacuum friction drastically increased.
I do not think it is because it absorbs EM radiation better.
[\quote]No, they say that in a hot environment the drag increases. This is because virtual particle creation increases, and there are more to be absorbed. But if the environment is hot, then it's getting energy from somewhere, and that's what you need to be looking at as an energy source. The energy needed to maintain the temperature is going to be magnitudes larger than any energy you'll get from the virtual particle friction. Put another way, it would take much more energy to keep the object hot than the friction drag makes.You are grasping at imaginary straws to keep afloat an idea that has already sunk. Nothing in the article even suggests that anything like that is the even a slight possibility. It talks about a particular effect, under particular conditions, due to particular causes based on theory. This doesn't leave the window open for other "possible" means for friction. You can't just say maybe this or maybe that. Wishful thinking is not science.
Also it is not clear whether
friction could occur only as result of EM absorption.Posibly there is some other ways.
For example a charged material may create repulsion of virtual particles of the opposite
charges and thus friction.
And with that, I'm done with this subject.
In my view,
vacuum is not supposed to have matter ( as you ALL must know) , <-------- (1)
matter collides with matter to create friction. <--------(2)
So taking (1) and (2) into consideration, vacuum exerts no friction on any object
Else you may find Moon drifting towards you ( Since it will lose its velocity, and according to Newton, it will come crashing into Earth
Note : Please do not post anything under this thread which is a correct reply to the thread
An electromagnetic field is a force. A vacuum posses such.
A force acts on a body, or a charge, or space/time?
What holds matter together?
Geo, I respect your views, but I believe we are talking about friction caused by a vacuum.
Do not forget that theories are models of reality.
Does vacuum have friction?
This is a good question, but in today's physics I think it is seldom addressed. Newton's first law of motion says "every object continues in its state of rest, or of uniform motion in a straight line, unless compelled to change that state by external forces acted upon it." Does this imply there is generally little or no friction when traveling through vacuous space? and is space vacuous?
Today the vacuum of space is called the Zero Point Field. We know that within interplanetary space, for instance, there is Zero-Point-Energy within it and particles such as a plethora of neutrinos, with a great number of electrons, some protons, and a sprinkling of anti-matter. So the greatest vacuum physically possible would seemingly have at least some friction to it. There are other possible theoretical particles such as dark matter, Higg's particles, gravitons, and a great many other theoretical possibilities of increased particulate friction.
A hypothetical entity having nothing at all within it, not even Zero Point Energy, would seemingly have the possibility of no friction concerning something traveling through it, but few believe there is such a thing.
Newton's first law would not be effected by such friction, however, since all such friction producing entities would be considered "external forces."
As to an infinite supply of energy: To produce energy one must transform a higher state of energy density to a lower energy density to extract some of the energy difference. The Zero Point Energy/ Field is theoretically, and by definition, the lowest possible energy state and therefore no excess energy can be extracted from it. This is the mainstream answer and mine too
Last edited by forrest noble; June 22nd, 2012 at 11:29 AM.
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