Why do you think no current can flow? Have a look at these two documents:

http://www.cmmp.ucl.ac.uk/~nts/teach...noise_0405.pdf
http://www.physics.utoronto.ca/under...rmal-Noise.pdf

Both of them talk about the noise filtering effect of a capacitor in parallel with the resistor. Filtering can't occur unless current flows in the capacitor.

Now, I know you can't believe everything you read, but this is stuff being taught in universities, so I hope it's correct.

 

I thinks what we're trying to figure out is what prevents someone from extracting power from the noise signal. What allows a circuit to detect and amplify the noise signal but prevents it from rectifying the noise and producing energy for free?

 

Keeping in mind that perpetual motion and free energy machines can be patented regardless of their feasibility, below is an excerpt from a document entitled Zero-Point Energy Extraction Feasibility:
Would it work? The patent is almost 30 years old, and has expired, but then maybe the technology hasn't caught up yet. I am no expert on thermal noise or "free" energy, but this scheme seems to purport to take energy from ambient heat similar to the way photodiodes take energy from ambient light. Could a diode ever be made that would efficiently rectify nanovolts, or even microvolts? I don't have the guts to say it's impossible, but it certainly seems pretty far-fetched. I haven't read the patent, so I may be way off base.
There is a "free energy" site that mentions this patent, but some of their other projects are such blatant perpetual motion machines that I hesitated to mention it.

 

Yes exactly, what mechanism is responsible for this apparent truth.

But..
I do not think this is a free energy problem.

A resistor contains thermal energy at the every least that somehow can turn on an amplifier with noise power but this power cannot seemingly be delivered otherwise.

Let me site something:

"In every conductor or resistor at a temperature above absolute zero, the electrons are in random motion, and this vibration is dependent on temperature. Since each electron carries a charge if 1.602E-19 C, there are many little current surges as electrons randomly move about in the material. Although the AVERAGE current in the conductor resulting from these movements is zero, instantaneously there is a current fluctation that gives rise to a voltage across the terminals of the conductor."

- C.D. Motchenbacher, Low-Noise Electronic Systems Design.

So from this I gather, a large valued resistor(high thermal noise) connected to the input of an amplifier (with no other input power source) can infact bias the amplifier input on an instantaneous basis where an instantaneous time varying current will flow characterized by the noise power but the average current will be perfectly zero.

Does this sound right?

 

Thanks, one of these talks about an equipartion theorem from thermodynamics (which I unfamiliar with!) and has to do with the thermal equilibrium of the conductors in question and their noise power.

While I can't quantitatively show it, I think that noise power cannot deliver REAL power in conductors in thermal equilibrium because, the noise power itself exists as a fixed quantity due only to the material and temperature.

So if one conductor were to actually deliver real power to another, the effect would be a resistive heating and that loads' temperature would try to increase (RMS heating) but that cant happen if the two are in equilibrium.
They would just transfer noise power back and forth.