The pressure profile in a long outgassing vacuum tube

The Demon in a Vacuum Tube

In the present paper, several issues concerning the second law of thermodynamics, Maxwell’s demon and Landauer’s principle are dealt with. I argue that if the demon and the system on which it operates without dissipation of external energy are made of atoms and molecules (gas, liquid or solid) in thermal equilibrium (whose behaviour is described by a canonical distribution), then the unavoidabl...

Vacuum Tube Amplification

Designing Vacuum Tube Circuits

A vacuum tube based improved solar cooker

A new type of improved solar cooker based upon the use of a single vacuum tube is presented in this paper. The proposed cooker utilizes a solar collector consisting of parallel plane rectangular glass mirror strips mounted inside a wooden frame and requiring one dimensional solar tracking through a common driver. The proposed design can be either installed over the roof top of a house or near a...

Are There Pressure Waves in the Vacuum?

Are there sound waves in the vacuum? The question might seem silly, but here’s my point: (i) the Higgs vacuum of the Standard Model, with its nonzero background field 〈Φ〉 6 = 0, is not ‘empty,’ but rather is a kind of medium. (ii) For very basic reasons, one expects any medium to propagate pressure waves for sufficiently long wavelengths. At length scales much, much longer than the mean free pa...