The vacuum can be pushed.

Thank you for the laugh. I clicked you a, "like" for that.

 

Yes, it is, if the basket is the whole universe. It also like a flying helicopter in a sealed box, the helicopter does not have to consider any problem of momentum conservation with the box, it just need to push the air. The vacuum is just like the air, it can be pushed also.

If quantum vacuum (energy) fluctuations can be pushed then you have IMO a 'free energy' zero point energy machine where speed (v) is directly proportional to energy. The kinetic energy of that system can be extracted at KE = 0.5 • m • v2. The kinetic energy of an object is directly proportional to the square of its speed so for a fourfold increase in speed, the kinetic energy will increase by a factor of sixteen with energy input increases linear with velocity, constant power to produce constant thrust and no propellant.

Kinetic energy would exceed input energy at some point if it worked.
Example:

 

Thank you for the laugh. I clicked you a, "like" for that.

Not fair! I have to work much harder than that to get a "like"!

 

If the principle you're talking about is so simple, it should be fairly easy and inexpensive to build a small working prototype.

Not when he has to address the question I raised in #34.

 

Not when he has to address the question I raised in #34.

You're right... I guess I'll just have to go and stand at the back of the line and wait for my turn

 

I wasn't arguing your point to the TS. You're right on - if it's so easy, go do it.

I was reiterating that it's one thing to discuss a Maxwell's demon on paper, but quite another to go build one.

 

You can get thrust from a directional antenna.

Can you elaborate? I mean, can there be thrust in a vacuum, without moving a mass as a propellant, or is the thrust due to the surrounding air, a sort of local wind.

 

Can you elaborate? I mean, can there be thrust in a vacuum, without moving a mass as a propellant, or is the thrust due to the surrounding air, a sort of local wind.

It's the principle of a photon engine. The propellant is the photon energy and momentum that causes radiation pressure as described in the video I posted in this thread. Very inefficient.
https://en.wikipedia.org/wiki/Radia....28using_classical_electromagnetism:_waves.29

 

Can you elaborate? I mean, can there be thrust in a vacuum, without moving a mass as a propellant, or is the thrust due to the surrounding air, a sort of local wind.

Photons carry momentum and when you change the direction of the photon (such as by reflection) the momentum of whatever reflected it has to change in an equal and opposite manner.

The effect is small, but real (and was first demonstrated and measured well over a century ago). It takes a sail that is half a mile on a side to produce a pound of thrust at our distance from the sun.

But, given even pretty reasonable amounts of time, that can have a huge effect. 1 lb acting on a 1 ton mass over the period of 1 year would be accelerated to around 100 miles per second (if I did the math right). That's because there's a LOT of seconds in a year! (over 30 million).

 

OK, I get all that. It's the TS's proposal I'm not getting.

 

OK, I get all that. It's the TS's proposal I'm not getting.

That's because there's nothing to "get"... I think that the OP is confusing physics with mathematics, and he doesn't have a thorough understanding of either one.

 

OK, I get all that. It's the TS's proposal I'm not getting.

The TS seems to think there is someway to get the same effect (thrust) with a closed system by saying vacuum is the coupling from inside the box to the rest of the universe. His proposal would magically create a portal that can extract energy/momentum from some external point in space into his magic box that can be directed in some direction causing an increase in velocity and/or KE of his magic ZPM box.

It's a common thing in Science Fiction.
https://en.wikipedia.org/wiki/Ancient_technology_in_Stargate#Zero_Point_Module
https://en.wikipedia.org/wiki/The_Songs_of_Distant_Earth

 

Well there is the one aspect of the 'vacuum of space' that is being largely overlooked.

It's not really an empty void but does in fact have a huge amount of other non elemental 'stuff' moving about in it that can be physically interacted with via electromagnetic and such fields and effects.

 

But, given even pretty reasonable amounts of time, that can have a huge effect. 1 lb acting on a 1 ton mass over the period of 1 year would be accelerated to around 100 miles per second (if I did the math right). That's because there's a LOT of seconds in a year! (over 30 million).

Yebbut, how do you perform an emergency stop or course change?

 

Well there is the one aspect of the 'vacuum of space' that is being largely overlooked.

It's not really an empty void but does in fact have a huge amount of other non elemental 'stuff' moving about in it that can be physically interacted with via electromagnetic and such fields and effects.

It's not being overlooked but the odds of it being utilized by a simple resonant RF cavity (like the EM Drive) is pretty small.
https://en.wikipedia.org/wiki/Quantum_vacuum_thruster
Fringe science explained here: http://arxiv.org/pdf/1012.5264v1.pdf

2. PROPELLANTLESS PROPULSION 2.1 Global Constraint Regardless of the mechanisms that might be entertained with regard to "propellantless" or "field" propulsion of a spaceship, there exist certain constraints that can be easily overlooked but must be taken into consideration. A central one is that, because of the law of conservation of momentum, the center of mass-energy (CM) of an initially stationary isolated system cannot change its position if not acted upon by outside forces. This means that propellantless or field propulsion, whatever form it takes, is constrained to involve coupling to the external universe in such a way that the displacement of the CM of the spaceship is matched by a counteracting effect in the universe to which it is coupled, so as not to violate the global CM constraint. Therefore, before one launches into a detailed investigation of a proposed propulsion mechanism it is instructive to apply this principle as an overall constraint to determine whether the principle is violated. Surprising subtleties may be involved in such an assessment, as illustrated in the following example.
2.2 An Example: "E H× " Electromagnetic Field Propulsion
...
A recurring theme in electromagnetic propulsion considerations is that one might employ crossed electric and magnetic fields to generate propulsive force, what we might call E H× propulsion. The idea is based on the fact that propagating electromagnetic fields (photons) possess momentum carried by the crossed (orthogonal) E and H fields (Poynting vector). This raises the issue as to whether static (i.e., non-propagating) E H× fields also constitute momentum (as the mathematics would imply), and in particular whether changes in static fields could result in the transfer of momentum to an attached structure.
...
Pursuit of the linear thrust possibility, however, leads one to a rich literature concerning so-called "hidden momentum" that, perhaps surprisingly, denies this possibility.7 The "hidden momentum" phrase refers to the fact that although the linear E H× fields do carry momentum as in the angular case, the symmetry conditions for the linear case are such that there exists a canceling mechanical momentum contained in the structures even though a structure's CM itself is stationary (see Appendix A). Specifically, it can be shown on very general grounds that, contrary to the case for angular momentum (e.g., the Feynman disk), the total linear momentum of any stationary distribution of matter, charge and their currents, and their associated fields, must vanish. In other words, barring a new discovery that modifies the present laws of physics, any such distribution cannot generate a propulsive force without emitting some form of reaction mass or energy, or otherwise imparting momentum to another system8 .
...
Eqs. (A5) and (A3) demonstrate that the electromagnetic momentum is balanced by an equal and opposite mechanical momentum. Because of its rather obscure nature, this momentum has been referred to in the literature as “hidden momentum”. This is a particular example of the general result that a net static linear field momentum will always be balanced by an equal and opposite hidden mechanical momentum. In practical terms, this means that the creation of linear field momentum cannot give rise to motion because the field momentum is automatically neutralized by a mechanical momentum hidden within the structure, so that the whole system remains stationary. This inability to utilize linear field momentum for propulsion is guaranteed by the law of momentum conservation.

 

Yebbut, how do you perform an emergency stop or course change?

Carefully and slowly.

Fortunately, in space, there are very seldom any need for abrupt actions, at least with adequate planning. I'm not away of any occasion in which unplanned maneuvers had to be undertaken (except during the Apollo program, but that is very different than using a solar sail for long range propulsion). Even the space probes going through the heart of the asteroid belt simply went through ballistically. So you plan the route and maneuvers long before launch and your necessary corrections are all detected earlier enough that minor thrust changes applied over an extended period of time are sufficient.

 

I want to be able to do doughnuts in space.

 

3D doughnuts.

 

I want to be able to do doughnuts in space.

So what's stopping you?

 

Well I use to think gravity would, But as soon as I receive my vacuum pump, I’m gone.