Science Discussion

Wait, what?

I could be asking a silly question here but… how do you make an EM field push particle/antiparticle pairs in the same direction? As I understand it they’d have a tendency to be effected in opposite ways by it?

I mean I could see it happening if you had time to detect which is which and calibrate the field accordingly, but if you’re trying to do it all before the vacuum getting pissed off and setting it’s goons on you…

Ahh, you don’t make an EM field push the particle/antiparticle pairs in the same direction. You make three (or more) EM fields do it.

While I’m sure the devil is in the details, the basic concept is that you use one field to split the particle pairs and fire them off into two neighbouring fields. These neighbouring fields then generate the thrust.

So, you might use a magnetic field to split the particle pairs, sending the negatively charged particle toward a negative electric field, and sending the positively charged particle toward a positive electric field.

Or you may use a magnetic field to split the particles, and funnel them into appropriately polarized linear particle accelerators.

So technical consideration aside, there is actually solid science to back this concept up.
What is a bit off-putting is that this system pretty much looks like a reactionless drive. And while it does sound more credible than a Dean drive, there are also good reasons why reactionless drive are avoided in SF.
Just imagine, some probe is launched with such drive for an interstellar mission, with instructions to return some samples. And a playful hacker (or even human error) deactivate the “stop accelerating and slow down” for the return trip.
Then, makeshift RKV. Assuming a 10 000 kg probe with an terminal velocity of 0.333c, we get 5.44e19j, or about 10 000 megatons.
Or did I completely miss something?

Even without going that far, I’ve heard that a reactionless drive could be used to create a perpetual machine of the first kind (aka free-energy machine), though I can’t find how.

Of all the things things kind of drive is, reactionless isn’t one of them. Remember that the “reaction” in “reaction drive” comes from Newton’s second law: For every action, there is an equal and opposite reaction.

The action here is that the charged particles are accelerated toward the back of the ship. The reaction is that the ship is accelerated forward. Such a drive, on the largest scales anyway, works exactly the same as a standard chemical rocket. In chemical rockets, particles are accelerated to very high speeds using exothermic chemical reactions, and then shot out the back of the ship. In this case, particles are accelerated to very high speeds using magnetic feilds, and then shot out the back of the ship. The fundamental difference here is that in the case of a chemical rocket, those particles are loaded onto the ship before launch, and carried along with it, while in the quantum plasma thruster those particles are farmed from the quantum foam.

Don’t have to imagine it, it’s already happened before. Thankfully, this was all that was left when it reached Earth.

More to the point, though: while reactionless drives tend to violate the conservation of momentum, they mostly obey the conservation of energy, meaning that to put 5.44e19J into a space probe’s velocity you’d first need to put 5.44e19J into it’s reactionless drive. Oh yeah and there’s the bit where this one is not reactionless.

Well, apparently conservation of energy is not that simple. But as it is not a true reactionless drive (as in, no more than a plane propeller), it is less unbelievable.
That said, momentum is passed to the quantum foam. But then, when those particles disappear again, what becomes of this extra momentum? Is it carried by photons? Would it mean that more photons are emitted away from the engine than toward it? Could it be used to direct energy?

More importantly, could a similar principle be used to explain Infinity’s fuel-less thrusters?
Come to think of it, didn’t someone suggest something like that, but with an hypothetical Crayon particle instead of the quantum foam, on the old forums?

Conservation_of_Momentum[quote=“Runiat, post:65, topic:412”]
Don’t have to imagine it, it’s already happened before. Thankfully, this was all that was left when it reached Earth.
[/quote]

Yeah, that would help explain the Fermi paradox - and put a Great Filter right in front of us.
It wouldn’t be enough to explain the paradox entirely IMHO, so other solutions may complement it. But it doesn’t change the fact that we may very well be headed straight for a new problem, as a species.
Though wouldn’t RKV impacts be more visible than from stray protons?

The True Science of Parallel Universes by MinutePhysics Attention to be given near the end, around 4:13, were it says physics is science not philosophy. http://www.youtube.com/watch?v=Ywn2Lz5zmYg

Sorry, I can’t take a semantics-based physics argument serious unless it first addresses the atom inconsistency.

There’s nothing quite like an argument from false authority to fuel a raging hate-on, eh? Saying “physics is science, not philosophy” is like saying “my house is a square, not a rectangle”, or “I’m eating a cake, not a dessert”.

Seriously, what’s your problem with philosophy?

For the way it is being used here (not everyone) it is used by people who know little about science to pretend there points are just as valued as a scientist. People who know how to program that think they know as much as god. Makes me sick. People trying to fill the void in there High School life with pretentiousness, self-importance. [quote=“Kichae, post:69, topic:412”]
false authority
[/quote]

Is that me or the scientist to whom you refer? I’m linking science here. Philosophy can stay on the philosophy page.

Remarkable White Dwarf Star Possibly Coldest, Dimmest Ever Detected https://public.nrao.edu/news/pressreleases/cold-white-dwarf

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Great Scott! Giant diamonds not only in Uranus but everywhere?!

Cool that we can detect such faint objects.

Chimpanzee language: Communication gestures translated
http://www.bbc.com/news/science-environment-28023630

Common Physics Misconceptions http://www.youtube.com/watch?v=IM630Z8lho8

CU-Boulder instrument onboard Hubble reveals the universe is ‘missing’ light - See more at:
http://www.colorado.edu/news/releases/2014/07/09/cu-boulder-instrument-onboard-hubble-reveals-universe-‘missing’-light#sthash.12XbCJQM.dpufhttp://www.colorado.edu/news/releases/2014/07/09/cu-boulder-instrument-onboard-hubble-reveals-universe-‘missing’-light

That is a hefty url. :open_mouth:

Four-winged dinosaur is ‘biggest ever’
Biggest found SO FAR! Correcting the BBC, I do what I can.
http://www.bbc.com/news/science-environment-28295571

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Sandstone shapes ‘forged by gravity’ and how to make them. http://www.bbc.com/news/science-environment-28365410

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Mayfly swarm fools radar. This is just funny: http://www.bbc.com/weather/features/28448936

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Fluffy and feathery’ dinosaurs were widespread