Status of the "Warp" drive

[PB666]

I am going to paraphrase NASA and other sites.

"

The bad news is that the bulk of scientific knowledge that we have accumulated to date concludes that faster than light travel is impossible.

.....centers/glenn/technology/warp/warpstat.html........

, there are some other perspectives; tachyons, wormholes, inflationary universe, spacetime warping, quantum paradoxes...ideas that are in credible scientific literature, but it is still too soon to know if such ideas are viable.

Inflationary universe is possible given that the period of inflation all fields merged into one, that by quantum mechanics could have inflated as a single point in space, possibly making it unstable and causing spatial expansion. Tachyons seem like an impossibility, wormholes are possible but would take a huge amount of energy to transport the smallest amount of mass. Quantum paradoxes are possible but only on the smallest of scales.

Wormholes can occur by the distortion of space-time. Inertia and gravity are a product of energy that give rise to mass (Mass energy equivalence). If one has enough energy density then it can warp space-time to a degree that a wormhole is created, bending space, the problem the only levels of energy that are even close to wormhole energies are those that occur at the event horizon of black holes, and thus you could create a wormhole, but then you would need something to counteract inertia and gravity. Get two of these monstrosities going and

Next, just charge ‘em up to some incredible voltage, and spin them up to near the speed of light -- both of them.

warpstat.html........

Works for me. just make sure its my ashes.

This leaves Alcubierre’s "Warp Drive"

this moving section of spacetime is created by expanding spacetime behind the ship , and by contracting spacetime in front of the ship

To do this requires negative energy and generally preached in the form of negative mass. Negative energy might exist in zero-point energy, but it is not scalar to the requirement of generating enough differential to push space-time along its merry little way.

Using the "Inflationary Universe" perspective, for example, it is thought that spacetime expanded faster than the speed of light during the early moments of the Big Bang. So if spacetime can expand faster than the speed of light during the Big Bang, why not for our warp drive?

Something about infinite energy density strikes me as something that might be dangerous. But this then begs the question, how does the Universe make things move really really fast, but wait, aren't we moving realiy really fast relative to the average velocity of the universe, the universe is still expanding in all directions and so are we moving outward with our visible universe. Hmmm, this is not to dangerous, but then how did the universe get to this expansionary state. CMB, yeah but before that there was the opaque phase were energy became matter&anti and then photons and matter and so on until things spread out to the degree that matter could survive. This would have been to us a very violent phase. Prior to this the universe expanded at a temperature so hot, the temperature was immeasurable by any known method, because all known methods require matter. SO the acceleration takes place in inflationary phase which is too hot for any life, and then expands at a slower rate where matter is unstable and photons push out the boundaries of space and then everything cools down.

What about other good natural accelarations. We have acceleration into blackholes, black holes can make things change direction and move really fast. Not to shabby until the X-ray burst and gravitational gradiants tear everything apart. How about Supernova, they can accelerate stuff to the speed of light, of course the ignition sequence would be tuff on the ole bum.

So we have atomic bombs, certainly they can get things going.

I will just capture the highlights of the Alcubierre’s "Warp Drive"

Warp fields need to be propogated in front of a ship a light speed by some external lead (not the ship in the bubble) the ship then hitches a ride.

For 1 gram of hydrogen to traverse the galaxy by the minimal energy standard would take _all_ the energy in 84 km cubed of water (IOW water -> energy -> hitch a ride on a bubble).

Dr White proposes a small ship could be propelled by the energy equivelent (700kg) of a nuclear reactor burning million kilos of Uranium. Although no idea how to stably generate the exotic matter or negative energy.

The amount of negative energy required for such a propulsion is not yet known. Pfenning and Allen Everett of Tufts hold that a warp bubble traveling at 10 times light-speed must have a wall thickness of no more than 10^{−32} metersâ€â€close to the limiting Planck length, 1.6 × 10^{−35} meters.^[26] In Miguel Alcubierre's original calculations, a bubble macroscopically large enough to enclose a ship of 200 meters would require a total amount of exotic matter greater than the mass of the observable universe, and straining the exotic matter to an extremely thin band of 10^{−32} meters is considered impractical. Similar constraints apply to Krasnikov's superluminal subway. Chris Van den Broeck recently constructed a modification of Alcubierre's model that requires much less exotic matter but places the ship in a curved space-time "bottle" whose neck is about 10^{−32} meters.

So current resolution is somewhere down in the 10E-10 range we are off by a factor of 10E22.

So, can we do it?

NASA

http://www.nasa.gov/centers/glenn/technology/warp/socanwe.html

= No.

Edited February 26, 2015 by PB666

[K^2]

For FTL warp, pretty much, yes. That's the current state of things. Sub-light warp is still on the table.

[Bill Phil]

For FTL warp, pretty much, yes. That's the current state of things. Sub-light warp is still on the table.

If so, we could get to the nearest star in little over 4.5 years, right?

[dharak1]

How would bending space for warp interact with planetary systems? Because doesn't gravity bend space the same way an Alcubierre Drive does or am I missing something? Could we get to Jupiter in a few weeks or months using the Alcubierre dive or is there some reason that would be unsafe?

[K^2]

Energy requirements tend to be quadratic with speed for all known warp configurations. I don't see why it'd suddenly stop being the case. So with current-to-near-future tech levels, we'd be limited to hundreds, perhaps thousands of km/s. Which is great for in-system operations, but not going to cut it for interstellar.

How would bending space for warp interact with planetary systems?

The space-time is "almost flat" around here. So the warp drive can still operate. There will be "side effects". Unless you want to be wasting huge amounts of energy to compensate, energy and momentum are going to be conserved throughout the warp. Which means that if you want to head out from Earth to, say, Mars, you will need to put yourself on a trajectory that can actually reach Mars' orbit before you engage warp. The trajectory itself will also be curved by gravity. This isn't exactly a requirement, but "accelerating" warp bubble tends to interact with interstellar medium in a way that will also cause huge energy losses. So you want the warp bubble to "coast" in the gravitational field.

So roughly speaking, a sub-light warp from Earth to Mars would require the ship to break Earth's orbit and get to an Earth-Mars transfer using chemical rockets, ion drives, or any other conventional propulsion system. It will then engage warp to travel at something like 100-1,000km/s along an almost straight line towards Mars. There it will drop out of warp and use conventional propulsion again to enter Mars' orbit.

You still need to be able to build a ship that can reach Mars. What you're really winning with sub-light warp is time. Instead of getting there in 7-8 months, you can get there in a day or less.

Edited February 26, 2015 by K^2

[kerbiloid]

Schroedinger teaches us that in any moment any object presents in any location of the Universe - with some probability.

The last bit yet remaining - to roll your probability maximum to the location you want.

[rtxoff]

Schroedinger teaches us that in any moment any object presents in any location of the Universe - with some probability.

The last bit yet remaining - to roll your probability maximum to the location you want.

Ahhh yeah the wonderful Infinite Improbability Drive

[PB666]

Schroedinger teaches us that in any moment any object presents in any location of the Universe - with some probability.

The last bit yet remaining - to roll your probability maximum to the location you want.

As we think of objects (houses, cars, boats) need not apply. He is referring to things on the tiniest of scales. Again the collective argument about making improbable things behave collectively in quantum uncertainty. What was the name of the drive...for the Heart of Gold.."infinite improbability drive" in HHGTtG .

[K^2]

We do have Quantum Teleportation that attempts precisely that. The downfall is that such schemes require a classical channel to orchestrate the transfer, so you are still limited to light speed. They also get impossibly complex for macroscopic objects.

[PB666]

K-2 said:

It's the most precise field of Physics.

Its accuracy is due to its ability handle variation. Its not distinct in physics, I produce k = 5.35, the answer k = 5.35 +/- 0.06 (n=23) is a more definitive answer. If I then go on to state k = e^[1.67777 +/- 0.01115] informs on two other parts of the distribution.

K-2 said:

Most of Quantum Field Theory is really a branch of Linear Algebra. There are no "errors". No "random fluctuations". You keep talking about virtual particles, but you don't have a first clue what they are. They aren't fairy dust. They are off-the-shell excitations in the fields. As such, they can carry momentum between any two points in space-time, but the effectiveness drops exponentially with distance. The statistical improbability of what you are suggesting has enough zeroes to make scientific notation cumbersome. And you're shaking it like you've got something.

Lets just shake on this tree a bit then, a person accused of something should never short change his accuser.

Nature. 2011 Nov 16;479(7373):376-9. doi: 10.1038/nature10561. Observation of the dynamical Casimir effect in a superconducting circuit.Wilson CM¹, Johansson G, Pourkabirian A, Simoen M, Johansson JR, Duty T, Nori F, Delsing P.

"One of the most surprising predictions of modern quantum theory is that the vacuum of space is not empty. In fact, quantum theory predicts that it teems with virtual particles flitting in and out of existence. Although initially a curiosity, it was quickly realized that these vacuum fluctuations had measurable consequences--for instance, producing the Lamb shift of atomic spectra and modifying the magnetic moment of the electron. This type of renormalization due to vacuum fluctuations is now central to our understanding of nature. However, these effects provide indirect evidence for the existence of vacuum fluctuations.

From early on, it was discussed whether it might be possible to more directly observe the virtual particles that compose the quantum vacuum. Forty years ago, it was suggested that a mirror undergoing relativistic motion could convert virtual photons into directly observable real photons. The phenomenon, later termed the dynamical Casimir effect, has not been demonstrated previously. Here we observe the dynamical Casimir effect in a superconducting circuit consisting of a coplanar transmission line with a tunable electrical length. The rate of change of the electrical length can be made very fast (a substantial fraction of the speed of light) by modulating the inductance of a superconducting quantum interference device at high frequencies (>10 gigahertz). In addition to observing the creation of real photons, we detect two-mode squeezing in the emitted radiation, which is a signature of the quantum character of the generation process."

Although, admittedly Nature does not have the best reputation for field specific referee process.

Phys Rev Lett. 2012 Mar 2;108(9):093603.Photon production from the vacuum close to the superradiant transition: linking the dynamical Casimir effect to the Kibble-Zurek mechanism. Vacanti G1, Pugnetti S, Didier N, Paternostro M, Palma GM, Fazio R, Vedral V.

"

The dynamical Casimir effect (DCE) predicts the generation of photons from the vacuum due to the parametric amplification of the quantum fluctuations of an electromagnetic field. The verification of such an effect is still elusive in optical systems due to the very demanding requirements of its experimental implementation. We show that an ensemble of two-level atoms collectively coupled to the electromagnetic field of a cavity, driven at low frequencies and close to a quantum phase transition, stimulates the production of photons from the vacuum. This paves the way to an effective simulation of the DCE through a mechanism that has recently found experimental demonstration. The spectral properties of the emitted radiation reflect the critical nature of the system and allow us to link the detection of the DCE to the Kibble-Zurek mechanism for the production of defects when crossing a continuous phase transition.

"

A key point is to prove the predictions, however it is my prediction that not all the predictions about energy in vacuum space has been made, there are other orators on physics with well known names that have posited questions about the fields that permeate evacuated space and Im old enough to sit back and hear their point of view. It is plausible that they may have teased something in a way that gets useful. The deficit in the argument in the paper above is that photons have no mass, but photons teased out of the vacuum produce virtual electrons and positrons and they have mass. Again I am not arguing that I know the answer or that I am even going to do the math (cause Im not) but I am saying that there is still breathing room in quantum mechanics. The point I was making about this Cannae drive is by theory pure vacuum fluctuations that would be exploitable would be so rare, that this drive should not scale up without scalar size increases. If they placed the drive in space, it should deplete all potential local reaction mass rapidly and all that is left is virtual mass to push off of and given the above papers conclusions this mass is going to be of the smallest magnitude. With a photon drive I can dump photons at liberty, creating a degree of thrust, this cannae drive should reach a limit for a given area of space and plateau. I could be wrong, his resonator may be able to both tease VP out and impart momentum . . . . . .

But unlike magic reactionless drives

Point of debate I want to make clear here. You are the one calling them magic, in an attempt to create a biased argument. I am not. The point is that cause of the very weak force goes unexplained. One explanation was that they might be pushing off VP, the authors backed away from the argument, as I would also do in their case even if I believed it was the best explanation. In this way, scientist have got themselves in trouble before.

You and I are free to debate the cause, for the sake of the debate I am defending the plausibility VP and no more, but for the sake of debate you do not appear to be defending any plausible explanation just arguing that the VP explanation is bankrupt. OK so lets apply the same stringency.

, we understand the physics of warp. We can talk about what WOULD happen if we were able to satisfy the conditions. Even if it forever remains theoretical. Just like we can talk about what WOULD happen if Sun were to go Nova, or what WOULD happen if Earth got knocked out of its orbit, even if we have absolutely zero chance of making it happen.

One mans golden pond is another mans latrine. If the Sun were to go Nova earths orbital stats would be the least of its problems, we do know alot about Nova and some of the sequence, we do not know enough to proclaim the fate of inner planets left to orbit their star. The velocity of some Nova particles is so great that one could imagine the mantle layers undergoing a disintregative explosion into space as much of the lighter metal vaporized. Even before that sequence occurs earths orbit will degrade as the Sun expands into the inner planets, so Earth itself might be part of the implausible solar Nova. The problem with certain sciences were data is collected by examining one event after another is that they provide statistics, but if we look closely at the statistics the often lack critical details like confidence limits, the confidence limits and more important, the scrutiny of how they are determined are actually of greater importance than the discrete observation.

Lest dive into the physics of warp a little bit just to see how much we actually know. The field width they are proclaiming is 10E-32 meters, 3 magnitude above the lower limit of comptom wavelength (extreme gamma), essentially its a length of ~1000 'space pixels' across. It is thinner than the 50% confidence zone of a 4s electron orbital within a Xenon atom cooled to 0.1'K. It is 12 magnitudes smaller than a measurable distance with the roughest precision. So to say we know how to create a warp when we can't even measure the required thickness is a slop of an argument. Yeah, Yeah, this if for warp 10, but what they are trying to define is a sphere of Euclidean geometry which has a minimum to protect the payload from warped space-time. Even for lower warp those fields appear to be far more confined than can be actually measured. I do remember a few long nights spent in front of a JOEL 100KV electron microscope focusing the beam to get magnifications or 30,000X don't remember ever being able to focus that beam to get 100,000,000,000,000,000,000,000,000X. Maybe I know people who are working to get EM resolutions to 2.5 A on the EM don't know anyone who actually has the foggiest idea how to get 0.1A resolution, and that additional 21 magnitudes of 10 is off the horizon.

The argument itself is easily a flim-flam handwaving argument. To generate the field a ship has to travel in advance and lay down a field of negative energy in front, but the ship itself has itself be moving at warp speed to create the field or the field could be laid out across space like a railroad track, but the track itself would have to have a near infinite energy density in order to keep a stable field. Still theoretically possible, yes.........no. But that's not the end of this theoretical pursuit. The types of particles discussed, Tachyons and Negative energy come strait out of sci-fi. Occam's razor should apply to this logic.

1. Negative energy should exist because the Universe inflated. Well lets go through the very argument logically. The Universe may or may not have inflated. Inflation is the favored theory but multiverse can explain CMB without having to resort to inflation. The cosmic inflation theory holds that during the early Plank epoch that space-time had not resolved (space-time has now resolved), and that the Universe operated purely on Quantum physics (Relativistic and classic physics can be applied to most things now). At some point the universe was approximately infinite energy spread across one dimension (a point). Quantum mechanics suggest that the whereever that point was the pre-universe was also, and if it moved it statistically was all those points at once all the time. For whatever reason this state ceased and universe cooled. The bottom line is that the universe did not _need_ negative energy to inflate, it simply needed instability within the acting physics. This is a period of unification, the physics could allow many things or very restricted but unique physics. We get into bad logic when we begin to speculate excessively about what happened before CMB and negative energy as an explanation for inflation is just one such form of speculation.

2. Tachyons might be used to generate the field. This is one of the most absurd arguments I have seen, tachyons, a theoretical field that only travels at the speed of light and whose lowest energy state is at infinite speed can be set out to create a field in front of a ship. This is one of the reasons that quantum mechanics has some wiggle room, because relativistic physics still allow form many things, but some of the these things don't exist, at least in any form which we can detect or utilize.

3. That a field needs to be created in advance of the ship entering and the ship just catches a ride. This is an equally absurd argument and it really nails FTL, if the ship is not free to make the field and it therefore has to cross into the field, the field is a bubble (1/2 sphere is negative energy and 1/2 sphere being positive). The logic here is in order for the ship to move faster than light a third party needs to coordinate the movement of the bubble since the third party can't move faster than that speed it would need to be in front of the bubble signalling when each point along the path of travel became positively and negatively energized.

a. Therefore the ship either has to cross the space-time warp at the back of the bubble or at the front, given the bubble is traveling the speed of light it cannot cross into the bubble, the whole reason for crossing the bubble is to gain warp, if it is already traveling at light speed then it does not need the bubble.

b. crossing the warp would not be an enjoyable experience since it represents the same types of forces encountered at the event horizon of bh. That is the whole reason for creating flat space with a thin warp shell, the thin shell is to avoid the forces of the warp on the ship.

c. Once it crosses the bubble it has momentum in Euclidean space time it needs to immediately dissipate. So either it passes into a non-moving bubble slowly and stops in the bubble, or crosses a fast moving bubble and its momentum carries it out the other side. But the bubble's surface differentials are what make it move, which means for the ship to cross into a non-moving bubble, the bubble should not exist or be minimal. Once in the bubble the ship would have to signal the coordinator (at light speed) and the coordinator would then get the bubble moving. The alternative is the bubble is initiated from a point in space at a given time and progresses, the ship goes to that point and stops and waits, some other vessel at its target (say the next star) initiates the bubble and the ship moves. But the forces applied across these distances and at these resolutions are impossible.

d. Therefore, the bubble velocity and ships velocity need to be the same and thus the initiation of the bubbles light speed motion cannot be accomplished, the ship <<< C and if FLT requires the warp field to be applied well before the trip begins then and traveling at C or more then:

e. FTL using warp field is theoretically impossible for interstellar travel it may be impossible for warping short distances. What makes it theoretically impossible is a ship incapable of reaching light speed and accelerating to such speeds instantly cannot insert itself into a moving bubble and expect to stop once it get there. There is no way to precisely coordinate the creation and progression of bubble across interstellar distances.

4. For subluminal speed, it is probably still impossible, by stringent physics you use above:

a. Prove that negative energy exists and can be harnassed

b. Show that positive energy space-time warps can be generated to any sufficient degree without also creating destructive gravity.

c. Show that such a field 1 Angstrom thick can move without also moving the mass energy equivilant that also created the field

d. Since this questions requires proof of a, the question will be rephrased to accepts negative energies absence by doupling the positive energy requirement. Prove that any positive energy warp field capable of _moving_ any payload with 2X warp energy will not require more energy to create the field and move it than than the dV of the ship required to reach the same speed, travel and stop at its destination.

[kerbiloid]

As we think of objects (houses, cars, boats) need not apply. He is referring to things on the tiniest of scales. Again the collective argument about making improbable things behave collectively in quantum uncertainty. What was the name of the drive...for the Heart of Gold.."infinite improbability drive" in HHGTtG .

Please, don't forget that what you call your "body" is just a conglomeration of swirling clouds of elementary particles.

[Oafman]

If so, we could get to the nearest star in little over 4.5 years, right?

Yeah, but the problem is that we need to go to an interesting star, rather than to the nearest star.

If Proxima Centauri is just a red dwarf with no planets (we already know it has no huge planets) then I'm not sure it's worth the effort.

[KSK]

First of all, this appears to be a continuation of the 'Warp Navigation' thread further down the page. Could some kindly moderator please merge.

I'm not going to even get into the virtual particle discussion but I don't see anything to argue over in the warp discussion.

we understand the physics of warp. We can talk about what WOULD happen if we were able to satisfy the conditions. Even if it forever remains theoretical.

My emphasis added.

'Understanding the physics of warp' is not at all the same as 'understanding how to build a warp engine'. Indeed, understanding the physics of warp may very well tell you that a warp engine is impossible in practice, for all the reasons you mention. So arguing that K-2 is wrong because you don't think a warp engine can be built is pointless. It's a non argument because you're arguing against something that was never said.

[Red Iron Crown]

Merged threads, not sure why a new thread was necessary for this topic.

[PB666]

Yeah, but the problem is that we need to go to an interesting star, rather than to the nearest star.

If Proxima Centauri is just a red dwarf with no planets (we already know it has no huge planets) then I'm not sure it's worth the effort.

The Alpha Centauri system has an eccentric orbit around the galaxy at the moment it is a high-motion star with a mean radial velocity of ~ 25000 m/s towards us and will become breifly stationary 30,000 years from now at ~3 ly. It will then recede very quickly and by 100,000 years it will no longer be visible. In terms of targets for human settlement is a poor choice since you would not be able to maintain contact, and there is little evidence for planets in the habitation zone. The three stars appear to be part of a moving cluster that moves from 8.3 to 9.5 kpc relative to the galactic center.

Proxima undergoes increases in brightness because of magnetic activity. Planets in the central part of the goldilocks would experience episodic xray emmissions a couple of magnitudes greater than the earths outer atmosphere. In addition the planets would have to be so close to the star that the surface might be tidally locked such that a single face always faces the star. There are claims that such strong episodic radiation would strip the planet of any atmosphere, it would be like a dim version of mercury. That is the bad news, it will be a main sequence star for the next 400 trillion years and getting out of the proxima system is alot easier than the solar system. One could build a restaurant at the end of the universe there, of course the merging of andromeda may interfere with future party plans.

Proxima centauri might be a good choice in 25,000 years once systems within out solar systems local group have been colonized, because one can use the star to hitchhike to other clusters that can be colonized. This appears to be a good part of the galaxy to look for stars with habitable planets.

- - - Updated - - -

First of all, this appears to be a continuation of the 'Warp Navigation' thread further down the page. Could some kindly moderator please merge.

I'm not going to even get into the virtual particle discussion but I don't see anything to argue over in the warp discussion.

My emphasis added.

'Understanding the physics of warp' is not at all the same as 'understanding how to build a warp engine'. Indeed, understanding the physics of warp may very well tell you that a warp engine is impossible in practice, for all the reasons you mention. So arguing that K-2 is wrong because you don't think a warp engine can be built is pointless. It's a non argument because you're arguing against something that was never said.

I disagree, I am using the same stringency he has applied is perfectly legitimate. In any case he says he thinks subluminal velocities might be possible, so that the level of stringency he is applying lets see if he can defend the concept.

Let me emphasize one point, I am not against FTL travels possibilities, it may be possible but our current understanding of physics does not practically allow it. It may be possible to create a field in some space laboratory and move something in that field a few microns per second. That is not what the proponents were arguing, they were talking about inserting objects in spherical bilaterally opposed energy fields travelling through space at greater than the speed of light where some of the essential components needs to maintain that field had not been discovered. It appears if they were trying to warp the "Star Trek" version of a warp field into a reality.

K-2 and I differ on one essential point, he thinks that we know enough about physics to include or exclude theoretical possibilities based solely on theoretical grounds. My opinion is that we don't, we may know alot about physics in the context of the observable universe, but the nature of the Universe argues that is not enough to complete our understanding. I have not brought string theory or highly exotic matter or any red herring into the arguement, I am simplly claiming that there is space to dot i's and cross t's and areas of discovery, however, minor that might shed light on the reaction-less drives function.

Edited February 27, 2015 by PB666

[K^2]

The deficit in the argument in the paper above is that photons have no mass, but photons teased out of the vacuum produce virtual electrons and positrons and they have mass.

This is totally irrelevant. Lets say photons had mass. Hell, you can simply uze the Z bosons. They're massive, and they're produced in Quantum Vacuum just as easily. If they are virtual, they cannot leave the ship. In order to propagate freely to any finite distance, a particle must be on the shell. Otherwise, it has a decaying amplitude. If it is on the shell, then E² = m² + p². And now you not only have to waste energy to gain momentum, but also to generate that mass. You might as well propose generating matter and anti-matter and expelling that.

This is not something new. This isn't some exotic fields, or some new state we are discussing. These are the absolute basics of particle theory. And they arise from the absolute fundamentals for field theory. We are talking about conserved currents of fundamental symmetries. You can invent any particles you want, with any interactions you want. You can fill vacuum with any families of virtual particles. You can give vacuum as much energy/mass as you want. You still cannot create a current without giving it energy that at least satisfies E = pc. This is the absolute minimum of energy you need to generate propulsion. Period. In any vacuum. With massive or massless photons. With virtual or real particles. This is like me telling you that "Sum of two even numbers is even," and you telling me, "But what about 6 and 8? Have you considered 6 and 8?"

Lest dive into the physics of warp a little bit just to see how much we actually know. The field width they are proclaiming is 10E-32 meters

I'm not going to break it down to every single point, because I can stop it on the very first one. The thickness of the bubble is some sigma. It is a parameter. It is a parameter that can be varied in time, and it is a parameter that can be varied in magnitude around the ship. In the simplest geometry, the Alcubierre drive, the warp bubble is spherically symmetrical and invariant in time. There, the thickness is a constant, and reducing the thickness reduces the amount of negative energy needed for warp. This is one special case, which is only useful for illustration.

The physics of the warp drive is contained within the relationship between interior and exterior metrics. Your entire analysis is like trying to prove that flight is impossible because you've only considered wings with square cross-section made out of solid oak. No **** Sherlock. Now, how about proving that negative energy is a requirement in a general case? Oh, wait, you can't even do the computation required to demonstrate that energy is negative in the basic example given.

And just to make this a touch more interesting, the frame dragging in the viscinity of a rotating black hole works pretty much like a sub-light warp drive with very thick bubble. Still not achievable, and comes with a whole bunch of unwanted side effects even if it were, but your entire argument on requirement of negative energy collapses on itself.

Again, the difference is that Warp Drive is derrived from well-understood theory. We haven't figured out a practical configuration yet, and it might not exist. But we do not know any reason why such configuration wouldn't exist. On the other hand, EMDrive contradicts every available theory in the most fundamental way. We do know the exact reasons why it cannot exist. Are you grasping the difference here?

[Bill Phil]

Yeah, but the problem is that we need to go to an interesting star, rather than to the nearest star.

If Proxima Centauri is just a red dwarf with no planets (we already know it has no huge planets) then I'm not sure it's worth the effort.

It's still worth it to send probes, though.

And sublight travel at large fractions of C would be helpful for getting around the solar system.

[PB666]

This is totally irrelevant. Lets say photons had mass. Hell, you can simply uze the Z bosons. They're massive, and they're produced in Quantum Vacuum just as easily. If they are virtual, they cannot leave the ship. In order to propagate freely to any finite distance, a particle must be on the shell. Otherwise, it has a decaying amplitude. If it is on the shell, then E² = m² + p². And now you not only have to waste energy to gain momentum, but also to generate that mass. You might as well propose generating matter and anti-matter and expelling that.

As the paper notes quantum vacuum is capable of generation virtual particles, although it notes only photons. As you point out why not other particles, however I was reluctant to go that far because these exotic virtuals may be so uncommon within a vacuum as not to be useful. So basically we are talking around each other, your thinking of virtuals is that they only are useful in explaining field transfers, like the binding of an electron to a proton. Whereas other people are describing VP that exist in space. Of course there is no space completely devoid of persistent ripples in the field like photons. So the argument is made complex. But the two papers are arguing about how they manipulated these VP.

This is not something new. This isn't some exotic fields, or some new state we are discussing. These are the absolute basics of particle theory. And they arise from the absolute fundamentals for field theory. We are talking about conserved currents of fundamental symmetries. You can invent any particles you want, with any interactions you want. You can fill vacuum with any families of virtual particles. You can give vacuum as much energy/mass as you want. You still cannot create a current without giving it energy that at least satisfies E = pc.

You are repeating yourself, I get this from the very first posts. I agree that there has to be some symmetry, the problem is not that its how. I am speculating that the assymetry created is tucked into vacuum space and handed of by other virtuals that appear later. In the Feyman diagrams the photon produced by the electron is a function of the electrons properties, so why not be the same, the VP appears and disappears, occasionally appears and hands back its momentum to another Fermion and then disappears. This is my basic contention, if this is a result of assymetries that are create in vacuum fields then they may cause feed back causing the apparatus to decrease thrust and eventually that energy may end up back in the devise itself as waste heat.

This is the absolute minimum of energy you need to generate propulsion. Period. In any vacuum. With massive or massless photons. With virtual or real particles. This is like me telling you that "Sum of two even numbers is even," and you telling me, "But what about 6 and 8? Have you considered 6 and 8?"

it does sound like that, I admit, I am trying to keep the door open, not slam it shut. It means that for a period the momentum might have vanished. What I am proposing is that momentum is transferred by VP through the vacuum only to be dumped of an unsuspecting mass on the other side of the force detector. There is reaction mass, but that mass ends up not being on the ship. So if there is no mass to dump on what happens? Let me make an analogy - in a inflationary universe there was very high density of energy but there was no mass, you cant measure gravity and but with infinite energy binding the universe together it should have been incredibly massive. The paradox is that as the universe cooled universe lost energy and therefore potential mass but gravity becomes more apparent because there is more mass around. Gravity was one of the first of the forces to appear, but what inertial body can attest to the attraction. The highest gravities in the universe paradoxically are apparent after it has cooled and mass has coalesced into black holes.

Again we need to see the devices performance with no possible mass to push off of.

I'm not going to break it down to every single point, because I can stop it on the very first one. The thickness of the bubble is some sigma. It is a parameter. It is a parameter that can be varied in time, and it is a parameter that can be varied in magnitude around the ship. In the simplest geometry, the Alcubierre drive, the warp bubble is spherically symmetrical and invariant in time. There, the thickness is a constant, and reducing the thickness reduces the amount of negative energy needed for warp. This is one special case, which is only useful for illustration.

And how is this less than atom thickness field generated? The reason the feild is thin is to protect the contents of the bubble from the field this is thoroughly explained.

The physics of the warp drive is contained within the relationship between interior and exterior metrics. Your entire analysis is like trying to prove that flight is impossible because you've only considered wings with square cross-section made out of solid oak. No **** Sherlock. Now, how about proving that negative energy is a requirement in a general case? Oh, wait, you can't even do the computation required to demonstrate that energy is negative in the basic example given.

I get why they require negative energy, the differential from the front to the back of the bubbles shell is what propels the warp forward.

And just to make this a touch more interesting, the frame dragging in the viscinity of a rotating black hole works pretty much like a sub-light warp drive with very thick bubble. Still not achievable, and comes with a whole bunch of unwanted side effects even if it were, but your entire argument on requirement of negative energy collapses on itself.

Not my arguement, that is what was stated. A negative energy field in front of the device and a energy field in back. What I said was FTL may be plausible but not with this physics.

I am holding the warp argument to your stringency on dealing with the Cannae drive. By your stringency the warp drive as defined by Alcubierre drive should not be physically possible

Again, the difference is that Warp Drive is derrived from well-understood theory. We haven't figured out a practical configuration yet, and it might not exist. But we do not know any reason why such configuration wouldn't exist. On the other hand, EMDrive contradicts every available theory in the most fundamental way. We do know the exact reasons why it cannot exist. Are you grasping the difference here?

As opposed to the Cannae that appears to work by some unknown mechanism in which the theoretical reasoning why has not been worked out. How does the saying go...Physician heal thyself. The arrogance of your perspective is somewhat boggling. "I can't be wrong because we got the theoretical physics all worked out".

This we who claims it needs negative energy or negative mass - you deny.

I gave you a very simple problem, I shaved down the neccesity for all the superluminal problems and yet you can't even justify the subluminal warp, so how is it that you expect me to believe that superluminal warp engines are even possible.

[KSK]

I gave you a very simple problem, I shaved down the neccesity for all the superluminal problems and yet you can't even justify the subluminal warp, so how is it that you expect me to believe that superluminal warp engines are even possible.

Again, the difference is that Warp Drive is derrived from well-understood theory. We haven't figured out a practical configuration yet, and it might not exist.

Yes - you are talking past each other. And I laughed at the 'very simple problem' part. Because warp drive is clearly a very simple problem.

Edited February 27, 2015 by KSK

[PB666]

Yes - you are talking past each other. And I laughed at the 'very simple problem' part. Because warp drive is clearly a very simple problem.

Subluminal warp takes out the most difficult aspects of FTL warp, you don't need precessional coordination, you can potentially 'link' the warp fields to the ship, the bubbles shell can be thicker . . . . . . .

If you cannot theoretically find a way to do this low energy version light speed warp and above is certainly impossible.

If one can take the stated components.

1. negative energy/mass in front molded to from a half-hemisphere with highest density on the leading tangential

2. positive energy/mass in back ..........

3. got it to move a flea 1 millimeter

Then you would have some expert (2-K) claiming you did not have negative energy, the flea moved by hopping, but I might concede that this is better defined physics than the Cannae drive.

[K^2]

PB666, you keep using words you don't understand. Your entire paragraphs are devoid of any meaning. Especially this gem.

I am speculating that the assymetry created is tucked into vacuum space and handed of by other virtuals that appear later.

There are words. There are even phrases that might mean something. But the sentence is meaningless. "Assymetry tucked into vacuum space"? And "Handed of by other virtuals"? This isn't poetry. This crap might fly in a theology discussion. Or some branches of pseudo-philosophy. But it's useless babble just about anywhere. There is no practical application to any of this.

The symmetry in question is the local gauge symmetry. That might sound like just words to you, because you have made zero attempt to learn any science. But to anyone who has had to deal with gauge theory, it is a mathematically precise statement. It means that we have a symmetry group that can be applied to the Lagrangian of the problem. That the Lagrangian is invariant under the symmetry transformation. That furthermore, we introduce a gauge field to allow the Lagrangian to be invariant under the continuous field of local transformations. That Yang-Mills theory can be applied. That there is going to be an interaction field, for which we can write an interaction Lagrangian. And so on, and so on.

For every single one of these sentences, there are precise mathematical formulae.

And you are proposing handing these off to virtuals? Handing what exactly? The mathematical group? Or the formulae? Do you want to write down these equations on the paper and pass them off to virtual particles as notes?

Your first order of business needs to be to stop using words you do not understand. Second, if you want to actually understand how something works, which is a prerequisite for discussing it, you need to learn formulae that go into it. You then need to learn to structure your sentences to reflect the mathematical relationships between concepts you are describing.

For example, if I was going to tell you that for small amplitude, the period of oscillation of a pendulum depends only on gravity and length of the arm, what I am really saying is that given a mass m suspended by an arm of the length L, making a displacement angle x with the vertical, the equation of motion for the pendulum is mx'' = -mg/L sin(x), which can be approximated for x<<1 as x'' = -x g/L, which has a period of 2 pi sqrt(L/g). There is a precise formula that goes with the statement.

If you want to talk about any scientific principle, you have to communicate in just as precise a fashion. Because if you do not, you are just making stuff up and make yourself look bad.

I get why they require negative energy

No, you do not. You have more words to go with it that have zero meaning. To get this, you need to be able to compute it. Can you compute energy density associated with Alcubierre Metric? Do you know where to even start? And I'm pretty sure these are rhetorical questions.

[KSK]

OK, I'm stopping here. Life is too short to listen to any more of this blethers. From PB666 I hasten to add.