Alcubierre Drives, Matter, Space and everything else.

Originally posted by Larryman
Ok, thanks. I'll stick with "Extended Heim Theory" then. I don't think it has such outrageous exotic matter requirements. It uses a different principle of operation for it's f-t-l travel - the elimination of mass from matter. It seems more acheivable to me, than warp drive.

Hi Larryman, I think you got that backwards.

The Alcubierre drive is indeed highly speculative, but it seems like every time somebody takes a closer look at it it's not as unrealistic as originally thought. And it is a valid solution of Einstein's field equations. Regarding the exotic matter requirements:

Exact solutions in general relativity

Some doubt has been cast upon whether sufficient quantity of exotic matter needed for wormholes and Alcubierre bubbles can exist.[3] Later, however, these doubts were shown[4] to be mostly groundless.

I still have doubts, but nothing that comes close to the doubts I have about extended heim theory. It's so far outside the mainstream there's really little reason for me to find it credible. You can read more about that topic on this web page:

Talk:Heim theory

With a total of 8 citations (and even if a few more can be found) Heim theory just does not rate. It is clear that, whatever its merits or demerits, Heim theory is outside the current consensus of the scientific mainstream.

Translation: it's almost universally ignored by the mainstream scientific community. That doesn't prove it's wrong, but it certainly does nothing to lend it credibility either. So I'm astonished anyone would think it's a more likely solution than the valid solution to Einstein's field equations, unless you just weren't aware of all this.

reply to post by Arbitrageur


Yes, I'm aware the mainstream scientific community ignores Extended Heim Theory, rather than simply testing it by spinning a strong superconductor magnetic material. That's our loss, in my opinion.

Originally posted by drakus

But that article made me ask the question I always ask about this:

1) what effects would the creation of this "wave" in space-time have on the surrounding space and "stuff in space"?
and
2) What is the difference between matter and space?
(which I asked "off-topicly" in the cited thread so, sorry about that

)
I know number 2 sounds stupid, but I could never see the real difference, beside the obvious...

For 1: If you wanted to arrange a collection of matter / energy so as to produce the Alcubierre metric, on scales of order of a reasonable starship, you would need absolutely crazy energy densities- and in front of your ship you would need an incredible amount of negative energy, which we aren't even sure is possible, and which we have strong reasons to believe is strictly impossible. en.wikipedia.org...

Even assuming you could assemble the necessary energy densities and negative energy densities required for this metric, the net effect of it travelling through space would be like a snow plow to matter. Anything anywhere close to your warp drive and not in the bubble would be ripped to shreds by extreme tidal forces.



For 2, there are clear differences between spacetime and matter when you study Einstein's equations in general relativity. For one thing, Einstein's most basic field equation shows how the curvature of spacetime relates to its energy content. It doesn't say that spacetime and matter are exactly equal. If they were, we'd only have to know what the energy content of a particular distribution of matter was in order to know what space was. The relationship is a lot more complicated than that.

Secondly, mass/energy lives in spacetime, which makes it pretty hard to confuse the two. If you want to get very exact, there is a precise way in which the two are not the same, proven by the Coleman–Mandula theorem:
en.wikipedia.org...

reply to post by CLPrime

but that manifold is a tensor field

What?!

A metric tensor(field) is a function defined on a manifold that takes in two tangent vectors and produces a scalar quantity. Thus a metric tensor assigns a metric to each point in the manifold.

Originally posted by moebius

A metric tensor(field) is a function defined on a manifold that takes in two tangent vectors and produces a scalar quantity. Thus a metric tensor assigns a metric to each point in the manifold.

Yep...and all of that was contained within my "is". Remember, it all depends on what your definition of "is" is.
Also, it might help to know that, when I was saying that, I had food poisoning and didn't care to be quite so precise.

When CERN announces there is no Higgs particle, what affect will that have to the Alcubierre warp drive theory?
If Alcubierre warp drive is based on Einstein's Relativity, which requires Higgs mass particles... then it would seem there should be some affect on the theory.

reply to post by Larryman


Relativity does not require the Higgs boson. In fact, the Higgs is a non-relativistic particle predicted by the Standard Model. In my opinion, Relativity is, for the most part, accurate, and I also don't believe the Higgs exists - these are two unrelated issues.

I love these types of discussions, I actually enjoy having my brain hurt

I have a basic understanding of relavity and I love it, I have great fun explaining how it is possible to time travel into the future relative to earth And watching peoples expressions as thier brain hurts trying to understand the explanation.

When I first heard of inflation, I assumed the SOL was faster at the beginning of the universe, therefore it is not set in stone. If you could create a space time bubble like your own universe, you could massively increase the SOL and voila FTL travel.

After finding out that it is space that expands (still cant get my head round that, will read the links in this thread), I came to the conclusion in this thread: Compress the space ahead and expand the space behind the ship. But I have never seen a decent video or other explaining how space can expand without expanding matter as well (or at least the space within matter as even solid objects are 99% empty space).

Just had a lol thought, this is how the engine in futurama works; the ship stays still, it moves the universe around it. Well close enough anyway.

Originally posted by DJOldskool

Just had a lol thought, this is how the engine in futurama works; the ship stays still, it moves the universe around it. Well close enough anyway.

Which is, in fact, a perfectly legitimate way of looking at most anything. When you drive in your car, the car's not moving, you're moving the Earth under you. As I'm sure you know, this is a key aspect of Relativity.

Originally posted by CLPrime
reply to post by Larryman

 

Relativity does not require the Higgs boson. In fact, the Higgs is a non-relativistic particle predicted by the Standard Model. In my opinion, Relativity is, for the most part, accurate, and I also don't believe the Higgs exists - these are two unrelated issues.

So, I guess it is also the Standard Model theory that is the source for the exotic matter that is needed to create the warp bubble. So... if CERN finds no Higgs boson particle... then the Standard Model theory falls apart. Then there is no exotic matter for the warp drive. Is that correct?

Originally posted by Larryman
So, I guess it is also the Standard Model theory that is the source for the exotic matter that is needed to create the warp bubble. So... if CERN finds no Higgs boson particle... then the Standard Model theory falls apart. Then there is no exotic matter for the warp drive. Is that correct?

I wouldn't say that, it's not exactly yes and not exactly no.

This article provides some interesting insight to answer that question (SM means Standard Model):

SM Higgs and MSSM Higgs Dead?

The Higgs sector does not look like what the standard model predicts. ...

This doesn't mean that the Standard Model itself is a bust. The Higgs boson is a mathematical gimmick to impart mass to particles in a theory that has no other means of doing so. It has the rather ugly feature of providing a source of inertial mass that is distinct from the almost Standard Model way of deriving gravity (the graviton), when general relativity suggests a much deeper connection between the two. It appears that this particular mathematical gimmick is the wrong one. Perhaps loop quantum gravity models will provide some insight into this issue.

...The failure to find the most familiar versions of the Higgs boson puts the pressure on theorists to explore new ways to address this problem that most of the theoretical physics community had complacently assumed had been solved and just had to be confirmed by experiment. This pressure may bring results. We'll see what happens next.

Originally posted by Larryman

Originally posted by CLPrime
reply to post by Larryman

 

Relativity does not require the Higgs boson. In fact, the Higgs is a non-relativistic particle predicted by the Standard Model. In my opinion, Relativity is, for the most part, accurate, and I also don't believe the Higgs exists - these are two unrelated issues.

So, I guess it is also the Standard Model theory that is the source for the exotic matter that is needed to create the warp bubble. So... if CERN finds no Higgs boson particle... then the Standard Model theory falls apart. Then there is no exotic matter for the warp drive. Is that correct?

Standard model or no, Higgs or no, we have no conceivable way of creating exotic matter.

To Arbitrageur:

The failure to find the most familiar versions of the Higgs boson puts the pressure on theorists to explore new ways to address this problem that most of the theoretical physics community had complacently assumed had been solved and just had to be confirmed by experiment. This pressure may bring results.

...then they should consider Extended Heim Theory.

To wirehead:

Standard model or no, Higgs or no, we have no conceivable way of creating exotic matter.

Since Alcubierre warp drive requires enormous quantities of exotic matter, and there is no conceivable way to create exotic matter, then... Alcubierre warp drive is dead.
So, they should test Extended Heim Theory for the f-t-l propulsion that it proposes can be acheived, without need of exotic matter.

reply to post by Larryman


That implies that a model's inability to bend to our will demands that it be wrong. We want to travel faster than the speed of light, but accepted theories doen't allow it, so we should look to another theory? Reality doesn't work that way. If Relativity is right, then we can't travel faster than light (aside from the theoretical Alcubierre drive), no matter how much we wish we could. And, if the Alcubierre drive isn't technologically feasible, then there's nothing we can do about it.

I want you to consider Heim's theory. Where are the extra particles we should be seeing, like the neutral electron? Heim's weaknesses are much more significant than those of accepted theories - which would be why not many are seriously considering it.

reply to post by CLPrime


"...theoretically [the neutral electron] has a small probability of occurring in every experiment involving particle collisions".
I guess we'll have to add the 'neutral electron' to the CERN search list, along with the Higgs boson.

If Relativity is right, then we can't travel faster than light (aside from the theoretical Alcubierre drive), no matter how much we wish we could.

That would assume that Relativity is 'all present', and that there can be nothing beyond it's governing domain. Do you think Relativity must also govern the physics of the universe(s) that bumped into ours, in it's early ages? And I don't see how Relativity can apply to the 'Bulk' emptiness (which I guess is hyperspace), in which the universes move to bump each other. In one of Dröscher and Häuser's papers, it is stated that the Extended Heim Theory starship is forced into hyperspace (due to it's altered matter composition) - thus allowing f-t-l speed. My understanding is that hyperspace/Bulk is beyond Relativity. Maybe my understanding is all wrong.

"Researchers Find Evidence of Other Universes Lurking in the Cosmic Background"
www.popsci.com...

Originally posted by Larryman
Do you think Relativity must also govern the physics of the universe(s) that bumped into ours, in it's early ages?

These are the kinds of questions it's fun to ponder over some beers because while they don't really have any meaningful scientific basis, they are fun to think about.

From your source:

But that’s a big “if.” If the earlier CMB findings by Penrose are any indicator, proving or disproving these sorts of claims rooted in WMAP data is extremely difficult.

So from a scientific perspective, the first question is, do these other universes exist? Ever since I read about dark flow I've been open minded to the possibility, but that wasn't really convincing evidence and the claim you referenced is far from conclusive. The truth is we really don't know, so that's the first question that we'd need to answer before tackling the question about the properties of the other universe.

Now to get a sip of my beer (actually it's coffee but beer would be better for this discussion), and discuss the possible properties of the other universes if they exist. It's human nature to be anthropocentric. We created god in our own image (unless it was the other way around as the bible states, though if there's no "god particle" does that mean there's no god? Just kidding), we even created aliens in our own image...the grays are actually us, in a way. They seem to have their origin in science fiction stories where writers imagined what we might evolve to look like in the future...increasingly hairless, increasingly larger heads and brains, more robots to do our physical work so we don't need large strong bodies, etc. I think it's human nature to think anthropocentrically, and that may be an error when considering alien life, since aliens may look nothing like us.

Now back to your question about physical properties in the other universes. We have no evidence, so all we can do is speculate, right? One way to do this might be to make a list of reasons why the properties might be the same and a list of reasons why the properties might be different. Since all our experience is based in our own reality in our own universe, I suggest the list will be biased on the "same" side. And I would go with that speculative answer, (along with the answer to the question of how many angels can dance on the head of a pin, it's 26). But I realize I may be biased, and if there is another universe, it could be different.

OK leaving the beer discussion and back to reality. We still have a lot more to understand about our own universe (as illustrated by the fact that we so far haven't found the elusive Higgs), so I don't think we're n a very good position to determine the properties of other universes. My guess is, determining if other universes even exist will prove to be difficult at best. And if the other universes are of the nature stated in the popsci article, and do exist, determining their properties may be impossible.

And lastly a question for you. Other than making for interesting discussion over a beer, does it really matter what the properties of the speculative other universe are? I mean, it's not like those properties will have any impact on us, right?

reply to post by Larryman


Ohhh...okay. You believe in multiple universes. And you believe that those universes "bump" into each other. This is one of those ideas that came out of the 90s, when scientists thought society would revert to the Stone Age in Y2K so they just tossed random crap around.

When you've spun that electromagnet and provided just one experimental confirmation of a prediction made by Extended Heim's Theory that isn't made by any other theory, then you've got something to work with. Until then, you might as well be considering bumper universes, 'cause none of it has any observational basis whatsoever.

Originally posted by CLPrime
Until then, you might as well be considering bumper universes, 'cause none of it has any observational basis whatsoever.

As our search for the Higgs is suggesting, that observational evidence is pretty important. The Higgs may not even exist, and multiverse theories are a lot more speculative than the Higgs from my perspective.

I'm impressed with all the research taking place on the cosmic microwave background. But since we are just measuring things like temperature fluctuations of millionths of a degree, and some polarization, sometimes I wonder how confident we should be about what that means. As a means of verifying theories that have other evidence, it seems reasonable, but as a primary source of evidence for another universe, it seems like more than a stretch to me.