Author Topic: Alcubierre drive - Updates and Discussion  (Read 134842 times)

Offline Star One

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Alcubierre drive - Updates and Discussion
« Reply #260 on: 12/09/2021 04:15 pm »
I'd love this to be true.  I really would.  But as with any extraordinary claim, extraordinary evidence is needed , and extraordinary caution is warranted.  Here's a different perspective:
https://bigthink.com/starts-with-a-bang/no-warp-bubble/

That would be better if it didn’t come across as such an over emotive article.
« Last Edit: 12/09/2021 04:19 pm by Star One »

Offline Argonaut

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Re: Alcubierre drive - Updates and Discussion
« Reply #261 on: 01/09/2022 05:25 pm »
Quote
Hyper-Fast Positive Energy Warp Drives
Erik W. Lentz

Solitons in space-time capable of transporting time-like observers at superluminal speeds have long been tied to violations of the weak, strong, and dominant energy conditions of general relativity. This trend was recently broken by a new approach that identified Soliton solutions capable of superluminal travel while being sourced by purely positive energy densities. This is the first example of hyper-fast Solitons satisfying the weak energy condition, reopening the discussion of superluminal mechanisms rooted in conventional physics. This article summarizes the recent finding and its context in the literature. Remaining challenges to autonomous superluminal travel, such as the dominant energy condition, horizons, and the identification of a creation mechanism are also discussed.
https://arxiv.org/abs/2201.00652

Quote
The most glaring challenge is the astronomical energy cost of even a modest
warp drive, currently measured in solar masses where kilograms is closer to the
threshold of human technology. Extreme energy savings is going to be necessary –
tens of orders of magnitude – to bring the energy required for a warp drive down
to a level that can be tested in a laboratory setting let alone be considered a viable
transportation technology.
There exist numerous techniques for reducing the energy requirements of the
Alcubierre solution, several of which have been very successful in reducing the
(magnitude) energy requirements of the system in excess of thirty orders of magnitude.
Unfortunately, each one of these methods in their presented forms
require negative energies themselves. One possible approach to uncovering significant
energy savings is to modify one of these existing techniques to obey the WEC.
If the required energy can be sufficiently reduced, the next hurdle to approach is
modeling the full life cycle of a physical warp drive (creation, acceleration, inertial
motion, deceleration, and diffusion). Every previous publication in the field of warp
drives has either assumed inertial motion (constant velocity) or has produced an
accelerating/decelerating drive that violates the law of covariant conservation of
stress-energy-momentum that accompanies the Einstein equation

Good synopsis, lots of citations to follow.

Offline Monomorphic

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Re: Alcubierre drive - Updates and Discussion
« Reply #262 on: 01/15/2022 03:05 pm »

Offline dgwatson5

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Re: Alcubierre drive - Updates and Discussion
« Reply #263 on: 09/02/2022 03:38 pm »
I've written a small 'paper' on a concept about warp drives. I'm attaching it and posting the text below. Let me know what you think.

Warp Drive Starships
The Soap Boats of Space Travel

Space travel is not feasible without being able to travel faster than the cosmic speed limit we commonly refer to as the speed of light. All kinds of sci-fi concepts have been come up with to deal with circumventing this speed limit. None more fascinating to many than the Star Trek styled warp drive. This warp drive allows the various captains of the Star Trek universe to skip across the galaxy exploring.

What if I told you that a real warp drive would likely be like powering an ocean-going ship with soap. This would make Figure 1 analogous to Figure 2. (Figures 1 & 2 are pictures of NCC 1701D Enterprise from Star Trek TNG & a soap boat)
In case any of you have never seen a soap boat or don’t remember the experiment in junior high science class, a soap boat is propelled by a piece of soap placed at the rear of the boat. In the case of Figure 2, it would be placed, touching the water, in the V shaped notch in its stern. This particular design is made this way so that one could use liquid soap such as Dawn dish liquid.
Soap boats work because soap breaks the surface tension at the stern of the boat. This lack of surface tension at the stern allows the surface tension of the water around the sides and at the bow to draw the boat forward. Here is a link with further explanation – Soap-Powered Boat.

You might be asking, “What does this have to do with space and space travel?” Well, it turns out space-time has a certain ‘surface tension’ as well. Nick Lucid on his YouTube channel The Science Asylum has a video that touches on this while explaining how time may cause gravity. You can go here to see that video – The Real Source of Gravity Might Surprise You. PBS Space Time also has a video talking on this subject called ‘Does Time Cause Gravity’.

The portion of what they discuss that I am alluding to is that due to the ‘surface tension’ of space-time, space-time’s temporal flow slows bending inward toward mass just as water’s flow in a river will slow and bend inward toward a large rock or island.

A real warp drive need only do to space time what a ‘soap drive’ does for a soap boat. A warp drive needs to break or reduce the surface tension of space time at the stern of the starship and let the surface tension at the bow and around it to draw the starship forward. I believe we see this in action in the universe and the soap of the universe seems to be theoretical dark energy.

Theoretically dark energy seems to break the surface tension of space-time. In doing so it causes the expansion of the universe in such a way that many distant portions of our universe are moving away from us, and us away from them, at rates greater than the cosmic speed limit.

I believe one can see where I’m going with this. A real warp drive would need to be able to generate or collect enough dark energy and concentrate it at the rear of the starship thus causing the ship to be drawn forward by the ‘surface tension’ of space-time at a rate proportional to the amount of dark energy available.

« Last Edit: 09/02/2022 04:09 pm by dgwatson5 »

Offline SpaceCadet1980

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Re: Alcubierre drive - Updates and Discussion
« Reply #264 on: 09/07/2022 07:35 pm »
A real warp drive need only do to space time what a ‘soap drive’ does for a soap boat. A warp drive needs to break or reduce the surface tension of space time at the stern of the starship and let the surface tension at the bow and around it to draw the starship forward. I believe we see this in action in the universe and the soap of the universe seems to be theoretical dark energy.

Theoretically dark energy seems to break the surface tension of space-time. In doing so it causes the expansion of the universe in such a way that many distant portions of our universe are moving away from us, and us away from them, at rates greater than the cosmic speed limit.

I believe one can see where I’m going with this. A real warp drive would need to be able to generate or collect enough dark energy and concentrate it at the rear of the starship thus causing the ship to be drawn forward by the ‘surface tension’ of space-time at a rate proportional to the amount of dark energy available.
I cut out most of this quote for brevity and because it isn't relevant. A "soap drive" is simply not a good analogy for anything in GR, and those videos you linked are attempts at describing GR to a relatively inexperienced audience. That means they may use analogies that are of only limited general utility to communicate concepts that can only be accurately described with advanced math. It is clear that you misunderstood something from them.

Dark energy does nothing like what you claim. It also as far as we know is simply a fundamental constant and property of the universe. By this definition it is not an actual physical thing that you can collect or manipulate. Nothing in what you are describing here has anything to do with an Alcubierre drive (the subject of this thread) nor does it have anything to do with actual GR in general other than the videos you linked.

Offline Star One

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Alcubierre drive - Updates and Discussion
« Reply #265 on: 08/01/2023 11:07 pm »
New video from Cool Worlds -What’s Stopping Us From Building A Warp Drive:

« Last Edit: 08/01/2023 11:08 pm by Star One »

Offline WarpTech

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Re: Alcubierre drive - Updates and Discussion
« Reply #266 on: 09/20/2023 01:52 pm »
New video's coming... Please subscribe.


Offline Suzy

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Re: Alcubierre drive - Updates and Discussion
« Reply #267 on: 10/11/2023 01:47 am »
Article: "Warp drive's best hope dies, as antimatter falls down," Big Think, 3/10/2023. Alcubierre drive relegated to fantasy.

Quote
Key takeaways: In order to make a working "warp drive," there must be some way to not only curve the fabric of space, but to curve it in fundamentally different directions ahead of and behind the spacecraft. By creating a positively curved region "contracting" the space in front of a spacecraft and a negatively curved region "rarefying" it behind, a "warp bubble" could be created. However, that would require negative mass/energy, and negatively-gravitating antimatter could have done it. Unfortunately, physics said otherwise: antimatter falls down.

Online 93143

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Re: Alcubierre drive - Updates and Discussion
« Reply #268 on: 10/12/2023 06:12 am »
Antimatter having negative mass was always a long shot, and no one was pinning their hopes on it.  In any case the original Alcubierre metric was hilariously implausible even if antimatter had turned out to have negative gravitational mass.  The field has developed since 1994, and more promising directions have started to open up, including classes of metrics that appear to not need negative energy at all.

I just hope Sonny White wasn't full of it when he said oscillating the field at high frequency "reduces the effective stiffness of spacetime" or whatever it was.  I don't see how any static configuration of broadly human-scale masses, positive or negative, could possibly warp space to a useful degree; there's a reason the static optimization techniques tend to tap out in the planetary mass range.  Alternately, the Woodward effect could offer a way to get large transient negative masses, possibly solving the horizon problem along with the curvature problem, but man does that bare-electron theory sound dangerous to mess with - it could end up giving a whole new meaning to the term "gravity bomb"...
« Last Edit: 10/12/2023 08:47 pm by 93143 »

Offline leovinus

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Re: Alcubierre drive - Updates and Discussion
« Reply #269 on: 10/14/2023 09:06 pm »
Article: "Warp drive's best hope dies, as antimatter falls down," Big Think, 3/10/2023. Alcubierre drive relegated to fantasy.

Quote
Key takeaways: In order to make a working "warp drive," there must be some way to not only curve the fabric of space, but to curve it in fundamentally different directions ahead of and behind the spacecraft. By creating a positively curved region "contracting" the space in front of a spacecraft and a negatively curved region "rarefying" it behind, a "warp bubble" could be created. However, that would require negative mass/energy, and negatively-gravitating antimatter could have done it. Unfortunately, physics said otherwise: antimatter falls down.
Anti-matter falling like normal matter is as expected. See the link below to Prof. Matt Strassler for a contemporary take. The Alcubierre drive seems to require something we laughingly call negative-mass matter but that is purely a hypothetical, Sci-fi concept not to be confused with positrons and electrons.
https://profmattstrassler.com/2023/09/27/about-the-news-that-antimatter-doesnt-fall-up/

Offline zubenelgenubi

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Re: Alcubierre drive - Updates and Discussion
« Reply #270 on: 10/24/2023 11:57 pm »
Moderator:
Split/merged Woodward Effect posts to that thread.
« Last Edit: 10/24/2023 11:58 pm by zubenelgenubi »
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Offline Turgin

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Re: Alcubierre drive - Updates and Discussion
« Reply #271 on: 10/25/2023 10:51 pm »
What would it take to get Anti-Matter to maybe react as a polar opposite of its normal gravity relation?

Could the same effect work the same with Matter?

Being able to use Maxwell's Field Equations to plug in desired values mathematically to chase the correct input MIGHT work...

The single biggest question would be the need to use EMF's, or Electro-Magnetic Fields, to induce the desired changes, and if need be, a back-and-forth field set could effectively suspend Matter and Anti-Matter into prearranged self suspending interacting and non-interacting layers within a gravitic energy assembly.

Basically figuring out how to get Matter and Anti-Matter to meet and interact on a Scientist's terms, or multiple, most likely, would be a serious game changer in the reaction department alone.

I would think this form of energy field assistance for M-AM reactions could also be extremely useful in Fusion reactors as well, given the relatively hard and rare chances of Hydrogen and its isotopes to actually meet and do anything...

Tags: Warp Drive 
 

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