Author Topic: EM Drive Developments - related to space flight applications - Thread 11  (Read 241198 times)

Offline dustinthewind

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Here is an extra that seemed interesting. 
A Theoretical Justification of NASA Electromagnetic
Drive based on Cosmic Dark Matter
Mohamed S. ElNaschie
https://scholar.google.com/scholar?cites=16671618278540492657&as_sdt=5,26&sciodt=0,26&hl=en

I think its based on this papper here:
Completing Einstein’s Spacetime
M. S. El Naschie
https://scholar.google.com/scholar?cluster=2307852642997297549&hl=en&as_sdt=5,26&sciodt=0,26

From a dual Einstein-Kaluza spacetime to 'tHooft renormalon and the reality of accelerated cosmic expansion
MS El Naschie
https://scholar.google.com/scholar?cluster=17151164495508288154&hl=en&as_sdt=5,26&sciodt=0,26

El Naschie is a notorious crackpot.

You appear to be right.  Thanks.  Wasn't sure what to think of his paper but seemed related.  Recommend doing a wiki search on authors I guess. 

Offline oyzw

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我重新设计了一个组合腔体 TM模,Q35000

Offline Bob Woods

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我重新设计了一个组合腔体 TM模,Q35000
I redesigned a combined cavity TM module, Q35000

Offline Ricvil

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我重新设计了一个组合腔体 TM模,Q35000
Beautiful design.
Very simple.
It could be done with a perfect cylinder section, without division of forces with the flat end.
Why do you use (wich appears to be) an almost cylinder ( but not perfect cylinder) section?
PS: As it is a screenshot figure, I can go wrong, and it is a perfect cylinder section.
« Last Edit: 02/03/2019 09:47 am by Ricvil »

Offline Ricvil

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Merging together....
« Last Edit: 02/03/2019 09:29 am by Ricvil »

Online OhYeah

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Your statement that there is no evidence for dark matter is 100% false. I even referenced some of it in my previous post. There is a list of different effects predicted by dark matter theories and observed in experiment in the "Observational Evidence" section of its Wikipedia article. As I mentioned in my last post there is evidence that dark matter distribution is not completely uniform, and that is a difficult set of data to reconcile with any theory that claims that there is no dark matter. (No dark matter anywhere, just modified physics, would be a perfectly uniform distribution by definition.)

Well... that depends on how you define "evidence". We have no direct evidence, but we have a variety of cosmic phenomena that *could* be explained by various dark matter models. These phenomena don't necessarily need  a single explanation and there could be many different processes that produce the effect we currently attribute to dark matter.

I think that alternative theories need to be explored because so far dark matter research has come up with absolutely nothing concrete. I'm sure you are familiar with the research a couple of years ago where they discovered that after looking at 150+ galaxies it seemed that galaxy rotations depend completely on the amount of visible matter only. If I'm not mistaken most physicists hoped to find direct evidence of dark matter with the LHC but so far it has produced no results.

How many more years or decades of dark matter research - and how much money spent - with zero results do we need until people start seriously thinking about alternatives here? My gut feeling (which is worth sod all in the grand scheme of things) says that the key must be in a link that ties GR and QM together in some form.

Offline meberbs

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Well... that depends on how you define "evidence". We have no direct evidence, but we have a variety of cosmic phenomena that *could* be explained by various dark matter models. These phenomena don't necessarily need  a single explanation and there could be many different processes that produce the effect we currently attribute to dark matter.
This is getting off topic, and your post is mostly addressed by information I provided in previous posts, but I will try to restate it one more time.

"Observational Evidence" is the title of the Wikipedia section I referenced. In other words that is evidence. You seem to be implying that "direct evidence" would be a laboratory experiment where you can observe dark matter directly, which is not necessarily even possible since dark matter appears to only interact through gravitational force. In this case the only way to have direct evidence of it is by measuring its gravitational effects which scientists have done. (See the "gravitational lensing" subsection in the Wikipedia article.)

I think that alternative theories need to be explored because so far dark matter research has come up with absolutely nothing concrete. I'm sure you are familiar with the research a couple of years ago where they discovered that after looking at 150+ galaxies it seemed that galaxy rotations depend completely on the amount of visible matter only. If I'm not mistaken most physicists hoped to find direct evidence of dark matter with the LHC but so far it has produced no results.
Alternative theories have been explored, but none of them really fit all of the data.
https://xkcd.com/1758/
I don't read every paper that comes out on this subject, so I haven't read the one you referenced, but I am aware that most galaxies have close to the same ratio of matter and dark matter. That doesn't change the evidence I linked to about outliers with extra or very little dark matter. Outliers are expected to be uncommon and they are. They are still expected to exist and they do.

As for the LHC, you are confusing the terms "hope" and "expect." I was hoping that the LHC would not find the Higgs Boson where it was expected, because that would have had much more interesting consequences. Scientists hoped that the LHC would discover all kinds of completely new things, but for the most part they had little reason to expect it to do so, and for the most part it didn't.

How many more years or decades of dark matter research - and how much money spent - with zero results do we need until people start seriously thinking about alternatives here? My gut feeling (which is worth sod all in the grand scheme of things) says that the key must be in a link that ties GR and QM together in some form.
The answer to your first question is zero years. Scientists have been working on alternatives to dark matter for as long as there has been evidence to suggest the existence of dark matter. As I already said, none of them really explain the data as well as dark matter does. The recent evidence that I linked to, as well as various other details make it seem increasingly unlikely that any theory will work out that doesn't contain at least some form of dark matter.

As for a link between GR and QM, that has been an area of research for as long as both of those theories have existed. There are many difficulties with doing that, and there are a variety of theories that attempt to make it work. The biggest problem is that the relevant regimes to test them are generally well beyond current technology. At this point though, such things may be helpful for explaining dark energy, but probably won't help much for dark matter, unless they happen to predict new particles that have the expected properties of dark matter.

Offline flux_capacitor

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Interesting article about 96-year old Nobel Prize in Physics Arthur Ashkin and his private lab in his basement. He's still doing research at home!

Ashkin is known for his discoveries in lasers, especially the "laser trap" able to levitate and manipulate very small bodies (like DNA). Now he thinks he will "save the world" bringing "more efficient and cheaper electricity" with an improved technique to funnel and concentrate light down to solar cells or heat transfer fluid pipes.

A recent article on Ashkin and his solar research in Business Insider:
Hilary Brueck (26 Jan 2019): "The world's oldest Nobel Prize winner, a 96-year-old physicist, says his new invention will give everyone in the world clean, cheap energy"

At first, nothing to do with the EmDrive. But let's have a look at Ashkin's patents, in particular this one:
Ashkin, Arthur: "Compound collector system for solar energy concentration". US Patent 8960185B2. Filed: December 13, 2011. Granted: February 24, 2015.
PDF version attached below.

Excerpts (emphasis added):

ABSTRACT: A solar collector is formed as a compound arrangement of a multiple number of tapered, pyramidal-type structures. This forms an N-stage solar collector, each stage providing a degree of concentration and thus forming an arrangement that is smaller than a single stage collector (while achieving the same amplification factor). The stages are arranged in tandem along a common optical axis, with the output of the first stage becoming the input for the second stage, and so on. It was found that a reduced number of reflections is required, reducing the loss of the overall system.

FIG. 1(a) shows a right-angled, truncated pyramidal solar collector formed in accordance with the present invention, having a square geometry input and output face:



FIG. 1(b) is a variation of the collector of FIG. 1(a), in this case being of conic form with a circular geometry input and output face:



FIG. 2 is a cut-away side view of the collector of FIGS. 1(a) and (b), taken along collector axis CA:



FIG. 3 is a master diagram derived from the geometry of the solar collector of FIG. 1(a):



FIG. 4(a) contains a diagram showing the paths of various solar rays propagating through the collector of FIG. 1(a):



FIG. 5 shows the resulting image from the collector of FIG. 1(a), generating a Buckminster-Fullerene-type solar radiation pattern as produced by a single stage solar collector of the present invention. Entering parallel rays that strike the inner Buckminster-Fullerene “sphere” all pass through the output face and are utilized. Entering rays that miss the sphere are all retro-reflected. This aspect of pyramidal collectors provides a useful way of evaluating the performance of the overall collector system:



FIG. 12(a) is a side view of an exemplary ziggurat-like support structure for use with a square-based truncated pyramidal solar collector, such as shown in FIG. 1(a), where FIG. 12(b) is an experimental model of the arrangement o FIG. 12(a), as seen from the collector entrance:



FIG. 13 shows different truncated pyramidal geometries which may be used to form solar collectors in accordance with the present invention:



FIG. 14 depicts the Buckminster-Fullerene type images associated with the solar collector geometries of FIG. 13:


 
FIG. 17 illustrates an exemplary collector array, as held within a framework, in this case supporting a 4×5 array of compound collectors formed in accordance with the present invention:





Obviously, I admit that aside the shape, the possible relation with RF resonant cavities is loose, especially as such system does not use microwaves but light; and more than anything it is not a resonator (no EM modes). Therefore this post may appear almost off-topic, my apologies for that.

Still, FIGs 2 and 12(b) are quite reminiscent of Shawyer's first schemes about the EmDrive. More interesting perhaps, I wonder if Ashkin's findings, especially shown in FIG. 12(b), could be linked to Travis S. Taylor's research in the optical (laser-based) EmDrive, especially about the length to small diameter ratio (S/D) in FIGs 2 and 3, which reminds me of Shawer's "design factor" and "cut-off condition" as well as McCulloch's optimal aspect ratio according to his theory of quantized inertia.

Anyway, I found this "Buckminster-Fullerene-type solar radiation pattern" interesting. This may not be a kaleidoscope thruster at all, but it is entertaining. And after the recent EmDrive debacle, it may prove that frustums can have a real application in physics, finally… ;D

Offline Ricvil

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Just another sugestion (more simple) to concentrate the radiation pressure in the middle of cavity, version 2.
A mixing of Shawyer and Oyzw designs.

PS: Sorry, there is a fatal error in this design.
It's happening because it is a free hand drawing, and the design needs precision.
A small adjust is necessary.
PS2: Corrected design added.
« Last Edit: 02/12/2019 11:49 am by Ricvil »

Offline flux_capacitor

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As I mentioned in my last post there is evidence that dark matter distribution is not completely uniform

That observation was indeed weird, not only by the findings themselves, but also due to its uniqueness. At that time, it could have been the beginning of a series of similar observations, later confirmed. But it didn't turn out that way, and the "evidence" has recently evaporated. NGC 1052-DF2 seems to be a normal galaxy (i.e. equally confined by a dark matter halo) after all: "Later studies have failed to confirm the lack of dark matter, and shown only that it is likely to have a mass-to-light ratio towards the low end of expected values for a dwarf galaxy."

Anyway, recent large-scale surveys (like KiDS) tend to prove that dark matter distribution is even more uniform and smoother than thought initially.

Which implies that the lambda-CDM model cannot explain, with such an even distribution of DM across the galaxy, smaller scale anomalous behaviors like globular clusters and wide binaries anomalies, for example.

The chapter "Gravitational Anomalies Signaling the Breakdown of Classical Gravity" in the book "Accelerated Cosmic Expansion" (Springer 2014) exposes this problem well. Attached below for reference.
« Last Edit: 02/10/2019 01:56 pm by flux_capacitor »

Offline meberbs

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As I mentioned in my last post there is evidence that dark matter distribution is not completely uniform

That observation was indeed weird, not only by the findings themselves, but also due to its uniqueness. At that time, it could have been the beginning of a series of similar observations, later confirmed. But it didn't turn out that way, and the "evidence" has recently evaporated. NGC 1052-DF2 seems to be a normal galaxy (i.e. equally confined by a dark matter halo) after all: "Later studies have failed to confirm the lack of dark matter, and shown only that it is likely to have a mass-to-light ratio towards the low end of expected values for a dwarf galaxy."
Every last statement in that paragraph is false. Even the quote is misrepresented by you. That is a quote from Wikipedia. (The sentence from Wikipedia has been corrected now for consistency with what the (singular) referenced paper says.)

The article I linked references more than one piece of evidence to my point, so it appears you did not read the whole thing. It has been something like a year since the initial results on the low dark matter content got reported. It takes time for astronomers to look through data and acquire new data. It also takes time to get results published. A lack of additional finds in one year means literally nothing. The paper you cite in "contradiction" actually is basically saying that the error bars are a bit wider. Note that the part you quote states "towards the low end." In other words even after widening the error bars, it still shows a different ratio than the average for its class, which still supports the point.

Anyway, recent large-scale surveys (like KiDS) tend to prove that dark matter distribution is even more uniform and smoother than thought initially.

Which implies that the lambda-CDM model cannot explain, with such an even distribution of DM across the galaxy, smaller scale anomalous behaviors like globular clusters and wide binaries anomalies, for example.
The first result you link to is showing disagreement with a previous experiment, not disagreement with theory. It may change some parameters in theory that had been based on the previous result, but there is no evidence to support your claim that the new data is completely incompatible with the models.

The next 2 papers just are evidence of what I already said: scientists have been considering alternatives to dark matter such as MOND, and claims from poster like OhYeah to the contrary are completely false.

The chapter "Gravitational Anomalies Signaling the Breakdown of Classical Gravity" in the book "Accelerated Cosmic Expansion" (Springer 2014) exposes this problem well. Attached below for reference.
Something written in 2014 does not address results from years after it was written. Also, it claims to find problems with GR that can't be explained by GR, but the only one that seems to be a real potential issue is the bullet cluster, which has since been shown to be explained just fine by ΛCDM models. I honestly don't like how it is written, since it seems to jump between "this can't be explained by GR (without dark matter)" and make it sound like it still wouldn't be explained with dark matter. It also generally ignores the fact that there are problems with MOND. A basic list can be found on Wikipedia.

Offline Ricvil

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Corrected design for radiation pressure localized at the central part of cavity, showing expected oyzw and Shawyer regions of attenuated fields, one at each end(dotted lines showing the separation).

Offline Star One

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This article seems relevant to this thread.

2019 Symposium Call for Papers

Quote
In collaboration with the National Aeronautics and Space Administration (NASA), the Tennessee Valley Interstellar Workshop (TVIW) hereby invites participation in its 6th Interstellar Symposium and Interstellar Propulsion Workshop -hosted by Wichita State University (WSU) and Ad Astra Kansas Foundation – to be held from Sunday, November 10 through Friday, November 15, 2019, in Wichita, Kansas. The 2019 TVIW has the following elements:

The NASA Workshop on Interstellar Propulsion will focus solely on physics-based propulsion technologies that have the potential to meet the goal of launching an interstellar probe within the next century and achieving .1c transit velocity: Beamed Energy Propulsion, Fusion, and Antimatter.

At this meeting, the state-of-the-art of each will be examined, competing approaches to advancing the Technology Readiness Level (TRL) of each will be presented by advocates and assessed by non-advocates for synthesis into a workshop report to serve as the blueprint for possible future interstellar propulsion technology development.


Offline meberbs

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Corrected design for radiation pressure localized at the central part of cavity, showing expected oyzw and Shawyer regions of attenuated fields, one at each end(dotted lines showing the separation).
First, I believe the term that you are looking for is "field strength" or roughly equivalently "electromagnetic energy density." Radiation pressure by definition requires a surface that pressure is being applied to.

Second, drawing a bunch of equally spaced circles has nothing to do with where the fields would be. The fields are in the locations that the laws of electrodynamics say they will be for a given frequency given the boundary conditions defined by the metal walls of the cavity.

I am curious where you got the idea that drawing a bunch of circles on top of a picture of a cavity would have any relation to the electromagnetic fields at all.

Offline X_RaY

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Corrected design for radiation pressure localized at the central part of cavity, showing expected oyzw and Shawyer regions of attenuated fields, one at each end(dotted lines showing the separation).
It seems that you have put some work into it and you think that it might be of interest to the public. There is, however, a considerable lack of explaining what you mean and what you have outlined. So, what does it mean what you show and what do you think about the possible net thrust of such a system? Where in your 'model' comes the thrust from? (I am aware of your previous 'explanations'.)

EDIT
Thank's meberbs,
you came up with your quote just before mine. You put my thoughts into words in a similar way.
« Last Edit: 02/12/2019 09:23 pm by X_RaY »

Offline Monomorphic

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This article seems relevant to this thread.

2019 Symposium Call for Papers

Quote
In collaboration with the National Aeronautics and Space Administration (NASA), the Tennessee Valley Interstellar Workshop (TVIW) hereby invites participation in its 6th Interstellar Symposium and Interstellar Propulsion Workshop -hosted by Wichita State University (WSU) and Ad Astra Kansas Foundation – to be held from Sunday, November 10 through Friday, November 15, 2019, in Wichita, Kansas. The 2019 TVIW has the following elements:

The NASA Workshop on Interstellar Propulsion will focus solely on physics-based propulsion technologies that have the potential to meet the goal of launching an interstellar probe within the next century and achieving .1c transit velocity: Beamed Energy Propulsion, Fusion, and Antimatter.

At this meeting, the state-of-the-art of each will be examined, competing approaches to advancing the Technology Readiness Level (TRL) of each will be presented by advocates and assessed by non-advocates for synthesis into a workshop report to serve as the blueprint for possible future interstellar propulsion technology development.

It is relevant in that NASA seems to have now excluded so-called "advanced propulsion" in favor of "physics-based" propulsion technologies such as Beamed Energy Propulsion, Fusion, and Antimatter. 

No Emdrive. No Mach Effect. No Quantized Inertia.
« Last Edit: 02/13/2019 12:34 am by Monomorphic »

Offline Ricvil

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Corrected design for radiation pressure localized at the central part of cavity, showing expected oyzw and Shawyer regions of attenuated fields, one at each end(dotted lines showing the separation).
It seems that you have put some work into it and you think that it might be of interest to the public. There is, however, a considerable lack of explaining what you mean and what you have outlined. So, what does it mean what you show and what do you think about the possible net thrust of such a system? Where in your 'model' comes the thrust from? (I am aware of your previous 'explanations'.)

EDIT
Thank's meberbs,
you came up with your quote just before mine. You put my thoughts into words in a similar way.

Dear Meberbs and X_RaY.
The "circles" and straight lines, are in fact, spheres, planes and conical surfaces under rotation around the axis of symmetry. Their intersections, are the most easy way to define the geometry of the cavity on any scale.
When in chinese (by internet translator), oyzw named it's cavity as "bouquet cavity", the geometry with all this "circles" becomes clear to me.
But I not see any questions directed about the "bouquet cavity".
I've worked with inverse scattering problems, many time  ago, doing continuation of free space electromagnetic fields, using bessel functions expansions, around metalic surfaces, in frequency domain.
Curiously, I've already observed these abrupt transitions of electromagnetic fields intensity as caustic around metalic surfaces.
There are conformal symmetries, for both space time and electromagnetic fields, and I just exploring an empirical one, as a guidind for aproximation.
The final result depends of simulation, or experimentation.
You're already understood the result presented by oyzw?
Are you using Shawyer "cutoff rules" ?
I'm using a "inverse surface intrinsic curvature signal change", from my observation of results presented in this forum.
My cavity design is just a sugestion.
They will produce thrust if almost field strenght of a TE/TM mode is restricted only at central conical section of cavity, and if at the flat ends the field strenght becomes very attenuated.

Offline meberbs

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The "circles" and straight lines, are in fact, spheres, planes and conical surfaces under rotation around the axis of symmetry. Their intersections, are the most easy way to define the geometry of the cavity on any scale.
Are you saying that all the circles represent metal surfaces that would actually be built? I assume the answer is no, because that would just create a bunch of separate small cavities, and have no sensible use.

If they are just there to illustrate the relative dimensions of the cavity, then the question is why are those dimensions special, and why do you think they would cause the electromagnetic energy to be concentrated in the center of the cavity? Based on seeing lots of field patterns in these threads over the years, and understanding the physics behind them, I doubt that the cavity you drew has any mode that would behave inthe manner you describe.

When in chinese (by internet translator), oyzw named it's cavity as "bouquet cavity", the geometry with all this "circles" becomes clear to me.

But I not see any questions directed about the "bouquet cavity".
I don't recall any post from oyzw that mentions a "bouquet cavity," so I don't know what you are talking about, maybe you got a bad translation for some reason.

You're already understood the result presented by oyzw?
He presented a field pattern result for a specific cavity shape. It looks reasonable, but has no provided reason why that design should be expected to produce useful thrust versus all of the other designs that people have proposed or tried.

Are you using Shawyer "cutoff rules" ?
No. Shawyer's discussion about "cutoff" is mostly nonsensical, though it does give a rule of thumb for predicting some aspects of what a mode shape will look like in certain cases.

They will produce thrust if almost field strenght of a TE/TM mode is restricted only at central conical section of cavity, and if at the flat ends the field strenght becomes very attenuated.
First, I do not believe a mode shape like you described can exist in anything even close to the cavities that people have been working with. Especially not the design you provided, since with the constant diameter near the small end, the field would not particularly attenuate towards the small end as oyzw's result showed. Second, there is no reason to expect concentrating the field in the center of the cavity to somehow allow the drive to violate conservation of momentum.

Offline Star One

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This article seems relevant to this thread.

2019 Symposium Call for Papers

Quote
In collaboration with the National Aeronautics and Space Administration (NASA), the Tennessee Valley Interstellar Workshop (TVIW) hereby invites participation in its 6th Interstellar Symposium and Interstellar Propulsion Workshop -hosted by Wichita State University (WSU) and Ad Astra Kansas Foundation – to be held from Sunday, November 10 through Friday, November 15, 2019, in Wichita, Kansas. The 2019 TVIW has the following elements:

The NASA Workshop on Interstellar Propulsion will focus solely on physics-based propulsion technologies that have the potential to meet the goal of launching an interstellar probe within the next century and achieving .1c transit velocity: Beamed Energy Propulsion, Fusion, and Antimatter.

At this meeting, the state-of-the-art of each will be examined, competing approaches to advancing the Technology Readiness Level (TRL) of each will be presented by advocates and assessed by non-advocates for synthesis into a workshop report to serve as the blueprint for possible future interstellar propulsion technology development.

It is relevant in that NASA seems to have now excluded so-called "advanced propulsion" in favor of "physics-based" propulsion technologies such as Beamed Energy Propulsion, Fusion, and Antimatter. 

No Emdrive. No Mach Effect. No Quantized Inertia.

Do you blame them?

Offline Bob Woods

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It is relevant in that NASA seems to have now excluded so-called "advanced propulsion" in favor of "physics-based" propulsion technologies such as Beamed Energy Propulsion, Fusion, and Antimatter. 

No Emdrive. No Mach Effect. No Quantized Inertia.

Monomorphic did excellent work showing deficiencies in the test and measurement systems. That's what science is about, and he did an admirable job.

But... it would be nice if new avenues could be discovered to develop a workable and provable "propellantless" drive. That's also what science is, and would also be an admirable job.
« Last Edit: 02/13/2019 07:04 am by Bob Woods »

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