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#3440
by
Peter Lauwer
on 07 Apr, 2017 16:03
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The 2017 NASA Innovative Advanced Concepts (NIAC) portfolio of Phase I concepts
April 6, 2017
NASA Invests in 22 Visionary Exploration Concepts
Mach Effects for In Space Propulsion: Interstellar Mission, Heidi Fearn, Space Studies Institute in Mojave, California
https://www.nasa.gov/press-release/nasa-invests-in-22-visionary-exploration-concepts
NASA NIAC awarded Proposal: Mach Effects for in Space Propulsion: Interstellar Mission
TEAM:
Fearn, Heidi Principal Investigator, California State University, Fullerton
Hudson, Gary Co-I/Institutional Principal Investigator, Space Studies Institute
Eubanks, Thomas Co-I/Science Principal Investigator
Long, Bruce Co-I/Science Principal Investigator
March, Paul Consultant
Rodal, Jose' Co-I/Science Principal Investigator
van Rossum, Nolan Graduate/Undergraduate Student
Woodward, James Consultant
That is great! Congratulations!
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#3441
by
ThatOtherGuy
on 07 Apr, 2017 16:37
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#3442
by
Peter Lauwer
on 07 Apr, 2017 17:47
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#3443
by
X_RaY
on 07 Apr, 2017 17:48
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What about a vanilla biquad?
http://martybugs.net/wireless/biquad/
The field pattern generated from this antenna shape is contraindicated. This is because of there are currents in two opposite directions along the wire and the H field points in in different directions for each loop. TE01p fieldpattern shows E-fields arround the central axis of symmetry..
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#3444
by
SeeShells
on 07 Apr, 2017 18:59
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What about a vanilla biquad?
http://martybugs.net/wireless/biquad/
The field pattern generated from this antenna shape is contraindicated. This is because of there are currents in two opposite directions along the wire and the H field points in in different directions for each loop. TE01p fieldpattern shows E-fields arround the central axis of symmetry..
Dropped in for a bit, and reading your discussions on a Helical driven circular polarized antenna. They are tough to build, although this one isn't as tough, as it comprises straight elements of equal length. It would be interesting to see this is something like monomorphic's TE013 cavity.
Circular Polarization for xpol Yagis
http://dg7ybn.de/Building/xpol.htm
Shell
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#3445
by
ThatOtherGuy
on 07 Apr, 2017 20:35
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Got the point, but then it sounds like a cross yagi may be easier to build than an helyx antenna, but then ... they take up lots of space :\
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#3446
by
Monomorphic
on 07 Apr, 2017 20:57
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I understand that Jamie currently uses a helical antenna. link
I do not currently use a helical antenna. I tried one like what you have pictured, but it was worse at impedance matching than the simple open-ended loop. This is the antenna I am using currently:
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#3447
by
Rodal
on 07 Apr, 2017 21:11
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#3448
by
RotoSequence
on 07 Apr, 2017 21:18
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#3449
by
SeeShells
on 07 Apr, 2017 21:32
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#3450
by
tchernik
on 07 Apr, 2017 21:40
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As a follower of news about anomalous thrust reports for several years (because we are not leaving this rock without some serious overhauls to physics) I'm quite happy and elated to see MET being granted a NIAC award by NASA. Which is a beginning, but also the end of a long route before it.
It has been many years of exhausting work and patience from all the people involved, and it shows that persistence, work and honest scientific inquiry do pay off.
And it shows that the Emdrive, being potentially a more accidentally found version of these (maybe) family of devices, still needs to prove a lot of things more to be in the same category of technical and theoretical plausibility.
But it's coming. There are some really terrific engineers and scientists looking at this now and doing what is right: doing science as it should be, making the experiments and letting the data do the talking.
I wish them the best. Ad Astra!
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#3451
by
spupeng7
on 08 Apr, 2017 01:47
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kinetic Alfvén waves. https://www.nasa.gov/feature/goddard/2017/nasa-observations-reshape-basic-plasma-wave-physics
A New Twist on Relativistic Electron Vortices
"finding that the vortex of a relativistic electron has new features compared to that of its low-speed counterpart. Namely, because spin is directly built into the Dirac equation, there is an intrinsic coupling between the electron’s spin and its orbital angular momentum, and these two quantities are no longer separately conserved. However, a limitation of this early work with relativistic electron vortices was that it entailed expressing the electron wave functions in terms of Bessel functions, which extend to infinity."
http://physics.aps.org/articles/v10/26
...
Properties of the First-order Fermi acceleration in fast magnetic reconnection driven by turbulence in collisional MHD flows
"in some circumstances reconnection can be very fast, with rates which are a substantial fraction of the Alfv´en speed VA. Fast reconnection breaks the magnetic field topology releasing magnetic energy explosively thus explaining the bursty emission, for instance, in solar flares.
Relativistic particles are always observed in connection with these flares suggesting that magnetic reconnection can lead to direct particle acceleration In analogy to diffusive shock acceleration (DSA), in which particles confined between the upstream and downstream flows undergo a first-order Fermi acceleration, de Gouveia dal Pino & Lazarianproposed a similar process occurring within the current sheet where trapped particles bounce back and forth between the converging magnetic fluxes of opposite polarity in the large-scale reconnection region. The particles gyrorotate around a reconnected magnetic field."
https://arxiv.org/pdf/1609.08598.pdf
I think the magnetic re-connection is really just that we have in the initial state a bunch of excited charges all moving in a circular fashion. This creates a magnetic field which is a relativistic velocity dependent electric potential (v*potential lines) cause by charge redistributing it self in the current loop as a relativistic effect. Magnetism is one of the few phenomena where we observe the strength of relativity. We wouldn't have magnetism with out relativity. To create a magnetic field charge must initially be accelerated. The time retarded electric field of accelerated charges (light) induces charges around them to accelerate in the opposite direction as the initial current loop. These are counter currents. A counter-current is naturally repulsed from the initial current when it absorbs energy from it. This effect should repulse local charges in the vicinity of a forming solar flare. (they repel the forming of a change in the magnetic field.)
Some of the charges can't escape because they are trapped in the field lines, but this doesn't mean they can't be induced to move as a counter-current to the charges that are forming the solar flare magnetic loop. The more energy is stored in the charges trapped in the magnetic loop the more counter-current (charges trapped in the loop) generate their own magnetic field in opposition of the existing magnetic field. (imagine two superimposed magnetic fields) Repelling magnetic field lines curl away from each other and want to relax. Superimposing a weaker field trapped inside a strong field appears to weaken the initial field. Giving energy to the weaker field can break the field and allow the charges to escape. When they separate and the charges escape magnetic re-connection occurs and the magnetic fields push away from each other to relax their field lines.
Ultimately I think it is nature opposing any change in the magnetic field -dB/dt=curlE. It's why rail guns and magnetic induction motors work.
Not that it isn't worth looking into. There may be something new to discover. Maybe they are onto something new already.
The notion that fields exist separate from the charge distribution and motions that they are created by, is in my opinion, a miss-understanding of the complex structure of time in which they exist.
I don't think this is anything new, it is just a different interpretation of what Special Relativity says about Maxwell's equations. If you don't agree please say why
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#3452
by
Bob Woods
on 08 Apr, 2017 02:45
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#3453
by
dustinthewind
on 08 Apr, 2017 07:51
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kinetic Alfvén waves. https://www.nasa.gov/feature/goddard/2017/nasa-observations-reshape-basic-plasma-wave-physics
A New Twist on Relativistic Electron Vortices
"finding that the vortex of a relativistic electron has new features compared to that of its low-speed counterpart. Namely, because spin is directly built into the Dirac equation, there is an intrinsic coupling between the electron’s spin and its orbital angular momentum, and these two quantities are no longer separately conserved. However, a limitation of this early work with relativistic electron vortices was that it entailed expressing the electron wave functions in terms of Bessel functions, which extend to infinity."
http://physics.aps.org/articles/v10/26
...
Properties of the First-order Fermi acceleration in fast magnetic reconnection driven by turbulence in collisional MHD flows
"in some circumstances reconnection can be very fast, with rates which are a substantial fraction of the Alfv´en speed VA. Fast reconnection breaks the magnetic field topology releasing magnetic energy explosively thus explaining the bursty emission, for instance, in solar flares.
Relativistic particles are always observed in connection with these flares suggesting that magnetic reconnection can lead to direct particle acceleration In analogy to diffusive shock acceleration (DSA), in which particles confined between the upstream and downstream flows undergo a first-order Fermi acceleration, de Gouveia dal Pino & Lazarianproposed a similar process occurring within the current sheet where trapped particles bounce back and forth between the converging magnetic fluxes of opposite polarity in the large-scale reconnection region. The particles gyrorotate around a reconnected magnetic field."
https://arxiv.org/pdf/1609.08598.pdf
I think the magnetic re-connection is really just that we have in the initial state a bunch of excited charges all moving in a circular fashion. This creates a magnetic field which is a relativistic velocity dependent electric potential (v*potential lines) cause by charge redistributing it self in the current loop as a relativistic effect. Magnetism is one of the few phenomena where we observe the strength of relativity. We wouldn't have magnetism with out relativity. To create a magnetic field charge must initially be accelerated. The time retarded electric field of accelerated charges (light) induces charges around them to accelerate in the opposite direction as the initial current loop. These are counter currents. A counter-current is naturally repulsed from the initial current when it absorbs energy from it. This effect should repulse local charges in the vicinity of a forming solar flare. (they repel the forming of a change in the magnetic field.)
Some of the charges can't escape because they are trapped in the field lines, but this doesn't mean they can't be induced to move as a counter-current to the charges that are forming the solar flare magnetic loop. The more energy is stored in the charges trapped in the magnetic loop the more counter-current (charges trapped in the loop) generate their own magnetic field in opposition of the existing magnetic field. (imagine two superimposed magnetic fields) Repelling magnetic field lines curl away from each other and want to relax. Superimposing a weaker field trapped inside a strong field appears to weaken the initial field. Giving energy to the weaker field can break the field and allow the charges to escape. When they separate and the charges escape magnetic re-connection occurs and the magnetic fields push away from each other to relax their field lines.
Ultimately I think it is nature opposing any change in the magnetic field -dB/dt=curlE. It's why rail guns and magnetic induction motors work.
Not that it isn't worth looking into. There may be something new to discover. Maybe they are onto something new already.
The notion that fields exist separate from the charge distribution and motions that they are created by, is in my opinion, a miss-understanding of the complex structure of time in which they exist.
I don't think this is anything new, it is just a different interpretation of what Special Relativity says about Maxwell's equations. If you don't agree please say why
There is a direct connection to the existence of the field to the previous existence of charges but because of the time retardation some fields can take on an existence that seems separate. Light for instance.
Take a positron and electron and let them accelerate toward each other and annihilate. Light is created from the annihilation or creation of a magnetic field, via the acceleration of the charges. That light carries with it the mass/energy of those 2 charges annihilated, however the field does not exist anymore because of the continued presence of the charges which were annihilated. What in the vacuum exists, which causing it to wave, can induce a wave of mass/energy moving at speed c which previously had zero rest mass/energy/momentum? Maybe something similar to the pairs that were previously annihilated?
Maybe the fields are just the universes way of preserving information/mass/energy/momentum over a distance. Light seems to carry with it the retarded change in the existence of a magnetic field or the acceleration of an electric field. I don't disagree that relativity is involved in Maxwell's equations. I am not sure I am really saying much new, as others before me have surely speculated similarly about even phantom pairs. I just find it therapeutic to organize my thoughts (or find/share inspiration) by sharing with or listening to others in the field. I find it difficult to find others that are interested in the same topics locally.
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#3454
by
ThatOtherGuy
on 08 Apr, 2017 13:37
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#3455
by
ThatOtherGuy
on 08 Apr, 2017 14:18
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I understand that Jamie currently uses a helical antenna. link
I do not currently use a helical antenna. I tried one like what you have pitured, but it was worse at impedance matching than the simple open-ended loop I designed. This is the antenna I am using currently:
Interesting; now, not willing to step into your playground, but... did you consider a "
printed" (board) antenna ?
Otherwise something like
this (adjusted for the working frequency) may fit (I suppose)
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#3456
by
ThatOtherGuy
on 08 Apr, 2017 14:49
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What about a vanilla biquad?
http://martybugs.net/wireless/biquad/
The field pattern generated from this antenna shape is contraindicated. This is because of there are currents in two opposite directions along the wire and the H field points in in different directions for each loop. TE01p fieldpattern shows E-fields arround the central axis of symmetry..
I see, well, mine was just an idea (sometimes you just look at the horizon and think
) at any rate ...
http://www.qsl.net/yu1aw/ANT_VHF/fid24ghz.pdf
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#3457
by
dustinthewind
on 08 Apr, 2017 15:32
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kinetic Alfvén waves. https://www.nasa.gov/feature/goddard/2017/nasa-observations-reshape-basic-plasma-wave-physics
...
...
The notion that fields exist separate from the charge distribution and motions that they are created by, is in my opinion, a miss-understanding of the complex structure of time in which they exist.
I don't think this is anything new, it is just a different interpretation of what Special Relativity says about Maxwell's equations. If you don't agree please say why
There is a direct connection to the existence of the field to the previous existence of charges but because of the time retardation some fields can take on an existence that seems separate. Light for instance.
Take a positron and electron and let them accelerate toward each other and annihilate. Light is created from the annihilation or creation of a magnetic field, via the acceleration of the charges. That light carries with it the mass/energy of those 2 charges annihilated, however the field does not exist anymore because of the continued presence of the charges which were annihilated. What in the vacuum exists, which causing it to wave, can induce a wave of mass/energy moving at speed c which previously had zero rest mass/energy/momentum? Maybe something similar to the pairs that were previously annihilated?
Maybe the fields are just the universes way of preserving information/mass/energy/momentum over a distance. Light seems to carry with it the retarded change in the existence of a magnetic field or the acceleration of an electric field. I don't disagree that relativity is involved in Maxwell's equations. I am not sure I am really saying much new, as others before me have surely speculated similarly about even phantom pairs. I just find it therapeutic to organize my thoughts (or find/share inspiration) by sharing with or listening to others in the field. I find it difficult to find others that are interested in the same topics locally.
Maybe changes in wavelength of light indicate changes in relative velocity (Doppler effect), so conveyance of energy between different groups of pairs might have such an effect.
Acceleration under gravity also seems to give such a shift in wavelength. I personally think the idea of the geodesic path is just another way of accounting for light being accelerated, but at twice the rate. This being because like objects that go through 4*pi quantum rotations through space+time light may be accelerated at twice the rate of gravity by both space+time. Sort of like passing through an extra dimension.
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#3458
by
graybeardsyseng
on 09 Apr, 2017 12:11
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I understand that Jamie currently uses a helical antenna. link
I do not currently use a helical antenna. I tried one like what you have pictured, but it was worse at impedance matching than the simple open-ended loop. This is the antenna I am using currently:
Helicals can be very challenging to build and tune.
Have you tried one of these?
http://www.wa5vjb.com/products7.html
Similar to the open ended loop. I have found them to tune fairly easily.
Herman
graybeardsyseng
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#3459
by
graybeardsyseng
on 09 Apr, 2017 12:21
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) at any rate ...