Breakthrough Propulsion Physics Program - Revision history

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	The '''Breakthrough Propulsion Physics Project''' ('''BPP''') was a [[research project]] funded by [[NASA]] from 1996 to 2002 to study various proposals for [[Revolutionary technology\|revolutionary]] methods of [[spacecraft propulsion]] that would require breakthroughs in physics before they could be realized.<ref name="millis2005">{{cite journal\|last1=Millis\|first1=Mark G.\|title= Assessing Potential Propulsion Breakthroughs\|journal= Annals of the New York Academy of Sciences\|volume=1065\|pages=441–461\|date=Dec 1, 2005\|url=https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20060000022.pdf\|access-date=8 February 2018\|bibcode=2005NYASA1065..441M\|doi=10.1196/annals.1370.023\|pmid=16510425\|hdl=2060/20060000022\|s2cid=41358855\|hdl-access=free}}</ref><ref name="frontierschapter3">{{cite book\|last1=Davis\|first1=Eric W.\|last2=Gilster\|first2=Paul A.\|editor-first1=Marc G.\|editor-last1=Millis\|title=Frontiers of propulsion science\|chapter=Recent History of Breakthrough Propulsion Studies\|date=2009\|publisher=American Institute of Aeronautics and Astronautics\|location=Reston, Va.\|isbn=~~9781615830770~~}}</ref> The project ended in 2002, when the Advanced Space Transportation Program was reorganized and all speculative research (less than [[Technology readiness level]] 3) was cancelled.<ref name="frontierschapter3"/>		{{Short description\|NASA space propulsion research project}}
			The '''Breakthrough Propulsion Physics Project''' ('''BPP''') was a [[research project]] funded by [[NASA]] from 1996 to 2002 to study various proposals for [[Revolutionary technology\|revolutionary]] methods of [[spacecraft propulsion]] that would require breakthroughs in physics before they could be realized.<ref name="millis2005">{{cite journal\|last1=Millis\|first1=Mark G.\|title= Assessing Potential Propulsion Breakthroughs\|journal= Annals of the New York Academy of Sciences\|volume=1065\|pages=441–461\|date=Dec 1, 2005\|url=https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20060000022.pdf\|access-date=8 February 2018\|bibcode=2005NYASA1065..441M\|doi=10.1196/annals.1370.023\|pmid=16510425\|hdl=2060/20060000022\|s2cid=41358855\|hdl-access=free}}</ref><ref name="frontierschapter3">{{cite book\|last1=Davis\|first1=Eric W.\|last2=Gilster\|first2=Paul A.\|editor-first1=Marc G.\|editor-last1=Millis\|title=Frontiers of propulsion science\|chapter=Recent History of Breakthrough Propulsion Studies\|date=2009\|publisher=American Institute of Aeronautics and Astronautics\|location=Reston, Va.\|isbn=978-1-61583-077-0}}</ref> The project ended in 2002, when the Advanced Space Transportation Program was reorganized and all speculative research (less than [[Technology readiness level]] 3) was cancelled.<ref name="frontierschapter3"/>
	During its six years of operational funding, this program received a total investment of $1.2 million.		During its six years of operational funding, this program received a total investment of $1.2 million.

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	A theoretical examination of additional atomic [[energy levels]] (deep Dirac levels) was carried out. Some states were ruled out, but the problem remains unsolved.<ref name="frontierschapter3" />		A theoretical examination of additional atomic [[energy levels]] (deep Dirac levels) was carried out. Some states were ruled out, but the problem remains unsolved.<ref name="frontierschapter3" />

	Experiments tested [[James F. Woodward\|Woodward]]’s [[Woodward effect\|theory]]<ref>{{cite journal\|last1=Woodward\|first1=James F.\|title=A new experimental approach to Mach's principle and relativistic graviation\|journal=Foundations of Physics Letters\|date=October 1990\|volume=3\|issue=5\|pages=497–506\|doi=10.1007/BF00665932\|bibcode=1990FoPhL...3..497W\|s2cid=120603211}}</ref><ref>{{cite journal\|last1=Woodward\|first1=James F.\|title=Measurements of a Machian transient mass fluctuation\|journal=Foundations of Physics Letters\|date=October 1991\|volume=4\|issue=5\|pages=407–423\|doi=10.1007/BF00691187\|bibcode=1991FoPhL...4..407W\|s2cid=121750654}}</ref> of inducing transient inertia by electromagnetic fields. The small effect could not be confirmed. Woodward continued refining the experiments and theory. Independent experiments<ref>{{cite journal\|last1=Cramer\|first1=John\|last2=Cassisi\|first2=Damon\|last3=Fey\|first3=Curran\|title=Tests of Mach's Principle with a mechanical oscillator\|journal=37th Joint Propulsion Conference and Exhibit\|date=Oct 1, 2004\|doi=10.2514/6.2001-3908\|url=https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20050080680.pdf\|hdl=2060/20050080680\|s2cid=55948442 \|hdl-access=free}}</ref> also remained inconclusive.<ref name="millis2005" /><ref name="frontierschapter3" />		Experiments tested [[James F. Woodward\|Woodward]]'s [[Woodward effect\|theory]]<ref>{{cite journal\|last1=Woodward\|first1=James F.\|title=A new experimental approach to Mach's principle and relativistic graviation\|journal=Foundations of Physics Letters\|date=October 1990\|volume=3\|issue=5\|pages=497–506\|doi=10.1007/BF00665932\|bibcode=1990FoPhL...3..497W\|s2cid=120603211}}</ref><ref>{{cite journal\|last1=Woodward\|first1=James F.\|title=Measurements of a Machian transient mass fluctuation\|journal=Foundations of Physics Letters\|date=October 1991\|volume=4\|issue=5\|pages=407–423\|doi=10.1007/BF00691187\|bibcode=1991FoPhL...4..407W\|s2cid=121750654}}</ref> of inducing transient inertia by electromagnetic fields. The small effect could not be confirmed. Woodward continued refining the experiments and theory. Independent experiments<ref>{{cite journal\|last1=Cramer\|first1=John\|last2=Cassisi\|first2=Damon\|last3=Fey\|first3=Curran\|title=Tests of Mach's Principle with a mechanical oscillator\|journal=37th Joint Propulsion Conference and Exhibit\|date=Oct 1, 2004\|doi=10.2514/6.2001-3908\|url=https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20050080680.pdf\|hdl=2060/20050080680\|s2cid=55948442 \|hdl-access=free}}</ref> also remained inconclusive.<ref name="millis2005" /><ref name="frontierschapter3" />

	A possible torsion-like effect in the coupling between electromagnetism and spacetime,<ref>{{cite journal\|last1=Ringermacher\|first1=Harry I.\|title=An electrodynamic connection\|journal=Classical and Quantum Gravity\|date=1994\|volume=11\|issue=9\|pages=2383–2394\|doi=10.1088/0264-9381/11/9/018\|language=en\|issn=0264-9381\|bibcode=1994CQGra..11.2383R\|s2cid=250763583 }}</ref> which may ultimately be useful for propulsion, was sought in experiments. The experiments were insufficient to resolve the question.<ref name="frontierschapter3" />		A possible torsion-like effect in the coupling between electromagnetism and spacetime,<ref>{{cite journal\|last1=Ringermacher\|first1=Harry I.\|title=An electrodynamic connection\|journal=Classical and Quantum Gravity\|date=1994\|volume=11\|issue=9\|pages=2383–2394\|doi=10.1088/0264-9381/11/9/018\|language=en\|issn=0264-9381\|bibcode=1994CQGra..11.2383R\|s2cid=250763583 }}</ref> which may ultimately be useful for propulsion, was sought in experiments. The experiments were insufficient to resolve the question.<ref name="frontierschapter3" />
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	The Casimir effect was investigated experimentally and analytically under the Breakthrough Propulsion Physics project. This included the construction of MicroElectroMechanical		The Casimir effect was investigated experimentally and analytically under the Breakthrough Propulsion Physics project. This included the construction of MicroElectroMechanical
	(MEM) rectangular Casimir cavities.<ref name="millis20042" /><ref>{{cite journal\|last1=Maclay\|first1=G. Jordan\|title=Analysis of zero-point electromagnetic energy and Casimir forces in conducting rectangular cavities\|journal=Physical Review A\|date=17 April 2000\|volume=61\|issue=5\|~~pages~~=052110\|doi=10.1103/PhysRevA.61.052110\|bibcode=2000PhRvA..61e2110M}}</ref> Theoretical work showed that the effect could be used to create net forces, although the forces would be extremely small.<ref name="millis2005" /><ref name="millis20042" /><ref>{{cite journal\|last1=Maclay\|first1=G. Jordan\|last2=Forward\|first2=Robert L.\|title=A Gedanken Spacecraft that Operates Using the Quantum Vacuum (Dynamic Casimir Effect)\|journal=Foundations of Physics\|date=March 2004\|volume=34\|issue=3\|pages=477–500\|doi=10.1023/B:FOOP.0000019624.51662.50\|bibcode=2004FoPh...34..477M\|arxiv=physics/0303108\|s2cid=118922542}}</ref> At the conclusion of the project, the Casimir effect was categorized as an avenue for future research.<ref name="millis2005" />		(MEM) rectangular Casimir cavities.<ref name="millis20042" /><ref>{{cite journal\|last1=Maclay\|first1=G. Jordan\|title=Analysis of zero-point electromagnetic energy and Casimir forces in conducting rectangular cavities\|journal=Physical Review A\|date=17 April 2000\|volume=61\|issue=5\|article-number=052110\|doi=10.1103/PhysRevA.61.052110\|bibcode=2000PhRvA..61e2110M}}</ref> Theoretical work showed that the effect could be used to create net forces, although the forces would be extremely small.<ref name="millis2005" /><ref name="millis20042" /><ref>{{cite journal\|last1=Maclay\|first1=G. Jordan\|last2=Forward\|first2=Robert L.\|title=A Gedanken Spacecraft that Operates Using the Quantum Vacuum (Dynamic Casimir Effect)\|journal=Foundations of Physics\|date=March 2004\|volume=34\|issue=3\|pages=477–500\|doi=10.1023/B:FOOP.0000019624.51662.50\|bibcode=2004FoPh...34..477M\|arxiv=physics/0303108\|s2cid=118922542}}</ref> At the conclusion of the project, the Casimir effect was categorized as an avenue for future research.<ref name="millis2005" />

	~~==Tau Zero Foundation==~~

			==Legacy==
	After funding ended, program manager Marc G. Millis was supported by NASA to complete documentation of results. The book ''Frontiers of Propulsion Science'' was published by the [[AIAA]] in February 2009,<ref> M. Millis and E. Davis, ''Frontiers of Propulsion Science'', AIAA, Progress in Astronautics & Aeronautics Vol 227, 2009. {{ISBN\|978-1563479564}}		After funding ended, program manager Marc G. Millis was supported by NASA to complete documentation of results. The book ''Frontiers of Propulsion Science'' was published by the [[AIAA]] in February 2009,<ref> M. Millis and E. Davis, ''Frontiers of Propulsion Science'', AIAA, Progress in Astronautics & Aeronautics Vol 227, 2009. {{ISBN\|978-1563479564}}
	{{ISBN\|1563479567}} </ref> providing a deeper explanation of several propulsion methods.		{{ISBN\|1563479567}} </ref> providing a deeper explanation of several propulsion methods.

	Following program cancellation in 2002, Millis and others founded the Tau Zero Foundation.		===Tau Zero Foundation===
			Following program cancellation in 2002, program manager Marc G. Millis and others, such as Paul Gilster (aerospace chronist and author of the website and book ''Centauri Dreams: Imagining and Planning for Interstellar Flight'', 2004),<ref name="f563">{{cite web \| title=Paul Gilster \| website=Aeon \| url=https://aeon.co/users/paul-gilster \| access-date=November 29, 2025}}</ref> founded the Tau Zero Foundation.<ref name="n979">{{cite web \| title=Paul Gilster \| website=The Planetary Society \| date=March 6, 2015 \| url=https://www.planetary.org/profiles/paul-gilster \| access-date=November 29, 2025}}</ref>

	==See also==		==See also==

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imported>Liz: Removing link(s) to "United States gravity control propulsion research": Removing links to deleted page United States gravity control propulsion research.

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Removing link(s) to "United States gravity control propulsion research": Removing links to deleted page United States gravity control propulsion research.

← Previous revision		Revision as of 16:08, 20 June 2025
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	==See also==		==See also==
	* [[Field propulsion]]		* [[Field propulsion]]
	* [[United States gravity control propulsion research]]		* United States gravity control propulsion research
	* [[Wormhole]]		* [[Wormhole]]

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New page

The '''Breakthrough Propulsion Physics Project''' ('''BPP''') was a [[research project]] funded by [[NASA]] from 1996 to 2002 to study various proposals for [[Revolutionary technology|revolutionary]] methods of [[spacecraft propulsion]] that would require breakthroughs in physics before they could be realized.<ref name="millis2005">{{cite journal|last1=Millis|first1=Mark G.|title= Assessing Potential Propulsion Breakthroughs|journal= Annals of the New York Academy of Sciences|volume=1065|pages=441–461|date=Dec 1, 2005|url=https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20060000022.pdf|access-date=8 February 2018|bibcode=2005NYASA1065..441M|doi=10.1196/annals.1370.023|pmid=16510425|hdl=2060/20060000022|s2cid=41358855|hdl-access=free}}</ref><ref name="frontierschapter3">{{cite book|last1=Davis|first1=Eric W.|last2=Gilster|first2=Paul A.|editor-first1=Marc G.|editor-last1=Millis|title=Frontiers of propulsion science|chapter=Recent History of Breakthrough Propulsion Studies|date=2009|publisher=American Institute of Aeronautics and Astronautics|location=Reston, Va.|isbn=9781615830770}}</ref> The project ended in 2002, when the Advanced Space Transportation Program was reorganized and all speculative research (less than [[Technology readiness level]] 3) was cancelled.<ref name="frontierschapter3"/>
During its six years of operational funding, this program received a total investment of $1.2 million.

The Breakthrough Propulsion Physics project addressed a selection of "incremental and affordable" research questions towards the overall goal of propellantless propulsion, hyperfast travel, and breakthrough propulsion methods.<ref name="millis20042" /> It selected and funded five external projects, two in-house tasks and one
minor grant.<ref name="frontierschapter3"/>
At the end of the project, conclusions into fourteen topics, including these funded projects, were summarized by program manager Marc G. Millis.<ref name="millis2005" /> Of these, six research avenues were found to be nonviable, four were identified as opportunities for continued research, and four remain unresolved.<ref name="millis2005" /><ref name="millis20042">{{cite journal|last1=Millis|first1=Mark G.|date=2004|title=Prospects for Breakthrough Propulsion From Physics|url=https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20040070788.pdf|access-date=8 February 2018}}</ref>

==Non-viable approaches==
One in-house experiment tested the Schlicher thruster antenna, claimed by Schlicher<ref>{{cite journal|last1=Schlicher|first1=R|last2=Biggs|first2=A|last3=Tedeschi|first3=W|title=Mechanical propulsion from unsymmetrical magnetic induction fields|journal=31st Joint Propulsion Conference and Exhibit|page=2643|doi=10.2514/6.1995-2643|year=1995}}</ref> to generate thrust. No thrust was observed.<ref name="frontierschapter3" /><ref>{{cite journal|last1=Fralick|first1=Gustave|last2=Niedra|first2=Janis|title=Experimental results of Schlicher's thrusting antenna|journal=37th Joint Propulsion Conference and Exhibit|date=Nov 1, 2001|doi=10.2514/6.2001-3657|url=https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20020009088.pdf|hdl=2060/20020009088|hdl-access=free}}</ref>

Another experiment examined a gravity shielding mechanism claimed by Podkletnov and Nieminen.<ref name="frontierschapter3" /><ref>{{cite journal|last1=Podkletnov|first1=E.|last2=Nieminen|first2=R.|title=A possibility of gravitational force shielding by bulk YBa2Cu3O7−x superconductor|journal=Physica C: Superconductivity|date=December 1992|volume=203|issue=3–4|pages=441–444|doi=10.1016/0921-4534(92)90055-H|bibcode=1992PhyC..203..441P}}</ref> Experimental investigation on the BPPP<ref>{{cite journal|last1=Robertson|first1=Tony|last2=Lichford|first2=Ron|last3=Peters|first3=Randall|last4=Thompson|first4=Byran|last5=Rogers|first5=Stephen L.|title=Exploration of Anomalous Gravity Effects by rf-Pumped Magnetized High-T(c) Superconducting Oxides|journal=AIAA Joint Propulsion Conference; 8-11 Jul. 2001; Salt Lake City, UT; United States|date=Jan 1, 2001|url=https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20020016600.pdf}}</ref> and other experiments<ref>{{cite journal|last1=Hathaway|first1=G|last2=Cleveland|first2=B|last3=Bao|first3=Y|title=Gravity modification experiment using a rotating superconducting disk and radio frequency fields|journal=Physica C: Superconductivity|date=April 2003|volume=385|issue=4|pages=488–500|doi=10.1016/S0921-4534(02)02284-0|bibcode=2003PhyC..385..488H}}</ref> found no evidence of the effect.<ref name="millis2005" />

Research on quantum tunneling was sponsored by the BPPP. It was concluded that this is not a mechanism for faster-than-light travel.<ref name="millis2005" /><ref name="frontierschapter3" />

Other approaches categorized as non-viable are oscillation thrusters and gyroscopic antigravity, Hooper antigravity coils, and coronal blowers.<ref name="millis2005" />

==Unresolved approaches==
A theoretical examination of additional atomic [[energy levels]] (deep Dirac levels) was carried out. Some states were ruled out, but the problem remains unsolved.<ref name="frontierschapter3" />

Experiments tested [[James F. Woodward|Woodward]]’s [[Woodward effect|theory]]<ref>{{cite journal|last1=Woodward|first1=James F.|title=A new experimental approach to Mach's principle and relativistic graviation|journal=Foundations of Physics Letters|date=October 1990|volume=3|issue=5|pages=497–506|doi=10.1007/BF00665932|bibcode=1990FoPhL...3..497W|s2cid=120603211}}</ref><ref>{{cite journal|last1=Woodward|first1=James F.|title=Measurements of a Machian transient mass fluctuation|journal=Foundations of Physics Letters|date=October 1991|volume=4|issue=5|pages=407–423|doi=10.1007/BF00691187|bibcode=1991FoPhL...4..407W|s2cid=121750654}}</ref> of inducing transient inertia by electromagnetic fields. The small effect could not be confirmed. Woodward continued refining the experiments and theory. Independent experiments<ref>{{cite journal|last1=Cramer|first1=John|last2=Cassisi|first2=Damon|last3=Fey|first3=Curran|title=Tests of Mach's Principle with a mechanical oscillator|journal=37th Joint Propulsion Conference and Exhibit|date=Oct 1, 2004|doi=10.2514/6.2001-3908|url=https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20050080680.pdf|hdl=2060/20050080680|s2cid=55948442 |hdl-access=free}}</ref> also remained inconclusive.<ref name="millis2005" /><ref name="frontierschapter3" />

A possible torsion-like effect in the coupling between electromagnetism and spacetime,<ref>{{cite journal|last1=Ringermacher|first1=Harry I.|title=An electrodynamic connection|journal=Classical and Quantum Gravity|date=1994|volume=11|issue=9|pages=2383–2394|doi=10.1088/0264-9381/11/9/018|language=en|issn=0264-9381|bibcode=1994CQGra..11.2383R|s2cid=250763583 }}</ref> which may ultimately be useful for propulsion, was sought in experiments. The experiments were insufficient to resolve the question.<ref name="frontierschapter3" />

Other theories listed in Millis's final assessment as unresolved are [[Abraham-Minkowski controversy|Abraham–Minkowski]] electromagnetic momentum, interpreting inertia and gravity quantum vacuum effects, and the Podkletnov force beam.<ref name="millis2005" />

== Space drives ==
One of the eight tasks funded by the BPP program was to define a strategy towards space drives.<ref name="frontierschapter3" />

As a motivation, seven examples of hypothetical space drives were described at the onset of the project.<ref name="millis2005" /> These included the gravity-based pitch drive, bias drive, disjunction drive and diametric drive; the [[Alcubierre drive]]; and the vacuum energy based differential sail.<ref name="millis1997" />

The project then considered the mechanisms behind these drives. At the end of the project, three mechanisms were identified as areas for future research. One considers the possibility of a reaction mass in seemingly empty space, for example in [[dark matter]], [[dark energy]], or [[zero-point energy]]. Another approach is to reconsider [[Mach's principle]] and [[Euclidean space]]. A third research avenue that might ultimately prove useful for spacecraft propulsion is the [[Coupling (physics)|coupling of fundamental forces]] on sub-atomic scales.<ref name="millis2005" />

== Quantum vacuum energy experiments ==

One topic of investigations was the use of the [[zero-point energy]] field. As the [[Werner Heisenberg|Heisenberg]] [[uncertainty principle]] implies that there is no such thing as an exact amount of energy in an exact location, [[quantum fluctuation|vacuum fluctuation]]s are known to lead to discernible effects such as the [[Casimir effect]]. The differential sail is a speculative drive, based on the possibility of inducing differences in the pressure of vacuum fluctuations on either side of a sail-like structure — with the pressure being somehow reduced on the forward surface of the sail, but pushing as normal on the aft surface — and thus propel a vehicle forward.<ref name="frontierschapter3" /><ref name="millis1997">{{cite journal|last1=Millis|first1=Marc G.|title=Challenge to Create the Space Drive|journal=Journal of Propulsion and Power|date=September 1997|volume=13|issue=5|pages=577–582|doi=10.2514/2.5215|url=https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19990023236.pdf|access-date=8 February 2018|hdl=2060/19980021277|s2cid=3088306 |hdl-access=free}}</ref><ref name="Popular Science">{{cite magazine |url=https://books.google.com/books?id=kP6ESrt1xLUC&q=disjunction+drive&pg=PA50|magazine=Popular Science |title=Space at Warp Speed: Disjunction Drive |page=50 |first=Mariette |last=DiChristina |date=May 2001 |access-date=2012-01-25}}</ref>

The Casimir effect was investigated experimentally and analytically under the Breakthrough Propulsion Physics project. This included the construction of MicroElectroMechanical
(MEM) rectangular Casimir cavities.<ref name="millis20042" /><ref>{{cite journal|last1=Maclay|first1=G. Jordan|title=Analysis of zero-point electromagnetic energy and Casimir forces in conducting rectangular cavities|journal=Physical Review A|date=17 April 2000|volume=61|issue=5|pages=052110|doi=10.1103/PhysRevA.61.052110|bibcode=2000PhRvA..61e2110M}}</ref> Theoretical work showed that the effect could be used to create net forces, although the forces would be extremely small.<ref name="millis2005" /><ref name="millis20042" /><ref>{{cite journal|last1=Maclay|first1=G. Jordan|last2=Forward|first2=Robert L.|title=A Gedanken Spacecraft that Operates Using the Quantum Vacuum (Dynamic Casimir Effect)|journal=Foundations of Physics|date=March 2004|volume=34|issue=3|pages=477–500|doi=10.1023/B:FOOP.0000019624.51662.50|bibcode=2004FoPh...34..477M|arxiv=physics/0303108|s2cid=118922542}}</ref> At the conclusion of the project, the Casimir effect was categorized as an avenue for future research.<ref name="millis2005" />

==Tau Zero Foundation==

After funding ended, program manager Marc G. Millis was supported by NASA to complete documentation of results. The book ''Frontiers of Propulsion Science'' was published by the [[AIAA]] in February 2009,<ref> M. Millis and E. Davis, ''Frontiers of Propulsion Science'', AIAA, Progress in Astronautics & Aeronautics Vol 227, 2009. {{ISBN|978-1563479564}}
{{ISBN|1563479567}} </ref> providing a deeper explanation of several propulsion methods.

Following program cancellation in 2002, Millis and others founded the Tau Zero Foundation.

==See also==
* [[Field propulsion]]
* [[United States gravity control propulsion research]]
* [[Wormhole]]

==References==
{{reflist}}

[[Category:Interstellar travel]]
[[Category:Spacecraft propulsion]]
[[Category:Scientific speculation]]
[[Category:Warp drive theory]]

← Previous revision		Revision as of 18:01, 20 June 2025
Line 47:		Line 47:
	==See also==		==See also==
	* [[Field propulsion]]		* [[Field propulsion]]
	* United States gravity control propulsion research
	* [[Wormhole]]		* [[Wormhole]]