Bubble fusion

Bubble fusion, also known as sonofusion, is the non-technical name for a nuclear fusion reaction hypothesized to occur during sonoluminescence, an extreme form of acoustic cavitation. Officially, this reaction is termed acoustic inertial confinement fusion (AICF) since the inertia of the collapsing bubble wall confines the energy, causing an extreme rise in temperature. The high temperatures sonoluminescence can produce raises the possibility that it might be a means to achieve thermonuclear fusion.cite news
first = Kenneth
last = Chang
authorlink =
quote = Dr. Putterman's approach is to use sound waves, called sonofusion or bubble fusion, to expand and collapse tiny bubbles, generating ultrahot temperatures. At temperatures hot enough, atoms can literally fuse and release even more energy than when they split in nuclear fission, now used in nuclear power plants and weapons. Furthermore, fusion is clean in that it does not produce long-lived nuclear waste.
title = Practical Fusion, or Just a Bubble?
url = http://www.nytimes.com/2007/02/27/science/27fusion.html?8dpc
work =
publisher = New York Times
date = February 27, 2007
accessdate = 2007-02-27]

Original experiments

US patent 4,333,796, [Ref patent|country= US|number= 4333796|title= Method of generating energy by acoustically induced cavitation fusion and reactor therefor|gdate = 1982-06-08|fdate= 1978-05-19|invent1= Flynn, Hugh G.] filed by Hugh Flynn in 1978, appears to be the earliest documented reference to a sonofusion-type reaction.

In the March 8, 2002 issue of the peer-reviewed journal "Science", Rusi P. Taleyarkhan and colleagues at the Oak Ridge National Laboratory (ORNL) reported that acoustic cavitation experiments conducted with deuterated acetone (carbon|3deuterium|6oxygen) showed measurements of tritium and neutron output that were consistent with the occurrence of fusion. The neutron emission was also reported to be coincident with the sonoluminescence pulse, a key indicator that its source was fusion caused by the sonoluminescence.cite journal
last = Taleyarkhan
first = R. P.
authorlink = Rusi Taleyarkhan
coauthors = C. D. West, J. S. Cho, R. T. Lahey, Jr. R. Nigmatulin, and R. C. Block
date = 2002-03-08
title = Evidence for Nuclear Emissions During Acoustic Cavitation
journal = Science
volume = 295
issue = 1868
id = ISSN 0036-8075
url = http://www.sciencemag.org/feature/data/hottopics/bubble/index.shtml
accessdate = 2007-05-13]

Shock wave simulations seem to indicate that the temperatures inside the collapsing bubbles may reach up to 10 megakelvins, i.e. as hot as the center of the Sun.cite web
last = Shapira
first = D.
coauthors = M. J. Saltmarsh
date = 2002-03-01
url = http://fire.pppl.gov/sono_saltmarsh_expts.pdf
title = "Comments on Reported Nuclear Emissions during Acoustic Cavitation"
format = PDF
publisher = Fusion Ignition Research Experiment (FIRE) Program
accessdate = 2007-05-13] cite journal
last = Taleyarkhan
first = R. P.
authorlink = Rusi Taleyarkhan
coauthors = R. C. Block, C. D. West and R. T. Lahey Jr.
date = 2002-03-02
url = http://www.rpi.edu/%7Elaheyr/SciencePaper.pdf
title = Comments on the Shapira and Saltmarsh Report
format = PDF
work = Dr. Richard T. Lahey, Jr. website
publisher = Rensselaer Polytechnic Institute
accessdate = 2007-05-13] cite journal
last = Becchetti
first = F.
date = 2002-03-08
title = Evidence for Nuclear Reactions in Imploding Bubbles
journal = Science
volume = 295
issue = 1850
doi = 10.1126
id = ISSN 0036-8075
doi_brokendate = 2008-06-25] cite journal
last = Kennedy
first = D.
date = 2002-03-08
title = To Publish or Not to Publish
journal = Science
volume = 295
issue = 1793
id = ISSN 0036-8075
doi = 10.1126/science.295.5561.1793
accessdate = 2007-05-13
pages = 1793
pmid = 11884720] Although the apparatus operates in a room temperature environment, this is "not" cold fusion (as commonly termed in the popular press) because the nuclear reactions would be occurring at the very high temperatures in the core of the imploding bubbles.

The researchers used a pulse of neutrons in order to nucleate ("seed") the tiny bubbles, whereas most previous experiments started with small air bubbles already in the liquid. Using this new method, the team was able to produce stable bubbles that could expand to nearly a millimeter in radius before collapsing. In this way, the researchers stated, they were able to create the conditions necessary to produce very high pressures and temperatures. The sensitivity of the fusion rate to temperature, which is in turn a function of how small the bubbles get when they collapse, in combination with the likely sensitivity of the latter to fine experimental details, may account for the fact that some research workers have reported to see an effect, while others have not.

Taleyarkhan "et al" also prepared identical experiments in non-deuterated (normal) acetone and failed to observe neutron emission or tritium production. Taleyarkhan claims his interest in bubble fusion began following a post-dinner chat with a friend, Dr. Mark Embrechts, in 1995.

Oak Ridge failed replication

These experiments were repeated at Oak Ridge National Laboratory by D. Shapira and M. J. Saltmarsh but using more sophisticated neutron detection equipment. They reported that the neutron release was consistent with random coincidence.cite journal
last = Shapira
first = D.
authorlink = Dan Shapira
coauthors = M. J. Saltmarsh
date = 19 August 2002
title = Nuclear Fusion in Collapsing Bubbles — Is it There? An Attempt to Repeat the Observation of Nuclear Emissions from Sonoluminescence
journal = Physical Review Letters
volume = v. 89
issue = letter 104302
id = ISSN 1079-7114 (online)
url = http://prola.aps.org/abstract/PRL/v89/i10/e104302
accessdate = 2007-05-13] A rebuttal by Taleyarkhan and the other authors of the original report said that the Shapira and Saltmarsh report failed to account for significant differences in experimental setup, including over an inch of shielding between the neutron detector and the sonoluminescing acetone. Taleyarkhan "et al" report that when these differences are properly considered, the Shapira and Saltmarsh results are consistent with fusion.Fact|date=May 2007

In addition, Galonsky has shown that by Taleyarkhan's own detector calibration the observed neutrons are too high in energy to be from a deuterium-deuterium (d-d) fusion reaction. In a rebuttal comment, Taleyarkhan says the energy is "reasonably close" to that which is expected.cite journal
last = Galonsky
first = A.
authorlink =
coauthors =
date = 6 September 2002
title = Tabletop Fusion Revisited
journal = Science
volume = 297
issue = 1645
doi = 10.1126
id = ISSN 0036-8075
doi_brokendate = 2008-06-25]

In February 2005, the BBC documentary series "Horizon" commissioned a collaboration between two leading sonoluminescence researchers, Seth Putterman and Ken Suslick, to reproduce Taleyarkhan's work. Using similar acoustic parameters, deuterated acetone, similar bubble nucleation, and a much more sophisticated neutron detection device, the researchers could find no evidence of a fusion reaction. This work was reviewed by a team of four scientists, including an expert in sonoluminescence and an expert in neutron detection, who also concluded that no evidence of fusion could be observed.cite news
url = http://news.bbc.co.uk/2/hi/science/nature/4270297.stm
title = Nuclear fusion 'put to the test'
work = BBC News
date = 17 February 2005
accessdate = 2007-05-13] cite web
url = http://www.bbc.co.uk/sn/tvradio/programmes/horizon/experiment_trans.shtml
title = "An Experiment to Save the World"
format = programme transcript
work = "Horizon"
publisher = BBC News
accessdate = 2007-05-13]

Subsequent reports of replication

In 2004, new reports of bubble fusion were published by the Taleyarkhan group, saying that the results of previous experiments have been replicated under more stringent experimental conditions. [cite news
first = Theresa
last = Bourgeois
title = Researchers Report Bubble Fusion Results Replicated: "Physical Review E" publishes paper on fusion experiment conducted with upgraded measurement system
url = http://news.rpi.edu/update.do?artcenterkey=65&setappvar=page(1)
publisher = RPI News & Information
date = 2 March 2004
accessdate = 2007-05-13] cite journal
last = Taleyarkhan
first = R. P.
authorlink = Rusi Taleyarkhan
coauthors = J. S. Cho, C. D. West, R. T. Lahey, R. I. Nigmatulin, and R. C. Block
date = 22 March 2004
title = Additional Evidence of Nuclear Emissions During Acoustic Cavitation
journal = Physical Review E
volume = 69
issue = letter 036109
doi = 10.1103
url = http://adsabs.harvard.edu/abs/2004PhRvE..69c6109T
accessdate = 2007-05-13
doi_brokendate = 2008-06-25] These results differed from the original results in that fusion was occurring for a much longer time frame than previously reported. The original report only showed neutron emission from the initial bubble collapse following bubble nucleation, whereas this report showed neutron emission many acoustic cycles later. The data, however, was less than stringent insofar as too large a window of measurement was used to determine a coincidence between neutron emission and sonoluminescent light emission. Furthermore, the energy of the detected neutrons was not consistent with neutrons produced from a fusion reaction.

In July 2005, two of Taleyarkhan's students at Purdue University published evidence confirming the previous result. They used the same acoustic chamber, the same deuterated acetone fluid and a similar bubble nucleation system. In this report, no neutron-sonoluminescence coincidence was attempted. Once again, the neutron energies measured were not consistent with those of neutrons produced by a d-d fusion reaction. [cite news
first = Emil
last = Venere
title = Purdue findings support earlier nuclear fusion experiments
url = http://news.uns.purdue.edu/html4ever/2005/050712.Xu.fusion.html
work = Purdue News
publisher = Purdue University
date = 12 July 2005
accessdate = 2007-05-13] cite journal
last = Xu
first = Y.
authorlink = Yiban Xu
coauthors = A. Butt
date = 3 May 2005
title = Confirmatory Experiments for Nuclear Emissions During Acoustic Cavitation
journal = Nuclear Engineering and Design
volume = 235
issue = 1317
pages = pp.1317–1324
doi = 10.1016
id = ISSN 0167-899X
doi_brokendate = 2008-06-25]

A paper published in the journal "Physical Review Letters" by researchers from Rensselaer Polytechnic Institute reports statistically significant evidence of fusion:cite journal
last = Peplow
first = Mark
date = 10 January 2006
title = Desktop fusion is back on the table
journal = Nature.com
doi = 10.1038/news060109-5
id = ISSN 1744-7933
url = http://www.nature.com/news/2006/060109/full/060109-5.html
accessdate = 2007-05-13
format = dead link|date=June 2008 – ^{[http://scholar.google.co.uk/scholar?hl=en&lr=&q=author%3APeplow+intitle%3ADesktop+fusion+is+back+on+the+table&as_publication=Nature.com&as_ylo=2006&as_yhi=2006&btnG=Search Scholar search]} ] cite journal
last = Taleyarkhan
first = R. P.
authorlink = Rusi Taleyarkhan
coauthors = C. D. West, R. T. Lahey, R. I. Nigmatulin, J. S. Cho, R. C. Block, and Y. Xu
month = January | year = 2006
title = Nuclear Emissions During Self-Nucleated Acoustic Cavitation
journal = Physical Review Letters
volume = 96
issue = letter 034301
doi = 10.1103/PhysRevLett.96.034301
url = http://adsabs.harvard.edu/abs/2006PhRvL..96c4301T
accessdate = 2007-05-13
pages = 034301 "...Statistically significant nuclear emissions were observed for deuterated benzene and acetone mixtures but not for heavy water. The measured neutron energy was <=2.45 MeV, which is indicative of deuterium-deuterium (D-D) fusion. Neutron emission rates were in the range ~5×10³ n/s to ~10⁴ n/s and followed the inverse law dependence with distance..."] cite news
url = http://www.sciencedaily.com/releases/2006/01/060130155542.htm
title = Using Sound Waves To Induce Nuclear Fusion With No External Neutron Source
work = Science Daily
publisher = Rensselaer Polytechnic Institute
date = 31 January 2006
accessdate = 2007-05-13 "...The experiment was specifically designed to address a fundamental research question, not to make a device that would be capable of producing energy, Block says...To verify the presence of fusion, the researchers used three independent neutron detectors and one gamma ray detector. All four detectors produced the same results: a statistically significant increase in the amount of nuclear emissions due to sonofusion when compared to background levels..."] The initial news report, however, shows that the reaction does not always work correctly and it is not known what parameters change to cause the reaction to function properly or not function at all.Fact|date=March 2008

In November 2006, in the midst of charges leveled at Taleyarkhan as regards his research standards, Dr. Edward R. Forringer and undergraduates David Robbins and Jonathan Martin of LeTourneau University presented two papers at the American Nuclear Society Winter Meeting that reported replication of neutron emission during a visit to the meta-stable fluids research lab at Purdue University. Their experimental setup was similar to the preceding experiments in that it used a mixture of deuterated acetone, deuterated benzene, tetrachloroethylene and uranyl nitrate. Notably, however, it operated without an external neutron source and used two types of neutron detectors. They claimed a liquid scintillation detector measured neutron levels at 8 standard deviations above the background level, while plastic detectors measured levels at 3.8 standard deviations above the background. These measurements were within one standard deviation for the same experiment with a non-deuterated control liquid, indicating that the neutron production had only occurred during cavitation of the deuterated liquid."Bubble Fusion Confirmed by LETU Research" LeTourneau University News (www.letu.edu/opencms/opencms/events/Bubble_Fusion_Confirmed_by_LETU_Research.html) link inactive as of 2008-05-10] cite web
url = http://www.ans.org/meetings/docs/2006/wm2006-official.pdf
title = "Technical Sessions by Day (Wednesday)"
work = ANS 2006 Winter Meeting & Nuclear Technology Expo Official Program
format = PDF
page = 24
date = November 12-16, 2006
accessdate = 2006-12-06 (confirmation of presentation)] cite journal
last = Forringer
first = Edward R.
authorlink = Edward Forringer
coauthors = David Robbins, Jonathan Martin
date = 12 November 2006
title = Confirmation of Neutron Production During Self-Nucleated Acoustic Cavitation
journal = Transactions of the American Nuclear Society
volume = v.95
pages = p.736
id = ISSN 0003-018X]

Doubts prompt investigation

Reports as spectacular as the above arouse a lot of doubt. In March 2006, "Nature" published a "special report" "silencing the hype" that called into question the validity of the results of the Purdue experiments. [cite journal
date = 8 March 2006
title = Bubble fusion: silencing the hype
journal = Nature.com
doi = 10.1038/news060306-1
id = ISSN 1744-7933
url = http://www.nature.com/news/2006/060306/full/060306-1.html
accessdate = 2007-05-13
format = dead link|date=June 2008 &ndash; ^{[http://scholar.google.co.uk/scholar?hl=en&lr=&q=intitle%3ABubble+fusion%3A+silencing+the+hype&as_publication=Nature.com&as_ylo=&as_yhi=&btnG=Search Scholar search]}
doi_brokendate = 2008-06-25] The report quotes Brian Naranjo of the University of California, Los Angeles to the effect that spectrum measured in these sonofusion experiments is consistent with radioactive decay of the lab equipment and hence does not reliably demonstrate the presence of nuclear reactions.cite journal
last = Naranjo
first = Brian
date = 3 October 2006
title = Comment on 'Nuclear Emissions During Self-Nucleated Acoustic Cavitation'
journal = Physical Review Letters
volume = 97
issue = letter 149403
doi = 10.1103/PhysRevLett.97.149403
pages = 149403]

The response of Taleyarkhan "et al", published in "Physical Review Letters", attempts to refute Naranjo's hypothesis as to the cause of the neutrons detected.cite journal
last = Taleyarkhan
first = R. P.
coauthors = R. C. Block, R. T. Lahey, Jr., R. I. Nigmatulin, and Y. Xu
date = 3 October 2006
title = Taleyarkhan et al. Reply:
journal = Physical Review Letters
volume = 97
issue = letter 149404
doi = 10.1103/PhysRevLett.97.149404
pages = 149404]

Doubts at Purdue University's Nuclear Engineering faculty as to whether the positive results reported from sonofusion experiments conducted there were truthful prompted the university to initiate a review of the research, conducted by Purdue's Office of the Vice President for Research. In a March 9, 2006 article entitled "Evidence for bubble fusion called into question", "Nature" interviewed several of Taleyarkhan's colleagues who suspected something was amiss.cite journal
last = Reich
first = Eugenie Samuel
date = 9 March 2006
title = Evidence for bubble fusion called into question
journal = Nature
volume = 440
issue = 132
doi = 10.1038/440132b
pages = 132]

In his piece "On Science, Journalism, and "Nature", "New Energy Times" writer Steven Krivit poses some questions about "Nature's" coverage of the affair.cite web
last = Krivit
first = Steven B.
date = 10 March 2006
url = http://newenergytimes.com/news/2006/NET15.htm#bubbletrouble
title = "On Science, Journalism, and Nature"
work = New Energy Times, Issue 15
accessdate = 2007-05-13]

On February 7, 2007, the Purdue University administration determined that "the evidence does not support the allegations of research misconduct and that no further investigation of the allegations is warranted". Their report also stated that "vigorous, open debate of the scientific merits of this new technology is the most appropriate focus going forward."cite news
url = http://news.uns.purdue.edu/x/2007a/070207BennettTaleyarkhan.html
title = Purdue integrity panel completes research inquiry
work = Purdue News
publisher = Purdue University
date = 7 February 2007
accessdate = 2007-05-13] cite news
first = Kenneth
last = Chang
url = http://www.nytimes.com/2007/02/13/science/13purd.html
title = Researcher Cleared of Misconduct, but Case Is Still Murky
work = New York Times
edition = Late Edition (Final)
page = F-4
date = February 13, 2007
accessdate = 2007-05-13] In order to verify that the investigation was properly conducted, House Representative Brad Miller requested full copies of its documents and reports by March 30, 2007.cite web
title = Miller Seeks Data on Purdue Investigation Into Scientific Misconduct
url = http://science.house.gov/press/PRArticle.aspx?NewsID=1734
publisher = House Committee on Science and Technology
date = 22 March 2007
accessdate = 2007-05-13]

On March 7, 2008, Taleyarkhan filed a civil complaint against his boss Tsoukalas and colleague Jevremovic with the state of Indiana regarding events that occurred in the Purdue School of Nuclear Engineering. [cite web
title = Purdue University Punishes Bubblegate Researcher
url = http://newenergytimes.com/BubbleTrouble/2008-August-Sanction.htm
publisher = New Energy Times
date = August 31, 2008
accessdate = 2008-08-31]

In June 2008, a multi-institutional team including Taleyarkhan publishes a paper in Nuclear Engineering and Design to "clear up misconceptions generated by a webposting of UCLA which served as the basis for the Nature article of March 2006", according to a press release. [cite journal
last = Taleyarkhan
first = R.P.
date = June 2008
title = Modeling, Analysis and Prediction of Neutron Emission Spectra From Acoustic Cavitation Bubble Fusion Experiments
journal = Nuclear Engineering and Design
volume = 2008
issue = 238
doi = 10.1016/j.nucengdes.2008.06.007
pages = 2779-2791, cited by cite web
title = Bubble Fusion Studies Vetted and Cleared by NED
url = http://www.newenergytimes.com/BubbleTrouble/2008RT-PressRelease0826.pdf
publisher = Lewis and Wilkins
date = August 26, 2008
accessdate = 2008-09-04]

On July 18, 2008, Purdue University announced that a committee with members from five institutions has investigated 12 allegations of research misconduct by Rusi Taleyarkhan. It concluded that two allegations were founded—that Taleyarkhan had claimed independent confirmation of his work when in reality the apparent confirmations were done by Taleyarkhan's former students and was not as "independent" as Taleyarkhan implied, and that Taleyarkhan had included an additional colleague's name on one of his papers who had not actually been involved in the research ("the sole apparent motivation for the addition of Mr. Butt was a desire to overcome a reviewer's criticism," the report concluded). [cite web
title = Purdue committee completes research misconduct investigation
url = http://news.uns.purdue.edu/x/2008b/080718BennettTaleyarkhan.html
publisher = Purdue University
date = 18 July 2008
accessdate = 2008-07-18] [cite web
title = Report of the Investigation Committee In the Matter of Dr. Rusi P. Taleyarkhan
url = http://news.uns.purdue.edu/x/2008b/080718PurdueReport.pdf
publisher = Purdue University
date = 18 April 2008
accessdate = 2008-07-19
format=PDF] However, in a previous press release in July 2005, Purdue University had said that Butt's replication was independent from Taleyarkhan [cite web
title = Purdue findings supports earlier nuclear fusion experiments
url = http://www.purdue.edu/UNS/html4ever/2005/050712.Xu.fusion.html
publisher = Purdue University
date = 12 July 2005
accessdate = 2008-09-04, cited by cite web
title = Bubblegate Conflict at Purdue - Timeline Overview
url = http://www.newenergytimes.com/BubbleTrouble/BubblegateTimelineOverview.htm
publisher = New Energy Times
accessdate = 2008-09-04]

Taleyarkhan appealed the conclusions in the report, but this was rejected. He said the two allegations of misconduct were trivial administrative issues and had nothing to do with the discovery of bubble nuclear fusion or the underlying science, and that "all allegations of fraud and fabrication have been dismissed as invalid and without merit — thereby supporting the underlying science and experimental data as being on solid ground". cite web
first = K. S.
last = Jayaraman
url = http://www.nature.com/nindia/2008/080901/full/nindia.2008.271.html;jsessionid=4j2svxic4rcm
title = Bubble fusion discoverer says his science is vindicated
publisher = Nature India
doi = 10.1038/nindia.2008.271
accessdate = 2008-09-01 ]

On August 27, 2008 he was stripped of his named Arden Bement Jr. Professorship, and forbidden to be a thesis advisor for graduate students for at least the next 3 years.cite news
first = Associated
last = Press
url = http://www.sfgate.com/cgi-bin/article.cgi?f=/n/a/2008/08/27/national/a140220D17.DTL&feed=rss.business
title = Purdue reprimands fusion scientist for misconduct
publisher = San Francisco Chronicle
date = August 27, 2008
accessdate = 2008-08-28 ] cite web
first = K. S.
last = Jayaraman
url = http://www.nature.com/nindia/2008/080901/full/nindia.2008.271.html;jsessionid=4j2svxic4rcm
title = Bubble fusion discoverer says his science is vindicated
publisher = Nature India
doi = 10.1038/nindia.2008.271
accessdate = 2008-09-01 ]

See also

* List of energy topics
* "Chain Reaction", a movie portraying the discovery and attempted cover-up of a practical acoustic fusion reactor.

References

External links

* [http://newenergytimes.com/BubbleTrouble/BFControversy.htm The bubble fusion controversy] on [http://newenergytimes.com/ New Energy Times]

News

* [http://newenergytimes.com/BubbleTrouble/NETBubbleFusionSpecialReport.pdf The New Energy Times Special Report on Bubble Fusion/Sonofusion]
* [http://www.plotkin.com/blog-archives/2007/02/the_strange_cas.html The Strange Case of Dr. Rusi Taleyarkhan by Hal Plotkin] What I Really Want to Say.com 2 February 2007
* [http://www.spectrum.ieee.org/may05/1119 "Bubble Power"] , Richard T. Lahey Jr., Rusi P. Taleyarkhan & Robert I. Nigmatulin, IEEE Spectrum Magazine, May 2005 — Readable, quantitative, illustrated article
** [http://www.spectrum.ieee.org/may06/3428 "Bubble Fusion Research Under Scrutiny"] , IEEE Spectrum, May 2006, follow-up on May 2005 article
* R. T. Lahey Jr, R. P. Taleyarkhan, and R. I. Nigmatulin, [http://www.rpi.edu/~laheyr/Sonofusion%20Paper-pdf_Lahey_NURETH-11.pdf Sonofusion — Fact or Fiction?] (PDF format)
* [http://web.archive.org/web/20050204055257/www.rpi.edu/web/News/press_releases/2002/bubblefusion.html "Possible Sound-Induced Nuclear Fusion Posited"] Rensselaer Polytechnic Institute Press Release, March 5, 2002
* [http://news.bbc.co.uk/hi/english/sci/tech/newsid_1855000/1855672.stm "Fusion controversy rekindled"] BBC News, March 5, 2002
** [http://news.bbc.co.uk/2/hi/sci/tech/2151215.stm "Fusion experiment disappoints"] BBC News, July 2, 2002
* [http://news.uns.purdue.edu/html4ever/2004/0400302.Taleyarkhan.fusion.html "Evidence bubbles over to support tabletop nuclear fusion device"] March 2, 2004
* [http://physicsweb.org/article/news/6/2/3 "Sound waves size up sonoluminescence"] . PhysicsWeb. February 5, 2002
* [http://news.rpi.edu/update.do?artcenterkey=65&setappvar=page(1) "Researchers Report Bubble Fusion Results Replicated"] Rensselaer Polytechnic Institute Press Release, March 2, 2004
* [http://www.newscientist.com/article.ns?id=mg18524831.100 Harnessing bubbles to trigger nuclear fusion] — 22 January 2005, Justin Mullins, New Scientist Magazine Issue 2483 (subscription required)
* [http://news.uns.purdue.edu/UNS/html4ever/2005/050712.Xu.fusion.html Purdue findings support earlier nuclear fusion experiments] — New positive bubble/sonofusion findings were detailed in a peer-reviewed paper appearing in the May issue of the journal Nuclear Engineering and Design. (July 12 2005)
* [http://www.heise.de/tp/r4/artikel/20/20542/1.html Bubble Fusion takes next hurdle] — The potential for cavitation to induce nuclear fusion lets physicists think in new directions of energy production. (July 18 2005)
* [http://www.nature.com/news/2006/060109/full/060109-5.html "Desktop fusion is back on the table; Physicist claims to have definitive data, but can they be replicated?"] , [e-mail], January 10 2006 (subscription required)
* [http://physorg.com/news10336.html "Sonofusion Experiment Produces Results Without External Neutron Source"] "PhysOrg.com" January 27, 2006
* [http://www.sciencedaily.com/releases/2006/01/060130155542.htm "Using Sound Waves To Induce Nuclear Fusion With No External Neutron Source"] (sciencedaily.com, January 31 2006)
* [http://www.nature.com/news/2006/060306/full/060306-1.html "Bubble fusion: silencing the hype"] , "Nature" online, March 8, 2006 — Nature reveals serious doubts over reports of fusion in collapsing bubbles (subscription required)
* [http://bobpark.physics.umd.edu/WN06/wn031006.html What's New, March 10, 2006 - failed replications]
* [http://www.nature.com/news/2006/060508/full/060508-8.html "Bubble-fusion group suffer setback; Team admits a mix-up with one of their neutron detectors"] , May 10, 2006, [e-mail] (subscription required)
* [http://www.photonics.com/content/news/2006/June/21/83135.aspx "Purdue Bubble Wraps Sonofusion Inquiry Results"] , June 21, 2006 Photonics.com
* [http://www.imdb.com/title/tt0115857/ "Chain Reaction"] Movie, August 1996
* [http://www.sonofusionjets.com/ "Introduction to Sonofusion"] Roger Stringham, October 2006
* [http://www.nytimes.com/2007/02/27/science/27fusion.html?_r=1&oref=slogin "Practical Fusion, or Just a Bubble?"] , Kenneth Chang, The New York Times, February 27, 2007