Not being very competent or informed, I searched Google to find expert critiques of Widom-Larsen theory:
1 of 126 pages of discussion re Rossi reactor -- started by djolds1 Joined: 13 Jul 2007 Posts: 863 Posted: Thu Jan 13, 2011 7:16 pm Post subject: 10KW LENR Demonstrator? includes: http://www.talk-polywell.org/bb/viewtopic.php?t=2829&postdays=0&postorder=asc&start=1440 for a discussion re Widom-Larsen theory started by tomclarke Joined: 05 Oct 2008 Posts: 463 Location: London Posted: Tue May 17, 2011 4:46 pm http://www.talk-polywell.org/bb/viewtopic.php?p=61762 which supplies this: http://www.newenergytimes.com/v2/sr/WL/critique/2008Hagelstein-ElectronMassShift.pdf Electron mass shift in nonthermal systems P L Hagelstein 1, I U Chaudhary 2 1 Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, MA 02139,USA E-mail: [email protected] 2 Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, MA 02139,USA E-mail: [email protected] 23 Jan., 2008 23 pages, 24 references Abstract. The electron mass is known to be sensitive to local fluctuations in the electromagnetic field, and undergoes a small shift in a thermal field. It was claimed recently that a very large electron mass shift should be expected near the surface of a metal hydride [Eur. Phys. J. C, 46 107 (2006)]. We examine the shift using a formulation based on the Coulomb gauge, which leads to a much smaller shift. The maximization of the electron mass shift under nonequilibrium conditions seems nonetheless to be an interesting problem. We consider a scheme in which a current in a hollow wire produces a large vector potential in the wire center. Fluctuations in an LC circuit with nearly matched loss and gain can produce large current fluctuations; and these can increase the electron mass shift by orders of magnitude over its room temperature value. a supportive critique: http://www.newenergytimes.com/v2/sr/WL/critique/WLTheoryNavyCritique.shtml Critique of Widom-Larsen Theory by Dave Rees, Particle Physicist with U.S. Navy SPAWAR From: xxxxxxx.navy.mil] Sent: Monday, September 11, 2006 15:19 To: Boss, Pam SPAWAR Cc: Rees, Dave SPAWAR; Boss, Roger SPAWAR; Gordon, Frank SES SPAWAR 230 Subject: Re: Metal Hydride cathode catalysis of e + p -> nu + n Hi xxxx. I've finished looking through the paper. Important qualifier: it has been awhile since I have thought about these types of calculations, so take this with a grain of salt. My overview: This paper uses standard quantum field theory (nonrelativistic limit) and various uniformity and simplest-case-type assumptions to calculate an estimate of the rate for p + e- -> nu (neutrino) + n (neutron). The techniques used are all conventional and frequently used. There are a number of simplifying assumptions made that then allow a simple closed-form estimate. The final estimate is that the rate is of order 10^13 to 10^14 per unit area per unit time when a cutoff parameter (expressed in terms of effective electron mass) is exceeded. It is claimed that this is compatible with observed rates. The basic idea is straightforward and closely related to basic semiconductor physics where "holes" (vacancies in a lattice) can be treated as massive charged particles - the net effect of the medium is to add an "effective mass" (to a pretty good first-order approximation). Normally one would not expect a significant transition rate because the reaction is energy-forbidden (mass(p) + mass(e-) <mass(n) by a significant amount). However, due to the strong currents and surface effects at a metal hydride cathode, there will be significant radiation field interaction with electrons in this zone. This radiation field interaction, to lowest order, can manifest as an increased "effective mass" for electrons. If the effect is great enough, the reaction can proceed. This idea seems reasonable. The authors use a four-fermi vertex interaction to estimate the rate. I followed through the work and all calculations seemed to be consistent with standard practice, and to be correct so far as I can tell. I can't say that I followed every factor of pi through. The baryon operators (p, n) are handled in terms of isospin, should be a good approach for the nonrelativistic regime here. A standard phase space integration is used to compute the transition rate; I don't see any problems with it. My assessment: The basic idea seems reasonable; I don't see any reason it shouldn't be correct. In fact, it is the most obvious way to proceed. All the calculations seem to be correct as far as I can tell. If there is any problem (it seems to me), it is in the assumptions made for simplification, or in something subtle that would prevent the sort of straightforward approach the authors use. Thus I list the key assumptions I saw and my guess as to their impact here. 1. "if there are n(2) ~ 10^15/cm^2 effective (e*- p+) pairs per unit surface area [in the surface zone] ..." - I haven't a clue as to if this is reasonable or not (chemists might know better!). It would at least seem to be compatible with Avogadro's number, for what that is worth. BTW, this number is key to the estimated rate. 2. Non-relativistic - Likely fine. Slight possibility of issues with mass(W). 3. Surface isotopic spin wave approach - Seems good to me. 4. Patch size for the isotopic spin wave - I don't know how to estimate this. A good distribution for this would likely permit a neutron energy-spectrum estimate, which would be a good verification tool. 5. The effective mass wave function transformation - I can't see why this wouldn't be correct 6. Proton spins are uncorrelated and free neutron density is dilute - Neutron density dilute almost certainly correct. Proton spins - I don't know. 7. "The calculation of K depends on the detailed physical properties of the cathode surface as well as the flux per unit area per unit time of electrons ..." "In the most simple model, let us consider a smooth surface ..." - Gory details could be important, as authors note. 8. "... let us consider ... electron currents ... via the mass renormalization parameter beta as defined in eq. 46." - Basically after lots of calculation and some simplifying assumptions, the authors just *assume* that the mass renormalization approach is the way to go. This happens between equations 61 and 62 and is key to the result. I suspect the authors are right ( can't see why this wouldn't be correct, as per 5 above), but more work could go into this step. 9. Infrared/Ultraviolet cutoffs - In such a radiative coupling rich environment, cutoffs could impact this approach. In the strictly nonrelativistic four-point vertex, I think is probably OK. I think. Bottom line: Techniques and calculations are straightforward, and (as far as I can tell) correct. There could be some assumptions that need to be dealt with in more detail (could spell trouble). My "feel" is that they are OK. The paper looks good to me. It's a clever idea, I think (clever ideas are always obvious in hindsight). Best, Dave a negative take: http://www.lead411.com/Akito_Takahashi_6676638.html Site: http://www.newenergytimes.com/v2/sr/WL/critique/WLTheoryTakahashiCritique.shtml Critique of Widom-Larsen Theory by Dr. Akito Takahashi [Ed. note: Dr. Akito Takahashi of Osaka University provided the following critique of the Widom-Larsen theory to New Energy Times. His critique was presented in the paper "Progress in Condensed Matter Nuclear Science" and published in the proceedings of the 12th International Conference on Condensed Matter Nuclear Science (p. 21-23, World Scientific, 2006). It is excerpted here. Widom and Larsen have declined the request for a rebuttal.] 1) Production cross section of heavy electrone* is not given, so that we can not argue on density of very-low-momentum-neutron (VLMN) available in matter, taking into account of 10 min beta-decay of neutrons and assumed neutron-conversion cross section (see 3) If neutron density were greater than 1E+16 per cm^2 on surface, neutron reaction rate with H and host metal-nuclei were realistic level as experiments claim. According to neutron decay and inelastic phonon-scattering with lattice vibration, which is up-scattering to higher neutron energy, we need to estimate mean existing time of VLMN on surface. (I guess VLMNs get phonon energy with several barns of cross section and very rapidly in less than one micro-second- leak out.) 2) Proton (deuteron) on metal surface lattice vibrates with (1/2pi)h-omega, as Einstein oscillator, and has recoil energy of about 30 meV. VLMN converted from proton should conserve this 30 meV as kinetic energy which is a little more than averaged (thermal equilibrium) energy of 25 meV in media at room temperature. (Einstein oscillator can have higher zero-point energy than Debye oscillators of metal atoms.) 3) Cross section for p + e* to n + neutrino is not given. I think this cross section (over threshold energy as Widom-Larsen show) should be very much small, on the order of 1E-26 of usual strong interactions. And neutrino here is different from electron-neutrino and muon-neutrino. This cross section (or transition matrix) estimation is key problem for making the Widom-Larsen theory realistic! 4) Li-6 + n to He-4 + t + 4.8 MeV channel has about 1000 barns at En=25 meV, compared with very small cross section 4E-2 barns for n-capture, Li-6 + n to Li-7 + gamma. And Li-7 + n to Li-8 to Be-8 + beta to He-4 + He-4 + e process has 4E-2 barns at En= 25 meV, only. So, it is well known that Li-6 + n to He-4 + t + 4.8 MeV is predominant channel! Since reaction rate per neutron flux is (cross section)x(velocity) and cross section at lower energy than 30 meV has 1/v law, all reaction rates keep constant according to the change of momentum or kinetic energy. So that, even at very much low energy, reaction rate does not increase so. I think Widom-Larsen misunderstand these points. 5) If p + e* state exists, it should have transition to mini-atom orbit which should emit photons greater than 13.6 eV of H-atom ground state. (This has some sort of relation to Randy Mills' sub-orbital quantum state, hydrino!) We need to estimate life time of e* becoming heavy by Widom-Larsen's oscillating electro-magnetic plasmon interaction on surface. 6) If hard gamma-rays were totally absorbed by e*, we can easily test using a standard gamma-ray source to measure gamma-peak attenuation through the sample metal-hydride surface. We have no data for Compton scattering with e*, which they assume very much large to neglect gamma-electron processes with metal-atoms having usually much larger photo-electric, Compton and pair-creation cross sections compared with those for hydrogen atom. 7) We know, dde*(mass=208m-electron), namely muonic dd-molecule does not emit low energy neutrons (but 2.45 MeV neutron by d-d fusion), although Widom-Larsen theory suggests dde* to d + n+ n break-up.
