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VARIABILITY OF NUCLEAR DECAY RATES

0 Post author: morganism 13 November 2016 11:57PM

 

I came across a utube vid about this is 08 or so, a talk at a convention, and it intrigued me, but didn't know anyone was working on studying it. The guy set up a counter in the basement, and was tracking Cesium decay, to compare to a Web clock, IIRC. Can't find it now, topic is swamped, and duckgo swamped with creationist blogs, i guess they like the idea of radiodating flaws.

After many dueling papers, it appears the big neutrino sensor in Japan has seen the same, seasonal variability in their data too, so appearing more legit.

http://news.stanford.edu/2016/11/09/stanford-solar-physicist-unlocks-easier-way-observe-peculiar-particles-reveal-inner-workings-sun/

http://link.springer.com/article/10.1007%2Fs11207-016-1008-9

 

MIT collection

VARIABILITY OF NUCLEAR DECAY RATES

 

Original paper:

http://www.sciencedirect.com/science/article/pii/S092765050900084X

https://arxiv.org/abs/0808.3283

"Unexplained periodic fluctuations in the decay rates of 32Si and 226Ra have been reported by groups at Brookhaven National Laboratory (32Si), and at the Physikalisch–Technische–Bundesanstalt in Germany (226Ra). We show from an analysis of the raw data in these experiments that the observed fluctuations are strongly correlated in time, not only with each other, but also with the time of year."

and a review article, from the old Analog magazine!

Radioactive Decay and the Earth-Sun Distance

https://www.npl.washington.edu/AV/altvw147.html

 

This paper consolidates the data on six of the studies, while taking some simple, EM measurements of the Plank length variation that seems to coincide fairly closely with the decay rate data. Both are trailing the actual distance measurements by up to a month, which is pretty strange in its own right.

pdf

http%3A%2F%2Ffile.scirp.org%2Fpdf%2FOPJ_2016063013301299.pdf

Along with the Plank variation, lots of other explanations have been floated, my favorite being the link to a possible Dark Matter reservoir, that may reside in the Sun. This may also be one of the possible factors in the appearance of possible discrepancies in physics parameters at large Z regions of the universe, including some Type Ia supernova, that are used as distance markers.

The Sun Goes Through Seasonal Changes Too

https://www.youtube.com/watch?v=X7BWrWBABJw

Annual Modulation of Dark Matter: A Review

https://arxiv.org/abs/1209.3339

Constraining spacetime variations of nuclear decay rates from light curves of type Ia supernovae by Ivan Karpikov et al. [2015/01]

Radionuclides chart, with decay variations.

http://www.nndc.bnl.gov/chart/

Sunspot numbers, java, I can't see if there is any alignment there, tho there was a paper on solar flares.

http://www.spaceweather.com/java/archive.html

pdf:

Perturbation of Nuclear Decay Rates During the Solar Flare of 13 December 2006ďż˝, Jere H. Jenkins and Ephriam Fischbach, arXiv preprint 0808.3156 [astro-ph], August 22, 2008.

and archives of solar data, someone might be able to find other correlations.

http://www.ngdc.noaa.gov/stp/spaceweather.html

 

The same folks that did some original studies, also did a follow up, showing NO effect, but i guess that has been superseded. Someone also did a study on the Cassini RTG, but found no effect, tho with no internal access, and a U238 nucleotide, may not be as robust.

http://phys.org/news/2014-10-textbook-knowledge-reconfirmed-radioactive-substances.html#jCp

 

So, if decay rates are fluctuating, does that show that the simulation theory is not likely (not fine-grained enough), or that we don't even know what we don't know? Seems like a variable like this wouldn't be modeled in a sim...?

 

 

 

 

 

 

 

 

 

Comments (4)

Comment author: shev 15 November 2016 11:58:00PM *  1 point [-]

This is interesting, but I don't understand your questions at end. What simulation theory are you talking about?

By the way, one of your links is broken and should be http://file.scirp.org/pdf/OPJ_2016063013301299.pdf .

Keep in mind that there is a significant seasonal variation in emissions from the sun, such as neutrinos which can easily penetrate into any experimental apparatus on earth. This is simple to rationalize: the sun emits massive numbers of neutrinos, which pass through areas at a shallower angle in the winter and thus have lower flux.

By far the first thing to rule out would be neutrinos affecting nuclear decay, before we start wondering about dark matter or anything like that. Everyone in the business has thought of this, of course: http://physicsworld.com/cws/article/news/2008/oct/02/the-mystery-of-the-varying-nuclear-decay .

Occam's razor would suggest you should be extremely skeptical of any suggestion that it's more likely that something besides neutrinos is responsible for this effect, even if the mechanism hasn't been figured out yet.

Comment author: morganism 08 January 2017 08:35:15PM 0 points [-]

This is an update to a dark matter detector that was finding some variability, and they havn't found the same. Not sure what type of detector was used in previous study

Search for Electronic Recoil Event Rate Modulation with 4 Years of XENON100 Data

https://arxiv.org/abs/1701.00769

Comment author: morganism 03 December 2016 09:44:24PM 0 points [-]

another article author interview

http://www.stanforddaily.com/2016/12/01/physicists-propose-new-system-for-detecting-neutrinos/

“If the effects that we’re seeing are really due to neutrinos then they are interacting with matter in an entirely new way,” Fischbach said. “You cannot explain this phenomenon if they are attributed to neutrinos in any conventional way, so some new piece of physics must be out there.”

If these decay rate variations cannot be attributed to neutrinos, the discovery of non-stochastic, non-constant decay rates still raises the question of what forces are causing the variations.

“It’s also possible that we’re seeing the effects of other kinds of matter, so called dark matter, and a lot of things out there that can produce effects that look like neutrinos,” Fischbach said. “Since our lives depend on assuming radioactive decay rates are constant [i.e. carbon dating, medical applications], if they’re not, there will be a lot of changes in the way we [think of] things.”

Comment author: DanArmak 14 November 2016 06:24:51PM *  0 points [-]

Seems like a variable like this wouldn't be modeled in a sim...?

I don't know anything about physics, but if that were true, why not equally predict that lots of things that definitely exist wouldn't be included in a sim? Both the laws of physics and the actual universe seem to be a lot more complex than what's needed to simulate a classical Earth in a solar system.

Of course, that assumes you know what is and isn't of interest to the simulators, e.g. because it's an ancestor simulation.