In 1972, Scientists Discovered a Two Billion-Year-Old Nuclear Reactor In Gabon | Hacker News Reader

In 1972, Scientists Discovered a Two Billion-Year-Old Nuclear Reactor In Gabon

iafrikan.com

163 pointstefo-mohapi38 comments

> Davis and co point out that the Oklo data can also constrain changes in other constants, such as the ratio of light quark masses to the proton mass. To date, this work is consistent with these constants being constant.

In the history of science, how many 'constants' have, so far, been shown not to be constant?

Not to my knowledge. It's not an idle question, though -- the suggestion that physical constants might have changed over time arose not arbitrarily, but as a result of work in theoretical physics (Dirac's large number hypothesis, as well as a number of models that predict non-constant constants).

Remember that just over a hundred years ago one might equally well have asked "in the history of science, how many things have been shown to have constant velocity in all reference frames?"

Depends on what you mean. There have been a lot of implicit constants that change, F = (k) * MA. So, saying constant changes really just means there is another term in the equation that people are ignoring and lumping in with some constant.

It sounds specious but some ‘parameters’ are sometimes taken to be constant and then turn out to vary in relation to other parameters (such as time). This distinction between what we ”take to be” constant and that which is stringently and formally defined as being a specific value is a vast cognitive chasm.

The fine structure "constant," mentioned in the article actually varies with energy scale (although that's not the concern in the article).

Could you explain what you mean here? I can't tell what you're referring to.

Well, from my non-physicist's understanding of the matter: the fine structure constant is associated with the strength of electromagnetic interactions. The value we call the "fine structure constant" that's about ~1/137 in the equations is the lower bound of that strength, the strength of the interaction when you're dealing with energies about the same size as the electron mass. However, when you're dealing with higher energies, the interaction is stronger.

The interesting question as far as I can tell isn't related to how electromagnetism's strength varies over different energy scales, but whether the strength of electromagnetism at a given energy scale varies over time or space.

This is more or less correct, ~1/137 corresponds to zero momentum transfer (or equivalently infinite distances). This is because of screening by particle-antiparticle pairs at larger distances. See e.g. the first few slides of http://www.fysik.su.se/~clement/teaching/emparfys/2010-2011/... (one of the first things I found in a quick search).

To my knowledge none, but there do exist problematic constants that we can't measure consistently. Famously, measurements of the gravitational constant G vary in a pattern that repeats every 5.9 years. There are a few theories about this systematic error but no solid supporting evidence in experiment form.

tl;dr No constants have been proven not-constant but there are some that might be pending further research

This is quite interesting, is there a paper or some source of information related to this?

http://www.researchgate.net/publication/274780565_Measuremen...

Here's a relevant link: http://phys.org/news/2015-04-gravitational-constant-vary.htm...

There was some concern that the rate of radioactive decay was altered based on the Earth-Sun distance, but that's been disproven: http://phys.org/news/2014-10-textbook-knowledge-reconfirmed-...

I wonder if this variation in G is similar.

Steven Baxter’s ”Manifold: Space“ features one of these in a sort of Planet of the Apes scenario. Great book. https://en.m.wikipedia.org/wiki/Manifold:_Space

As a side-note, it's always weird to me to see place like Gabon or Congo called "West Africa".

It's clearly on the West Coast but within Africa, the West starts after Cameroon.

Just curious, but what would the accurate geographic descriptor of a west coastal, but not on the western subcontinent be called? The Congo is generally called central Africa in my experience, but that wouldn't really be accurate for Gabon/Angola, would it?

It would be accurate for Gabon and debatable (but not inaccurate) for Angola.

Basically, we think about these blocks:

- West Africa

- North Africa

- East Africa

- Southern Africa

- Central Africa

Now some countries are "on the border" and the description depends more on cultural or economical ties than pure geography.

Angola could be southern or Central. Zambia could be eastern or central (or even southern) Uganda could be eastern or central.

It's complicated: https://en.wikipedia.org/wiki/African_Union#Role_of_Regional...

But Gabon is definitely Central Africa.

It would be like someone calling Orlando, western USA. It's on a west coast, and if you were to head west you would likely hit Mexico (maybe Texas...) but it's obviously not western USA.

I think you meant Tampa?

You are right. I'm not from Florida (obviously).

One interesting thing about this is that it represents a race, between the concentration of Uranium in high-grade ores through geological processes (which requires the Earth to have formed, and so on and so on) on the one hand and the reduction in abundance of U-235 in natural Uranium over time due to radioactive decay.

> The one exception was a shallow reactor zone at a place called Bangombé, some 30 kilometres from Oklo, although this has largely been washed out by ground water.

That doesn't sound that safe to me after all.

I don't necessarily want to start a giant derail here, but this thing has some social significance in that it resuscitated some pseudo-scientific claims about advanced ancient human civilizations ala Atlantis, that suffered cataclysm and disappeared from history.

Not human civilizations. 2 billion years is a lot of time... but it might be weak evidence that we are not the first technological species in this planet. If you consider that we are probably not the only intelligent species on the planet just now, it sounds at least plausible to me.

Sure, pseudoscience has unlimited explanations :-) I've also heard it explained as the engine from a crashed alien spaceship.

This is simply astounding.

Yes, it truly is. Like, a real wonder of the nature of the universe.

What's truly amazing is the emergent properties of nature that lead to natural structures such as this.

It makes me wonder if we can create cellular automata made from materials at a nano-scale to mimic this process. Then you're one step away from a Von-Neumann Universal Constructor.

I always wondered if this ever happened naturally... Guess I now haev a confirmation. Nice... I suppose.

FWIW, the title on this post scans like the number 28 as opposed to the number 2 billion (to my eye, anyway).

Yes, unfortunately the title was changed automatically by an HN title parser upon submission. It changes references of million to M and billion to B.

But it didn't change your most recent submission?

Isn't this just someone trying to fit in the 80 char limit? Current title is 80 chars, so there's not enough room for the illion.

It did change it, that's how I noticed in the first place. In my case I went back and re-edited the title and that seemed to make it stick to "million" instead of "M."

My brain accepted 2B but then assumed it was a model of reactor. The idea of it being billions of years old didn't even enter :(

Url changed from http://www.iafrikan.com/2015/11/02/did-you-hear-about-how-sc..., which points to this.

Hi dang, the iAfrikan version is re-published, updated and edited with permission.

The site guidelines ask for original sources. But we'll make an exception in this case.

Reply on news.ycombinator.com