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>> The researchers ran a simulation based on two assumptions: that the planets' orbits were approximately circular, and that their orbits weren't at an angle relative to one another.

Original article

So no, it's not the complicated proper math. They really should have been able to find the closed form solution. However, the lead author is a grad student who is apparently Python happy, so...

https://physicstoday.scitation...

Interesting work with the best message to get out of this; don't rely on what's obvious, test what you think is true.

I'm not even sure what your point about potassium is. Eating a banana does not increase your potassium 40 exposure. This is true whether you use the linear-no-threshold model or not.

As for Thorium cycle reactors, yes, I agree that it's wise to be somewhat skeptical of the technology until some of the details are a bit more developed. The old IAEA report gives some of the basics: https://www-pub.iaea.org/mtcd/... , and there are review papers here and there that give a somewhat more updated view: https://aip.scitation.org/doi/... , for example.

I think it's an interesting enough approach to solving long-term problems that I would like to see some engineering development work done on a prototype to show it's feasible, but I wouldn't want to commit to it without seeing some engineering. There is not a "then a miracle occurs" step, but as with most engineering, the devil is likely to be in the details, and we need to know the details.

In the short term, though, my approach would be to start reprocessing spent reactor fuel. The proliferation concerns can be addressed, and it's simply silly to warehouse it in swimming pools; that's not reasonable by any possible metric.

... when quantum computing is capable of breaking current encryption, that same computer will be providing unbreakable encryption.For example:

. A. Ekert, “Quantum cryptography based on Bell’s theorem,” Phys. Rev. Lett.0031-9007 https://doi.org/10.1103/PhysRe... 67, 661–663 (1991). Google ScholarCrossref, CAS

Too bad you didn't look it up, because that isn't quite true. In the US, CO2 emission has been trending downwards for the last few years. While this is primarily due to natural gas use this is also due to the use of wind and solar power (which combine really well with natural gas since gas plants have very fast spin-up times) and more efficient cars. See https://www.technologyreview.com/s/601415/carbon-dioxide-emissions-keep-falling-in-the-us/. And two years in a row, global CO2 production declined http://physicstoday.scitation.org/do/10.1063/PT.5.1067/full/. So no, we are actually succeeding, not as fast as we need to, but the general trend is in the right direction. We can solve this, but if people keep falsely claiming that all we can do is mitigation then we're going to be in very bad shape. Moreover, the budgets for mitigation have been tiny in many locations.

Yeah, that never happened.

"Yeah, that never happened" is correct! Anonymous Coward says something accurate for a change.

There was no scientific consensus nor prediction by scientists that the Earth was "entering a global cooling phase."

Citations: http://journals.ametsoc.org/doi/pdf/10.1175/2008BAMS2370.1
http://physicstoday.scitation.org/do/10.1063/PT.5.8199/full/
https://www.scientificamerican.com/article/how-the-global-cooling-story-came-to-be/
http://www.realclimate.org/index.php/archives/2005/01/the-global-cooling-myth/"
http://www.factcheck.org/2015/03/cruz-on-the-global-cooling-myth-and-galileo/

Climate scientists were right then, but it's because most of them were ignoring the global cooling bullshit:

http://physicstoday.scitation....

Destructive aeroelastic flutter is an _example_ of resonance.

No it's not - there is no oscillating force driving the system at a particular frequency which is what always used to confuse me when I was a kid and we learnt it at school. While the results may look the same aeroelastic flutter is a self-excitation which is fundamentally different from a forced resonance. It's only a "pedantic distinction" in the same way that differentiating between mass and weight is a pedantic distinction. In most everyday situations in the Earth's approximately constant gravitational field, they may seem effectively the same but they are fundamentally different quantities.

Lastly my source is not Wikipedia: have a look this paper from 1991 which is in a referred journal (although one aimed at physics education, not research).

Changing the frequency of your thermal radiation a bit will not make a meaningful difference in cooling.

It is a bit backwards to phrase this as "beaming heat into cold space" rather than "reflecting most incoming ambiently-produced IR radiation while selectively emitting radiation in a same band we absorb" This doesn't seem to be the fault of journalists, it's phrased that way in the paper. This article avoids using that semantic.

Were they to allow the wavelengths re-emitted by the general environment outside, you'd get an offsetting absorptive heat gain. They could likely get the same effect at different wavelengths, but choosing this wavelength means basically no heat gain from atmospheric emission. There could even very well be a better choice of wavelength based on whatever materials the ground is made up of, but that could vary.

This article takes advantage of a definition for "terahertz band" as indicated in the paper linked.

http://aip.scitation.org/doi/f...

The "terahertz" band is 300 GHz to 10,000 GHz, so anyone who does work at 300 GHz is working in the "terahertz" band. However, the SI terahertz unit is 1000 GHz, as another poster pointed out. So this is on the far far far low end of the terahertz band. It's like claiming you're flying when you run, because both your feet are off the ground at the same time...