4 ms·
The 13.8Gy claim is made by estimating, calculating and then confirming by experiment how quickly wear and tear works (the primary mechanism is nanograting, and
by lvh 7y ago
The 13.8Gy claim is made by estimating, calculating and then confirming by experiment how quickly wear and tear works (the primary mechanism is nanograting, and the primary contributing physical quantity is temperature). It then specifically grabs 13.8Gy as an example data point because that's the age of the Universe, but they could've picked any other point on a time/temperature scale, like, say, "room temperature".
In what sense is this "not scientific"?
- modsiw 7y agoBecause they first chose the result they wanted — age of universe and worked backwards to derive that result. Is it true? Sure, probably. The method flys in the face of the foundations of science and was done for sensationalism. What’s special about 462K? Is it a local min/max? Doesn’t seem so.
- lvh 7y agoThey computed, verified and measured wear and tear (lifespan in Gy) as a function of temperature. The paper, which I linked, includes the full plot. They had to pick _some number_ (temp or years) in order to communicate it as one data point. There's nothing special about 462K -- it's what happens when you pick the age of the Universe as how long you want it to last form now. Pick a billion years, or 10 billion, and you get a different temp. Given that they had a hypothesis, designed an experiment and validated the result, it seems a bit much to say it "flys[sic] in the face of the foundations of science".
- AstralStorm 7y agoAnd finally the disc will never reach that, because it will not physically survive (or it's surroundings) to reach that time. Not on Earth, not in space, when real considerations like impact resistance are in.