Note that the "cold fusion" debacle (1989 Pons & Fleischmann 1989) was fueled by a poor understanding of how to measure temperature and concentrations in an improperly stirred container. Friends at Bell Labs reproduced their electrochemical data by inadequate stirring of a beaker with the Pd electrodes. Using local temperature measurements and assuming uniformity generated the magic energy. Stirring "enough" is very hard. --R On Sat, Aug 31, 2019 at 7:28 PM Bill Gosper <billgosper@gmail.com> wrote:
Another observation: As the teapot|jar with that undissolved sugar starts to cool, stir it noisily with a spoon. As the sugar dissolves, the pitch of the tinkling declines rather dramatically. —rwg
On Wed, Mar 20, 2019 at 1:54 PM Bill Gosper <billgosper@gmail.com> wrote:
On Wed, Mar 20, 2019 at 11:37 AM <Shy respondent> wrote:
[just us]
I think you may just need to wait longer.
Yes.
If the water isn't stirred (either manually or by boiling) then the liquid near the sugar pile will be highly saturated and you'll have to wait for random thermal stirring to transport it away
But for several minutes, at least, the amount of dissolved sugar actually declines.
On 2019-03-20 12:17, Allan Wechsler wrote:
The obvious question, for me, is how are you measuring this process? I imagine that you could extract a cc of solution each minute, then evaporate them and weigh the amount of sugar in each. But I think you're probably not doing that, but rather relying on some kind of visual measure. What is the observed dynamic? Does it dissolve for a while until the concentration hits a plateau, and then sugar starts to precipitate out? Exactly! There's way more sugar in the bottom after it cools for a while. Huge density gradient from lack of stirring. You should have no trouble observing
this.
Unless I decontrolled it with a teabag of Stash Double Bergamot. —rwg
On Wed, Mar 20, 2019 at 1:57 PM Bill Gosper <billgosper@gmail.com>
wrote:
Dump a couple of Tbsp of sugar into a quart or two jar of tepid water. Don't stir. 𝜇wave a couple minutes, hot but not boiling. Let it sit.
Experimental
claim: The total dissolved sugar is not an increasing function of time, even though a couple of Tbsp is << enough to saturate even cold water. —rwg
On Mar 20, 2019, at 10:57 AM, Bill Gosper <billgosper@gmail.com>
wrote:
Dump a couple of Tbsp of sugar into a quart or two jar of tepid water. Don't stir. 𝜇wave a couple minutes, hot but not boiling. Let it sit.
Experimental
claim: The total dissolved sugar is not an increasing function of time, even though a couple of Tbsp is << enough to saturate even cold water. —rwg _______________________________________________
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