Trinity College experiment succeeds after 69 years
rte.ie
rte.ie
Am I the only one who finds this insulting? They could at least name the guy!!!
The one variable that could be controlled is the gravitational force on the substance. If we were on the moon the experiment, as designed, would take far longer to produce a drop. By using a centrifuge they could have easily simulated significantly greater gravitational forces and arrived at a result much sooner.
EDIT:
The Queensland experiment data says that it takes about 13 years for a drop to form and fall [1]. You'd need less than 5,000 g's to make it happen within a day or about 160 g's to get results in 30 days.
[1] http://www.nature.com/news/world-s-slowest-moving-drop-caugh...
Here's an interesting resource:
http://www.endmemo.com/bio/grpm.php
Now, there might be reasons why a million g's might be a bad idea. Maybe 100K g's is a better choice. Someone with more expertise in centrifuge application could chip in and clarify this.
Not really. You'll disintegrate in strange ways based on the relative density of your constituent parts.
<edit>: Another thought is that if you laid on a bed for 13 years (the time it took for a drop of pitch to form) without moving --ignoring tissue decay and other factors-- you'd probably "flow" just as you might in a high gravity environment. Gravity, like rust, never sleeps. </edit>
Yet, unless a domain expert says otherwise, I think your point is absolutely valid. However, pitch might just be the kind of substance that would be fine at a million g's. I don't know.
That's the reason for my request for comment from someone with centrifuge experience. At a million g's a lot of seemingly strange things can happen. However, perhaps 100, 1000 or 10,000 g's is reasonable. I used the million g example as an illustration of the attainable extreme in response to a comment that spoke about 6 or 7 g's. Clearly we can do better, far better.
In consultation with a domain expert (Chemist?) I would design the experiment to give results in somewhere between a day and a month. Faster if possible. The criteria would be to choose an acceleration that does not fundamentally change the nature of the substance under test. All we want to do is promote faster flow.
Pitch is a suspension. The heavy stuff would drop to the outside, the viscosity would be affected, no experiment.
This is unlikely, however. Many suspensions have a critical pressure below which they simply will not settle. Homogenized milk, for a familiar example.
The last bit is puzzling: Are all suspensions fluids? And all fluids are viscous (even non-newtonian)?
If so, why do we need an experiment to prove that pitch --a suspension-- is a fluid and is viscous?
On the point of using a centrifuge. Is there something particularly special about gravity on earth that does not affect pitch? In other words, if we exposed pitch to 0.1x, 1x, 10x, 100x and 1000x g, at what point would the fundamental characteristics of the material invalidate the experiment. Are fluids and their viscosity only defined on earth (ignoring thermal and other non-gravitational effects)? Perhaps pitch is a viscous fluid on earth but a solid on the moon, where gravity is 1/6 of ours?
Is this experiment only valid at 9.8 m/s^2 then? What's the tolerance based on the substance under test?
Pitch can be proven to be a suspension via distillation. To prove it's a fluid, it must be observed to flow, to form a droplet, and to detach that droplet in the manner of a fluid.
However:
> No, all suspensions are not fluids.
Interpreting what you said literally would imply that anything that is a suspension is definitely not a fluid. And I know one can interpret what you said according to common sense to deduce that you didn't mean that, and that since some suspensions definitely are fluids, then you must have meant that there are suspensions that are not fluids.
But this is about science, and where possible, I believe we should be precise.
I believe it matters.
Unfortunately, languages don't always work the way that logicians would like them to do. Yes, we can read that sentence as the English-language summary of a logical formula (something like ∀x [Sx -> ¬Fx]), but English (and many other languages) treat the scope of the "not" as ambiguous. It's not a matter of "interpreting what you said literally", because there are multiple correct literal interpretations of what he said---he is not using a metaphor or anything. There are many cases where "not" can scope out to an enclosing quantifier (one of the better-known is "All that glitters is not gold", famously by Tolkien), and this is not just because all these speakers are in error.
[0] Also computer scientist, but I'll wear my linguist hat for now.
A sentence like "all X are not Y" naturally associates like "all X are (not Y)". Usually modifiers attach to the closest thing they can, as a matter of well-established convention. So if someone decides they want that to mean "not (all X are Y)" and expects me to understand it, I'm going to go ahead and say they're the one in error. Sorry, Tolkien.
[0] Is that a word? Chromium spell-check doesn't like it. I have lightened up on neologisms, as long as it's clear what they mean.
Unfortunately, technically inclined people like to apply their domain specific "knowledge" (compiler cosntruction?) to everything and come to incredibly bad conclusions. Ex falso quodlibet.
It gets especially bad when technical guys talk about law and juristic methodology. Demonstrated daily here on HN.
[1] BTW, linguistics is descriptive, not prescriptive. You immediately disqualify yourself from any linguistic discussion when you claim that native speakers are in error.
Note: science is not about your opinion.
> unambiguity is essential
Is it? We function in the presence of ambiguity all the time. Sometimes, we let the ambiguity ride. Sometimes, we take a sentence that is (by itself) ambiguous and let the context disambiguate it. Sometimes, we use the ambiguity for some rhetorical purpose and then resolve it later. There are many sources of ambiguity in natural language---it's one of the things that makes NLP so damn hard---and you can't wave that away by saying that everybody is doing it wrong. (Not that generations of prescriptivist grammarians haven't tried.)
> Usually modifiers attach to the closest thing they can, as a matter of well-established convention.
First of all, attachment ambiguity is a difficult NLP problem specifically because modifiers don't always attach to "the closest thing they can". Second, to the extent that the statement is true (that low, i.e. "closer", attachment has a higher prior probability than high attachment), it is not a matter of "convention" but a fact about the grammar of a language. Third, "not" is special in all sorts of ways (as is negation in general, in many languages, not just English), and as I mentioned before, this specific kind of ambiguity is well-known, and interesting because it seems so strange, and once again you can't just wave the logic stick and declare that it ought not to be so.
My answer was "No, all suspensions are not fluids". The structure depended from the phrasing of the question.
Not all X are Y.
Some X are not Y.
We could apply some higher acceleration for a shorter time, but that acceleration would have to be highly consistent, and there is no way to shorten the experiment enough to keep that equipment from being unproductive to even contemplate.
Sometimes patience really is the best answer.
So I read that asphalt is actually a colloid and that pitch is not the same as asphalt. The Wikipedia page on pitch [3] says it is a "viscoelastic polymer".
So I have to ask. Can a polymer be a suspension or a colloid on its own or is pitch a polymer colloid in another "host" substance?
[1] http://en.wikipedia.org/wiki/Suspension_(chemistry)
[2] http://en.wikipedia.org/wiki/Asphalt
However, there are many suspensions which will never settle under standard gravity, but which will rapidly settle in a centrifuge. We call these colloids.
edit: also, the Earth's gravity might become a problem.
In Australia, they give you 3 years (plus an additional 1/2 year extension, which isn't always granted). After that, you're on your own, and many people get a full time job to support themselves.
I've seen quite a few people abandon their PhD because of the need to pay the bills once their funding runs out. It's quite sad.
'liberal arts' doesn't have a meaning in Australia, but I'm not aware of PhD applications being treated differently in different fields (or rather, the rules differing)
GP is pointing out that there are two experiments underway.
Check the video and notice that the suspended vessel jumps about 2 inches higher just after the drop.
It's a good recording, but I'm looking forward to a better one in 2026.
Bwahahahah!
Sometimes "silly" experiments can have value. I chatted with a physic prof once who said the very first experiment he did after gaining tenure was to investigate the isotropy of the universe in particle accelerator experiments -- in other words, do the laws of physic work the same way when the accelerator is pointed one direction, relative to distant stars, as any other.
Obviously, the likely result would be nada.
However, if he found something, it would be two possible things: (1) He was going to earn an instant Noble prize, or (2) There was a potential subtle systematic design error particle physicists had overlooked -- knowing how to look for this error and/or correct for it could have value.
#2 was more likely. But why not?
That was the most interesting thing I found in this experiment.
It honestly wouldn't surprise me in the least if the experiment was initiated knowing full well it would take decades to complete but they went ahead anyway 'for the craic'.
It sounds like the experiment, as designed, reached a conclusion in far less time than 69 years. It just took 69 years for someone to think about video taping it.
Maybe it was a badly planned experiment (or more likely, the cost/availability of cameras in those days prohibited their inclusion in the plans). Nevertheless, no firm conclusion can be drawn that the experiment could have been ended early, those previous "drips" may not have happened without external forces applied and so even if cameras had been used it may not have ended until now. Its probably likely that it would have ended had cameras been available, but the scientific method generally calls for a greater degree of certainty than "probably likely" before calling an experiment a success.
And of course, it is called an "experiment", not a "certainty". Mistakes happen and they're not always optimal, that’s all part of the fun of science!
...or maybe the video camera just got jostled when all scientists started dancing around in their glee =)
Or they got bored and cheated. 50/50 really.
"...the Pitch Drop Experiment is so slow, you can watch it for hours (check out the live cam) and not detect the slightest movement. But that doesn't mean nothing's happening. Professor John Mainstone tells us about his desperate attempts to catch the flashes of action hiding inside this decades-long experiment."
Decade-scale experiments aren't hard, but they do require planning.
I guess you could have asked that if you find a tree that's fallen in a forrest, did it actually fall over if no one saw it?
I'm sure the issue, if indeed there is one, is with the reporting not the scientists though.
D'OOOH... WERNSTROM!!!