How Long Is A Piece Of String?
Alan Davies discovers that answering that question is much harder than he originally thought after visiting mathematician Marcus du Sautoy to help him find an answer. However, this creates more questions, which requires a trip to a place dedicated to measurement, the National Physics Laboratory. Finding out the exact length of the string proves even more troublesome when Marcus proposes the string could be infinitely long, thanks to the theory of fractals. After leaving Marcus, Alan visits a physics teacher to see if measuring the string in atoms can help him find an answer. However, this means exploring Quantum Mechanics. Alan goes to a lab to explore the theory of Quantum Mechanics in more detail to see if his string can be in two places at once, confusing him even further. Still no closer to an answer Alan is introduced to the theory that his string may have multiples lengths at the same time, all with the help of a stuffed cat. Alan doesn't believe Quantum Mechanics is important on a basic scale, but photosynthesis and the ability to smell might just change his mind. If Alan was to find the most accurate way of measuring his string he could theoretically create a black hole. Trying to find the solution to this question has been a philosophical journey for Alan, but he still visits Marcus du Sautoy to tell him his personal answer.
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comment #4150 Erin
the guy at the end his laugh is sooo aweful
reply | permalinkcomment #3758 The Tay
This is a reply to comment #3742
i agree with that whole heartedly. and this is a common thing with most docs. they tend to be made by people who mean well, and even have visionary intentions, but sometimes the simple facts fall through, however well informed or researched they are. its probably going to be that way until brad pitt, or megan fox signs on to host one or two (you know...budget). its kind of sad, really. these kinds of educational, and entertaining docs are almost the food for the intellectual masses. its what build, and bolsters the ranks of the scientifically interested.
reply | permalinkcomment #3742 Anon
This is pretty good for a documentary aimed at laypeople, but one thing bothers me no end. Electrons do not ORBIT the nucleus of an atom. That is the bohr model of the atom and was proven wrong in the 1920s, but most people still think it's true because a lot of teachers - like the physics teacher in this doco who agreed that they do orbit the nucleus - think that it's simpler and easier to understand, as if laypeople are too dumb to understand what's actually going on, and other teachers were taught the old model and don't themselves know of the new one. When drawn, btw, the new model looks more like this -> http://web.rollins.edu/~jsiry/atom-quantum.jpg. The electrons zoom around, being both particles and waves, spending most of their time in those dumbbell shaped spaces, which are the orbitals. The highest energy electrons, rather than those on the outermost orbit in the bohr model, are the valence electrons.
reply | permalinkcomment #3670 aj
shrodinger was autrian ;)
reply | permalinkcomment #3639 Rossman
Interesting subject, really makes you think about what everything is made out of...
reply | permalinkThe guy is not really funny though, at times he comes off as a little dense.
comment #3636 Tiago C.
Although infinity "both ways" raises some serious issues.
reply | permalinkIf the space between me and the nearest wall is infinite then how the hell am I able to reach it?
comment #3620 sher abbas
great documentary about the basic measurement
reply | permalinkgiving the idea,
THERE ALWAYS A PLENTY OF SPACE AT THE BOTTOM
comment #3596 dwyane shaw
very good. I kept expecting to here some conjecture on Zeno's Paradox's, and was pleasently surprised when they avoided it.
reply | permalinkI like these doc's that explain complex concepts in simple terms. But its a little disheartening when I still can't quite grasp it
comment #3581 Falcon Heene
I liked this documentary quite a bit.
reply | permalinkSeth Lloyd is now my new favorite scientist.
comment #3573 Jason
Fairly good doc. The best bits were at the end where quantum mechanics in nature was discussed. I definitely want a ruler that measures in ancient units now too. lol
reply | permalink