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Posts tagged with reality

Playing around with polaroid screens at Google.

If you shine light through

  • a light polariser A
  • another light polariser B that’s perpendicular to A (i.e., A ⊥B or A×B=0)
  • i.e., AB represents “shine the light through A then through B which ⊥A
  • then no light comes through (it’s black.)

If you shine light through

  • a polaroid A
  • another polaroid B ⊥ A
  • a third polaroid C that’s halfway between A and B (either halfway)

then no light comes through (it’s black.)

So far, formulaically, we have:

  • AB=0
  • BA=0
  • whence it follows
  • ABC=(AB)C=(0)C=0
  • CBA=C(0)=0
  • BAC=0
  • CBA=0

But! This is surprising to watch and surprising to see the formula.

  • If you shine through A then C then B, it’s kind of light!
  • ACB≠0
  • furthermore
  • BCA≠0

Woo-hoo, Noncommutativity!

Earlier in the talk Ron Garret does a two-slit experient with two mechanical-pencil leads and a laser pointer. Wave-particle duality with an at-home science kit.

(Source: twitter.com)




  • "I wanted to be pissed about my breast cancer"
  • "They wanted to be angry about being laid off"
  • "It’s untrue that a positive attitude boosting the immune system increases the odds of withstanding cancer" "I have a Ph.D in cellular immunology"
  • Quantum physics become an excuse to mock all of science
  • "I didn’t come out of cancer more spiritual or a better person. If anything I’m a little meaner and more cynical"
  • There is no “real world”, there’s the real world through my positive mood and the real world through my bad mood.

Smile or Die by Barbara Ehrenreich




We Are Not Objects

  • @isomorphisms: I don't think "inheritance" from the object-oriented programming paradigm works to describe people in real life, for at least two reasons:
  • @isomorphisms: [1] @ISA versus "does". "Am I" a mathmo? This is like identifying someone with their career title, versus "I do maths" or "I'll be doing maths later today". "Am I" a writer? Or am I writing right now? Or do I write for 7% of my waking hours?
  • @isomorphisms: Something I notice as well talking to bourgeois youths. "Is a" entrepreneur. "Is a" gardener. "Is a" cook. Related to their division of life into career and "on the side".
  • @isomorphisms: Also twitter profiles. Some people list a lot of nouns or titles to describe themselves. I wrote a poem once; I started a business once. Does that make me @ISA poet or @ISA entrepreneur?
  • See also: [isomorphismes.tumblr.com/post/15409646048] -- what E.O. Wilson said about how we're all expected to play to defined roles & expectations -- Behave As Mother; Behave As Wife; Behave As Judge; Behave As Daughter [https://www.psychotherapy.net/article/parents].
  • @isomorphisms: [2] Maybe the more fundamental problem is that I'd want to pass *response functions* rather than properties. The idea that people respond to their circumstances rather than being determined by properties. "Am I" lazy with no ambition? Or don't see opportunities and thus don't work toward "growth"? "Am I" passionate about Ruby? Or did I come across the Ruby language and gradually get more and more into it, as a response to environment?




[T]he question of what “really” exists pervades the sciences and human thought in general.

The belief that the infinite does not really exist goes back at least to Aristotle. Parrnenides even questioned the reality of plurality and change. (Einstein’s vision has much in common with Parmenides). Towards the end of the nineteenth century an acrimonious exchange took place between Kronecker and Cantor regarding the reality of the actual (as opposed to potential) infinite. Kronecker claimed that only the finite integers really exist and all else is merely the work of man.

Cantor countered that the essence of mathematics was its freedom and that he had attained a larger vision than Kronecker had who could not see the infinite. Most mathematicians have followed Cantor and found his paradise a more beautiful and alluring universe.

…. But this seeing is not explained by modus ponens. In his beautiful book Proofs and Refutations, Lakatos (1976) has shown that the mathematical process itself is dialectical and not Euclidean. At all times our ideas are formally inconsistent. But inconsistency, while still recognized as a pathology, is no longer seen to be a fatal disease. If we come across a contradiction, we localize it, isolate it, and try to cure it. But we have to get over our neurotic phobias concerning this disease and recognize it as inseparable from life itself.




[E]veryone pretend[s] as if they were just giving one another gifts and then they fervently denied they expected anything back. But in actual fact everyone [understands] there [are] implicit rules and recipients would feel compelled to make some sort of return.

…. If I take a free-market economist out to dinner he’ll feel like he should return the favor and take me out to dinner later. He might even think that he is something of chump if he doesn’t and this even if his theory tells him he just got something for nothing and should be happy about it. Why is that?

This … shows there is always a certain morality underlying what we call economic life. …

[Marcel] Mauss didn’t really think of everything in terms of exchange; this becomes clear if you read his other writings besides ‘The Gift’….
For example, take hierarchy. Gifts given to inferiors or superiors don’t have to be repaid at all. If another professor takes our economist out to dinner, sure, he’ll feel that he should reciprocate; but if an eager grad student does, he’ll probably figure just accepting the invitation is favor enough; and if George Soros buys him dinner, then great, he did get something for nothing after all. In explicitly unequal relations, if you give somebody something, far from doing you a favor back, they’re more likely to expect you to do it again.
David Graeber

(Source: )




Proof that differential equations are real.

The shapes the salt is taking at different pitches are combinations of eigenfunctions of the Laplace operator.

(The Laplace operator  tells you the flux density of the gradient flow of a many-to-one function ƒ. As eigenvectors summarise a matrix operator, so do eigenfunctions summarise this differential operator.)

Remember that sound is compression waves — air vibrating back and forth — so that pressure can push the salt (or is it sand?) around just like wind blows sand in the desert.

Notice the similarity to solutions of Schrödinger PDE’s from the hydrogen atom.

When the universe sings itself, the probability waves of energy hit each other and form material shapes in the same way as the sand/salt in the video is doing. Except in 3-D, not 2-D. Everything is, like, waves, man.

To quote Dave Barry: I am not making this up. Science fact, not science fiction.