He says it didn't happen. And besides, it happened a long time ago.
25 Jan 2010, died on Saturday at 85. His obituary in the NY Times includes this paragraph:
Working in three dimensions, Mr. Chermayeff designed the sidewalk sculpture — an immense number 9 in red steel — that marks the entrance to 9 West 57th Street in Manhattan. The building, by Gordon Bunshaft of Skidmore Owings & Merrill, is noted for its convex facade that glides down to street level.Well. 9 W 57 is concave, not convex. (You could argue that any concave surface is convex when regarded from the other side. But a façade is generally apprehended from without, no?) Obligatory screenshot here in case the Times fixes* their page.
On 19 May 2011, I wrote about metastability, defined by Wikipedia as "the ability of a digital electronics system to persist for an unbounded time in an unstable equilibrium or metastable state." Metastability rears its intractable head when (for example) a system has to decide which of two events happened first. See also Buridan's ass.
Bitcoin's blockchain system is subject to metastability. Each Bitcoin miner that strikes paydirt adds a new block to the blockchain and announces it to the network. Should two miners extend the chain at about the same time, the distributed database may fail to reach consensus as to who was first. As described in the original Bitcoin paper, the can is kicked down the road:
If two nodes broadcast different versions of the next block simultaneously, some nodes may receive one or the other first. In that case, they work on the first one they received, but save the other branch in case it becomes longer. The tie will be broken when the next proof-of-work is found and one branch becomes longer; the nodes that were working on the other branch will then switch to the longer one.That works unless two miners again succeed at about the same time. In practice these disputes are resolved before too long but there is no guarantee of how quickly resolution will come.
* It's fixed as of 11 Dec 2017 (tacitly, i.e. without a correction notice) Because Planck's constant is so small, it's easy to think of Heisenberg's uncertainty principle being relegated to phenomena occurring on too tiny a scale to observe in everyday experience. But there are noticeable effects that show the principle at work.
Photographers take diffraction into account when choosing lens aperture. The smallest aperture settings on most lenses don't give the sharpest pictures because of diffraction. This is an instance of the uncertainty principle: the more the iris confines the position of photons passing through a lens, the less predictable the photons' momentum. In particular, the direction of photons' momentum is uncertain and fewer of them go where you're trying to focus them. Pic from this morning.
Projective test: what do the clouds remind you of?
Mouseover the image for my answer.
photo by Kira Od