John Horton Conway Quotes

[L]attice packing... has the properties that 0 is a center and... if there are spheres with centers <math>u</math> and <math>v</math> then there are spheres with centers <math>u + v</math> and <math>u - v</math>... [i.e.,] the sets of centers forms an . In crystallography these... are... called s... We can find... in general <math>n</math> centers <math>v_1,v_2, ...,v_n</math> for an n-dimensional lattice... such that the set of all centers consists of the sums <math>\sum k_i v_i</math> where <math>k_i</math> are s.

FIN, the axiom that information can't travel faster than a finite speed, (that's where it gets its name from)... does not have that nice property. ...I can't disprove... that somewhere there isn't an as yet undiscovered way of transmitting information faster than... light. ...FIN ...follows from a symmetry principle that the laws of physics are independent of the coordinate frame ...If you're traveling ...at half the speed of light, you still have the same physics ...That symmetry principle ...that's been tested in countless ways, and that's ...why we believe FIN.

Neither of us could have done it without the other.

He'd been working with... Jim Ax for two decades on a theory that is now contradicted by... [our] . ...I admire Simon tremendously.

Physicists... have seen lots of instances of people... without... qualifications in physics, and presenting some... loony theory... and they don't read it. ...[W]e had this thing in mathematics once. People... thought they'd proved Fermat's Last Theorem... Eventually somebody did, but he was a... distinguished... high-powered mathematician. I'm... prepared for the fact... that physicists, especially ones that don't read our paper, don't believe it. They think it's just another... of those strange things. However, it's... better than that. ...I hope that the physicists stay and... learn something...

It's one of the things I most admire about Simon Kochen, my co-author, that... in August 2006, we'd been talking about this... for years... Suddenly the scales fell away, that had been obscuring the thing, and I said... "We've proved if we have free will, so do the particles" and he... said "Yes... this means that my stuff with Ax is all nonsense, doesn't it?"

[T]he strangest contribution of quantum mechanics to this discussion is the EPR paradox. ...That's an essential contribution to our theorem too. ...Despite the fact that information can't be transmitted faster than the speed of light, ...remotely separated events can be correlated ...and this is the content of our TWIN axiom, you can put two particles into a... singleton state... the angular momentum of the pair of particles is zero... [B]y the conservation of angular momentum... if you measure the angular momentum of this in any direction, then for the angular momentum of the other you get the negative answer, but... we're going to square it, that means... the squared component of spin is the same... [T]hese particles have been sort of hypnotized. If you ask... they will give the same answer... like I and my twin brother... [T]he funny thing is, even though the proves that the answers do not exist ahead of time, the equality of the answers can exist...

Laplace... wrote Mécanique céleste discussing the motion of the planets. ...[O]ne ...reason why ...determinacy got its ...impetus from the development of science, was that Newton's theory of gravitation ...was entirely deterministic. It left no room for freedom. ...Laplace, who did a lot of work on Newtonian ...theory says ...An intellect ...[or] intelligence, which knew ...where all the particles were at some moment and how fast they were moving, and so on, that every single thing could be known to that intelligence, provided a ...good calculator. ...It could reason out exactly what was going to happen in the future. ...It's the strongest ...assertion of determinism in the scientific literature. I don't believe it for one moment..!

Descartes' dualism... is explicitly contradicted by our theorem.

Why do we care about finding dense packing in n-dimensional space? ...This is an interesting problem in pure geometry. Hilbert mentioned it in 1900 in his list open problems... [T[he best packings... have connections... with other branches of mathematics. ...

Here's a particle, and I... direct my finger at it... and ask... What's it's spin in that direction? ...This particle is quantized. ...[I]t can only give two answers ...1 and 0. If I hadn't put that word squared in it could give three answers, 1, -1 and 0 ...Initially, it was... obvious... to believe that this concept existed before you measured it, but that was found not to be so. ...[W]hat the says is that it can't exist before you measure it... because there's no consistent set of answers to every question.

The classical... problem is... how densely a large number of identical spheres ([e.g.,] ball bearings...) can be packed together. ...[C]onsider an aircraft hangar... [A]bout one quarter of the space will not be used... One... arrangement... the face-centered cubic (or fcc) lattice... spheres occupy <math>\pi / \sqrt{18} = .7405...</math> of the total space.... the lattice packing has density <math>.7405...</math> . [H]pwever, there are partial packings that are denser than the face-centered cubic... over larger regions...

I find it... fantastic that somebody 2,000 years ago could have suggested that atoms... have free will.

One consequence of the ... plus the assumption we actually have free will, is that even in the... inanimate world of particles, it's not true, this . A particle does one thing or another, and there's no reason... There's nothing in the previous history of the universe which tells it what to do.

SPIN and TWIN are operationally definable... Do the operation that's called, measuring... as many times as you like, and see that they always give the same answers. That's what is meant by saying that those things are operationally definable...