Excerpts from
AIP Oral History Interview - January 9, 10 & 18, 2016
Robert P
Crease Crease:
Oh, right. ok. And now you do another sixth-order radiative correction paper.
Kinoshita:
Yeah.
Crease:
Paper 53.
Kinoshita:
And this was my graduate student.
Crease:
How do you pronounce it?
Kinoshita:
Cvitanović.
Crease:
Cvitanović, oh.
Kinoshita:
And this is the beginning of the serious g-2 work.
Crease:
Why do you describe this as serious as opposed to the other papers?
Kinoshita:
Because the other papers were approximations. These are all
approximations. You cannot be serious. So is this. If you use the
renormalization group technique, you only calculate the leading term,
not the complete calculation. But this is the beginning of a complete
sixth-order calculation. And he was a very good student.
Crease:
Where was he from?
Kinoshita:
From Yugoslavia, or whatever that…
Crease:
Where is he now?
Kinoshita:
He’s at Georgia Tech or someplace in mathematics. After writing this
paper and a few more papers on physics, he decided not to work on
physics. [pause] To work this, we wrote several papers with Cvitanović.
These are all different parts of the same problem.
[... later...]
Kinoshita:
[...] But experiment is better than 10%. And so, you have to
do eventually the exact calculation to all the sixth-order terms. That’s
what I did. By that time, I said—I did a few more diagrams with
Brodsky, but he had something else to do, so I took care of all the
remainder. In particular, I had a very good student, and he was
responsible for filling out how to do the sixth-order in a numerical
way.
Crease:
Who was that student?
Kinoshita:
I just [laugh] need to remember. Cvitanović.
Crease:
Cvitanović, oh yes.
Kinoshita:
And then after—many years after, we solved numerically the
sixth-order problem, not only the light-by-light, but all the terms,
with the help of Cvitanović
[... later...]
Kinoshita:
You see, when we did the sixth-order with Cvitanović, algebra
formulation was general enough you can apply to any order. So, the
[inaudible] was already sort of set up. So, going from sixth-to
eighth-order theoretically there was no roadblock to worry about except
that it was a much bigger problem [laugh] and you needed much bigger
computers. [...] I wouldn’t do any
calculation unless some experiment has come out with a challenge, a new
measurement and so on. At this time, when I finished the sixth-order, I
thought that was the end of my calculation of g-2 because it was better
than the experimental result coming out of Michigan.
[... later...]
Kinoshita:
Yeah. But anyway, this was at the international conference at Tbilisi in 1976.
Crease:
Tbilisi, yeah.
Kinoshita:
I was attending the conference, and then a guy named Lowell Brown at
the University of Washington told me that I had to get busy again
[laugh] because Dehmelt was doing a new experiment using a Penning trap
which was three orders of magnitude more accurate than the [inaudible]
precession experiment at Michigan. And Dehmelt, a few years later won
the Nobel Prize for that work. So, that’s why I started the
eighth-order. Or no, let’s see is that eighth-order or tenth-order? I’m
not quite sure. Tenth-order essentially I start around year 2000, so
later than that. So, must be eighth-order.
[... later...]
Ok, anyway, so
Lindquist started on the eighth-order and because of Lowell Brown’s
information that Dehmelt was now setting up a new experiment or he was
getting new results which were three orders magnitude better. So, the
eighth-order has to be done. That’s why [laugh] I did it. And as I said,
the machinery for eighth-order was already available due to the work of
Cvitanović in the sixth-order. So, that was not a big problem. The
computer at Cornell was never as good as I wished, so I used some
national computers at San Diego or someplace. But anyway, the
requirement for the computer at that stage was not really big, and so we
could get some preliminary results fairly quickly. But then when
Dehmelt’s result came out, certainly I wanted to do the next order, the
tenth-order, because the tenth-order can be as big as the contribution
of the eighth-order. [...]
Rashômon (what I remember)
Perturbative QED - Flying to Brookhaven with box-fulls of cards - and why did I do this? - Gauge invariance is the bane of my life - Finite QED
