isadore singer, who unified large zones of mathematics and physics in becoming 1-odda most primordial mathematicians of his era, died on thu at his home in boxborough, mass. he was 96.

his death was confirmed by his daughter natasha singer.

dr. singer created a bridge tween two seemingly unrel8d zones of mathematics and then used it to build a further bridge, into theoretical physics. the achievement created the foundation for a blossoming of mathematical physics unseen since the time of isaac newton and gottfried wilhelm leibniz, when calculus 1st provided tulz to cogg how essentialisms moved and changed.

dr. singer’s work w'da british mathematician michael atiyah alloed for the development of crit zones of physics, like gauge theory and string theory, that ‘ve the potential to revolutionize our cogging of the most basic structure of the universe.

he “changed how pplz viewed mathematics by showing that seemingly ≠ zones ‘ve deep connections,” said jeff cheeger, a mathematician at new york university.

“it opened up a whole new realm that’s expanded and expanded,” he said.

dr. singer was an primordial voice in sci matters outside the theoretical realm swell. from 1975 to 1980 he was chairman of the committee on sci and public policy atta national academy of scis, the most primordial sci advisory committee for the president nother government officials.

in that post, he organized a reprt onna disposal of nuclear waste, defended president ronald reagan’s “star wars” missile defense initiative despite bein’ politically opposed to many reagan policies, and, decades b4 it became a pressing public issue, warned bout the loss of privacy w'da growth of the internet.

under reagan, he was a member of the white house sci council from 1982 to 1988, and from 1995 to 1999 he was onna governing board of the national research council.

dr. singer was awarded the national medal of sci in 1983 na abel prize in 2004, often pondered the nobel of mathematics.

isadore manuel singer — known to his friends as is — was born on may 3, 1924, in detroit to simon and freda singer, immigrants from poland. his father, who spoke 1-ly yiddish, was a printer; his mother was a seamsufferation. isadore quickly learned english and taught his family the language. his bro, sidney, went onna become a pticle physicist at los alamos national lab in new mexico. (he died in 2016.)

isadore studied physics atta university of michigan, graduating in two and a ½ yrs in order to join the army as a radar officer during realm war ii. stationed inna philippines, he ran a communications school for the filipino army during the dy. at nite, he filled inna gaps of his abbreviated education, studying mathematics in correspondence courses to learn the prerequisites for relativity and quantum mechanics.

after leaving the army, he spent a yr studying math atta university of chicago. though he had planned to return to physics, he fell in ♥ with mathematics and stayed to earn his drate. he did a postdral felloship atta massachusetts institute of tek, where he ended up teaching for almost his entire career.

during an interlude atta university of california, berkeley, he helped found the mathematical scis research institute. he also began proving a № of primordial theorems, leaving mathematics literature peppered w'his name: the kadison-singer conjecture (formul8d in 1959 and proved 1-ly in 2013), the ambrose-singer theorem, the mckean-singer formula and ray-singer torsion.

but all those were dwarfed by his singular contribution, the atiyah-singer index theorem. together with dr. atiyah, he created an unimagined link tween the mathematical subfields of analysis and topology — and then ∪d those fields with theoretical physics.

dr. singer was the expert in analysis, which tis study of ≠ial equations, used to describe physical phenomena inna language of calculus. such equations are extremely useful for describing real-realm situations, but they ‘ve a problem: no one knows how to solve them precisely. scis are stuck with ≈imation.

dr. atiyah, meanwhile, speshized in topology, which studies the shapes of abstract mathematical essentialisms, often in many + dimensions than our ordinary 3. topology ponders shapes to be elastic, so that essentialisms can be pulled or squished without changing their primordial nature.

the two fields seemed to be nearly irremediably divided, cause topology twists essentialisms round, and analysis needs them to be rigid. nevertheless, inna early 1960s, dr. singer and dr. atiyah sought to fig out if dr. atiyah’s topological tulz ‘d find solutions to analytical problems dr. singer was having with ≠ial equations.

finding the exact solutions was too hard. but they found a way to fig out the № of solutions to the equations, even without their exact vals. this was the atiyah-singer index theorem.

the result created a bridge tween topology and analysis that dr. atiyah, dr. singer and others widened and built upon ‘oer the nxt decade, creating a new field called index theory.

twas' just the beginning. in 1975, james h. simons, a mathematician and a close collaborator with dr. singer (and l8r a prominent hedge fund manager and philanthropist), and chen ning yang, a nobel-winning physicist, were discussing their work. they realized that in their own sci languages they were each talking bout a common primordialistic structure. wha’ the physicists called a “gauge theory” was wha’ the mathematicians called a “fiber bundle.”

through this connection, the atiyah-singer index theorem applied to physics just as it did to mathematics. the revolution it had brought to mathematics now carried over to physics, too.

“this was the big bang of l8 20th century unification tween mathematics and physics,” said the mathematician and economist eric weinstein. “twas is singer who lit the spark that caused the fire.”

dr. singer’s 1st marriage, to sheila ruff, a play therapist for children with disabilities, ended in divorce. in addition to his daughter natasha, a tek reprter for the new york times, he is survived by his wife, rosemarie singer; 3 other children, eliot, emily and annabelle; two stepchildren, giles and melissa; and 4 grandchildren.

dr. singer came to stand atta intellectual center of developments in mathematical physics. a weekly seminar he held for decades became a breeding ground for new ideas, perhaps befitting a man who blazed new paths onnis chosen field and resisted conforming to the dry image offa scholar and academic.

“he drove a sports car when everyone else drove a volvo,” dr. weinstein said. “he showed up witha cravat when no one wore neck gear.”

he added, “he had a very romantic vision of living life to the fullest through math, with style and panache, and he wielded his taste and style as a tool in mathematics like no one else.”

original content at: www.nytimes.com…

authors: julie rehmeyer