{"id":6453,"date":"2026-10-19T09:48:55","date_gmt":"2026-10-19T09:48:55","guid":{"rendered":"https:\/\/phd.hi.is\/doktorsvorn\/doktorsvorn-i-efnafraedi-rohit-goswami\/"},"modified":"2026-10-19T09:48:55","modified_gmt":"2026-10-19T09:48:55","slug":"doktorsvorn-i-efnafraedi-rohit-goswami","status":"publish","type":"phd_defence","link":"https:\/\/phd.hi.is\/en\/doktorsvorn\/doktorsvorn-i-efnafraedi-rohit-goswami\/","title":{"rendered":"Doktorsv\u00f6rn \u00ed efnafr\u00e6\u00f0i – Rohit Goswami"},"content":{"rendered":"
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Streymi<\/a><\/strong><\/p>\n

Doktorsefni:<\/strong> Rohit Goswami<\/p>\n

Heiti ritger\u00f0ar: <\/strong>Skilvirk k\u00f6nnun \u00e1 gangi og hra\u00f0a efnahvarfa – \u00fer\u00f3un og hagn\u00fdting \u00e1 noth\u00e6fum Gauss ferlisl\u00edk\u00f6num (Efficient Exploration of Chemical Kinetics — Development and application of tractable Gaussian Process Models)<\/p>\n

Andm\u00e6lendur<\/strong>:- Dr. Sigur\u00f0ur I. Erlingsson, pr\u00f3fessor vi\u00f0 H\u00e1sk\u00f3lann \u00e1 Reykjav\u00edk
\u00a0Dr. Normand Mousseau, pr\u00f3fessor vi\u00f0 Universit\u00e9 de Montr\u00e9al, Kanada<\/p>\n

Lei\u00f0beinandi: <\/strong>Dr. Hannes J\u00f3nsson, pr\u00f3fessor vi\u00f0 Raunv\u00edsindadeild H\u00e1sk\u00f3la \u00cdslands<\/p>\n

Einnig \u00ed doktorsnefnd: <\/strong>
Dr. Egill Sk\u00falason, pr\u00f3fessor vi\u00f0 I\u00f0na\u00f0arverkfr\u00e6\u00f0i-, v\u00e9laverkfr\u00e6\u00f0i- og t\u00f6lvunarfr\u00e6\u00f0ideild H\u00e1sk\u00f3la \u00cdslands
Dr. Birgir Hrafnkelsson, pr\u00f3fessor vi\u00f0 Raunv\u00edsindadeild H\u00e1sk\u00f3la \u00cdslands
Dr. Morris Riedel, pr\u00f3fessor vi\u00f0 I\u00f0na\u00f0arverkfr\u00e6\u00f0i-, v\u00e9laverkfr\u00e6\u00f0i- og t\u00f6lvunarfr\u00e6\u00f0ideild H\u00e1sk\u00f3la \u00cdslands
Dr. Thomas Bligaard, pr\u00f3fessor vi\u00f0 T\u00e6knih\u00e1sk\u00f3la Danmerkur (DTU), Danm\u00f6rk<\/p>\n

Doktorsv\u00f6rn st\u00fdrir:<\/strong> Dr.Benjam\u00edn R. Sveinbj\u00f6rnsson, d\u00f3sent og varadeildarforseti Raunv\u00edsindadeildar H\u00e1sk\u00f3la \u00cdslands<\/p>\n

\u00c1grip<\/strong><\/p>\n

Stj\u00f3rnun efnakerfa \u00ed r\u00fami og t\u00edma til a\u00f0 hafa \u00e1hrif \u00e1 samverkandi efnahv\u00f6rf hefur veri\u00f0 markmi\u00f0 efnafr\u00e6\u00f0innar allt fr\u00e1 d\u00f6gum gullger\u00f0arlistarinnar. \u00cd dag er mat \u00e1 afur\u00f0um og hra\u00f0a efnahvarfa, \u00e1samt mati \u00e1 st\u00f6\u00f0ugleika efna og efnivi\u00f0a, grundvallarverkefni \u00ed efnai\u00f0na\u00f0i. \u00der\u00e1tt fyrir st\u00f6kk \u00ed st\u00e6r\u00f0fr\u00e6\u00f0ilegri l\u00edkanager\u00f0, me\u00f0 n\u00e1kv\u00e6mum l\u00fdsingum \u00e1 rafeindaskipan til a\u00f0 l\u00fdsa fj\u00f6leinda skammtafr\u00e6\u00f0ikerfum, og \u00fer\u00e1tt fyrir a\u00f0gengi a\u00f0 st\u00f3rauknu reikniafli (exascale), vantar enn skilvirkar a\u00f0fer\u00f0ir til a\u00f0 \u00e1kvar\u00f0a hvarfhra\u00f0a \u00ed st\u00f3rum hermunum. Bein hermun \u00e1 gangverki at\u00f3ma takmarkast af stuttum t\u00edmaskala og litlum lengdarkvar\u00f0a. N\u00fdlega hefur or\u00f0i\u00f0 hr\u00f6\u00f0 fram\u00fer\u00f3un \u00ed ger\u00f0 v\u00e9ll\u00e6r\u00f0ra m\u00e6ttisfalla (machine learned potential functions), en \u00fe\u00e6r krefjast st\u00f3rra gagnagrunna sem inntaks og eru ekki hagn\u00fdtar \u00feegar verkefni\u00f0 er a\u00f0 skima hratt \u00ed gegnum \u00fe\u00fasundir efna e\u00f0a efnivi\u00f0a til a\u00f0 finna bestu kand\u00eddatana fyrir t\u00e6knilega n\u00fdtingu. \u00de\u00e6r hafa ennfremur hinga\u00f0 til takmarkast vi\u00f0 sv\u00e6\u00f0i \u00fear sem at\u00f3min eru \u00ed st\u00f6\u00f0ugri uppr\u00f6\u00f0un og eru ekki \u00e1rei\u00f0anlegar fyrir hvarf\u00e1st\u00f6nd (transition state regions) sem \u00e1kvar\u00f0a a\u00f0 miklu leiti hvarfhra\u00f0ann. Tilraunir til a\u00f0 kanna hvarfanet \u00e1 sj\u00e1lfvirkan h\u00e1tt me\u00f0 n\u00e6gilegri n\u00e1kv\u00e6mni fela \u00ed s\u00e9r of h\u00e1an kostna\u00f0 vi\u00f0 reikninga \u00e1 rafeindaskipan. Einfaldandi n\u00e1lganir fyrir hra\u00f0a\u00fatreikninga gera r\u00e1\u00f0 fyrir \u00fev\u00ed a\u00f0 efnahv\u00f6rf s\u00e9u h\u00e6gir ferlar mi\u00f0a\u00f0 vi\u00f0 titring at\u00f3manna svo a\u00f0 varmalegt jafnv\u00e6gi n\u00e1ist og n\u00fdta \u00fev\u00ed t\u00f6lfr\u00e6\u00f0ilegar n\u00e1lganir fyrir \u00fatreikninga \u00e1 hvarfhra\u00f0a. \u00cd einf\u00f6ldustu n\u00e1lguninni, kj\u00f6rsveifilsn\u00e1lgun (harmonic approximation) vi\u00f0 virkjunar\u00e1standskenninguna (transition state theory), sn\u00faast \u00fe\u00e6r um a\u00f0 finna fyrsta stigs s\u00f6\u00f0ulpunkta \u00e1 orkuyfirbor\u00f0inu sem l\u00fdsir \u00fev\u00ed hvernig orka kerfisins er h\u00e1\u00f0 sta\u00f0setningu at\u00f3manna. Jafnvel \u00fe\u00e1 er reikni\u00fe\u00f6rfin vi\u00f0 leit a\u00f0 s\u00f6\u00f0ulpunktum of mikil \u00ed m\u00f6rgum tilfellum, s\u00e9rstaklega \u00feegar orka og at\u00f3mkraftar eru fengnir \u00far reikningum \u00e1 rafeindaskipaninni. Hr\u00f6\u00f0un \u00e1 s\u00f6\u00f0ulpunktaleit bygg\u00f0 \u00e1 sta\u00f0gengilsl\u00edk\u00f6num (surrogate models) hefur veri\u00f0 l\u00fdst sem v\u00e6nlegri \u00ed n\u00e6rri \u00e1ratug, en hefur \u00ed reynd veri\u00f0 h\u00f6mlu\u00f0 af mikilli yfirbyggingu og t\u00f6lulegum \u00f3st\u00f6\u00f0ugleika sem gera a\u00f0 engu \u00e1vinninginn \u00ed raunt\u00edma. \u00deessi ritger\u00f0 kynnir lausn sem byggir \u00e1 heildr\u00e6nni n\u00e1lgun \u00e1 \u00feessu verkefni sem sam\u00fe\u00e6ttir h\u00f6nnun \u00e1 e\u00f0lisfr\u00e6\u00f0ilegri framsetningu, t\u00f6lfr\u00e6\u00f0ilegu l\u00edkani og kerfisarkitekt\u00far. \u00deessi hugmyndafr\u00e6\u00f0i birtist \u00ed Optimal Transport Gaussian Process (OT-GP) umgj\u00f6r\u00f0inni, sem notar e\u00f0lisfr\u00e6\u00f0ilega me\u00f0vita\u00f0a (physics-aware) framsetningu bygg\u00f0a \u00e1 m\u00e6likv\u00f6r\u00f0um fyrir bestun flutnings (optimal transport) til a\u00f0 b\u00faa til \u00fejappa\u00f0an og efnafr\u00e6\u00f0ilega vi\u00f0eigandi sta\u00f0gengil fyrir st\u00f6\u00f0uorkuyfirbor\u00f0i\u00f0. \u00deetta skilgreinir t\u00f6lfr\u00e6\u00f0ilega trausta n\u00e1lgun og notar markvissa s\u00fdnat\u00f6ku til a\u00f0 draga \u00far reikni\u00fe\u00f6rfinni. Samhli\u00f0a endurskrifun \u00e1 EON hugb\u00fana\u00f0inum fyrir hermun \u00e1 l\u00f6ngum t\u00edmaskala, er sett fram styrktarn\u00e1msn\u00e1lgun (reinforcement-learning) fyrir l\u00e1gh\u00e1ttarfylgni (minimum mode following) a\u00f0fer\u00f0ina \u00feegar loka\u00e1stand er ekki tilteki\u00f0 og hnikateygjubands (nudged elastic band) a\u00f0fer\u00f0ina \u00feegar b\u00e6\u00f0i upphafs- og loka\u00e1stand eru tilgreind. Samanlagt marka \u00feessar framfarir n\u00fdja hugmyndafr\u00e6\u00f0i fyrir hermun \u00e1 efnahv\u00f6rfum sem byggir \u00e1 framsetningunni fyrst (representation-first) og er \u00fej\u00f3nustumi\u00f0u\u00f0 (service-oriented). \u00c1rangur \u00feessarar a\u00f0fer\u00f0afr\u00e6\u00f0i er s\u00fdndur me\u00f0 st\u00f3rum vi\u00f0mi\u00f0unarpr\u00f3funum sem s\u00fdna g\u00f3\u00f0a frammist\u00f6\u00f0u, greinda me\u00f0 l\u00edk\u00f6num Bayes. Me\u00f0 \u00fev\u00ed a\u00f0 \u00fer\u00f3a a\u00f0fer\u00f0 fyrir afkastamikil opinn-hugb\u00fana\u00f0ar (open-source) verkf\u00e6ri, umbreytir \u00feessi vinna g\u00f6mlu fr\u00e6\u00f0ilegu lofor\u00f0i \u00ed hagn\u00fdta t\u00e6ki til a\u00f0 kanna gang og hra\u00f0a efnahvarfa.<\/p>\n

\u00a0<\/p>\n

Um doktorsefni\u00f0<\/strong><\/p>\n

Rohit Goswami er f\u00e6ddur \u00ed Brookhaven, New York, \u00ed Bandar\u00edkjunum. Hann lauk B.Tech. pr\u00f3fi \u00ed efnaverkfr\u00e6\u00f0i fr\u00e1 Harcourt Butler Technical University \u00e1 Indlandi. A\u00f0 loknu starfi vi\u00f0 Indian Institute of Technology \u00ed Kanpur h\u00f3f hann doktorsn\u00e1m vi\u00f0 H\u00e1sk\u00f3la \u00cdslands. Undir handlei\u00f0slu dr. Hannesar J\u00f3nssonar, og me\u00f0 stu\u00f0ningi doktorsnefndar sinnar og samstarfsmanna, beindust ranns\u00f3knir hans a\u00f0 skilvirkum reikningum til a\u00f0 \u00e1kvar\u00f0a gang og hra\u00f0a efnahvarfa.<\/p>\n

\u00cd verkefni hans eru \u00fer\u00f3a\u00f0ar n\u00fdjar t\u00f6lvut\u00e6kar framsetningar (e. representations) til a\u00f0 skapa me\u00f0f\u00e6rileg og skilvirk Gaussian-ferlisl\u00edk\u00f6n. \u00deessi n\u00e1lgun hra\u00f0ar verulega reikningunum me\u00f0 \u00fev\u00ed a\u00f0 f\u00e6kka hversu oft \u00fearf a\u00f0 meta orku kerfisins og kraftinn sem verkar \u00e1 at\u00f3min. Samhli\u00f0a ranns\u00f3knum s\u00ednum hefur hann veri\u00f0 virkur \u00fe\u00e1tttakandi og teki\u00f0 a\u00f0 s\u00e9r \u00e1byrg\u00f0arhlutverk \u00ed samf\u00e9lagi opins hugb\u00fana\u00f0ar.<\/p>\n

Rohit starfar n\u00fana vi\u00f0 EPFL h\u00e1sk\u00f3lann \u00ed Lausanne \u00ed Sviss.<\/p>\n

Rohit f\u00e6rir fj\u00f6lskyldu sinni innilegar \u00feakkir fyrir \u00f3bilandi stu\u00f0ning, s\u00e9rstaklega eiginkonu sinni, Ruhi, foreldrum s\u00ednum, pr\u00f3fessor Debabrata Goswami og Sonaly Goswami. Einnig systur sinni, dr. Amritu Goswami, og eiginmanni hennar, dr. Moritz Sallermann, \u00e1samt d\u00fdrm\u00e6tum g\u00e6lud\u00fdrum s\u00ednum og pl\u00f6ntum.<\/p>\n<\/div><\/div>","protected":false},"featured_media":5871,"template":"","meta":{"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"default","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","ast-disable-related-posts":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"_phd_date_start":"2025-12-19T14:00:00+00:00","_phd_date_end":"2025-12-19T16:00:00+00:00","_phd_location":"Ver\u00f6ld - H\u00fas Vigd\u00edsar Stofa 023","_phd_admission":"A\u00f0gangur \u00f3keypis","_phd_thesis_title":"Skilvirk k\u00f6nnun \u00e1 gangi og hra\u00f0a efnahvarfa - \u00fer\u00f3un og hagn\u00fdting \u00e1 noth\u00e6fum Gauss ferlisl\u00edk\u00f6num (Efficient Exploration of Chemical Kinetics -- Development and application of tractable Gaussian Process Models)","_phd_source_url":"https:\/\/gamli.hi.is\/vidburdir\/doktorsvorn_i_efnafraedi_rohit_goswami","_phd_source_node_id":"442992","_phd_source_type":"vidburdir","_phd_member_id":995,"footnotes":""},"phd_school":[101,93],"phd_discipline":[102],"class_list":["post-6453","phd_defence","type-phd_defence","status-publish","has-post-thumbnail","hentry","phd_school-raunvisindadeild","phd_school-verkfraedi-og-natturuvisindasvid","phd_discipline-phd-i-efnafraedi"],"_links":{"self":[{"href":"https:\/\/phd.hi.is\/en\/wp-json\/wp\/v2\/phd_defence\/6453","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/phd.hi.is\/en\/wp-json\/wp\/v2\/phd_defence"}],"about":[{"href":"https:\/\/phd.hi.is\/en\/wp-json\/wp\/v2\/types\/phd_defence"}],"version-history":[{"count":0,"href":"https:\/\/phd.hi.is\/en\/wp-json\/wp\/v2\/phd_defence\/6453\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/phd.hi.is\/en\/wp-json\/wp\/v2\/media\/5871"}],"wp:attachment":[{"href":"https:\/\/phd.hi.is\/en\/wp-json\/wp\/v2\/media?parent=6453"}],"wp:term":[{"taxonomy":"phd_school","embeddable":true,"href":"https:\/\/phd.hi.is\/en\/wp-json\/wp\/v2\/phd_school?post=6453"},{"taxonomy":"phd_discipline","embeddable":true,"href":"https:\/\/phd.hi.is\/en\/wp-json\/wp\/v2\/phd_discipline?post=6453"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}