BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Biomedical Mathematics Group - ECPv6.17.3//NONSGML v1.0//EN
CALSCALE:GREGORIAN
METHOD:PUBLISH
X-ORIGINAL-URL:https://www.ibs.re.kr/bimag
X-WR-CALDESC:Events for Biomedical Mathematics Group
REFRESH-INTERVAL;VALUE=DURATION:PT1H
X-Robots-Tag:noindex
X-PUBLISHED-TTL:PT1H
BEGIN:VTIMEZONE
TZID:Asia/Seoul
BEGIN:STANDARD
TZOFFSETFROM:+0900
TZOFFSETTO:+0900
TZNAME:KST
DTSTART:20250101T000000
END:STANDARD
END:VTIMEZONE
BEGIN:VEVENT
DTSTART;TZID=Asia/Seoul:20261002T100000
DTEND;TZID=Asia/Seoul:20261002T120000
DTSTAMP:20260824T001413Z
CREATED:20260824T001413Z
LAST-MODIFIED:20260824T001413Z
UID:12985-1790935200-1790942400@www.ibs.re.kr
SUMMARY:Ptolemy's Equant Equates to a Universal Dynamical Clock via Machine Learning - Gyuyoung Hwang
DESCRIPTION:In this talk\, we discuss the paper “Ptolemy’s Equant Equates to a Universal Dynamical Clock via Machine Learning” by Jindong Zhang et al.\, arXiv\, 2026. \nAbstract: \nOscillatory dynamics arise ubiquitously in nonlinear systems\, yet identifying a physically interpretable phase and phase dynamics in nonlinear\, high-dimensional oscillations remains a central unresolved problem. Here we establish the principle of a universal dynamical clock\, a physical perspective in which oscillations of arbitrary dimensionality and geometry are equivalently represented as uniform rotation through an equant-induced nonlinear viewing coordinate\, inspired by Ptolemy’s equant and formalised through an areal-uniformity principle reminiscent of Kepler’s second law. Using a machine-learning framework\, we demonstrate the existence of such an equant for a broad class of oscillatory dynamics and construct the associated dynamical clock and phase dynamics under additive forces\, including noise\, periodic perturbations\, and coupling. Its value in uncovering new physical rules and phenomena is demonstrated by four findings: (i) collective oscillations in Escherichia coli populations obey a previously unexplained superlinear scaling law\, resolving a long-standing open problem posed in 2004; (ii) the response mechanisms of engineered genetic circuits to changes in gene expression and environmental conditions; (iii) a classical-mechanics counterpart of the Berry geometric phase emerges naturally from the phase of the dynamical clock; and (iv) optimal equant non-uniformity provides a geometric early-warning signal for critical transitions and enables prediction of critical parameters. By providing operational and system-agnostic phase dynamics that can be constructed directly from data\, the dynamical clock enables principled classification\, comparison\, and control of oscillatory systems\, and offers a new route to understanding how specific dynamical regimes support distinct functional behaviours in networked systems
URL:https://www.ibs.re.kr/bimag/event/ptolemys-equant-equates-to-a-universal-dynamical-clock-via-machine-learning-gyuyoung-hwang/
LOCATION:B232 Seminar Room\, IBS\, 55 Expo-ro Yuseong-gu\, Daejeon\, Daejeon\, 34126\, Korea\, Republic of
ORGANIZER;CN="Jae Kyoung Kim":MAILTO:jaekkim@kaist.ac.kr
END:VEVENT
END:VCALENDAR