Editing Timeline of classical mechanics (section)

== Analytical mechanics ==
* 1788 – [[Joseph-Louis Lagrange]] presents [[Lagrangian mechanics|Lagrange's equations of motion]] in the ''Méchanique Analytique''
* 1798 – [[Pierre-Simon Laplace]] publishes his [[Traité de mécanique céleste]] vol.1 and lasts vol.5 in 1825. In this, he summarized and extended the work of his predecessors
* 1803 – [[Louis Poinsot]] develops idea of [[Angular momentum#Conservation of angular momentum|angular momentum conservation]] (this result was previously known only in the case of conservation of [[areal velocity]])
* 1813 – [[Peter Ewart]] supports the idea of the conservation of energy in his paper "On the measure of moving force"
* 1821 – [[William Rowan Hamilton|William Hamilton]] begins his analysis of [[Hamilton's characteristic function]] and [[Hamilton–Jacobi equation]]
* 1829 – [[Carl Friedrich Gauss]] introduces [[Gauss's principle of least constraint]]
* 1834 – [[Carl Gustav Jacob Jacobi|Carl Jacobi]] discovers his [[Jacobi ellipsoid|uniformly rotating self-gravitating ellipsoids]]
* 1834 – [[Louis Poinsot]] notes an instance of the [[intermediate axis theorem]]<ref>Poinsot (1834) ''Theorie Nouvelle de la Rotation des Corps'', Bachelier, Paris</ref>
* 1835 – William Hamilton states [[Hamiltonian mechanics|Hamilton's canonical equations of motion]]
* 1838 – Liouville begins work on [[Liouville's theorem (Hamiltonian)|Liouville's theorem]]
* 1841 – [[Julius von Mayer]], an [[amateur]] scientist, writes a paper on the conservation of energy but his lack of academic training leads to a [[Mechanical equivalent of heat|priority dispute]].
* 1847 – [[Hermann von Helmholtz]] formally states the law of [[conservation of energy]]
* first half of the 19th century – [[Cauchy]] develops [[Cauchy momentum equation|his momentum equation]] and [[Cauchy stress tensor|his stress tensor]]
* 1851 – [[Léon Foucault]] shows the Earth's rotation with a huge [[pendulum]] ([[Foucault pendulum]])
* 1870 – [[Rudolf Clausius]] deduces [[virial theorem]]
* 1890 – [[Henri Poincaré]] discovers the sensibility of initial conditions in the [[three-body problem]].<ref>{{Cite journal |last=Poincaré |first=H. |date=January 1900 |title=Introduction |url=https://projecteuclid.org/journals/acta-mathematica/volume-13/issue-1-2/Introduction/10.1007/BF02392506.full |journal=Acta Mathematica |volume=13 |issue=1–2 |pages=5–7 |doi=10.1007/BF02392506 |issn=0001-5962|doi-access=free }}</ref>
* 1898 – [[Jacques Hadamard]] discusses the [[Hadamard billiards]].<ref name=":0">{{Cite journal |last=Oestreicher |first=Christian |date=2007-09-30 |title=A history of chaos theory |url=https://www.tandfonline.com/doi/full/10.31887/DCNS.2007.9.3/coestreicher |journal=Dialogues in Clinical Neuroscience |language=en |volume=9 |issue=3 |pages=279–289 |doi=10.31887/DCNS.2007.9.3/coestreicher |issn=1958-5969 |pmc=3202497 |pmid=17969865}}</ref>