Plum pudding model
Channel: all the knowledge of the universe PRINCIPIA
Date: 2021-12-04

Plum pudding model, by Wikipedia https://en.wikipedia.org/wiki?curid=2840 / CC BY SA 3.0

#Foundational_quantum_physics
The plum pudding model of the atom The current model of the sub-atomic structure involves a dense nucleus surrounded by a probabilistic "cloud" of electrons The plum pudding model is one of several historical scientific models of the atom.
First proposed by J. J. Thomson in 1904 soon after the discovery of the electron, but before the discovery of the atomic nucleus, the model tried
to explain two properties of atoms then known: that electrons are negatively charged particles and that atoms have no net electric charge.
The plum pudding model has electrons surrounded by a volume of positive charge, like negatively charged "plums" embedded in a positively charged "pudding".
It had been known for many years that atoms contain negatively charged subatomic particles.
Thomson called them "corpuscles" （particles）, but they were more commonly called "electrons", the name which G. J. Stoney had coined for the "fundamental unit quantity of electricity" in 1891.
It had also been known for many years that atoms have no net electric charge.
Thomson held that atoms must also contain some positive charge that cancels out the negative charge of its electrons.
Thomson published his proposed model in the March 1904 edition of the Philosophical Magazine, the leading British science journal of the day.
In Thomson's view: ... the atoms of the elements consist of a number of negatively electrified corpuscles enclosed in a sphere of uniform positive electrification,
... J.J. Thomson had followed the work of Thomson Lord Kelvin who had written a paper proposing a vortex atom in 1867.
J.J. Thomson abandoned his 1890 "nebular atom" hypothesis, which was based on the vortex theory of the atom, in which atoms were composed of immaterial
vortices and suggested that there were similarities between the arrangement of vortices and periodic regularity found among the chemical elem...