Here are some "on"s in Physics.
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Fundamental "on"s: Let me say very crudely that the fundamental "on"s can be classified as bosons and fermions.
Bosons are basically particles which obey Bose - Einstein statistics (i.e. particles with zero or integral spin) .
Fermions are particles which obey Fermi - Dirac statistics (i.e. particles with half integral spin).
It so happens that in nature, at a very fundamental level, bosons act as carriers of force between the fermions. The bosons which carry the four basic forces of nature are all "on"s, photon for electromagnetic force, massive vector bosons (W+- and Z0) for weak force, gluons for strong force and gravitons for gravitational force.
The fundamental particles in the theory called standard model also are "on"s, hadrons (crudely) and leptons. Well hadrons are not actually that much fundamental, they are of two types, baryons and mesons. Well it happens that mesons are bosons and hadrons are fermions :) , because baryons contain three quarks ( the most fundamental class of particles like leptons) and mesons contain two quarks. An example of a meson is the famous pion. Now proton and neutron , the nucleons at least most people know, are baryons. (But most other baryons are not "on"s.)
Now coming to the leptons, all charged ones are "on"s, electron, muon and tauon (but precisely tau particle), but the uncharged ones are all "ino"s. :) That is for another occasion.The anti particle of electron is an "on" with a unique name positron.
So much for the fundamental level. Now let us see some non fundamental "on"s.
Bohr magneton : physical constant corresponding to the magnetic moment of electrons; the magnitude of the magnetic dipole moment of an orbiting electron in the ground state.
Phonon : quantum of lattice vibration.
Soliton : self-reinforcing solitary wave (a wave packet or pulse) which keeps its shape while travelling at a constant speed. A cancellation of nonlinear and dispersive effects gives rise to solitons in a medium.
Exciton : a bound state of an electron and a hole (the absence of an electron) in insulators,semiconductors and some liquids.
Plasmon :quantum of plasma oscillation. Plasmons are collective oscillations of the free electron gas density, say, at optical frequencies.
Polariton : results from the strong coupling of electromagnetic waves with an electric or magnetic diploe carrying excitation.
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These are some of the "on"s I find in Physics. If you find more "on"s, please don't forget to comment. :)
Reference : Wikipedia
Tuesday, July 20, 2010
Friday, June 12, 2009
NANO TECHNOLOGY
This article will be published in series. Otherwise it will be very boring for you readers to read it.
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"Nano" is something which we hear very often these days; no matter it is used academically or not. The word "nano" would always remind the physicsts of the fields of nanosciecne and nanotechnology. Now what is nanotechnology? Lets have a look at it.
"Nano" means of the order of 10^(-9).
1nm= 10^(-9)m
Thus nano technology is the technology of particles having sizes in the nanometer regime. Nanotechnology is a wonderful innovation of the 20th century, but it is hailed as the 21st century technology. It was Sir Richard Feynman who laid the foundation to the wild idea of nanotechnology. His article "There's plenty of room at the bottom" describes how all the volumes of encyclopedia Britannica can be stored at he tip of a pin!
Though nanotechnology has been in use for centuries now, not many people are aware of it. Eg) Gold nanoparticles were used to colour cups and such things in ancient periods.
Nanotechnology is basically a branch of material science. In the nano regime, many material properties are different from those of the bulk material.
For example, we all know that aluminium is a good conductor of electricity. It conducts electricity with the help of free electrons present in it.This is bulk's property. When aluminium is cut into small pieces of nanometer size, it becomes a dielectric (ie a substance which transmits electric effects without conducting). Thus, size reduction changes the material's properties.
Some early findings in the direction of nanoscience are the following:
(1) Existence of nano ohase as primordial materials condensed from solar nebule and meteeorites.
(2) Occurance of mineral species as small crystallite.
(3) In 1861 Ostwald laid the foundation of colloidal science. he said that colloidal particles neglected dimensions.Around 1900, Einstein and John Tyndall characterised colloids.
(4) In 1962, Kubo discovered that physical properties of small metal particles will be quite different from those of bulk materials.
All these led to investigations on nanoparticles.
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Thats all for today. :)
*************************************************************************************
"Nano" is something which we hear very often these days; no matter it is used academically or not. The word "nano" would always remind the physicsts of the fields of nanosciecne and nanotechnology. Now what is nanotechnology? Lets have a look at it.
"Nano" means of the order of 10^(-9).
1nm= 10^(-9)m
Thus nano technology is the technology of particles having sizes in the nanometer regime. Nanotechnology is a wonderful innovation of the 20th century, but it is hailed as the 21st century technology. It was Sir Richard Feynman who laid the foundation to the wild idea of nanotechnology. His article "There's plenty of room at the bottom" describes how all the volumes of encyclopedia Britannica can be stored at he tip of a pin!
Though nanotechnology has been in use for centuries now, not many people are aware of it. Eg) Gold nanoparticles were used to colour cups and such things in ancient periods.
Nanotechnology is basically a branch of material science. In the nano regime, many material properties are different from those of the bulk material.
For example, we all know that aluminium is a good conductor of electricity. It conducts electricity with the help of free electrons present in it.This is bulk's property. When aluminium is cut into small pieces of nanometer size, it becomes a dielectric (ie a substance which transmits electric effects without conducting). Thus, size reduction changes the material's properties.
Some early findings in the direction of nanoscience are the following:
(1) Existence of nano ohase as primordial materials condensed from solar nebule and meteeorites.
(2) Occurance of mineral species as small crystallite.
(3) In 1861 Ostwald laid the foundation of colloidal science. he said that colloidal particles neglected dimensions.Around 1900, Einstein and John Tyndall characterised colloids.
(4) In 1962, Kubo discovered that physical properties of small metal particles will be quite different from those of bulk materials.
All these led to investigations on nanoparticles.
***************************************************************************************
Thats all for today. :)
Monday, June 1, 2009
About Scientist-PHY
Hi friends,
The fever of blogging has been on me for the past two weeks. I already have two blogs, one in English and the other in Malayalam, and they are soley dedicated to heart! So I thought why not start a blog solely dedicated to brain? Here it is. This is intended to be a Physics blog, but other topics may also find their way into the pages, here. :) I wish to write in my own words, things known to me and share the knowledge I've with everyone who reads this. The things which I write won't be my findings or so, I will just act like an allocator of knowledge. If there are any mistakes, readers are welcome to correct them. So here I come. :)
The fever of blogging has been on me for the past two weeks. I already have two blogs, one in English and the other in Malayalam, and they are soley dedicated to heart! So I thought why not start a blog solely dedicated to brain? Here it is. This is intended to be a Physics blog, but other topics may also find their way into the pages, here. :) I wish to write in my own words, things known to me and share the knowledge I've with everyone who reads this. The things which I write won't be my findings or so, I will just act like an allocator of knowledge. If there are any mistakes, readers are welcome to correct them. So here I come. :)
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