Physics

Physics

Postby Typhoon » Wed Mar 21, 2012 11:20 pm

All the world's a stage.
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Re: Physics

Postby Typhoon » Mon Mar 26, 2012 6:12 am







All the world's a stage.
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Re: Physics

Postby Typhoon » Mon Apr 23, 2012 11:09 pm

All the world's a stage.
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Re: Physics

Postby Parodite » Mon Apr 23, 2012 11:37 pm



Always breath taking... Problem with the factor 10 scaling is you loose track of how f**king big it really is!

I like the growing fingernail one: it keeps it all in our experienced space time map thusly remaining totally imaginable:

* Assume your finger nail grows 3cm/year. (it's actually 1-10cm depending on a number of variables)

* Let it grow for 15 billion years.

* Distance covered: 10x the world round! That's a very long fingernail...

* Then think of the speed of your fingernail growing, representing the speed of light. Then let the light travel for 15 billion years... That is indeed a HUGE universe.

Funny thing here is also.. how relatively sloooooooow the speed of light actually is on the scale of things. As slow as your fingernail is growing 10x around the world...
Outside, away from the noise, grows a flower.
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Re: Physics

Postby HAL9000 » Sun Sep 23, 2012 7:18 am

Parodite wrote:


Always breath taking... Problem with the factor 10 scaling is you loose track of how f**king big it really is!

I like the growing fingernail one: it keeps it all in our experienced space time map thusly remaining totally imaginable:

* Assume your finger nail grows 3cm/year. (it's actually 1-10cm depending on a number of variables)

* Let it grow for 15 billion years.

* Distance covered: 10x the world round! That's a very long fingernail...

* Then think of the speed of your fingernail growing, representing the speed of light. Then let the light travel for 15 billion years... That is indeed a HUGE universe.


Funny thing here is also.. how relatively sloooooooow the speed of light actually is on the scale of things. As slow as your fingernail is growing 10x around the world...



But the slowness of the speed of light is also relative: for an entity moving with a speed approaching the speed of light, time would be very "efficient", in the sense that such a being would feel as if it is everywhere, because of Length Contraction, which means that the relativistic distance for such a being going at speeds close to the speed of light, the distance would actually shrink to zero as the speed approaches the speed of light. The formula is L2= L1*sqrt( 1 - v^2/c^2) where L2 is the transformed length, and L1 is the original length, "sqrt(.)" is the square root operation, v is the speed of the creature, c is the speed of light, and "^" is the notation for the square operation, i.e. x^2 = x* x.

http://en.wikipedia.org/wiki/Lorentz_transformation

http://hyperphysics.phy-astr.gsu.edu/hb ... trans.html

But the trouble is that any creature that has mass, would need infinite energy to reach the speed of light, so this privilege is only for creatures without mass.
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Re: Physics

Postby Typhoon » Sun Jan 26, 2014 8:25 pm

The Feynman Lectures on Physics

The entire three volume opus is now available online for free.

Volume I
mainly mechanics, radiation and heat

Volume II
mainly electromagnetism and matter

Volume III
quantum mechanics
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Re: Physics

Postby Typhoon » Tue Jan 26, 2016 7:28 am

Analogous to thie Feynman undergraduate Lecture Notes on Physics,

much of the Landau - Lifshitz graduate A Course of Theoretical Physics is not available online:

https://archive.org/search.php?query=cr ... ifshitz%22
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