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Physics, Astronomy & Cosmology / What are the relativistic effects of super high temperature on mass?

« on: 14/10/2013 17:30:19 »

How will temperature effect mass in a relativistic way?
for example how would the relativistic mass of a system of particles - A, with n number of particles and temperature T where all particles have rest mass m differ to an identical system of particles - B, but with temperature T+x ?

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Physics, Astronomy & Cosmology / Re: What experimental effects does altitude have on balloons

« on: 13/10/2013 14:48:38 »

units for pressure 1 Pa= 1Nm^-2 units for volume m^3
so units for pressurevolume would be Nm
That's interesting

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Physics, Astronomy & Cosmology / Re: What experimental effects does altitude have on balloons

« on: 12/10/2013 17:49:29 »

Assuming both balloons were both inflated to the same volume:

The first balloon inflated at sea level would expand at the top of mt Everest because the air pressure is higher at sea level than it is at high altitude, the air is not pushing on the outside of the balloon as much as it was at sea level while the pressure inside the balloon remains constant, and so the volume increases.

The second balloon inflated at altitude and brought to sea level would decrease in volume due to increasing air pressure i.e having the opposite effect that the first balloon experienced.
 

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Physics, Astronomy & Cosmology / Can you diffract other EM waves the same way white light is?

« on: 12/10/2013 17:36:04 »

You can diffract white light into the visual spectrum of different colours, so can you diffract other parts of the EM spectrum in the same way?
e.g can you diffract 'white' radio waves into different 'colours'?
Where 'white' would mean un-polarised, non-coherent and a mixture of wavelengths .

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Physics, Astronomy & Cosmology / Re: Does gravity alter the speed of light?

« on: 09/10/2013 20:51:18 »

When we illustrate the path of light in warped space-time by drawing it on a flat 2D surface, the result is a curved path. If we draw the space-time grid on that same 2D surface, it should appear warped, and the light's path should be parallel to the warped coordinates. In Minkowski 4D coordinates, the path of light is a straight line. In fact, the 4D space-time grid is defined by the straight paths of imaginary photons. So, in Minkowski space-time, light does not accelerate in either speed or direction.
 
This doesn't mean that Euclidean space is invalid. It just isn't as useful as Minkowski space-time for calculating trajectories in gravitational fields. In Euclidean space, a photon does accelerate. It's momentum changes when passing near a star, which means the star is pulling the photon with a gravitational force. Conservation of momentum dictates the photon must exert an equal and opposite gravitational force on star. Thus, in Euclidean space, a photon has a gravitational field of its own.
 
Unfortunately, the use of Euclidean space necessitates a whole different set of definitions for units of space, time, etc. The math is unwieldy, even more so than the math of general relativity.
 
If I had any aptitude for math, I think I would use numerical analysis to predict paths in Euclidean space, and I'd expect to get results equivalent to those derived by Einstein's general relativity. The results should be equivalent in predicting whether two objects will collide or orbit. The two methods should agree on what a space traveler would observe on his clock and what he should see out his window.

very informative post thank you, euclidean spacetime is very wacky and intriguing.
So now im wondering in euclidean spacetime photons have mass correct? so can you accelerate any other massive particle to the speed of light?

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Physics, Astronomy & Cosmology / Does gravity alter the speed of light?

« on: 08/10/2013 23:15:37 »

Light is affected by gravity, its path is bent by gravity, demonstrated by gravitational lensing.

This got me thinking: speed of light is a constant, as we all know, however if its path and therefore direction is changing, is its velocity too? is light under acceleration when passing through a gravitational field?