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The fastest pulsar spins at 716Hz; its equator spins at 24% the speed of light

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Re: The fastest pulsar spins at 716Hz; its equator spins at 24% the speed of light

#4
post #3

does this mean that time flows significantly faster on the outside of the pulsar then on the inside, if so does this significantly impact the pulsar dynamics?

It doesn't affect the dynamics, but it might affect the radiation emitted by it as seen from the outside. All particles in the dilated reference experience the same dilation (approximately - it does vary radially, not sure if significant).

Re: The fastest pulsar spins at 716Hz; its equator spins at 24% the speed of light

#5
post #3

does this mean that time flows significantly faster on the outside of the pulsar then on the inside, if so does this significantly impact the pulsar dynamics?

There is not much difference. The relativistic factor is 1.030107, that is a ~3% change.

EDIT:

My amateur physics say that the gravitational well adds 9.7% to that.

I tried the same calculation for earth and it gave a sensible result: a change of 6.95 * 10^-10.

Here is an answer from physics exchange which gets the same result: http://physics.stackexchange.com/questions/10089/gravitation...

Re: The fastest pulsar spins at 716Hz; its equator spins at 24% the speed of light

#6
post #5
post #3

does this mean that time flows significantly faster on the outside of the pulsar then on the inside, if so does this significantly impact the pulsar dynamics?

There is not much difference. The relativistic factor is 1.030107, that is a ~3% change. EDIT: My amateur physics say that the gravitational well adds 9.7% to that. I tried the same calculation for earth and it gave a sensible result: a change of 6.95 * 10^-10. Here is an answer from physics exchange which gets the same result: http://physics.stackexchange.com/questions/10089/gravitation...

That's about 11 days per year, or 43 minutes per day.

Re: The fastest pulsar spins at 716Hz; its equator spins at 24% the speed of light

#8
post #5
post #3

does this mean that time flows significantly faster on the outside of the pulsar then on the inside, if so does this significantly impact the pulsar dynamics?

There is not much difference. The relativistic factor is 1.030107, that is a ~3% change. EDIT: My amateur physics say that the gravitational well adds 9.7% to that. I tried the same calculation for earth and it gave a sensible result: a change of 6.95 * 10^-10. Here is an answer from physics exchange which gets the same result: http://physics.stackexchange.com/questions/10089/gravitation...

Keep in mind that differences in gravity will also affect time dilation.

Re: The fastest pulsar spins at 716Hz; its equator spins at 24% the speed of light

#10
post #7

Anyone feel like calculating the energy embodied in just the rotation of this star?

About 10^46 J?

In the classical approximation (1/2 Iω^2), assuming a uniform sphere of 2.0 solar masses and r=16 km.

That's about 3% of the mass-energy (mc^2 = 3e47 J).

This could be way off.

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