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Does time warp inside the sun?

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50 utenti della rete avevano questa curiosità: Spiegami: Does time warp inside the sun?

So while reading some science texts on the sun, I came across this:

What is particularly interesting about the radiative zone, is that it can take millions of years for a photon to pass through this zone to get to the next zone

So I already understand this much:

  • Light is made of photons, which are a particle and a wave.

  • The speed of light is a universal constant. (E=mc²)

  • Gravity can warp spacetime.

  • Since time is relative, when moving at relativistic speeds, time can “slow” for the fast moving object.

So if light particles are slowed inside the sun, does that mean that time is slowed as well?

Ed ecco le risposte:

Time does run slower close to, or inside, a massive object like a star. But for the Sun that’s a very minor effect.

The other comments explain why it takes energy a long time to reach the surface.

No, it’s due to the fact that the particles are so densely packed the photons can continue to bounce from particle to particle before they reach the surface and can escape. This combined with the fact that the distance from the core (where the fusion happens and the photons are released) to the outside is just under 700,000km of maze for the photons to travel through.

The speed of light is not constant when moving through something. Actually, light is repeatedly absorbed and re-emitted as it hits things while it passes “through” a substance, even if that appears clear like air or glass.

The much denser and not “clear” substance in the sun slows light even more than glass or air.

The constant c is defined as the speed of light in a vacuum. When light passes through a medium it is slowed down. The refractive index of a material is the ratio of the nominal speed of light, c, divided by the speed of light in the material. Most natural materials on earth have index values of 1 to 3.

Stars are so physically dense that their indeed value is in the millions and hense the speed of light is very very slow inside stars.

A picture I am not yet seeing in this thread:

Because matter inside a star is so dense, light cannot travel far without ramming into another atom.

So that photon is absorbed by that atom, which goes into an “excited” state with the additional energy. It cannot stay long in such a state, and in dropping back down to a non-excited state, re-emits a photon. However, this re-emission can be in any direction.

Including heading deeper into the sun.

So any “single photon” can and does bounce around for many millions of years in what is called a “random walk” before statistical chance brings it close enough to the surface of the sun to start travelling decent distances outwards before being absorbed by another atom, thereby increasing its outward travel.