quote:

Originally posted by trapper189:
What would happen if the Sun just disappeared? Would the planets immediately just go flying off into space?

quote:

gravity is a force of attraction.

quote:

Originally posted by wrightd:

quote:

Originally posted by Rey HRH:

quote:

Originally posted by Skins2881:

quote:

Originally posted by Rey HRH:


While I agree that mass affects time such as the even horizon of a black hole where time stops, I believe the time rate difference in satellites and planes is caused more by speed rather than mass.

As an object's speed increases, time slows down and as the same object's speed increases, it's mass increases as well.

You've got that wrong. Satellites and planes time dilation is due to gravity. Time dilation due to speed is less noticeable until you get significant fractions of the speed of light. It's almost a flat line until you get to 50% then from 90 to 100% the chart turns near vertical.

Okay, I stand corrected. I'm slow because I'm been mostly laying on my back rather than standing up. I don't mind learning something new. I did fact check you using ChatGPT. I use it for a lot of research. I know it does often come up with factually incorrect answers that are sometimes contradictory with an immediately preceding answer it gives.

quote:

What affects the time rate difference of planes and satellites more compared to time on the surface of the earth - is it the relative speed or the mass of the earth? Give references and citations.

quote:

Both the relative speed and the mass of the Earth have an impact on the time rate difference experienced by planes and satellites compared to time on the surface of the Earth. However, the dominant factor in this context is the gravitational potential, which is directly related to the mass of the Earth.

According to the theory of general relativity, clocks in regions with stronger gravitational fields run slower compared to clocks in regions with weaker gravitational fields. This effect is known as gravitational time dilation. The closer an object is to a massive body, such as the Earth, the stronger the gravitational field and the slower time passes.

The time dilation due to gravitational potential is more significant for planes and satellites compared to the time dilation due to relative speed (special relativity) because the speeds of planes and satellites are relatively low compared to the speed of light. The gravitational time dilation effect dominates in this scenario.

References:

Rindler, W. (2006). Relativity: Special, General, and Cosmological. Oxford University Press. ISBN: 978-0198567325.

Hartle, J. B. (2003). Gravity: An Introduction to Einstein's General Relativity. Pearson Education. ISBN: 978-0805386622.

Misner, C. W., Thorne, K. S., & Wheeler, J. A. (2017). Gravitation. Princeton University Press. ISBN: 978-0691177793.

These references provide detailed explanations of the concepts of special relativity and general relativity, including the effects of relative speed and gravitational potential on time dilation. They support the understanding that the dominant factor affecting the time rate difference of planes and satellites compared to time on the surface of the Earth is the gravitational potential, which is determined by the mass of the Earth.

There is a cool youtube video of a professor taking his students to a high elevation with one atomic clock after syncing a second clock at their starting point. When they returned the clock they took with them after driving to the top of a mountain had a different time. That was amazing. Another video is one I think they did in the 70s, syncing two clocks, then flying one of them around the world on a passenger jet, then showing the difference when they returned. Again pretty powerful demonstration of the physics. In both cases, however, no matter how dramtic the difference, you would never be able to notice it yourself, since in both cases this affect is only noticeable from a relatavistic point of view between two different inertial frames of reference (I hope I got that right). Within your own intertial frame of reference (whether going slow or fast etc) everthying is normal to you no matter your speed or gravitational well. It's at the extremes however that I don't understand - the gravity of a black hole, or the speed of light - and that I THINK is where Einsteins equations on this stuff break down. So maybe that's the answer - which is we still don't really know.

quote:

Originally posted by bobtheelf:

quote:

Originally posted by trapper189:
What would happen if the Sun just disappeared? Would the planets immediately just go flying off into space?

Not immediately. The effects of gravity travel at the speed of light, so it would take about 8 minutes before we noticed we were no longer orbiting. When the big light went out.

quote:

Originally posted by bcereuss:

quote:

Originally posted by bobtheelf:

quote:

Originally posted by trapper189:
What would happen if the Sun just disappeared? Would the planets immediately just go flying off into space?

Not immediately. The effects of gravity travel at the speed of light, so it would take about 8 minutes before we noticed we were no longer orbiting. When the big light went out.

I think you’re talking about gravitational waves, not actual gravity.

quote:

Originally posted by bcereuss:

quote:

Originally posted by bobtheelf:

quote:

Originally posted by trapper189:
What would happen if the Sun just disappeared? Would the planets immediately just go flying off into space?

Not immediately. The effects of gravity travel at the speed of light, so it would take about 8 minutes before we noticed we were no longer orbiting. When the big light went out.

I think you’re talking about gravitational waves, not actual gravity.