# J.C.MacSwell

Senior Members

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2. ## X-ray

How about 10% from "other than the sun"? Or is that still way too high?

4. ## 0 Velocity?

Yes, up to but not including, 2c. (locally) (first question is no anyway due to Hubble but yes locally in either objects rest frame)

6. ## How to cancel out earth gravity.

The simplest way to beat gravity is the "bootstrap" method. You need good balance and very strong arms and laces (regular shoe laces will probably break). You lean over so that your center of gravity is directly over your laces and pull straight up. If you pull hard enough (the force must exceed your weight plus the tension on your laces) you will rise and "hover" for a few seconds before falling over. Good balance is the key. Once you leave the ground it is like balancing a pencil on it's point so a couple of seconds is extremely good.
7. ## Is the Universe travelling or the Space Ship ?

You are doing quite a job explaining Euclidean space. If you try real hard you can explain Euclidean space in a number of ways. You can come up with many more examples of Euclidean space. But it will still be Euclidean space. It will be a very good model of reality at low speeds and a very poor one when higher speeds are involved.
8. ## Is the Universe travelling or the Space Ship ?

I think that if it was obvious we would already know what it was.

10. ## Is the Universe travelling or the Space Ship ?

...and expand and/or contract, constantly or at a varying rate, with respect to another frame.
11. ## Is the Universe travelling or the Space Ship ?

You will be telling us at your Nobel prize acceptance speech! (I do not know but I'm sure it's not Euclidean)
12. ## Is the Universe travelling or the Space Ship ?

Johnny, this is how these frames work by definition. If you somehow come up with absolute frames that work differently that would be great. I won't say it is impossible. But, the way these frames are defined, that is the way they work.

14. ## Gravity and velocity

When it is not an inertial frame the forces do not have to net to zero to have the particle/body remain stationary in that frame. It often requires a pseudo force (coriollis etc.) to accomplish this.
15. ## Gravity and velocity

This is a very commonly used frame, perhaps the most common. Be careful not to use this frame in extremes however. The speed of light is not constant in this frame.
16. ## Alternate dimensional existance

I think they meant if they were only 2D they would disappear to the others in 2D. Similarly if you are only 3D you would disappear into a fourth dimension.
17. ## Is the Universe travelling or the Space Ship ?

Keep in mind the Universe cannot be defined as a frame in this sense. It includes all frames.
18. ## Mars

It's a Bi-ped for sure, as the sea turtle entering the bottom of the picture can clearly see! Obviously some humanoid arrived first, followed by even more intelligent sea creatures that do not require spacesuits in that atmosphere. As for the colour of the surface, I don't think we should jump to any conclusions without some more data.
19. ## The Sun and its Gravity

Has temperature/emits photons.
20. ## Relativistic length contraction question

I think you are right if your assumptions are right. However, I think you are not right, except when your "loop" is at rest (not spinning).

23. ## Electrical Wind

Blades/runners work much better but make sure the water is solid.
24. ## Question about General Relativity Theory

"Isentropic Red"
25. ## Questions about Special Relativity

Yep, Lorentz and Galileo. Clearly there ain't enough room in this town for the two of them. Now, a kinder, gentler town (read lower the relative speeds of them yardsticks). I can see maybe they might get along a little better there. (not perfectly though)
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