# How is the speed of light an absolute maximum speed in the universe? [closed]

Under the heading which came first, the chicken or the egg, which came first: the maximum velocity of electrons orbiting the atom, or the speed of light as the maximum velocity limit? Is it possible that when an object reaches the velocity at which its forward velocity equals its electron(s) orbital speed around its nucleus, then its advancing electrons would cease to spin around their orbit, lose their centrifugal force, and collapse into its nucleus, and the retreating electrons would lose their forward speed and the atom would run away from them, and shed them as radiation? Could this limit the maximum velocity at which a mass can travel, and this define the speed of light? If this is true, then at the speed of light its mass would not become infinite, in according to Einstein, but the mass would transmute into pure energy, in other words, become light or some other radiation frequency.

• – John Rennie Oct 22 '13 at 17:14
• I probably don't know enough to satisfactorily answer your question, but can you clarify: "...and the retreating electrons would lose their forward speed and the atom would run away from them, and shed them as radiation?" – shortstheory Oct 22 '13 at 17:16
• @shortstheory do you say that you imagine the object reaches the velocity at which its forward velocity equals its electron(s) orbital speed around its nucleus? – Val Oct 22 '13 at 17:38
• Under the heading “ which came first, the chicken or the egg,” or the gibberish which follows? I'm surprised this question hasn't been closed yet. Seriously, what on earth is "its forward velocity equals its electron(s) orbital speed around its nucleus" supposed to mean? – Alfred Centauri Oct 22 '13 at 20:00
• "the velocity at which its forward velocity equals its electron(s) orbital speed around its nucleus" is comparing angular velocity with linear velocity. Apples and oranges really... Also, electrons do not revolve around the nucleus as per our current model of the atom – Pranav Hosangadi Oct 23 '13 at 4:02

There is a fundamental symmetry of the universe called Lorentz invariance, and the speed of light is a constant involved in this symmetry. See the question What is so special about speed of light in vacuum? for more discussion of this. So the speed of light is far more than some side effect of the way electrons behave. Indeed we require all physical theories to be (locally) Lorentz invarient.

In any case, your example of the atom is not a good one because the electrons do not orbit the nucleus in the way you describe. The electrons in atoms are delocalised and do not have a well defined position like a planet orbiting a star. Indeed the electrons in an atom need not have any angular momentum at all. The electron in the ground state of a hydrogen atom has an average angular momentum that is zero, so it cannot be said to be orbiting anything.

• Forgive me if I'm wrong, but isn't $l= \hbar$ for the ground state? – Javier Oct 22 '13 at 17:50
• No. The orbital angular momentum is $\sqrt{\ell(\ell+1)}$, and for the ground state $\ell = 0$. – John Rennie Oct 22 '13 at 17:54
• Oh, you're right, sorry. – Javier Oct 22 '13 at 21:27

Is it possible that when an object reaches the velocity at which its forward velocity equals its electron(s) orbital speed around its nucleus, then its advancing electrons would cease to spin around their orbit, lose their centrifugal force, and collapse into its nucleus, and the retreating electrons would lose their forward speed and the atom would run away from them, and shed them as radiation?