What would the world be like if c→∞ and h=0?

[GW150914]

What would the world be like if the speed of light is infinity and the Planck constant is zero (therefore the world is totally Newtonian)?

 

[Vanadium 50]

As you say, totally Newtonian.

 

[Nugatory]

In that world, several things would happen that don't happen in the real world that we live in:
- All atoms would be unstable, so there would be no matter as we know it.
- Even if there was some way of getting around that unstable atom problem, objects would radiate unlimited amounts of energy and would never come into thermal equilibrium with their surroundings.
...
And so on, through a long litany of problems.

The physicists of the early twentieth century didn't invent relativity and quantum mechanics because they were sadistic and wished to inflict pain on future generations of physics students. They invented relativity and quantum mechanics because (although it works really well in many areas) classical Newtonian mechanics doesn't completely explain the universe we live in.

 

[atyy]

In that world, several things would happen that don't happen in the real world that we live in:
- All atoms would be unstable, so there would be no matter as we know it.
- Even if there was some way of getting around that unstable atom problem, objects would radiate unlimited amounts of energy and would never come into thermal equilibrium with their surroundings.
...
And so on, through a long litany of problems.

Perhaps for these problems we only need h=0. I think for QED one can safely take c to infinity, since lattice QED with small enough spacing should be compatible with all QED experiments. I think the chiral fermion problem is one issue about which we don't yet know whether it is safe to take c to infinitity.