# Question about relationship between quantum/relativistic physics

1. Jun 12, 2010

### CptPlanet

First post. Hope I'm doing it right.

So, I was puzzling through some of the very basic ideas of quantum physics and special relativity and I came up with an unusual place where they might agree.

Special relativity states that every frame of reference is as valid as every other one. That is, there is no "universal frame of reference" by which events in space and time can be measured.

If there were a universe where it was possible to have a universal frame of reference, what would it look like? You would need every particle moving in exactly the same direction at exactly the same speed. If you were an observer in that universe, nothing would be moving in relation to you at all. It would be identical to a universe where every particle had been cooled to absolute zero.

Quantum physics tells us that it is impossible to know both the position and momentum of a particle to exact precision, which would be the norm in the hypothetical universe I just described, therefore there cannot be a "special case" universe that allows for a universal frame of reference according to the physical laws as we understand them.

Has there been any discussion on that idea, or other ideas where quantum physics and relativity corroborate each other in strange ways? Additionally, if I'm missing something fundamental about either theory, please feel free to disabuse me of my ignorance!

2. Jun 15, 2010

### mt8891

quantum field theory has something to do with quantum mechanics and special relativity.

3. Jun 15, 2010

### HallsofIvy

I don't see how that follows. Our "every day" universe, as we observe things moving relative to us with non-relativistic speeds, relative to the ground, is precisely a world in which there is a "universal frame of reference".

4. Jun 15, 2010

### mt8891

I think the idea is that if things were 'frozen' and there was nothing moving around..what would a reference frame be like in that situation.

the problem I sense is that of "the universe" becoming increasingly unstable as it cooled since there would still be the conservation of all the mass and energy. "the universe" might eventually stop "running" (like a machine) but it still has to be there in some form perhaps as potential energy. to me it seems analogous to capacitance or even differences in potential.