Sensors have long been available to give quick readings of physical variables, like pressure and temperature.

Furthermore, a mind-independent property does not have to be the value of some physical variable such as position or momentum.

For him, painting is a set of physical variables and he has spent a career playing with them.

This may be some physical variable such as temperature or chemical concentration.

The sensors would measure several physical variables of interest which typically include:

And that's all it can have-no other physical variables are permitted.

Measurements made include a wide range of physical, chemical and biological variables.

The idea is to pick one of the physical variables to be a clock and asks relational questions.

In fact, it can be very complicated, depending upon the physical and chemical variables involved.

It turned out that all nine of the physical variables did contribute to the outcome (see the table above).