I really need someone to tell me I'm wrong and why here or this is going to keep bothering me. As far as I'm aware, a thermocouple works by heating the same side of two different materials, one p-type and one n-type. Since charge carriers also serve to conduct thermal energy, the charge carriers on the hot side will have a net migration over to the cold side building up a positive charge on the cold side of the p type material and a negative charge on the cold side of the negative terminal: this is a difference in potential (voltage). Generally, thermocouples connect the two materials together at the hot side and connect the cold sides of the materials together through a load, completing a circuit and generating current flow. That all said, what happens if you do not connect the p and n type materials together on the hot side? Obviously current will not flow, but you should still be generating a difference in potential on the cold sides, right? Couldn't you still figure out the temperature from the voltage generated even without completing the circuit then? Again, please tell me I'm wrong and why.