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This Relaxation Oscillator circuit does not simulate in the Time Domain? https://www.circuitlab.com/circuit/9xwwy9/relaxation-oscillator/ My physical circuit works fine.

Oscillators are tricky to simulate, as they all depend on a little bit of random noise, or they need the initial real-world power-up jolt to get them started. You also might try scaling up your resistors by a factor of 10 or 100-- you're asking for an awful lot of current from the output.

Hmm, weird, it seems to simulate like the resistors are always going to the inverting terminal!

See:

It's putting out just what it would if the resistors were hooked up to the inverting input. Something amiss with the simulator?

Think I know what's wrong and the proper way to fix it.

Please see:

Arduinohacker is right though, in some cases (though not, it seems, this one) you might need to use the time operated switch to either insert a voltage step into either one of the supply rails or to set an initial voltage across the capacitor.

A couple of examples of how to kick start an oscillator:

and