21. Heat causes electrons to move around and distort the current in the fMRI detector, producing thermal noise . 22. For example, at 1 MHz the man-made noise might be 55 dB above the thermal noise floor. 23. Many researchers are presently engaged in understanding how molecular-scale motors operate in environments with non-negligible thermal noise . 24. Theoretical analysis indicates that even this impressive feat is far from pushing the limits set by thermal noise . 25. This TES array is cooled to a temperature of 0.3 Kelvin to reduce thermal noise in the detectors. 26. Some devices are only practical to operate cryogenically as otherwise the thermal noise would swamp the detected signal. 27. Thermal noise rises with the temperature.28. Thermal noise is a different physical effect that superimposes on the shot noise, contributing to the experimentally-measured value.29. Thermal noise is approximately white, meaning that its power spectral density is nearly equal throughout the frequency spectrum.30. Thermal noise can be made lower by cooling the circuits, but this is only usually worthwhile on radio telescopes.
