Sandor Ferenczi, a Hungarian psychoanalyst who was a contemporary and colleague of Sigmund Freud, did not appear to be directly influenced by the development of quantum physics in the 1920s. While there were some parallels between the emerging concepts of quantum physics and Ferenczi's ideas about the unconscious mind, these similarities were likely coincidental rather than the result of a direct influence.
Ferenczi was primarily interested in exploring the interpersonal dynamics between therapist and patient and developing techniques for working with trauma and other forms of psychological distress. He was known for his innovative approach to psychoanalysis, which included techniques such as active listening, empathic attunement, and mutual analysis.
While Ferenczi did not explicitly reference quantum physics in his work, some of his ideas about the unconscious mind do bear a resemblance to concepts from quantum mechanics, such as the idea that the observer can influence the observed phenomenon. For example, Ferenczi's concept of "suggestion" suggests that the therapist's attitude and behavior can influence the patient's psychological state and promote healing.
In conclusion, while there may be some overlap between Ferenczi's ideas and the emerging concepts of quantum physics in the 1920s, there is no direct evidence that Ferenczi was influenced by quantum physics in his work as a psychoanalyst.
