the difference between vision and the tactual sensation in the VR world.
the possibility of the connections between sensor with body: the distance between the user and the object
sensor: Sonic ultra sound distance sensor
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question: how to different the object in the real world and the one in the VR world for the user?
topic: Surveillance of the digital data
the possibility of the connections between the sensor and body: arm muscles detection, breath, microphone
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question: can the user really detect that the movement of the object in the virtual reality world are caused by them?