Where does deflection collide?

The distance a loaded beam moves from its unloaded position, and the curved shape its axis takes under that load. Jacob Bernoulli's 1694 study of the elastica, the curve of a bent elastic strip, first framed this bending mathematically, and Euler's 1744 Methodus inveniendi lineas curvas gave the first correct relation between the load, the beam's stiffness, and the deflection of its end. The referent is a physical displacement of a solid member measured in units of length, and it is not a particle bent off course by a field, a person diverting emotional contact, or a computed gap between social feelings.[1][2][3]

Unit

One beam's displacement under load, in units of length such as millimetres or inches

Recovery means

An elastic beam springs back to its original position once the load is removed, provided the material stays within its elastic range

Measured by

Computed from load, span, and the beam's flexural stiffness, and checked directly with dial gauges, deflectometers, or laser sensors

The change in a moving particle's path when a force field pushes it aside from a straight line. J. J. Thomson's 1897 Cathode Rays measured how a beam of the particles now called electrons bent under electric and magnetic fields, and used the size of that bending to find the ratio of their charge to their mass. The referent is the curving of a trajectory through space, set by the field strength and the particle's charge, speed, and mass, and it is unrelated to a sagging beam, a person avoiding contact, or a mismatch of social sentiments.[4]

Unit

One particle's angular change of direction, measured as an angle from its original path

Recovery means

Not applicable

Measured by

Read from the displacement of the beam on a detecting screen, or from the curvature of a track in a field of known strength

A way of turning aside from direct emotional contact so that its intensity is softened before it lands. Polster and Polster's 1973 Gestalt Therapy Integrated named this within the contact-boundary framework of Gestalt therapy, describing it as taking the heat out of contact through humour, vagueness, changing the subject, or looking away. The referent is a person's habitual diverting of experience away from full contact, observed in the consulting room, and it has nothing to do with a bent beam, a particle steered by a field, or a numeric gap in social meaning.[5]

Unit

One instance of a person diverting contact away from full emotional engagement

Recovery means

Not applicable

Measured by

Identified clinically from behaviour and language, such as deflecting eye contact, joking, or shifting topics, rather than by a numeric scale

The distance between the stable feeling a person holds about an identity or act and the momentary impression an event creates about it. David Heise's 1977 Social action as the control of affect defined this gap and proposed that people act to reduce it, and his 1979 book Understanding Events built it into affect control theory as a quantity computed across dimensions of evaluation, potency, and activity. The referent is a calculated mismatch between lasting and situational sentiments, expressed as a number, and it is distinct from a beam's sag, a particle's bent path, or a Gestalt client's avoidance of contact.[6][7]

Unit

One event's summed squared difference between fundamental and transient sentiments across three affective dimensions

Recovery means

Not applicable

Measured by

Calculated from evaluation, potency, and activity ratings of the identities and behaviours in an event, using affect control theory equations