Support and resistance are price levels where a stock has repeatedly stopped falling (support) or stopped rising (resistance) in the past. Support is the "floor" buyers have tended to step in at; resistance is the "ceiling" sellers have tended to appear at.
They are a story about memory and behavior. Example (illustrative): if a stock falls to about $50 three times over a few months and bounces each time, traders start to see $50 as "cheap enough" to buy, so buying clusters there — support at $50. If the same stock keeps stalling near $70, sellers cluster and $70 becomes resistance. The levels are self-reinforcing because so many people watch the same round numbers and prior highs and lows.
When price pushes decisively through resistance, that old ceiling often becomes the new floor — a "breakout", and the flip is called role reversal. The catch: false breakouts are common, where price pokes through a level and then snaps back, trapping traders who chased the move.
Quantustik does not base its forecasts on hand-drawn chart levels — if a level is obvious on every chart, it is already in the price. Our forecasts come from a quantum-mechanics-based model with calibrated confidence bands. Where we reason about price levels, it is through an explicit, testable invalidation level tied to a forecast, not a subjective line. None of this is investment advice.
Support is a level where a stock has repeatedly stopped falling because buyers step in — a floor. Resistance is a level where it has repeatedly stopped rising because sellers appear — a ceiling.
A decisive move above resistance is a breakout, and that old ceiling often becomes new support ("role reversal"). But false breakouts are common, where price pokes through and then snaps back.
They describe where price reacted before, not where it must react next. The levels are subjective and widely watched, so they carry no edge on their own — context for a decision, not a signal.
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Educational research only — not investment advice.