It's calculated using Momentum, Acceleration and Probability (Psychological Effect) by interfering the Golden Ratio!
I got the idea thanks to Tradingview user DGT (dgtrd) and his/her excellent descriptions.
The indicator is simplified for users and the default settings work great, so use it as you like specially as a trend indicator.
In true TradingView spirit, the author of this script has published it open-source, so traders can understand and verify it. Cheers to the author! You may use it for free, but reuse of this code in a publication is governed by House Rules. You can favorite it to use it on a chart.