Market heavyweights Apple Inc AAPL.O, Alphabet Inc GOOGL.O, Microsoft Corp MSFT.O and Amazon.com Inc AMZN.O fell between 2.4% and 5.9%. By Anisha Sircar and Sruthi Shankar June 13 (Reuters) - Wall Street's main stock indexes fell sharply and the S&P 500 was on track to confirm a bear market on Monday on fears that the Federal Reserve's aggressive interest rate hikes would tip the economy into recession. All the major S&P sectors were sharply lower, with energy .SPNY and consumer discretionary .SPLRCD leading the declines, as worries over inflation, rate hikes and the Ukraine war unnerved investors.