Alphabet, the parent company of Google, experienced a sharp decline in its share price, falling 13.4% during a single trading session on Wall Street. This sell-off, which threatens to erase nearly $500 billion from its market valuation, stems from investor apprehension regarding heavy spending on artificial intelligence and decelerating revenue growth. Although third-quarter revenue reached $127.6 billion—marking a 25% increase—it fell short of analyst expectations of $128.2 billion. Furthermore, the growth rate of Google's search engine slowed to 12%, down from 17% in the previous quarter, raising significant concerns about the return on investment for the firm's primary advertising business.