c.2013 New York Times News Service

c.2013 New York Times News Service

SAN FRANCISCO — Max Ganik has no doubts that Twitter’s stock — up 145 percent since it first began trading Nov. 7 — is firmly in bubble territory.

“But that doesn’t mean it’s going to stop going up,” said Ganik, 16, a junior at a high school in Scarsdale, N.Y., who doubled his money by lunchtime on Thursday trading Twitter stock options, and planned to dive back in Monday. “Traders are going to drive up the price. The valuation doesn’t actually matter at this point.”

Ganik is certainly on the young side for a Twitter trader — and as a minor, he needs his mother, Dahlia, to handle the actual trades. But his sentiments help explain the mixture of hope and cynicism that has pushed up Twitter’s stock by 76 percent from Dec. 1 through Thursday, then sent the shares plunging 13 percent Friday to $63.75 — all without any changes in the company’s prospects.

Although tech stocks may not have quite returned to the anything-goes era of Pets.com and TheGlobe.com, the rapid rise in Twitter’s stock is a sign of the overall giddiness infecting Silicon Valley.

Internet stocks have run up sharply this year, exceeding the broad stock market’s strong rally. Venture capitalists and angel investors are flush with cash and complain that they are having trouble finding smart places to put it. Startups like the instant-messaging firm Snapchat, which turned down a buyout offer of nearly $3 billion in November, are remaining independent with hopes of becoming the next Twitter.

“You’re starting to hear it: ‘It’s a new world order.’ Apparently the sun is going to rise in the west because of Twitter,” said Timothy Connolly, a New York money manager who teaches classes in investment analysis and has posted a steady stream of skeptical tweets about Twitter’s stock. “It’s absolutely beyond ridiculous.”

Twitter, which has triple-digit revenue growth but no profits, is trading at a much higher valuation than proven Internet powerhouses like Facebook and Google. The company has released no major news or financial information since its initial public offering that would shape investor perceptions about the company.

But that has not stopped investors’ exuberance about Twitter’s potential to eventually bring in billions of dollars from advertising, coupled with Wall Street’s penchant for hopping onto any fast-moving train, from propelling the shares to nosebleed levels.