Amazon.com Inc. said Tuesday that it will add 2,000 technology jobs in Boston with the expansion of the company's Boston Tech Hub. Jobs will cover areas like speech science and robotics engineering. Amazon will move into a new 430,000-square-foot space to accommodate the new hires. The new office will open in 2021. Amazon opened a Cambridge corporate office in 2013, which is the anchor for the Boston Tech Hub. Amazon has more than a dozen tech hubs around the country. There was chatter last week that Boston might be a finalist in Amazon's search for a second headquarters location. Amazon shares are up 34% for the year to date while the S&P 500 index is down 1% for the period.