<p>Stephen Wolfram answers general questions from his viewers about science and technology as part of an unscripted livestream series, also available on YouTube here: https://wolfr.am/youtube-sw-qa</p><p><br></p><p>Topics: Why perpetual motion machines fail - What might be driving the universe's expansion - How particles emerge from the structure of space - Entropy and the Big Bang theory - How temperature can become negative</p>
