Book Reviewed: Not Even Wrong: The Failure of String Theory and the Search for Unity in Physical Law for Unity in Physical Law by Peter Woit

A quarrel with physicists being lost in math This is an interesting book by the Columbia University physicist Peter Woit who started a war of words with string physics community. String theory is purely mathematical and speculative that lacks testable predictions. The theory is largely unverified despite that it attempts to unify theory of relativity (physical reality at large scales) and quantum physics (physical reality at subatomic scales). The quantum field theory explains the behavior of elementary particles, and three of the four forces of nature. The Einstein’s general relativity explains the fourth force, gravity that becomes relevant at much larger scales. These two theories are logically and mathematically incompatible. String theory proposes to solve this problem by replacing elementary particles with strings as nature’s most fundamental entities. Therefore a “Theory of Everything” was needed to fully describe the physical reality we observe and experience. But string theory, unlike Einstein’s relativity, is not a specific set of equations, but rather a framework, or a class of equations of a particular style. Since string theory is not experimentally verified, the author calls this a failure, and criticize this as arrogance of physicists for promoting this for the last four decades. He has urged federal agencies like the National Science Foundation to cut funding for research in string physics. After more than a decade, he still thinks string theory is a gory mess. Most string theorists have gone back to their work undeterred by Woit’s criticism. Some compared him to a terrorist and even called an “incompetent, power-thirsty moron” and a “stuttering crackpot-in-chief.” This is an odd mix of intellectual jousting. His moderated weblog on string theory and other topics titled "Not Even Wrong" is still active on his Columbia University webpage. It continues to be widely read by physicists and mathematicians and still open for debate. Part of the book feeds on drama. Superstring theory explains things like multiverse and brings in new ideas for the fact that space and time is not limited to one universe such as ours. Space can expand and contract at much faster speed than the speed of light, and it does not require energy for its expansion. In addition, mathematical correspondence discovered by Princeton physicist Juan Maldacena implies that string theory has deep mathematical connections to quantum field theory. Peter Woit doesn’t give enough credit to a whole bunch of interesting things about quantum field theories that we’ve learned from string theory. I caution that some of the chapters are technical but there is also interesting take-home message from this book. His most recent blog written on Marc h 24, 2021 still makes an interesting point.