He interviews notable scientists about their fields of research and lays out his vision of coming developments in medicine, computing, artificial intelligence, nanotechnology, and energy production.

Kaku contrasts Verne's foresight against U.S. Postmaster General John Wanamaker, who in 1893 predicted that mail would still be delivered by stagecoach and horseback in 100 years' time, and IBM chairman Thomas J. Watson, who in 1943 is alleged to have said "I think there is a world market for maybe five computers.

Technology similar to BrainGate will eventually allow humans to control computers with tiny brain sensors, and "like a magician, move objects around with the power of our minds."

Kaku discusses the draining of oil on the planet by pointing to the Hubbert curve, and the rising problem of immigrants who wish to live the American dream of wasteful energy consumption.

Kaku suggests that nations are reluctant to deal with global warming because the extravagance of oil, being the cheapest source of energy, encourages economic growth.

Kaku discusses how Moore's law of robotics will affect the future of capitalism, which nations will survive and grow, and how the United States is "brain-draining" off of immigrants to fuel their economy.

Kaku stated that humans with an average economic growth may attain planetary civilization status in 100 years, "unless there is a natural catastrophe or some calamitous act of folly, it is inevitable that we will enter this phase of our collective history".

"[3] Reviewers at Library Journal have stated, "This work is highly recommended for fans of Kaku’s previous books and for readers interested in science and robotics.

[5] The Telegraph complained that "[Physics of the Future] is partisan about technology in a way that smacks of Gerard K. O'Neill’s deliriously technocratic vision of space exploration, The High Frontier.

Writing in Physics Today, physicist Neil Gershenfeld said that the book has “an appealing premise” but describes “a kind of future by committee” populated by “science-fiction staples”.