In the beginning, things started small, then, as time passed, space expanded and the scale of everything got bigger, so that it eventually came to be the size of the gargantuan proportions we see today. This, in a nutshell, is how physicists like to describe the evolution of our universe, but it may equally be taken as a reasonably accurate description of the evolution of physicists' books about the universe.

In the beginning (back in 1988) there was A Brief History of Time, Stephen Hawking's surprise bestseller that catapulted cosmology onto coffee tables everywhere - boldly displayed by intellectuals and hipsters alike. Though Hawking's infamous volume may be the most unread book ever, it had the virtue of brevity, at a modest 192 pages. A decade later, Brian Greene's The Elegant Universe, which updated the cosmic picture from the standpoint of string theory, ran to 448 pages, even as the size of the type had shrunk. In January came Simon Singh's Big Bang, a 532-page account of physicists' quest to understand the origin of the universe, and now Roger Penrose's The Road to Reality extends the story to 1,136 pages.

The past several decades have been immensely fruitful for theoretical physics at both the subatomic and cosmological levels.

But does physics really have this much more enlightenment to offer? The ever-inflating-physics-book phenomenon calls, I think, for a deeper explanation, one that has less to do with the advance of science than it has will with the 'celebritisation' of science publishing.

Before the mid-'80s, physicists were essentially nerds. Worse than that, they were associated with weaponry. As a physics student in the late 1970s, I well remember the disgust on people's faces when I told them my chosen subject. Then came Fritjof Capra's The Tao of Physics, Gary Zukav's The Dancing Wu Li Masters and Paul Davies' God and the New Physics, all of which cast physics as a mystical search for Truth. A Brief History of Time, with its closing reference to "the mind of God," solidified this transformation in the public psyche and installed Hawking as the high priest of science - in the process, selling some 10 million copies.

Since Hawking, the publishing industry has been trawling the halls of academe for further stars. No one fits that bill more than Roger Penrose, emeritus professor of mathematics at Oxford University and the co-author of Hawking's original papers about 'singularities' (which include black holes).

Penrose is also the author of the controversial book The Emperor's New Mind, which claims that consciousness can be explained by quantum mechanics. Not only is he a great physicist, he is also a gifted mathematician who has developed the theory of 'twistors' (six-dimensional entities that may explain the basic structure of space and time).

So it is hardly surprising that he has been signed up for what its publishers, with Hollywood-style hubris, call "a major publishing event". By volume and weight, The Road to Reality is certainly a humongous event. And what do we get in our 1,136 pages? Just about everything, it seems.

Penrose's goal, as he tells us on his opening page, is to educate his readers about "the underlying principles that govern the behaviour of our universe," and to that end he begins by taking us back to first principles. Not to the early 20th century and Einstein's theory of relativity, or even to the 17th century and Newton's laws of motion, but to the 5th century bc, to Pythagoras and his famous theorem about right-angled triangles. Over the next thousand pages, the reader is treated to a virtual university education in mathematical physics.

But what of the potential reader for whom the phrase "twistor sheaf cohomology" is likely to induce a sense of apprehension, if not outright terror? At the start of the book, Penrose tells us he has eschewed the standard publishing advice that for every equation, his sales would drop by a half. He expresses the belief that most people's mathematical ability is considerably greater than they imagine and, with patience, anyone can understand the glittering edifice that is modern physics.

The myth of the non-maths brain is one of the more noxious notions in our culture but it's true that people who don't acquire mathematical skills while young have difficulty doing so as adults … at least at the level Penrose is proposing. To present The Road to Reality as accessible for most readers would be utterly disingenuous. That said, this book is a brilliant resource for anyone who wants to know the influences behind physicists' search for a description of the material world. You may not advance past the preface, but there's no more concentrated a package of vicarious braininess. It will radiate an aura of intellectual uplift to the entire neighbourhood.

I hope for Penrose's sake that it at least sells well enough to become one of the world's foremost unread books - it is certainly among the greatest.