supernova results of Schmidt’s and Perlmutter’s groups, among other measurements, would require reinterpretation. Consequently, the universe might not be accelerating after all (or accelerating at a different rate than previously thought). This would again change our understanding of the cosmological constant.

Magueijo vividly describes how he and Albrecht developed this radical approach. Before they began the collaboration, Albrecht had a “lifelong obsession, the need to find an alternative to inflation.” The paper with Steinhardt had been Albrecht’s first (it was his doctoral dissertation work), so he felt it was time to examine other possibilities. Together, they explored the changes to the equations of physics needed to realize their idea. These turned out to be quite significant, considering that their theory contradicted not just general relativity but also special relativity. Even long-accepted formulations, such as Maxwell’s equations of electromagnetism, required modification. Nevertheless, they ardently pressed on—not knowing where the fruit of their efforts would lead.

Because of the controversial nature of the VSL hypothesis, the researchers had difficulty getting their findings published at first. Journal editors were reluctant to touch material that seemed to challenge the maxims of modern science. It took a year of revisions before their initial article was accepted. Even once their work was in print, many mainstream physicists shied away from it. Soon, this controversy was fueled even further by clashing experimental results pertaining to yet another natural “constant.”


The gravitational constant and the speed of light are not the only fundamental parameters that researchers have asserted could change with cosmic time. Another popular candidate for variability is the fine-structure constant, known by the Greek letter (alpha), which is basically the square of the electron’s charge, combined with other parameters, including the speed of light. Thus, either a changing

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