Einstein’s theory of relativity shows us that time isn’t constant,it stretches or contracts based on speed and gravity. But ...

The speed of light is constant, or so textbooks say. But some scientists are exploring the possibility that this cosmic speed limit changes, a consequence of the nature of the vacuum of space.

The speed of light in a vacuum, usually denoted c, is a fundamental constant central to much of physics, particularly Einstein’s theory of relativity.

In fact, variable speed of light theories have long been used to try to explain everything from dark energy to gravity itself. Let’s explore how constant this fundamental constant really is. 07 ...

In a nutshell, the constant speed of light wouldn't be able to explain why the universe today, as large as it is, is homogeneous in density, or largely uniform everywhere.

Many things in life are constant. The crushing sense of disappointment after finishing a bar of chocolate, for example. The unpredictability of 2016. And, of course, the speed of light. But, wait ...

When you purchase through links on our site, we may earn an affiliate commission. Here’s how it works. The speed of light traveling through a vacuum is exactly 299,792,458 meters (983,571,056 ...

The speed of light may not be constant, a possibility that could have broad implications for fields of cosmology and even astronomy, say physicists. Skip to main content. Open menu Close menu ...

The speed of light is constant, or so textbooks say. But some scientists are exploring the possibility that this cosmic speed limit changes, a consequence of the nature of the vacuum of space.