If the multiverse theory is true then there are many possibly universes out there. Many could be similar to our Earth with variations to human history as described in in the timelines created in this blog and other sources of alternate history. But human history is just one of the things that could be different. There may be a universe out there where the strong nuclear force is about 2 percent stronger than in our universe. There might be a few other minor tweeks to the laws of nature and this strange new universe would continue on its path.
The more powerful strong nuclear force would allow stable diprotons to form, overcoming the electromagnetic force that keeps them from forming in our world. In the earliest stages of this universe shortly after hydrogen atoms are created they quickly pair off and form diprotons. Thus before the first stars form the universe is filled with helium.
Fast forward billions of years. In our section of the universe one solar mass of these atoms along with trace elements from the first generations of stars forms into the Sun. It is not like our sun, however. It is large and red, appearing in many ways like our star will look when it hits an age of nearly 10,000,000,000 years. But this star is born burning helium instead of hydrogen. after 600 million years much of its gases have drifted away and the remainder of the star has formed a what dwarf with a 0.6 stellar mass.
For the next four billion or so years as this timeline catches up to the point in time we are in ours the white dwarf slowly cools. Its surface is still over 2,000 degrees on the kelvin scale.
The Earth, or the charred sphere of silicon, iron, and carbon that is in an orbit close to where Earth would be, is a cold and tidal locked planet with no moon or life. Life as we know it is impossible in this universe. The lack of hydrogen makes many molecules impossible including a rather important one we call water.
With no life this timeline tends to have a long and comparatively dull history. Its Stelliferous Era will be much shorter than the same era on our timeline. And while our white dwarf sun is still rather warm the first silicon nitride molecules are forming. The chances of silicon life forming, even a trillion years in the future on this star, are nearly impossible. Silicon can create fewer complex molecules than carbon and the lack of hydrogen limits possible molecules even further. However given the huge periods of time involved and the unknown variables in this altered physical universe perhaps during the star's 100 quintillion year life something may eventually be born.
What that life may look like, and how it would function on a world with a mass 600 times that of Jupiter inside the volume of our own Earth, and given the higher mass silicon based life would have compared to carbon based life, it is impossible to speculate.
In any event the solar system by the equivalent of AD 2014 is lifeless, and will continue to be lifeless for the foreseeable future.
The photo in this post is of the white dwarf Sirius. Photo by NASA 2005, and modified by me.
Some of the concepts in this article, including the speculation of life on white dwarf stars in the extremely distant future I got from the book The Five Ages of the Universe by Fred Adams and Greg Laughlin. I've only skimmed parts of the book but I intend to give it a proper reading this summer. Fascinating stuff!
While looking into the possible outcomes of an increase of the strong nuclear force I found many theorized possibilities. I picked elements I liked and assumed that other minor changes to other physical laws would pick up the slack.
While silicon based life seems unlikely I've been listening to the audiobook version of Weird Life by David Toomey and heard mention of silicon based life working better on the colder side of things than the extremely hot. Some details can be seen in this Wikipedia article on Carbon chauvinism.