Tune the universe
The dials are set just right.
The universe runs on a handful of numbers: how hard gravity pulls, how tightly atoms hold together, how much energy a star gets from its fuel. No law we know of makes them what they are. Yet nudge almost any of them a little, and there are no stars, no chemistry, no you. Try it.
- Life ✓Gravity
Between two protons, gravity is 1036 times weaker than the electric force. Stars and planets have room and time.
Much stronger, and by Martin Rees's calculation only a small, short-lived universe could exist.
- Life ✓The strong force
It glues the cores of atoms together, so carbon, oxygen, and iron can exist.
A little weaker, and the periodic table would be nothing but hydrogen.
- Life ✓Electromagnetism
Stars forge both carbon and oxygen. Life needs both.
Stars would make carbon or oxygen, but not both.
- Life ✓Nuclear efficiency
When hydrogen fuses in a star, 0.007 of its mass becomes energy. That keeps stars like the Sun burning and leaves hydrogen for water.
Martin Rees calculated the hydrogen would have fused away soon after the Big Bang. No water, no stars like the Sun.
Now the hardest dial of all: dark energy, the push that makes space stretch faster and faster. Our best theory expects it to be up to 10120 times bigger than it is. Too strong, and space flies apart before a single star forms. Negative, and everything collapses. Find the window where stars can shine.
Negative: the universe collapses back on itself before life can form.
This is the whole range our best theory expects. The life window is in here somewhere.
Zoomed in ten billion times. Still too thin to see.
Zoomed in more times than there are stars in the observable universe. Still nothing.
More times than there are atoms in the observable universe. Still nothing.
Zoomed in 10120 times. There it is. Now drag the dial into it.
Take that in. 1 in 10120 is a 1 followed by 120 zeros. Hitting it by luck is far harder than picking one marked atom out of every atom in the observable universe, about 1 in 1080. Even cautious estimates put it at 1 in 1055. And that's one dial of many.
So why are the dials set this way?
Necessity? No known law of physics forces these values. They could have been otherwise.
Chance? Only with a multiverse of countless universes, and there's no evidence one exists. As the physicist Luke Barnes puts it, “‘Multiverse’ is not a magic word that will make all the fine-tuning go away.”
Design? Someone chose the settings. That's where these scientists landed.
What the scientists said
Intelligent design, as one sees it from a scientific point of view, seems to be quite real. This is a very special universe: it's remarkable that it came out just this way. If the laws of physics weren't just the way they are, we couldn't be here at all.
Fine-tuning can't tell you God's name. It does point to a universe set up on purpose, by someone with the power to do it. The Bible names him:
The heavens declare the glory of God; the skies proclaim the work of his hands.