We look around and find this world simple, beautiful and very enjoyable. We enjoy tides and beaches, stare at the moon, wish on falling stars, take a sunbath, smoke pot, fall in love, kill, evolve and breed without wondering about the underlying chaos and uncertainty in the fabric of our existence. I always wondered why we are here or do we have a purpose? Or is it just by a mere chance? One magical thing always kept me baffled as I thought about this universe. How the finely tuned universal constants came together to create a universe of this magnitude and complexity yet support the evolution of an intelligent life on earth? What if the value of those constants were slightly different? What would be the implication on the evolution of life?
Thankfully, those constants are what they are and not any bit different, or we wouldn’t be here wondering about the origin and evolution of our very own existence.
What constants am I talking about? What are those and why should we care, we are here and that’s all we always cared about? Doesn’t it prove a divine creator turned few knobs to fine tune those constants to their values, so we can exist and provide Him with His daily dose of worship?
Well, don’t get confused when I say ‘Fine Tuned’. It’s not about some divine mathematician sitting there and doing some complex calculations to come up with those values of universal constants. Here, by fine tuning I mean how naturally the laws of physics set these Constants in a universe(probably universes) and fortunately we are in the one which suits our existence. Frankly, the number of these constants vary from physicist to physicist but I’ll try to briefly discuss about most of them.
Following are those widely accepted Universal constants and few dimensionless constants as suggested by Martin Rees(Physicist):
force-particles
1. Speed of Light(c): It’s value is around 3,00,000 km/s, the fastest ‘thing’ in this universe. No matter what we do, we can never exceed this value. It’s like a universal traffic police, always keeping you in check and reminding you of your limits.
2. Gravitational Constant(G): This is responsible for keeping things in their place, like moon around earth, earth around sun, sun within a cluster of stars, stars around a giant black hole which is at the centre of milky way. This ‘G’ also keeps this whole universe from blowing apart.
3. Plank’s Constant(h) is one of the most critical universal constant. Even the slightest change in its value can drastically alter the whole nature of reality.
4. Weak and Strong Nuclear forces which provide stability to atomic and subatomic particles, thus to everything that exists.
5. Ratio(N) of the strength of gravity to that of electromagnetism which governs the balance required to keep these two long distance forces interfering with each other, say avoiding moon to repel apart from earth and keep in its orbit.
6. Strength(ε) of the force binding nucleons(proton and neutrons) into nuclei thus making the subatomic universe a little less chaotic and stable.
7. Relative importance (ω) of gravity and expansion energy in the Universe
8. Cosmological constant (λ), defines the strength of a force against gravity which is not because of some particle(mass, charge etc.) but is built into the very fabric of space-time.
9. Ratio(q) of the gravitational energy required to pull a large galaxy apart to the energy equivalent of its mass
10. Number of spatial dimensions in space-time(x,y,z) and a temporal dimension(Time). This very much defines and stabilizes the reality as we know it.
Universe with random constant values would be highly hostile and yet no less than a unpredictable beauty. If you have to create a Universe using random values then just imagine the number of universes you can create? But what if these constants were little different in the universe we live in?
Universe with random constant values would be highly hostile and yet no less than an unpredictable beauty. If you have to create a Universe using random values then just imagine the number of universes you can create? But what if these constants were little different in the universe we live in?
Let us take a scenario where, in a Universe some of the laws and constants of nature are quite different. Say if the value of Light Speed(c) is very much smaller than its actual value. If you are driving along a street you can see the nearby things getting shorter and smaller because the things you observe are due to the light bouncing off them and when it reaches you is relative to your speed.
If the value of planks constant is greater than what it is then things will be all fuzzy because of Heisenberg’s Uncertainty principle. It would be impossible for hunters to shoot in such a fuzzy world, they won’t be certain about the position and speed of their hunt at the same time.
If the magnitude of strong interaction were slightly weaker than it actually is, the number of stable elements would be smaller and you will be radioactive because the iron in your blood cells won’t be stable. If the strong nuclear force were 2% stronger than it is, Hydrogen would fuse so easily that it is likely that all of the Universe’s hydrogen would be consumed in the first few minutes after the Big Bang and there won’t be stars as we see them, there won’t be any life as we know it. If there would have been 4th spatial dimension(say u) in addition to x,y,z then gravitational force would have been very weak, there would have been no stable elliptical orbits for planets to revolve around their star, would have either collapsed into star or thrown away.If value of Cosmological constant (λ) were greater than it is, our universe would have blown apart shortly after big bang (when this all started). These are just few situations when we alter the values of those constants, in a broader term the chances of evolution of life in such a hostile scenario is highly improbable. We should find ourselves lucky about the apparent fine-tuning which is no less than a miracle.
We have seen what the world would be like if the Universal constants were different. But the question is how these values evolved? Is there any natural or scientific explanation? Why not some supernatural God or maybe some intelligent designer? Highly evolved Aliens? Or is it just a Coincidence?
It is possible that some of these constants are something like the ratio of circle’s circumference to its radius. it may turn out that there is only one possible way for a universe to be. Far from a creator needed to twiddle to the knobs for constants, there are no knobs. This has been a center of debate between physicists and theologians. There are many theories out there trying to answer this mystery of fine-tuning . Few of them are Alien Design(not God), Oscillatory universe(Parallel Universes), Bubble Universe and few more . In next post we will go through most of them and eventually to arrive at a point where we can ‘safely’ say ‘Nothing is Real’.