Freitag, 28. Juli 2017

A lesson of time: From the Big Bang to human extinction.

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In the last two months I was able to learn with my eldest kid (4) about the universe, planets and dinosaurs; main subjects in his daily conversation. Reading his books and visiting (many times) museums I recalled what we all already know but not think deeply about its meaning: how old is our universe, why dinos died and what are we doing here.


We learned that the universe is 13.7 billion years old. To put it in numbers 13.700.000.000 years and that it all started with a big KaBoom! (Big Bang). Since then a lot has happened to put humans where we are now. What is interesting is that we are definitely new in the history of the universe and we still think however that we are central to it. Worsely, we defend blindly (even with our own lives) our selfish mythological beliefs about who created all things.

Why I say that we are the “new ones” here? Let’s pretend that the universe has exactly 100 years old, just like a healthy and attractive centenerian that seems will live much longer.




 At the age of 1 year (200 million years after the Big Bang) galaxies developed, but it is only at the age of 67 that the planet earth was formed (9150 million years after the Big Bang). At this stage the planet Earth was still very immature for living beings.

Multicellular organisms (Ediacara fauna)on Earth are estimated to have occurred around 13.08 billion years after the great explosion. Translated to our centenerian universe it means that only at the age of 95 life could arise on at least one of the trillion planets of our universe, in planet Earth.

Dinosaurs showed up 235 million years ago (at the age of 98 of our centenerian universe) and they ruled the Earth for not less than 160 million years (that’s about more than one day for our 100 year old universe).

The 5th mass extinction of living beings on planet Earth took place 65 million years ago. Afterwards humans, as we know them, started to develop from apes (Hominoidea). Miss Universe is now 99 years and there are only 53 days to go for her 100 birthday.

Homo sapiens (humans) seem to appear 20 hours before the 100th birthday of our centenerian universe (fossils were found in Morocco dating back to 300 thousand years ago. Link here).
  
The chronology of events in the Universe and in our planet is intensively studied, considered reliable and teached in school and university books. It is constantly updated and either proved correct by scientific methods or at least by mathematical approximations to which we don’t want to go much into detail (for more information please apply to the nearest Paleonthology, Astrophysics and/or Particle Physics course in your town). However, humans, right from their beginning, believed and still believe on supernatural and mythological forces that created the universe, earth and mankind. Each religion (although just few minutes old in the history of our centenarian universe) had, has and will have its own version of the origins; and their followers, as in the past, are not willing to accept other explanation than their own.
  
To our fortune, there are people in our planet who are not conformist with fairy tales and are curious enough to investigate and go deeper into the origin of things. Without them we would still believe that the Earth is flat, or that it is the center of the universe, or that humans were created from mud, or dust or corn or from a male human rib.
  

  
 It is worrying that we will almost for sure not be as long in this planet as dinosaurs were (160 million years). In our very young existence (300 thousand years) there are estimates pointing to human extinction to year 2600 if there are no changes in our climate policies and the current exponential population rise 1 .
Based on these predictions, Stephen Hawking, one of the greatest physicists of our time, prompt us urgently to seek new worlds and colonize them if we want to avoid extinction in the near future.



For his whole lecture at the Starmus Festival 2017 (Norway) see here:

 https://www.youtube.com/watch?v=lpG5P6ugeeI

It’s a topic with many more questions that we might never be able to respond. For example:
What about the time before the Big Bang? Time does not count there?

Maybe is our universe a part of another one, or one of many. And what would happen when two expanding universes encounter each other? (Likely total annihilation). In fact, a “Multiverse” is a possibility that is supported by the M-theorie (which I have no clue what is but astrophysicists might understand it)
Even if we don’t dissapear in the next thousand years, we might in few million years with the upcoming waves of mass extinction (as it happened before 440, 375, 250, 205 and 65 million years ago) or the possibility of a cooling down of the universe or an explosion of our sun among other astronomical catastrophes. Thinking of these we should probably aim to make a backup of all the information we generated in the last 300 thousand years. From “how to do fire” to “how to cook spaghetti” should be stored for future residents living in this or more likely in other planets.

Now, if you excuse me, I need to use my very limited time in this Earth for something else (My hopefully >80 years are just about 18 seconds time of our 100 year old Miss Universe).

Persistence of memory, Salvador Dalí 1931

References
1.       Hawking, Stephen. The Universe in a Nutshell. 2001
2.       The Museum or Natural History. Vienna, Austria. http://www.nhm-wien.ac.at/