Friday, July 19, 2013

Big Bang, Dark Matter, Anti-Matter and Wimps: How Astrophysics adds to the Miracle of Existence


Reflected lights from stars in the universe
 I almost missed out on a brilliant talk by astrophysicist Hitoshi Murayama presented at Science World last week. I had found out about it too late (a day in advance) and the tickets had already evaporated into thin air. But thanks to technology I was still able to witness and follow it closely via live streamline. I may not have been physically there, but all my other parts were present and attentive.

Murayama tried to answer two seemingly straightforward questions that generally make my head spin in myriad directions. The first half was devoted to the task of making dark matter accessible to hobby-horse math-deficient astro-enthusiasts like me. Dark matter, as its name implies, is something that we cannot see, not even with highly capable telescopes.

The reason for this is that it has such a strong gravitational pull that not even light can escape its reach. Scientists evidently can only know about it by inference, by analyzing how it distorts its environment around space. By looking closely at its “neighbors,” they can calculate various qualities and dimensions about dark matter (don't ask me how).

Now it turns out that my physics class in high school was wrong in claiming that the universe is mostly made up of atoms. In fact, about eighty percent of space is made of this mysterious and invisible dark matter. It is indeed essential for our survival, the "mother" of our existence as Murayama calls it. We are not only spinning unawares with our constantly revolving Earth at about 465 m per second, but our whole galaxy, the Milky Way is moving at about 220 km per second. Per second!

And generally, that would make the galaxy spin out of control, or at least the gravitation would be strong enough to dislocate its position, to make it spin out of its orbit, which would make us disappear somewhere far far away in our universe, perhaps next to the creatures of Star Wars. That is, if it were not for the pull of our friend dark matter, no not Darth Vader although he was mentioned and alluded to various times during the talk. So thanks to you a bunch, dear dark mother for keeping us compact and together!

The second part of the talk was about an even more mysterious and misunderstood matter, in fact, the opposite and mortal enemy of matter itself, anti-matter. Murayama explained how, contrary to popular belief, the creation of sizable anti-matter (such as 1 g) is currently not feasible and that Dan Brown's Angels and Demons is simply wrong about the whole issue. 

It would cost an unbelievably large amount of money (believe me really really vast amounts of dough) to create a substantial amount of anti-matter. Yet if it were possible, it would be quite interesting and beneficial to our science since it would be hundred- or thousand-fold times better and more effective than gasoline.

Yet what is anti-matter? While I think I sort of understood dark matter, anti-matter is more difficult to get your head around. In fact, when matter meets anti-matter, they both dissolve leaving a blast of energy. So if you meet your identical anti-matter version of yourself, do not shake hands! In fact, run as fast and far away as you can!

Going back to the beginning - we are talking Big Bang era - we notice that matter and anti-matter existed in equal measure. That means that they would collide and explode each other mutually. That means we would have never existed if that had been the case.

So how did it happen then? It turns out that there is a secret ingredient to this atomic creation soup, namely neutrinos also known as Wimps (weakly interacting massive particles). They are neutral; while positive and negative electrons attract each other to their own demise, neutrinos simply look on as impartially as Switzerland. And it is to them, that we owe another part and our very reason of our current existence here. Thank you, dear father Neutrino! In fact, they may be right here with us as we speak because they can go through matter like water.

What can we take from this amazing lecture apart from knowledge and understanding? Well, for one, I marvel even more at our existence. The odds and probabilities seemed stacked against us, were it not for a miraculous interplay of various elements and events. The chances are indeed one in a billion or rather trillion that I should exist writing this and you, dear reader reading this!

The other surprising fact for me is that the telescopes today can capture images that are moments after the Big Bang. There is physical evidence for it! They cannot go further back because the hot soup will not allow them to get a clear picture, which is why they are experimenting with it at Cern.

Another breath-taking discovery or realization for me, or rather it dawned upon me more clearly during and after the talk is the fact that we are able to look into the past. Lights that reach us are already the past. For example, the sun rays we see are the state and position of the sun from about eight minutes ago. That is a small and generally known matter, but lights from stars that are light years away are from the not so recent past. Basically, we can watch and look at the past state of affairs and even get a glimpse of our previously mentioned Big Bang.

So if we went very far away from our earth, if we were on the “other side” so-to-speak, we should be able to see the dinosaurs roaming about. And should we move with light-year speed, perhaps one day using anti-matter energy, we could travel to the past. All these thoughts are obviously my own speculation and were not mentioned during the talk. But I am more than grateful that despite the odds against me of not finding a ticket, I was still able to listen in and learn from this wonderful talk by Hitoshi Murayama.

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