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Space Hero

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My newest hero is Commander Chirs Hadfield.  What a man! I had never known or heard of him until about two days ago. I tuned in to one of my favorite radio shows, Fresh Air, and I caught Terri interviewing Commander Hadfield.  It was such a riveting interview. In it,the  Hadfield describes his space walk, tethered to the space ship, and orbiting the earth, with a glorious view of the earth on one side and the black quiet emptiness of space on the other,  at a breathtaking speed of about 17,500 miles per hour!  He is so brilliant, “lyrical”, and eloquent in describing his experiences as an astronaut.  I went back and listened to the whole interview again. You can find it   here .

Astronaut Chris Hadfield Brings Lessons From Space Down To Earth .

Ira Flatow also did an interview with him on Friday …

Chris Hadfield’s Lessons From Life in Orbit

and so did  Marco Weman

Astronaut Chris Hadfield shows childhood dreams can come true

All three interviews while similar have slightly different takes but well worth listening.

Here is a link to his  beautiful and moving rendition of David Bowie’s “Space Oddity” [18M+ hits ]

There is a lot more…on YouTube….tears in space, sleeping in space…etc., Entertaining and educational for kids and adults alike.

He is a complete package….astronaut, musician, scientist, guinea pig (NASA is studying bone density loss and recovery), author,  and a fantastic human being. A true role model…..I have ordered his book – An Astronaut’s Guide to Life on Earth. Can’t  wait to read what he has to say.

 

 

 

 

 

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Written by asterix98

November 2, 2013 at 5:52 pm

Sagan’s lectures on natural theology

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Ann Druyan’s introduction to  Carl Sagan’s – Varieties of Scientific Experience, is wonderful. Just like he does in the lectures proper, she challenges us to open our minds to critical thinking….”what is wanted is not the will to believe, but the desire to find out….we are spiritually and culturally paralyzed, unable to face the vastness [of space], to embrace our lack of centrality and find our actual place in the fabric of nature…” Contemplate this image. The earth is but a pale blue dot afloat in the immensity of the universe…a small speck situated in a solar system within one of a hundred billion galaxies.

The book is a compilation of Sagan’s Gifford lectures on natural theology. As Sagan notes, natural theology is “…everything about the world not supplied by revelation”.

The lectures are organized as chapters. It begins with a chapter titled Nature and Wonder: a reconnaissance of heaven. It is a beautiful tour of what is known about the cosmos. Sagan introduces us to the vastness of the universe and gives us a sense of scale and our relative position in the scheme of the universe. He also tackles superstition [a belief without evidence], and operationalizes the definition of religion [ “binding together from Latin] so essentially science and religion are after understanding the interconnectedness of things.

In the next chapter – The retreat from copernicus – loss of nerve – Sagan takes on creationism, the anthropic principle [interpreting the world in human metaphors], and also gives us a sense of what the lack of centrality for Earth in the cosmic order really means.

Organic universe is another brilliant discussion on the chemical makeup, universal laws and such.  We can see a sample of his wit here .”…so as science advances, there seems to be less and less for God to do. Of course its a big universe, so He, She or It can be gainfully employed in other parts….”  I really like the notion of the  “God of Gaps”, ie., whatever we cannot explain is attributed to God.

The next lecture makes a case for why extraterrestrial intelligence may exist. Sagan also notes that whether it exists or not, it is still hugely informative because it says something about our loneliness. This is followed by a thorough debunking of “extraterrestrial folklore”, the claims of UFO sightings and visitations from aliens, that have been reported in the media over the years.

In the God hypothesis discussion, Sagan provides an operational definition of God, take us on a quick tour of the world religions and their claims and postulates. He then , with scintillating wit (there are many examples throughout), systematically deconstructs these ideas. He also put forth arguments on why God as an OmniX being is not internally consistent.

In the religious experience – he questions the efficacy of prayers, discusses the influence of hormones on human behavior, and coins a God molecule – “theotoxin” he says (tongue in cheek) “would be biasing the issue too strongly….”

In the next chapter, Crimes against creation, he is very concerned with the possibility of a nuclear winter, but in general, it can be interpreted as a general concern for the earth and its inhabitants. Elsewhere, he pleads, “… if you disagree with another human, let him live. There is nowhere in the hundred billion galaxies you will find another…”

The last chapter “Search” – anticipates the world is flat state of affairs. We started as hunter gatherers in small groups, have grown into nation states, now technology, communications, and transport have blurred those boundaries even further. In short, we have to think of ourselves as world citizens. Sagan urges us to think critically on all matters and have compassion for fellow world travelers.  He asks why there is no equivalent of a 11th commandment – thou shalt learn….

In short, if I have not already conveyed it, this compilation of Sagan’s Gifford lectures is pure cognitive pleasure. Well worthy of earning a prominent place on your bookshelves. There are others who, in recent times, have gone after organized religion, such as Dawkins or Harris, but their tone has been angry and sometimes, completely intolerant. Here, I see, Sagan, like an explosives expert, placing the bombs through beautiful, calm, cogent, and brilliant arguments, strategically on the edifice of organized religion. The image I am striving for here is the demolition of tall skyscrapers that crumble in a heap with little or no collateral damage.

Written by asterix98

May 6, 2012 at 10:15 pm

Multiverses

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I finally got around to listening to a really wonderful interview with Brian Greene on Fresh Air. 

Some of the themes discussed

  • String theory is science bordering on science fiction, but some science fiction does become science fact over time.
  • multiverse – multiple universes, our universe is one of many universe populating a grandiverse
  • Possibility of the same interview in another universe?
  • Universe is infinitely big, but matter can only arrange itself in a finite number of ways. (deck of cards example)
  • Assumes physics on earth holds everywhere in the cosmos (support : we can look out to billions of light years and it all seems to hold)
  • origin and evolution of cosmos – (a variation on the multiverse theme) inflationary cosmology. big bang theory. Does not tell us what happened at time zero. Repulsive gravity. many big bangs.creates many universes.does not rule out that the same laws hold in these other universes.

(My color commentary)

Seemingly crazy idea justified as working with the arcane math inaccessible to common folk(math is a sure footed guide to how the universe works). Visiting  these parallel universes possible through mathematical journeys.

Following this there is a really intriguing discussion on quantum mechanics and its ramifications.

  • quantum mechanics. not relevant to larger things but is important at the smallest scale
  • probability vs Newtonian determinism
  • QM says you can only predict the likelihood of where a particle will be. How do we go from probability to a definite outcome. Physicists do not understand this yet.
  • Hugh Everett postulated really two parallel universes (one particle here and one there).Every experience is based on particles. Every possible reality happens in its own universe.

The multiverse notion is highly controversial.Because there is no way to interact or prove multiverse existence.

A ginormous revolution if multiverse theory is  true. (following the trajectory of copernican revolution to discovery of  multiple galaxies and our sun being one of billions of like stars) leading to “fantastic upheaval of our understanding.”

There is also an excellent discussion of  the macro scale (theory of gravity) to microscale (quantum mechanics) and where the twain shall not meet necessitating string theory. The discussion sort of culminates with the grand unknown of all “What is time?”

All in all, highly recommended listening. Guaranteed 34 minutes of intense cognitive pleasure. (Terri Gross is a really fabulous interviewer too).

As I was listening to it, I couldn’t help thinking how theologians and charlatans (at least the eastern sort) must be licking their chops, falsely assuming that multiverse theory affords them some scientific fodder, to fit the fantasies of yore and recast them as very deep and prescient understanding of the nature of the grandiverse.  The Sai Baba like and Siddha believers, if they latch onto this, will go on a rampage treating this new enlightment as complete validation of their far out beliefs. I can also see the now spin doctor Deepak Chopra profiting even more from weaving this into his healing sermons.

I also couldn’t help thinking our personal lives span many universes depending on the role we play. Also, our mental universes, inspite of the same physical reality, are sufficiently different, that they may as well be independent universes.

At any rate, all of this thinking is as far out as the science itself.

I am reminded of three quotes I heard somewhere on the radio or read it someplace.

Time exists so that everything does not happen at once. Space exists so that everything does not happen to me.

and

Life is what happens when you are making other plans.

Written by asterix98

March 4, 2011 at 3:46 am

End of days

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Lecturer: Dr. Rita Wechsler

A very entertaining lecture. Wechsler likes to deal with very large time scales (on the order of billions of years) and it was exteremely interesting and fun. I liked the way she kept referring to “stuff” when dealing with dark energy/dark matter.So here goes…..

  • Till about a 100 years ago, the prevailing view in Cosmology was that the universe was static
  • In fact, Einstein added a term in his theory of general relativity (which naturally allowed for expansion and contraction) to make it static!
  • Galaxies, I think, are also known as spiral nebulae
  • Hubble used spectrum to measure velocities
  • V= Hod (velocity is proportional to distance – H0 is the Hubble constant)
  • More matter in the universe implies expansion is slower. If we measure expansion rate, the age of the universe can be calculated
  • Our universe is 13.7 Billion years old !!
  • Big Bang
    • Universe is expanding
    • past universe much denser
    • denser means hotter in the past
    • implies our universe is now cooling and diluting over time

Time scale cheat sheet

  • Age of the universe : 13.7 Billion years
  • 1st Galaxies              : 13.3 B
  • Milk Way                  : ~12-13B
  • Sun                            :  4.6B
  • Earth                         : 4.5B
  • Life on Earth            : 3.8B
  • Mammals                  : 200 Million years
  • Humans                     : ~ 400K

Lets stop here for a moment (actually a sec) and put this perspective.  If the Universe were 1 sec old, our existence on this Earth as a species has lasted a mere 30 microseconds. If you and I were to live the full 100 yrs, it is a mere 7 nano seconds since the dawn of Time. Again, 7 nanoseconds!!

I think somebody asked, “where is the center of our universe?” . Wechsler answer was, Big Bang happened at a single point. We are at the center of our observable universe (limited by the distance light has travelled).

There was a fun section on how life on earth may end. Here are some interesting tidbits

  • Chances of the earth being destroyed by an Asteroid are 1 in 700000 over a lifetime. In fact, Congress has mandated that all asteroids upto 140 meters (?) in diameter be catalogued and monitored
  • Gamma ray bursts – would completely fry the ozone. Burst within 10000 light years would be dangerous. But the odds are only 1 in 14Million over a lifetime. So no real worries there!
  • Dusty Milky Way – could block our sun. Imagine what could happen. Chances – 1 in 30Million years. Rest easy.
  • Death of our Sun – He is middle aged now. Burning hydrogen and getting hotter. Also getting brighter by 10% every Billion years. In 6 Billion years our Sun will be dead. Long live the Sun!

The Milky Way has the brightness of 30 Billion suns !! What kind of sunglasses would you need if you lost your way and ended up near the Milky way?!

In about 3 Billion years, the Milky Way will collide with Andromeda. We watched an exhilarating video simulation of this event . Upshot is that the collision will completely upend the spiraling Milky Way, which means we are also in trouble.

The expansion of the Universe is accelerating. This is contrary to most expectations.

Distinct from dark matter there is this stuff nobody really understands called Dark Energy.

Interestingly, the make up of the universe is

  • 4% atoms (0.4% stars, 3.6% gas)
  • 26% dark matter
  • 70% dark energy

95% is not in the periodic table or in the standard model !!

Written by asterix98

November 24, 2010 at 6:52 am

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