How big is BIG?

This morning I was looking at the Web site of the Sloan Digital Sky Survey

Fascinating stuff! SDSS is systematically mapping the entire sky, determining the positions, brightnesses and distances of celestial objects, to give a three-dimensional picture of the universe through a volume one hundred times larger than that explored to date.

They are obviously asking some basic questions. And getting answers, too. one question that really tickles my fancy is described in the article How big is big? Probing the conditions of the universe on the largest scales

Back in May 2006 researchers at SDSS announced the first measurements of galactic structures more than a billion light years across. Now that's getting to be sizable, isn't it!

Dark energy - the pressure exerted by empty space!

I would never have thought it, and even after reading it cannot begin to properly understand or appreciate this:

... dark energy is the pressure exerted by empty space. From a quantum mechanical perspective, empty space is unstable. According to statistics, photons and subatomic particles pop into the vacuum of space in a way that shows that "empty" is only an approximation: Space actually comprises a statistical soup of particles and antiparticles that are in a constant state of creation. Today scientists can demonstrate this by pumping the gases out of any empty chamber. After every atom has been pumped out, particles begin to percolate into existence in a process called vacuum fluctuation. ...

... unless the vacuum itself exerts the negative pressure observed, then the universe must otherwise be composed of as much as 70 percent dark energy.

Read more in the following Dr Dobb's article: Quantum Mechanical Theory Behind 'Dark Energy'?

How Wide is the Universe? - revisited

Way back in November 2005 I asked How Wide is the Universe? and have been pondering it every now and again since then.

Reading Bill Bryson's tour de force "A Short History of Nearly Everything" gave me some additional insights (see the early chapters).

And a few days ago I came across this link at Yahoo! Canada and the following article at www.space.com which I found especially informative on this matter:

Universe Measured: We're 156 Billion Light-years Wide!
If you've ever wondered how big the universe is, you're not alone. Astronomers have long pondered this, too, and they've had a hard time figuring it out. Now an estimate has been made, and its a whopper. The universe is at least 156 billion light-years wide.

In particular, it neatly outlines one aspect that beforehand I simply couldn't get me head around: why, if the universe is some 13 or 14 billion years old, its diameter in light years can be numerically greater than this. And it turns out that the above figure -- converted, of course, into distance in Light Year units -- cannot simplistically be regarded as the radius which, by being doubled, would lead to a diameter of 27 or 28 billion light years. And the key to this is explained thus:

... the universe has been expanding ever since the beginning of time, when theorists believe it all sprang forth from an infinitely dense point in a Big Bang.

"All the distance covered by the light in the early universe gets increased by the expansion of the universe," explains Neil Cornish, an astrophysicist at Montana State University. "Think of it like compound interest."

90% or 99.9% - The gene quandary

I was in two minds about whether to post this item here or in my Leave Good Enough Alone blog! But it is a pretty basic question, so here goes ...

Are we gullible or are we gullible? I was watching a TV science show special a week or so ago, and it made the oft-repeated statement that our human genes are almost identical, one person to another. And our genetic structure is remarkably similar to that of monkeys, and earthworms, and amoebae, and ... Or is it?

We watch ultra-modern analytic equipment doing its stuff, see gene structures flash across the screen, and listen to various genetics "experts" make their pronouncements. (And, if they're wearing white lab coats that makes them all the more believable!)

But, as of now in late 2006, how much do we really know about genetics and molecular biology and how much do we still have to discover?

These musings bubbled out of my unconscious today when I came across the Reuters article: New human gene map shows unexpected differences which starts off:

One person's DNA code can be as much as 10 percent different from another's, researchers said on Wednesday in a finding that questions the idea that everyone on Earth is 99.9 percent identical genetically.

Certainly intriguing, isn't it. I wonder where it eventually will all lead to.

About Asking the Right Questions

Here in Australia we have a national referendum every now and again, for such things as whether or not Australia should change from the monarchic model to the republican model.

Invariably -- as you'd expect from politicians -- the party in power in the federal government carefully crafts each referendum question in such a way that their preferred option is most likely to succeed: if you will, a variation upon the saying that "The devil is in the details".

Similarly so with many a scientific debate over the decades and centuries.

Australia is in the vice-like grip of a great drought, perhaps the worst for some centuries, and there's intense dicsussion of global warming and climate change. Are the "right questions" being asked about all this?

Upon this theme, at RealClimate there's an interesting recent post: Attribution of 20th Century climate change to CO2 (with lots of comments, too) ...

In public discussions there is often an emphasis on seemingly simple questions (e.g. the percentage of the current greenhouse effect associated with water vapour) that, at first sight, appear to have profound importance to the question of human effects on climate change. In the scientific community however, discussions about these 'simple' questions are often not, and have subtleties that rarely get publicly addressed.

One such question is the percentage of 20th Century warming that can be attributed to CO2 increases. This appears straightforward, but it might be rather surprising to readers that this has neither an obvious definition, nor a precise answer. I will therefore try to explain why.

For a range of findings, opinions and views see also:

• Climate change (Wikipedia)
• Forcings and Chaos in Global Climate Change
• Observational Estimates of Radiative Forcing due to Land Use Change in Southwest Australia
• Climate and Chemistry: forcings, feedbacks and phasings in the Earth System (CACHE)
• World Climate Report: Climate Forcings
  Global average temperature change projected from 16 different climate models for the 21st century if atmospheric CO2 levels are held constant at the year 2000 levels.
• Climate forcings in the Industrial era
• The Impossibility of Prediction - in which Michael Crichton, author of Jurassic Park, makes some very interesting points/claims!

D'où venons-nous? Que sommes-nous? Où allons-nous?

I just came across again some references to Paul Gaugin's 1897-1898 work "D'ou venons nous? Que sommes nous? D'ou allons nous?" (Where do we come from? What are we? Where are we going?) which is held at the Museum of Fine Arts, Boston.



I haven't made many posts to this particular blog, but that doesn't mean I haven't been musing about Basic Questions. It's just that I've been busy with my other blogs, web site, software development, and so on.

I'm about half way through Bill Bryson's A Short History of Nearly Everything and that's certainly got my grey matter working! I suppose that you could call it a superlatiave travel guide to the universe. Very nice work, Bill: most enlightening, in your usual fashion, and quite scary in places.

Size of Our World

Only the occasional entry in this blog (one of several hosted here at Blogger.com). Oh well, with apparently arounf 100,000 new blogs per day maybe nobody noticed my severe case of bloggus infreqentius.

This topic -- Basic Questions -- is pretty well covered by others, but I just came across the following and couldn't resist adding a new post here of a set of simple images that quite effectively get their message across:

The Size Of Our World

The following video gives an entirely different perspective on it all, though:

Earth has got a nasty case of the Humans

At the Edge

Although I've visited the following web site briefly in the past (a couple of years ago) I didn't pay too much attention to it back then. But now I've decided that it needs much closer attention from me in my newly-launched resolve to search for the "meaning of lfe, and all that".

It's the Edge Foundation and its mandate is "to promote inquiry into and discussion of intellectual, philosophical, artistic, and literary issues, as well as to work for the intellectual and social achievement of society."

It has an interesting section title "The Third Culture" but what whets my appetite more (in relation to this particular blog of mine) is its World Question Center so it will be indeed interesting for me to examine there all the questions that others have raised previously!

Stretchy, stringy questions

When relating a story or giving a presentation, did you ever "get ahead of yourself" the saying goes? Well, that may be the closest you ever get to to time travel! But the topic of time travel is fascinating -- as are related realms of physics -- and certainly puts more mundane earthbound happenings into perspective.

Here are a few sites with some VERY nice multimedia demonstrations and explanations of this sort of thing:

• Einstein Light - multimedia modules that present the main ideas of relativity, with background info about mechanics and Galilean relativity; electricity, magnetism and relativity (Maxwell); the principle of Special Relativity; relativistic mechanics leads to E = mc² ; how relativity implies time dilation, and more.
• The Elegant Universe - a fascinating and thought-provoking journey through the mysteries of space, time, and matter. Brian Greene's excellent 3-hour visual feast, with outstanding graphical animations explaining string theory (alias "the theory of everything").
  
• Superstring Theory >> Cosmology >> Take a trip through the Big Bang >> Black Holes

You'll find some more links like this, towards the bottom of the page at http://asiapac.com.au/Links/Sciences.htm ... or its mirror/backup USA site http://notestracker.com/Links/Sciences.htm

I really like the explanations given by physicist Joseph Wolfe of the University of New South Wales (in Australia) at the Einstein's Light website. For example, at www.phys.unsw.edu.au/einsteinlight/jw/module4_time_dilation.htm (in the section called Is time dilation true? How big are the effects?) there's this interesting example:

"Some particles striking the Earth's upper atmosphere have energies that exceed 2*1020 eV. If such particles are protons (with mass of about 1 GeV), their speeds would be 0.999 999 999 999 999 999 999 995 c. For them, g is 1011. Now the age of the universe is about 13 billion years for us, but for such particles, the age of the universe would be about (13 billion years/1011), ie about a month. Such a particle could cross the visible universe in a matter of months (their time)."

You'll have to read the rest of the article to see this in context, but it's a sobering thought all the same.

Les aventures de B & G en Amérique

I'm very relieved to know that I'm not the only one with basic questions!

Géraldine et Bertrand Le Roy apparently have a few of their own too. Here are some pourqois from their blog Les aventures de B & G en Amérique ...

• La théorie de la gravitation quantique n'existe pas
• Le ciel au bout des doigts
• Où est le nombril du monde?
• Pour la remise en question de l'évaluation par les pairs dans la recherche scientifique
• Pourquoi les miroirs inversent-ils la droite et la gauche?
• Que se passe-t-il quand on entre dans un trou noir?
• Plus vite que la lumière?
• La flèche du temps et la causalité

How wide is the Universe?

Is the universe bound to be twice as wide across, measured in light year units, as it is old (measured in years)?

The universe is reckoned to be some 13 billion years old. Does it follow that it must be some 26 billion light years across?

(This would presumably be a result of spreading out in all directions at the same speed following the "Big Bang" ... See some musings about my state of growing ignorance in this posting at my other blog: Blissfully getting to know less about everything )

NOTE: see an update to this post at:

How Wide is the Universe? - revisited

What are the "basic questions" of life and the universe?

Just last month, I spent a week or so in "outback" Australia, and was a little taken aback when somebody mentioned that the town's water supply was not fluoridated.

This -- and several recent interesting TV programs about ice ages, global warming, nuclear energy and so on -- set me thinking about scientific controversies and the "big questions" of life, the universe, and everything else.

A few decades ago there was an extremely vigorous debate in Australia about the pros and cons of fluoridating our water supplies. In the capital cities at least, fluoridation nowadays is a fait accompli and rarely if ever rates a mention. In the aftermath of the December 2004 Asian tsunami, I saw a news report in which an Australian forensic dentist sent to Thailand explained how it was easy to tell the age of an Australian victim via dental evidence: the younger victims who grew up post-fluoridation had excellent teeth, while the older (pre-fluoridation) victims had rows of fillings. (It wouldn't surpsise me if the fluoridation debate is raging right now somewhere outside Australia, that's the way things go.)

That old debate about water fluoridation is but a minor example of the sorts of debate that come and go over time. Some of these debates are of more global importance, in a variety of fields affecting us all as global citizens. Some of them rage fiercely, others are conducted in a more sedate fashion. Some questions are of immeditate interest and significance, others are much more "long term".

Here are a few such areas:

• Evolution, versus "creationism" and "Intelligent Design"? Religion versus science?
• How can past events (last week, last year, last century, last milennium, in prehistory) be accurately analyzed and reconstructed?
• Renewable energy, versus carbon-based and nuclear fuels?
• Global warming, or not? Will there soon be a sudden ice age?
• Is the earth flat? Probably not! ... But can the speed of light be exceeded? Can time go backwards? Are there multiple time-space dimensions, with multiple editions of you and me?

I am interested in hearing your considered views (without too many biases, prejudices or rantings) about WHAT are the basic questions that need to be raised in order to resolve such matters?

Please focus only on HOW the questions can be answered. Or even, if they can be. Scientifically? Rationally? By tossing dice? Via black magic, abstract logic, philosophical reasoning? How indeed?

Be sure to omit voluminous details! Link to your own blog or web site if you wish to direct readers to such details.

Finally, to put a different perspective on it, I used to be an avid reader of the Biggles books -- the "flying adventures of Biggles" --- written by Captain W.E. Johns around sixty years ago.

I vividly remember how one of them, Spitfire Parade, had as its frontispiece BIGGLES' PHILOSOPHY which went as follows:

When you are flying, everything is all right or it is not all right. If it is all right there is no need to worry. If it is not all right one of two things will happen. Either you will crash or you will not crash. If you do not crash there is no need to worry. If you do crash one of two things is certain. Either you will be injured or you will not be injured. If you are not injured there is no need to worry. If you are injured one of two things is certain. Either you will recover or you will not recover. If you recover there is no need to worry. If you don't recover you can't worry.

Perhaps Biggles' dialectical approach is the way to go!

A book that I read quite a few years go adopted more or less such an approach: The General Science of Nature, by Vincent Edward Smith (The Bruce Publishing Company, Milwaukee, 1958). Are the methods of Aristotle and Aquinas still applicable in modern debates (see http://www.morec.com/natural.htm for more)?

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Hey, guess what? Only a few hours after starting off this new blog, I happened across the following Web site: ... Ask Philosophers - "You ask, Philosophers answer"

OVER TO YOU for your contributions and feedback ...