Brian Greene - Why Is Our Universe Fined-Tuned for Life?

Have you noticed that wherever Brian Greene goes, computer animations go with him? Well, this TEDTalk presentation is no exception :) I'm starting to wonder whether this might be the physicist equivalent of a comfort blanket...

In any case, and as you may expect if you're familiar with him, he lays down the case for string theory, and explains some of the fascinating implications if string theory and the cosmological theory of inflation were true. Even as mere hypothetical possibilities, these ideas merit our attention.

What I do have a major problem with, however, is his "explanation" for why our universe is fine-tuned for life. It's a version of the anthropic principle that is either completely backwards or completely question-begging (circular)... or both... I'll let you be the judge:

The analogy with our distance to the sun doesn't quite work because, despite his explicit claim to the contrary, it's asking one question but answering another. Our distance to the sun doesn't explain why Earth is  x-number of miles away from the sun (see what I mean by circular?). It doesn't tell us anything about astronomy or physics.

What it explains is why we live on Earth and get to ask that question, but it tells us nothing about the conditions that led to our planet being where it is... Similarly, the fact that we happen to inhabit the particular kind of universe that contains the conditions that allow for life-forms such as ours tells us nothing about why this particular universe happens to have those particular features.

In other words, you can't answer the question of why is our universe fine-tuned for life by answering that it's because our universe is fine-tuned for life... or am I missing something here?

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Standing on the Shoulders of Giants

This famous phrase, made famous by Sir Isaac Newton, and celebrated ever since, may have been a public attempt at modesty and historical gratitude that was sure to endear him to, and inspire, subsequent generations of natural philosophers, but it may also have been a little bit of an underhanded insult to Robert Hooke, just the kind of thing Newton would do when his gigantic and fragile ego was wounded if anyone dared to question some of his ideas...

Still, the phrase has taken on a life of its own, and it is now used to describe the incredible scientific and technological progress that has taken humanity to the unique position of being able to question its own origin and place in the universe, and to actually start to answer those questions, change its environment, make its dreams more ambitious and then make those dreams come true. The following captivating video is a beautiful celebration of the cumulative knowledge and insight we've gained about ourselves and the universe in only a few centuries, and the amazing feats we've accomplished as a result, by standing on the shoulders of giants:

Hope you're inspired!

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To Infinity and Beyond

Apparently the title of this documentary also has something to do with Toy Story? Well, I haven't seen that movie, but I can tell you what this documentary is about... Infinity. The most obvious way to start thinking about infinity is through numbers: take any number, and you'll soon realize that there is no such thing as the biggest number because you can always add 1. No, a googol won't do it, nor even a googolplex or Graham's number. Yes, these numbers contain more zeros than there are atoms in the observable universe, but they still fall short, infinitely short, in fact, of infinity.

But the strangeness doesn't end there because infinity may not only be a mathematical conceptual idea: infinity raises all kinds of interesting scientific and philosophical questions and paradoxes (what Immanuel Kant called antinomies of reason) about the physical universe that even modern cosmology doesn't quite know what to do with: is space infinite? If not, what's beyond its edge? Infinite empty space? What about time? If it is, and the amount of matter in the universe is finite, then everything that could logically happen has happened, and will continue to happen, an infinite number of times... And hey, are there an infinite amount of universes? And as you'll see in this fascinating documentary, this is just the beginning of the weirdness:

For a fascinating treatment of the problems of infinity, check out the documentary Dangerous Knowledge.

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The Fabric of the Cosmos - The Illusion of Time

In the first episode of the Fabric of the Cosmos series, we learned a little bit about the weirdness of space, so hopefully that massaged your brain enough for something even weirder: time.

Philosophers and scientists have been trying to understand what time is since antiquity, and one thing that they have found is that it's incredibly difficult to say anything about time without already presupposing it in some sort of viciously circular argument. Nevertheless, curiosity drives us to ask questions that we then have to test by conceptual analysis and by empirical means, and we often find out that these come in conflict with each other in ways that elude simple solutions.

There are philosophical accounts of time (and I'll provide a short introduction soon), as well as scientific accounts, most of which are based to various extents on some of the incredible insights to come out of Einstein's theories of special and general relativity.

So fasten your seat-belts as Brian Greene takes us on a tour to understand some of the deepest of mysteries: What is time? Does the past exist? Does the future? Can we change the future? Can we travel back in time? If so, can we change the course of history? And hey, if you can go back in time and meet your former self, which one is really you? That last one is more of a philosophical question, just to show you how badass we are :)

If your head isn't spinning by now, then you might want to get yourself checked into a hospital :)

And if you want to watch the original from NOVA, here it is:

Watch The Fabric of the Cosmos: The Illusion of Time on PBS. See more from NOVA.

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Questions No One Knows the Answers to

Many parents tend to grow increasingly frustrated when their children suddenly become question shotguns, going from one question to another, faster than the parents can dish out answers. Comedian Louis C K can at least turn these episodes into hilarious material for his stand-up. Things, of course, tend to turn particularly frustrating when the shotgun turns into a fully automatic machine gun full of 'why.' I wonder if the frustration is not really about the children but about the parents' sudden recognition of the limits of their own understanding...

In any case, if you happen to find yourself surrounded by a bunch of pre-schoolers outflanking you with their innocent inquiries, maybe you can take advantage of their curiosity and teach them a little bit not only about the things we know (or even about the things we do not yet know), but about how we might be able to start thinking about these questions, and how the very fact of our ignorance can become the platform to future discovery, as the following animation from the TED people shows

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The Fabric of the Cosmos - What Is Space?

That's probably not the first question that comes to mind for most people when they wake up in the morning, but it is definitely one that has kept some of the greatest minds of all time awake at night. What exactly is space? Is it a substance? Is it merely a relationship between objects? Whatever it is, is it static or dynamic, absolute or relative, immanent or transcendent? If there no physical objects in the universe, would empty space still exist, or is that an incoherent question, like asking what happened before the beginning of time? Join Brian Greene in a fascinating (if gimmicky) exploration of one of the most fundamental scientific and philosophical questions in this first episode of The Fabric of the Cosmos:

And in case the youtube video stops working at some point, here's the original from NOVA:

Watch The Fabric of the Cosmos: What Is Space? on PBS. See more from NOVA.

For more related videos, check out the Elegant Universe Tag.

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Faster Than the Speed of Light?

Some months ago, news broke indicating that scientific measurements in Italy had determined that some neutrinos could travel faster than the speed of light. The media jumped on the hype bandwagon and declared the "death of Einstein's theory of relativity." Physicists (aka, the experts on these questions) were skeptical because ALL previous experimental and observational data, including neutrinos and light traveling from super nova explosions really really far away and reaching Earth at exactly the same time, confirmed Einstein's predictions, so they concluded there must have been some error in the measurement, the analysis, the equipment, etc. on which the Italians relied. Of course, there were also cultural reasons for doubt: as Sergio Bertolucci, research director at CERN indicated, "I have difficulty to believe it, because nothing in Italy arrives ahead of time." :)

News are starting to pop up everywhere now that there was indeed a glitch in the equipment. Still, whatever the real answer turns out to be, and since everyone seems to be paying attention to the story, this presents a great opportunity to learn some fundamental lessons not only about relativity and other ground-breaking research in theoretical physics and cosmology, but how science itself works and makes the tremendous progress it does, so let's watch this delightful documentary narrated by Professor Marcus du Sautoy:

Sometimes I do wonder whether these physicists are insane in the mem-brane :)

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Everything and Nothing - Nothing

The idea of a vacuum, nothingness or the void has troubled Western thinkers since at least the time of Parmenides. The problem started as a logical puzzle: how could nothingness, something non-existent by definition, be?

This rejection of the very possibility of nothingness is captured in the famous medieval dictum ex nihilo nihil fit (nothing comes from nothing), used among other things to prove the existence of God, since the universe, it was thought, could not have sprung from nothing all on its own (never mind where God came from). You probably won't find it surprising that it would be David Hume who would first challenge this notion when he declared that, logically speaking at least, anything could come from anything :)

But the problem isn't merely a logical one: it's also empirical. Since at least the time of Aristotle, attempts to create a vacuum consistently failed for almost two thousand years; that is, until Evangelista Torricelli serendipitously managed to create one when he invented the barometer and proved that we live at the bottom of an invisible ocean of air.

With the creation of a vacuum, and as Professor Jim Al-Khalili shows in this fascinating documentary, scientists have slowly come to understand not only the nature of vacuums and nothingness but that the entire universe may owe its existence, literally, to nothingness... There will be some quantum weirdness here, but of the real kind...

Couldn't those fluctuations be due to something as mundane as neutrinos flying through the tanks?

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Everything and Nothing - Everything

You may find this hard to believe, but we've known about the true size of the universe for only about 100 years. When Copernicus proposed his revolutionary heliocentric model, for instance, he still believed in the existence of a perfect celestial sphere where all the stars revolved around the sun in a perfect circle. That belief would be slowly chipped away with the observation of a Super-Nova explosion in 1572.

It wasn't until the 1920's when Edwin Hubble, thanks to a brilliant idea proposed by Henrietta Swan Leavitt, was able to measure the distance to a Cepheid variable in what was suspected to be either a weird part of the Milky Way, or an altogether different galaxy. The measurements made it clear that the universe was orders of magnitude larger than we had suspected.

Could it, in fact, be infinite? Does space go on forever? Or does it have to have an edge? If it has an edge, what's on the other side? More universe? And if it's infinite, and there are an infinite number of stars, why isn't the night sky as bright as it is during the day?

In the following documentary, Professor Jim Al-Khalili traces the history and the science behind these and other similarly fascinating questions that scientists, especially with the help of brilliant minds like Gauss, Reimann and Einstein, are just beginning to solve.

I would have thought that a finite amount of stars would solve the problem much more easily, but maybe Professor Al-Khalili hasn't heard of Ockham's Razor? :)

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Brian Cox - The Forces of Nature

Philosophically, the idea of forces is kind of shady. While we don't want to outright deny the notion, we also don't want to ignore the danger of possibly believing in what could turn out to be the scientific equivalent of leprechauns. The first problem is that 'forces' are not things experienced directly; rather, they are inferences produced on the basis of other experiences, and as inferences, these could turn out to be misinterpretations of what might be entirely different phenomena.

Take the case of gravity. Before Einstein, it was believed to be a force in the classical sense, but post-Einstein, our understanding is that gravity is not so much a force as an illusion of a force produced by the curvature of space-time.

So, while Brian Cox introduces forces as the 'agents of change" of the universe in the following video clip (and does a nice job of explaining the basic history behind their discovery, understanding an unification), one should still be aware that he's treading in conceptually dangerous territory, and that just like philosophy devoid of science is likely to get itself in trouble, science would be equally foolish to eschew the importance of philosophical analysis. Let's make love, not war :)

I'm kind of curious... whatever dark energy turns out to be, is it possible it might provide evidence of a hitherto unknown (and possibly even unsuspected) new force?

And if you want a fuller treatment of these ideas, check out the Elegant Universe tag, and especially the documentary Atoms, with Jim Al-Khalili.
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Horizon - What is Reality?

Ancient Greek philosophers like Parmenides, Zeno and Plato stumbled upon a radical discovery: the distinction between appearance and reality. If we are to ask the question of what reality is (and how we can know this), our best bet at finding some sort of answer would require that we delve deeply into science, mathematics and philosophy.

The following documentary explores some of the questions that are currently at the border between scientific inquiry and philosophical speculation: What are the basic constituents of the universe? How does quantum mechanics make sense? What's up with the double-slit experiment? Is mathematics the language in which the laws of the physical universe are written, or is the universe actually part of a mathematical structure? Do we live in a multi-dimensional universe, or are we simply the holographic projection of information forever trapped in the event horizon of some supermassive black hole? And why can't a guy get a date on a Saturday night? :)

I think the pony tail might help explain the mystery of the last question :)

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