I Don't Believe in Gravity...

In a previous post, I suggested the Big Bang may not have been the almighty universe-spawner it’s made out to be (if the universe did expand from a single point, wouldn’t it have done so in a uniform fashion, rather than bits of it clustering together to form galaxies and nebulae and whatnot?).  For the latest episode of Bollocks My Scientifically Illiterate Brain Comes Up With During Its Downtime, I’m going to attempt to explain why I don’t believe in gravity… Buckle up, kids!

As I said previously, such nonsense is not born from - or backed by - any cold, hard scientific knowledge; it is merely how I interpret what little I’ve picked up from what little I’ve read and watched on the subject.  This particular theory spawned from an interview Prof. Brian Cox gave with Robert Lewellyn, when he mentioned massless particles are always moving at the speed of light.  Not from any outside influence (unless one considers the (or a...) Big Bang the initial ‘push’); it’s simply what they do (28m22s):

(the whole thing’s worth watching)

One thing that has long bothered me in physics is how light appears to be affected by gravity.  Light bends around planets, supposedly diverted off course by the planet’s gravitational pull, but if the strength of gravitational attraction is determined by mass, how can something massless be affected by it at all?

It depends on how you view gravity.  The idea of gravity as an attracting force between objects of mass was initially (supposedly) put forward by Newton, and was the established view for centuries.  Then Einstein came along:



So the fact that light is always moving means it isn’t attracted to the object at all; it just follows the curve of the object’s impression in the fabric of space-time.

This also helps answer another query: A black-hole is an object of such dense mass that even light can’t escape its ‘pull’.  However, a black-hole is (at least initially) no more massive than the star that formed it - it’s simply more compact - so why is its gravitational pull apparently so much stronger, to the point that even light can’t escape?  Stars come in a range of sizes, from those smaller than our own sun, to those that could swallow our entire solar system as an appetizer.  And yet, no matter how big, all stars emit light, while, no matter how small, all black-holes swallow it.

Going back to the demonstration above, if you were to compact the weight in the centre of the sheet to a fraction of the size, it would sink just as deeply into the fabric (as it’s no lighter or heavier than it was), but the diameter of its impression would be smaller, and so its sides steeper.  In terms of a black-hole, its mass is packed so tightly that the ‘sides’ of its impression become sheer.  Therefore, regardless of how massive (or not) the core of the black-hole is, the shape of its impression on space-time causes anything caught in its ‘pull’ - no matter the speed it’s travelling, or its angle of approach - to be diverted directly to its centre.

But what about objects of mass themselves?  They certainly appear to be attracted to each other, but are they really?  What if, like light, everything in the universe is moving at its own pace, relative to its mass?

Well, everything is.  Supermassive black-holes drift through the cosmos, orbited by stars, that are orbited by planets, that are orbited by satellites; the smaller objects moving at the speed of the larger, plus their own orbiting speed.

So, if everything from light to black-holes is moving at its own pace, and its path through the universe is only interrupted when it hits the space-time impression of another object, then where does gravity come into it?

It’s like a shadow.  A shadow isn’t a tangible thing; it’s simply the effect of blocked light.  It seems to me that gravity isn’t an attracting force at all; it merely describes an object’s interaction with another object’s space-time impression.

In the next episode: what if light is space-time?

A More Positive Outlook

I originally scribbled this down a few months back, while pondering the sorry state we're currently in as a species.  I often find it difficult to remain optimistic in our present global climate of ignorance, greed and distrust, but every now and then, a light shines through and I think, Y'know, we might not be so buggered, after all.

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The Earth formed four and a half billion years ago.  For more than half of its existence, it was bereft of life, but as it cooled, circumstances - temperature; atmosphere; chemical compounds; water - were just right for life to form.  The formation of that life immediately changed the circumstances - using up resources; expelling different compounds - the new circumstances gave rise to new life, which resulted in new circumstances...and so on.

By the time the Earth was four billion years old, the ever-changing combination of life and environment came together to cause the Cambrian explosion: a sudden rush of evolution that gave rise to more complex and diverse lifeforms, which spent the next hundred million years or so growing and expanding and dealing with an ice-age, until the Devonian period of fish, plant life and the earliest land animals.  That lot lasted a good two-hundred million years, before a dramatic climate shift, and second ice-age, all but wiped the slate clean and paved the way for the dinosaurs.

Things settled down again for the next hundred and fifty million years-ish, with some of the dinosaurs holding on to their reptilian roots, while others took on more avian attributes, until a meteorite hit and the whole thing required a rethink.  The larger animals couldn’t survive.  The rest either went to ground or took to the air.  Some primates, however, simply got smarter.

Over the next sixty-five million years, the primates’ intelligence grew - thinking their way to survival - and a certain branch learned to not only adapt to their environment, but to adapt their environment to them.  Tools; shelters; clothing.  They learned to grow crops; they learned to hunt rather than simply relying on the land.

A mere two hundred millennia ago, we finally emerged.  A mere two hundred thousand years, after more than two billion of evolution.

In a time when our species is so at odds with itself, I’m comforted by the fact we’re still so young.  Our capacity to learn has afforded us a great advantage over previous species: where evolution once took thousands of generations and millions of years, our thirst  for understanding, and powers of empathy and self-awareness accelerated our own.  Physically, little has changed over the last two hundred thousand years, but our ever-expanding intellect has taken us from seeing the sun as a deity to understanding it is in fact a big ball of burning gas; from thinking of the Earth as a flat plain several thousand years old to (most of us) knowing it’s a four and half billion year-old sphere; from being locked firmly to the ground to crossing the oceans by air and sea, and even walking on the moon.

While in recent millennia, we have stumbled - morality was replaced with religion; empathy with a distrust of people beyond our artificial borders; our thirst for knowledge with the desired comfort of ignorance - these things are fleeting and cannot sustain themselves.  They weaken us as a species and hold us back, but in the end, those clinging to these dying attitudes will themselves die out; left behind while the rest of us come together to seek out the next unreachable horizon...and reach for it.

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The latest inspiration for this somewhat-rosier-than-usual outlook comes from China's drive to be a significant global player in the world of science.

While chasing a dominant footing, there appears to be a prevailing attitude of global cooperation in China's scientific community: an acceptance that, without that cooperation, any advancement will only get so far, and will be soon outstripped.

On the world stage, science is tragically unique - or, at least, in very limited company - in this regard.  While national leaders squabble like children over who owns what, who has the biggest and best toys, and who's omnipotent ghost could deck anyone else's omnipotent ghost, scientists the world over are united in their goal to advance the knowledge and understanding of everyone.  Whether it be the various teams at CERN or on the International Space Station, there's an acknowledgement that the best thing for everyone is to work together.

And if even a regressive, constrictive and skittish government like China's can see the benefit of international cooperation, then there's yet hope for the rest.