UFO Proliferation

[Tingles]

David Icke.....

Well he reckons that over the next few years there will be a 'percieved' threat from 'outside' - which will speed up the World Government etc...

All these sightings are of course invented by 'The Elite'.

Sorry I missed the posts today - had some work to do!!!!



T

[Marina]

Thanks for explaining it, but it does sound definitely in the league of wacky ideas.

Ok let’s look at the following.

Voyager 1 is currently 106.027 AU away from the Earth. It is the furthest, still functioning human-made object from our planet.

It was launched in September 5th, 1977. Call it 31 years ago.

How far, in light years has Voyagrt 1 travelled in that time ?
0.0016765 of a light year.

So, 31 years to travel 0.0016765 of a light year.

Yet, according to time dilation, perhaps only x days, weeks or even months have passed “on board” the probe ?

The Voyager spacecraft do a fair speed by everyday standards, something like 35,000 MPH. But that's sluggish compared to the speed of light, i.e. about 9.7 miles per second versus light which is 186,000 miles per second.

So the Voyagers have a speed v roughly equal 0.00005 * c, or in other words v/c = 0.00005

However, time dilation involves a factor of 1 / SQRT(1 - (v/c)^2). So when v/c is tiny (as it is in every day life and even, as seen above, for the Voyagers then (v/c)^2 is far tinier still i.e. 0.0000000025 for the Voyagers.

This means 1 - (v/c)^2 and therefore the factor is as near as dammit 1, so the time dilation is insignificant (albeit not zero).

But when v/c approaches 1, for example if v = 0.99 * c then v/c is 0.99 then 1 - (v/c)^2 and its square root approaches zero. So as you accelerate to within a whisker of c the factor approaches a "divide by zero" error and in the process the time dilation factor sharply increases.

The above all relates to so-called Special Relativity, which doesn't take into account gravity. General Relativity, which does, also predicts time dilation caused by gravity differences - Time passes slower for a watch at sea level than an identical watch on top of a mountain.

In a feeble gravity field like the Earth's the effect will be miniscule, picoseconds over years. But if you were orbiting a large black hole at some distance and lowered a watch down in a bucket to just above the event horizon and pulled it up a day later (as measured by your identical watch) the other watch would have advanced maybe only an hour or two!

Takes a bit of getting used to, but it's been verified in all kinds of ways. GPS for example would be miles out if Relativity (Special and General) wasn't taken into account.

[shoes]

Use gravity wave generators to temporarily warp spacetime, sheesh.

[expat]

Relativity

Einstein himself did say that the problem with relativity was not that it was hard to understand, but that it was hard to believe.

But it was experimentally established some 90 years ago.

[TimberWolf]

...Takes a bit of getting used to, but it's been verified in all kinds of ways.

I'm wondering what things would be like if the maximum speed were 30 mph instead of 300,000 m/s. I'm beginning to suspect it would be the same as now, but I havn't finished confusing myself about it yet. For instance time dilation would come into effect at sub 1mph speeds and there would be a cost to acceleration (increased mass etc), and your partner would have aged by the time you get home if you go too fast.

[HairyArsedBloke]

Use gravity wave generators to temporarily warp spacetime, sheesh.

Yeah, kids today. Always with it can’t be done. They should do what we did when we were young: get on our bikes and figure out how to make it happen.

I'm wondering what things would be like if the maximum speed were 30 mph instead of 300,000 m/s.

Well, ignoring the fact that if it was that low then it would prohibit the existence of matter in a form to build star and planets out of ........

[RichardCranium]

Diver's got a friend... Bless!

But of course. Nurse Gladys.

[TimberWolf]

Well, ignoring the fact that if it was that low then it would prohibit the existence of matter in a form to build star and planets out of ........

This Cambridge professor doesn't seem to think so:

[An] important lesson we learn from the way that pure numbers like α define the world is what it really means for worlds to be different. The pure number we call the fine structure constant and denote by α is a combination of the electron charge, e, the speed of light, c, and Planck's constant, h. At first we might be tempted to think that a world in which the speed of light was slower would be a different world. But this would be a mistake. If c, h, and e were all changed so that the values they have in metric (or any other) units were different when we looked them up in our tables of physical constants, but the value of α remained the same, this new world would be observationally indistinguishable from our world. The only thing that counts in the definition of worlds are the values of the dimensionless constants of Nature. If all masses were doubled in value [including the Planck mass mP] you cannot tell because all the pure numbers defined by the ratios of any pair of masses are unchanged.
http://en.wikipedia.org/wiki/Variable_speed_of_light

[HairyArsedBloke]

This Cambridge professor doesn't seem to think so:

...If c, h, and e were all changed so that the values they have in metric (or any other) units were different when we looked them up in our tables of physical constants, but the value of α remained the same

Like he says, so long as you change Planck's constant and the charge on the electron too then everything would be the same, but that wasn't what was speculated.

Anyway, I've often wondered why c is so low. It puts a limit on technological development and as noted quarantines the various star systems off from each other. Maybe that is the plan. Perhaps we should have a word with the great maker to get it changed?

[ace00]

The Fermi Theory is all well and good, saying "if there are so many lifeforms, why are they not here ?", but it completely ignores the fact that to travel to us in a meaningful timescale is beyond the laws of physics.

Fermi Paradox specifies sub-light speed travel. It is the time-scales involved that raise the paradox.
Use a mind-game. Imagine the human race in 100 million years time. Would we still be pottering about on planet Earth messing with computers and stuff? No. We have I guess 100 stars within 20 light years, most with planetary systems. They'd be colonised, at least by mining colonies. And the 10,000 stars within 20 light years of those? Them too. Imagine our energy / signal output, it would be hard to miss even from 1000 light years away.
So the time has been there but we see nothing. And personally, if I try to visualise the human race in 100m yrs, I don't see it happening. In fact I'm stretching to see us around in 200!