Oolite Bulletins

Drew wrote:

Of course, what we really need is a technology that can give a sustained 1g acceleration without stupid amounts of reaction mass. That would get us to Alpha Centauri in a little over a year...

A year to reach a star four light years away? Really? What's the noise? My word I do believe it's Albert, spinning in his grave!

DaddyHoggy wrote:

Drew wrote:

Of course, what we really need is a technology that can give a sustained 1g acceleration without stupid amounts of reaction mass. That would get us to Alpha Centauri in a little over a year...

A year to reach a star four light years away? Really? What's the noise? My word I do believe it's Albert, spinning in his grave!

Oops... meant decade I think!

Cheers,

Drew.

For lots more stuff about why we're not going anywhere fun, anytime soon (barring any radical developments in physics), see the fascinating/depressing Project Rho.

Fabulous website Disembodied!

But depressing.

Cheers,

Drew.

Could always fly the shuttle while you wait (and see how dull (and hard) real spaceships are to "fly")

http://www.gieson.com/Library/projects/games/shuttle/

Who recalls the scene in SW2 - Attack of the Clones, where Count DooKu escapes Geonosis in this tiny craft and once in space deploys solar sails to journey back to Coruscant. Often wondered about the distance involved. Unless for the sake of brevity, the journey didn't take much time at all.

Isn't there a DS9 episode where Sisko builds the equivalent of a wooden boat with Solar Sails that gets caught up in some eddy current that accelerates him up to warp speed all the way to Cardasia?

DaddyHoggy wrote:

Isn't there a DS9 episode where Sisko builds the equivalent of a wooden boat with Solar Sails that gets caught up in some eddy current that accelerates him up to warp speed all the way to Cardasia?

Yep. It didn’t look very efficient to me.

Wow, talk about high-tech, low-tech style.

Interesting thing about top speed, in space or otherwise, is that (according to Einstein) as soon as you go beyond the speed of light, you turn from matter into energy (that's part of what e=mc2 is about).

Dragonfire wrote:

(according to Einstein) as soon as you go beyond the speed of light, you turn from matter into energy (that's part of what e=mc2 is about).

[citation needed] :-)

Dragonfire wrote:

Wow, talk about high-tech, low-tech style.

Interesting thing about top speed, in space or otherwise, is that (according to Einstein) as soon as you go beyond the speed of light, you turn from matter into energy (that's part of what e=mc2 is about).

You cannot go beyond the speed of light.
If that could happen, science has drastically changed.
At least as far as I know.

The speed of light is, what in Mathematics is called, a Supremum.
It is a border that the system cannot exceed.
If you have a lowest value - like 0 degrees Kelvin - it is called Infimum.

Particles have been found on Earth that are "born" out in space - far from Earth.
Their life-span is extremely short, and even if they travel with speed of light, there is no chance that they can reach our planet.
Still they were found here - where they cannot be formed.
This was a mystery to science at first. As it at first seemed to violate the principles of Einsteins' theories.

The explanation given to me was that they believed these particles "simply" tunneled through the time-space.
They didn't exceeded lightspeed but took a "short-cut".

The name of Einsteins theory of relativity is misleading. It would better be called - The theory of constancy.
If two cars are driving to meet each other on a road - say that both of them have the velocity of 30 miles/hour.
Then their relative speed, measured from one of the cars, will be 60 miles/hour. As they are driving towards each other one simply adds their speed.
But if two photons are approaching each other with Lightspeed, then the relative speed will still be "c". They will still approach each other with c, not with 2*c as with the cars.
And the relative speed of the cars will actually be somehow smaller than in Newtons view of the world.
But the difference is too small to be measured. They simply moves too slow for a precise measuring.

If we call the velocities in the systems for v1 and v2 the Lorentz transformation gives:

v=(v1 + v2)/(1+v1*v2/c^2) that will give v= (30+30)/(1+30*30/c^2) and one can see that v will be almost 60 but slightly smaller for the cars.

In the photons case we will have: C=(c+c)/(1+c^2/c^2)=2*c/2=c

So - in the same medium (mostly vacuum when it is refered to) c is always constant.

Two things I think I remember from when I was doing physics degree and from working at RAL, was 1) Einstein left himself a sleight of hand get out of jail free card - the gist of which is - anything which, at the moment of the creation of the universe was accelerated to a speed beyond that which we now understand to be the speed of light, could still be around and still travelling at this speed. 2) When I was working on ISIS at RAL some of our neutron impacts on our targets generated some interesting particles as did some of the work we did with CERN, the fact that we detected the particles at all was the interesting thing - given their inherent instability and therefore a lifespan measured in the billionths of a second, even at a big percentage of c, they should never have made the distance between the source and the detector BUT because they were travelling at such a big percentage of c, they suffered from the same time dilation effect we would if we too were travelling at such speeds. Therefore as far as the particles were concerned they still lived for a few billionths of a second but relative to us they lived long enough to reach the detectors...

DaddyHoggy wrote:

When I was working on ISIS at RAL…

A similar, more widely known phenomenon is cosmic ray secondary muons. Without time dilation, their half-life would only be long enough to travel 660 m, but at near light speed muons generated in the uppermost atmosphere can be detected deep underground.

Ahruman wrote:

DaddyHoggy wrote:

When I was working on ISIS at RAL…

A similar, more widely known phenomenon is cosmic ray secondary muons. Without time dilation, their half-life would only be long enough to travel 660 m, but at near light speed muons generated in the uppermost atmosphere can be detected deep underground.

As ever Ahruman, I'm grateful for you, for cutting through my guff, to something easily accessible and understandable.

And proof (of sorts) that I once used to be a proper bona fide scientist - this is where I used to work: http://www.isis.stfc.ac.uk/ (wonder if any of my detectors are still working (I built detectors for HRPD and CRISP, and where PEARL lives now, used to be my Test beam for all my little experimental configurations))

DaddyHoggy wrote:

As ever … something easily accessible and understandable.

Ooh ’eck, aren’t we sarky today! :-p