h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

http://www.bbc.co.uk/h2g2/guide/A527573

Hi,

this is my first attempt to make an entry to the Guide. I hope I'm doing it the right way; if not; please notify me.

I wrote a short article concerning the possible and rather strange things travelling at the speed of light does to humanoid senses. Offcourse there will happen a lot more than the things mentioned in the entry, but I think this is a pretty good start and this will get some people starting to think about the possible implications.

I hope you will have fun reading the article. And when you're done reading, I hope you can tell me if I'm on the right track of making a suitable entry to the Guide.

Have fun!

Nussie

Good idea, there ought to be an entry on this subject, but theres quite a lot of stuff that needs adding. There really needs to be a treatment of this talking about relativity, maybe describing what you'd see as you approach light speed (relativistic distortions etc). Also should mention Einstein's thought experiment (essentially the same as yours - what would it look like, sitting on a beam of light?), and the fact that a human actually travelling at light speed is impossible (as far as we know, with current physics) due to requiring infinite energy to get you there.

Maybe an analogy with what happens (what you hear) when you travel at the speed of sound would fit nicely (though wouldn't give a totally accurate picture of travelling at light speed, I'm not sure exactly what the differences would be - best talk to a physicist)

BTW, just on a style point, there shouldn't be any use of the words 'I' or 'me' in an entry - its usually pretty easy to rephrase things a different way.

Henry,

thank you for the advice! I'll try to make some slight adjustments to my entry right away.

I enjoyed reading this article Nussie. I know me and a mate of mine spent a bit of a boring physics lecture debating on what would happen if you travelled faster than the speed of light ('c').

1. Because of Newton (what a strange bloke he was) it is kinda agreed that you'd need infinite energy to travel at the speed of light, and with infinite energy you have infinite mass. So basically you'd be a big fat fast moving blob. You might have to put some bits about the equations he uses in this, to explain it.

2. We also looked at 'looking at a clock' whilst travelling backwards at the speed of light. As you nearly reach 'c' the clock would look like it was going slower and slower. It would stop at 'c' therefore looking as if time had stopped. Unfortunalely I don't think you could go faster and still see the clock as the light wouldn't reach your eye.

I can't really remember much else, this being 2 years ago, but I could get my physics notes if you wanted to get a bit more technical. This might not be needed in the article, if you want it to be understood by most readers, who haven't done an A-level in Physics. Keep up the good work (not meaning to sound like my mum).

SallyM

If you want to do an article about "What you'd see close to light speed", that's fine, but an article about what you'd see at light speed is just pure fiction. It is not possible to reach light speed, that is the whole point of the Special Theory of Relativity. It is not some barrier like the Sound Barrier that you have to work hard to get past. No matter how hard you work, you will not ever reach light speed, never mind get faster than it.

As far as I remember, close to light speed you can get some really crazy effects, so it would be worth an article, if you're up to doing the research.

Hello,

Actually, I seem to recall that even if you're moving at the speed of light, you'll see light relative to you moving at the speed of light. Basically, light's always moving at the speed of light to you, no matter how fast you're going towards or away from it. The only real effect is that it's wavelength might shift (red away, blue towards). So you'd still get light from your clock (even if you were looking backwards), but you'd also be an blob with infinite mass (unless you were a photon). And time would slow down for you, but seem longer for observers.

It's all a bit confusing, but I think the bit about the shadows is incorrect. The best explanation I've seen so far is the first chapter of the "Elegant Universe" by Brian Greene. Also, string theory has some interesting things to say about the big bang, but I won't get into it.

Yours,
Jake

This seems to need a major rewrite.
First, it says that it is about what happens to you andyour shadow at the speed of light, but treats them seperately. they should be tied together like "this is what you would see, and this is what would happen to your shadow".
The points about what you see seem pretty irelevent, unless you add why you would or wouldn't see them.
You would see and experience things normally, anyway, as particle physics has proved that after you reach 0.7c you start to get massive amounts of time dilation. you might get colour shifting though.
physics says that you can't reach light speed, due to the increasing mas once above 0.7c, which is derived from einstein, not newton.
Physics is at least partially WRONG. Physics says that nothing can travel faster than light, but at CERN they proved that the colapse of the wave form with dirac pairs travels INFINITELY fast. This probably won't effect the ability to travel, but does show that the physics surrounding light speed is rather incomplete, as does the fact that relativity and quantum theory re mutually incompatable.

AFAIK, Relativity says that information cannot travel faster than the speed of light, and as it happens, you cannot send any information with collapsing entangled pairs.

Yes you can. by forcing them to colapse when you want them to, you send the information faster than light that the time is NOW. In some situations this could be useful.

Actually, if I understand it correctly (I'm not a physicist however), you're not sending real information in that case. Is this the experiment with two linked photons sent in opposite directions? I recall in that one that examining one of them (i think for polarity), immediately collapsed the possibilities of the other one to be the same. This "spooky action at a distance" was seen as faster than light communication at first (between the two photons), but I'm unclear how it could be used to send actual information.

Basically, on the receiving side, the only way you might be able to tell whether the other end has collapsed the waveform is to look at the one on your end. This immediately collapses your waveform (and theirs), basically not allowing you to really know when they collapsed theirs. The problem with quantum physics is that it is impossible to observe phenomena without interfering with them. You wouldn't be able to receive some notification that they've collapsed the waveform without such observation I think.

Yours,
Jake

Hello,

Some outside refs that might be useful. Basically, there is some controversy about FTL communication these days, but under conventional physics it's not possible and nobody has been able to conclusively show otherwise it seems. Like conservation of matter, it remains a bit of an axiom (largely because of the causality issues involved). Still, it may happen (it would be cool if it were possible):

[url removed by moderator]
[url removed by moderator]

These are totally non-commercial, so please don't moderate them out.

Yours,
Jake

You need to put the links on your home page, then add a link to the links... It's a pain, but they seem to like these mind games.

Hello,

Yeah, I could do that, but I really hate that approach because it decouples some of the comments from the discussion, thus giving us the same disconnectedness and unreliability of the WWW in general. Luckily, it looks like that policy is under review, so we might get some progress on that in the future.

Yours,
Jake

Nussie appears to be AWOL, and I happen to agree that this entry does need a little bit of work doing on it. It's difficult to tell without Nussie saying what he was trying to achieve, but while he makes this decision, I suspect this thread should be moved to the Writing Workshop.

What does everyone think?

If Nussie is AWOL, then yes, this should go to the Writers' Workshop. Someone who wanted to do a tremendous amount of reseach on theoretical physics could then give it a go, from the angle 'What It Would Seem Like, from the Anthropomorphised Point of View of a Photon, Travelling at Lightspeed' or somesuch nonsense. I actually thought the premise a very fun one, even if it is impossible.

Arpeggio, for LeKZ

I have to admit that I also think this one is Writing Workshop bound. Anyone else?


Mikey

I second, it needs a LOT of rethinking and rewriting.

I just happened to think:
If I travel at the speed of sound(or more) there's no problem to hear really, actually, you hear what's in fron of you, but not what's in the back of you, and you hear it condensed.

I belive with light (if you wave all the problems with pushing a mass at that speed) it'll be brightr and mixed together visions in the front and blackness in the back.

Also, the inside of the vessal should be normal, because it's relative speed will be zero to the watcher.


Dancer

Editorial Note: This conversation has been moved from 'Peer Review' to 'The h2g2 Writing Workshop'.

Cool, now that were in the writing workshop we can get started and get this entry back in better shape.

I think main things to do are:

1. Make th entry more factual. Less based on speculations.
2. Give some "meat" around the entry about the actual theoretical impossibility of things and how the entry is based on the fact that we completely ignore the problems of pushing matter in the speed of light. This can be done as Mach one was though impossible to reach not too long ago.

So, are we up to it?


Dancer

I like it so far, but you should consider adding some more questions and possible answers.

Also, you should avoid using first person when writing for The Guide. (I, we, etc.) Also, you should think about who's going to be reading your entry to The Guide (is everyone a native English speaker from Earth?).

Look for information that is already in The Guide and link there. Also, consider internet sites that have the most current scientific understanding of the speed of light and its possible effects.

Keep going!

Tony