Time travel

[Stevo]

Originally posted by CharlieG
Is it true about that philosophy exam at one of the unis where the question was "Why?" and the answer that got perfect marks was "Why not?"

Just a rumour, probably. Would get zero marks from me. Responding "Why not?" to "Why" is really just evading the question, not answering it.

 

[dr nick]

Originally posted by Stevo
Well, the energy of a photon is given by E = hv. Planck's constant is in units of Joules seconds, which means it is in units equivalent to momentum X distance. So E is in units of momentum X distance / time. Or momentum X velocity, which is also given by Einstein's relation E = pc.

As for solar sails, I just read an article on it recently, but can't recall the details, unfortunately. But I think most of it was in response to those claiming that solar sails violated thermodynamics.

Solar sails are being developed by NASA as we speak. not sure of the thermodynamic pitfalls you speak of, but they wouldnt be because of the fact that light cant be used to propel the reflective surface. The Russians are currently building Cosmos 1, which they are saying has the potential to reach speeds up to 100km per second. One unknown factor though is that they don't know how ultra thin materials will behave across such large cross sectional areas in zero gravity, and they have no way of testing this on earth, so whether the mission is a success or the aluminum-type material crumples like glad wrap remains to be seen.

 

[dr nick]

Originally posted by CharlieG
Is it true about that philosophy exam at one of the unis where the question was "Why?" and the answer that got perfect marks was "Why not?"

lol. reminds me of the time 4 students slept in for a uni exam, so they all collaborated on an excuse. They all said to the lecturer they blew a car tyre on the way in. "That's ok, you'll just have to sit an alternate test tomorrow"

phew, they thought they were off the hook.

The next day, the exam consisted of just one question.

"Which tyre?"

 

[Stevo]

LOL. Classic.

 

[MightyFighting]

That... never happened, did it Nicko?

 

[daddy_4_eyes]

Originally posted by MightyFighting
That... never happened, did it Nicko?

Its a joke he ripped off the jokes thread

 

[dr nick]

Originally posted by daddy_4_eyes
Its a joke he ripped off the jokes thread

to be honest i didnt see it on the jokes thread. i heard it from someone a few years ago and i wouldnt know if it happened or not.

 

[mellowyellow]

Originally posted by MightyFighting
That... never happened, did it Nicko?

Given the speculative nature of this thread maybe the theory of parallel universe's could accommadate this scenario

 

[Destructive]

Originally posted by CharlieG
It's time for me to confess. I was born in the year 2357. I came back here because I wanted to enjoy the Swans' 2004-5-6 premierships... but time travel is still sort of inexact, and I ended up in 2002. So, I'm sitting it out.

By the way, the Federal Republic of Oklahoma is the next target in the war on terror, if you're interested.

Charlie, you have been around since at least 2001 that I know of....

 

[CharlieG]

Originally posted by Destructive
Charlie, you have been around since at least 2001 that I know of....

Smarty-pants!