Cap'n Refsmmat

And details aren't publicly available, so you should be fairly safe.

No. If he's standing in the train and lobs the ball at 10m/s in the direction of the train's travel, then measures the ball's speed with a radar gun, he'll get an answer of 10m/s. A guy standing on the platform will get an answer of 30m/s, because the train was initially moving at 20m/s. Both of them are correct. It is apparent to me that you have not expended any effort at all in trying to teach yourself more about relativity. You do not seem to be interested in learning.

...How does that change what I said? You can still measure different velocities of it from different reference frames.

How does that change what I said?

All that is true. I did point out that from different frames of reference you get different velocities. From the point of view of someone sitting in the station the velocity of the train is 20m/s. Someone hurtling through space sees it as 7600m/s. They're both right. That's relativity.

I wasn't talking about the train. I was talking about the rocket ship. You have plenty of reference points to compare the train's velocity against.

It's not an illusion. You're right and he's right. Reality can be different from two different perspectives, and neither perspective is any more correct than the other. Please go read up on special relativity. If you insist on being argumentative and remaining ignorant about relativity (while trying to prove it wrong), I'm going to start closing these threads.

2m. But you measure him as a little bit shorter. You're both right.

Another option is Textpattern. It's simple, but someone with PHP skills can add on to it very easily and make it do almost anything. I set it up to do http://www.dbunked.com with a custom plugin or two and very little work. If it helps, I think The Onion uses Drupal for their website. You can look there to see what's possible with Drupal.

Supposing I account for the two seconds it takes for light to reach me from the moon? (Not that it would have any effect at all anyway, as it'll affect all my numbers equally and my answer will end up being the same anyway.) Why do you have to argue with physics that has been accepted and experimentally proven over nearly 100 years when you could just try to understand it? Length contraction. I posted a link to an explanation of the phenomena before.

We are measuring the astronaut's velocity.

He will report that he traveled a certain number of miles in a certain period of time. He is correct. However, your measurements from Earth will reveal that he traveled more miles -- because he was on the Moon, which is moving in an orbit around the Earth. So you will say his speed is greater because he is standing on a moving object. You both have perfectly valid numbers for speed -- his is not the "actual" number.

You made an error in your observations. If you try it the way I described, you'll get the same effect with correct observations.

You aren't going to find an official Firefox 3 package for Fedora Core 4. Linux distributors will often freeze versions in their repositories to keep everything nicely compatible, and Fedora Core 4 has probably already had that happen. You'll only be able to get bugfix updates for Firefox, not feature updates. You can try downloading Firefox from mozilla.com and untarring it into a new directory. (It needs to use a new profile as using an old one may screw it up royally.)

No. You're measuring his velocity wrong. The moon isn't 1 foot in diameter. Let's say you went to an astronomical observatory and measured the angle between his position in the telescope at the start of the journey and at the end of the journey, then used trigonometry to produce a number for his speed. It would vary greatly from the number his speedometer stated -- because not only is he moving across the moon, but the moon is moving across the sky. In that case, you are both correct about his velocity. That is indeed a key point.

Right. And that's the way classical physics works. But you have to agree that an astronaut armed with a radar gun would give the numbers I stated above, because he's measuring the velocity of the train compared to his space shuttle. But when you venture into relativity, you can't just say "it's going 20m/s." In relativity, all reference frames are equal, meaning the astronaut is just as justified in measuring the speed of the train as 7600m/s as you are measuring it as 20. You're both correct in your measurements.

I think the point of the game is that you have no idea what your initial velocity is, nor do you have any way of telling.

What version of Fedora are you running? "yum update firefox" is most likely the way to go, but Firefox 3 packages might not yet be available in the repositories for the version of Fedora you're using.

If I'm standing on top of the train and point my radar gun at the train, I'll measure it to be moving at 0 m/s. A guy standing at the platform will measure it to be moving at 20m/s. A guy in orbit around the Earth on the space shuttle will measure it to be going 7600m/s. A guy floating around in space might measure it to be going 593,294m/s. They're all right about its speed compared to them. (Add 10m/s to all those numbers to get what they'd measure the speed of the thrown ball to be.) The point is that you can't define an "absolute" speed because you have to define what you're going to measure its speed against.

http://www.scienceforums.net/forum/showpost.php?p=417183&postcount=31 You could try to maintain the acceleration rate for more than a few milliseconds, but you'd find yourself only asymptotically reaching c. Your acceleration would slow down and you'd be going insanely fast, but the energy required to reach c is essentially infinite. You could never maintain that acceleration for more than a few milliseconds (and a few milliseconds is all we need to reach our desired speed).

Then the ball is thrown at 10m/s. Yes. The point is that this works at slow speeds. But the same "the train's going 20m/s, and I threw the ball at 10m/s, so it's going 30m/s" addition does not work at high speeds. Special relativity steps in and makes things complicated.

He's standing on a train moving 20m/s and lobs the ball at 10m/s in the direction of travel of the train. A guy standing inside the train with a radar gun will record the ball traveling at 10m/s. A guy standing on the platform will record the ball traveling at 30m/s.

These aren't against the laws of physics. It's just a really awesome spaceship. It's not breaking any physical rules like your car traveling the speed of light.

The amusing part is that nothing happens when I click on it.

Yeah, I'd try that. Flash crapped out on me and it took two installation attempts to get it working.