Question about Lorentz contraction

[Ziggurat]

Maybe it's because you keep saying the same dumb thing: things that are moving fast will have less energy.

I have NEVER said that. I EXPLICITLY denied saying that several times now, and have on MULTIPLE occasions given the actual EXPRESSION for how much more energy a moving object has. Misinterpreting me once is fine, but this is just getting ridiculous.

Let me make it as unambiguous as I can. Consider two systems:

1) two hydrogen atoms separated by >10 meters, going at a speed of 0.9c
2) two hydrogen atoms bound together into a hydrogen molecule, going at a speed of 0.9c

Which system has more energy? My answer is system 1. This claim has NOTHING to do with the claim that things moving faster have less energy. Do you disagree that system 1 has more energy? Or do you think that system 2 has more energy?

 

[boooeee]

On the ruler problem: I think it becomes a little easier to figure out if instead of a hole, you have a trap door. If the ruler's Lorentz contracted length is 1/4 foot and the trap door's length is 1/2 foot, the person in the rest frame just needs to pull the trap door down when the 1/4 foot ruler is completely over the 1/2 foot trap door.

In the rest frame, the ruler will drop through the hole.

Since dropping through the hole is frame independent, how does this look from the ruler's point of view? It all goes back to relativity of simultaneity.

Even if in the rest frame, the trap door is pulled straight down, from the ruler's point of view, the far edge of the trap door comes down first. Since the trap door is tilted, the ruler can get through a trap door whose length appears to the ruler to be much smaller than the ruler's length of 1 foot.

This is basically the barn pole paradox, with some messy complications thrown in (complications that have little to do with relativity).

 

[boooeee]

Look, Zig, I basically said, "it's got more energy in the bonds when it's moving at relativistic velocities,"

But what Ziggurat's calculations show is that there is NOT more energy in the bonds.

You are correct that the orbitals get squished along the direction of motion. If that was all you considered, you may conclude that that changes the energy stored in the bonds (by virtue of being closer together). In fact, that's exactly what I concluded before being shown my error.

My error was in not considering the fact that not only do the distances transform under a Lorentz transformation, but so do the fields. And the fields transform by the exact amounts such that the energy stored in the bonds is exactly the same.

Granted, this is a classical calculation, but I see no reason why this wouldn't hold for quantum mechanics too.

 

[Macoy]

Here's what my maths teacher sent to me:

 

[Ziggurat]

Here's what my maths teacher sent to me:

That's pretty cool, but it's a Lorenz strange attractor. Note the absence of a t: it's a different guy from the Lorentz who came up with the length contraction formula used by special relativity.

 

[Paulhoff]

OK here we go with a Einstein thought experiment.

We have a spaceship that is not moving, deep in space with no galaxy within 100 million light years. We have slowed down light to 100 feet per second. The ship has no windows or anyway of looking outside. The ship also has a room that is spherical and is 200 feet in size. On the inside of the room in the center there is a man on a chair wearing a helmet with a light on the top. Our spaceman sits in the chair and the light starts to flash once every 4 seconds (This would drive me nuts). He sees that the wall lights up at the same time in all directions after 2 seconds. Now the ship starts to move, (don’t worry, there is no G force for our spaceman, and he does not know that he is now moving) the walls still light at the same time in all directions. Faster and faster, still no change. At 86.6 percent of the speed of light (86.6 fps) and the wall still lights up at the same time in all directions. How can this be, the wall in the direction of movement should not light at the same time as the wall at right angles to the movement. Well this is where the room is no longer a true sphere is has shrink in the direction of movement by 50 percent. Also time has slowed down by 50 percent.

Prove it Paul.

The easy one first, the light hitting the side-wall that is at right angels to the forward movement of the spaceman. The light going to the side-wall will travel at 30 degrees from the spaceman and not 90 degrees. The light will hit the wall after our spaceman travels 173.2 ft but it will be 200 ft of travel for light. The light hits the wall at 30 degrees and bounce back to the spaceman at 30 degrees. It will hit the spaceman after he travels a total of 346.4 ft and it will be another 200 ft for light and a total of 400 ft and a total of 4 seconds.

Well now the fun part, ha, ha. Now the length of the room in the direction of movement is now 50 ft and not 100 ft. The ship is traveling at 86.6 fps it will take about 3.732 seconds for light to hit the front wall after 373.2 ft of travel. At this time our spaceman will have traveled 353.2 ft or 50 ft back from were the light hits the front wall. The light from the front wall travels 26.8 ft back to the 346.4 ft point and at 86.6 fps the spacemen will travel 23.2 ft and meet. Now all the light from all the walls will meet at 346.4 ft or 4 seconds. Light has traveled 373.2 ft forward and 26.8 ft back, total 400 ft. Time is slower by one-half the spaceman thinks only 2 seconds have gone by.

Paul

 

[Macoy]

That's pretty cool, but it's a Lorenz strange attractor. Note the absence of a t: it's a different guy from the Lorentz who came up with the length contraction formula used by special relativity.

Oops. Shows wot i know.

 

[Schneibster]

I have NEVER said that. I EXPLICITLY denied saying that several times now, and have on MULTIPLE occasions given the actual EXPRESSION for how much more energy a moving object has. Misinterpreting me once is fine, but this is just getting ridiculous.

Lesson one: don't argue for the sake of arguing, it makes you look stupid. Keep it up, I'll put you back on ignore; this is why I did in the first place. You're just proving I'm an idiot for taking you off.

 

[Schneibster]

But what Ziggurat's calculations show is that there is NOT more energy in the bonds.

I know what they show; it's a trivial exercise to show they're wrong, one which I'm not motivated to bother with for someone whose entire intent in the first place was harassment. What's your intent here? Why are you doing this? Why is it you keep showing up on threads where crap like this is going on and saying things like this? Got an agenda there, sport?

 

[69dodge]

On the ruler problem: I think it becomes a little easier to figure out if instead of a hole, you have a trap door. If the ruler's Lorentz contracted length is 1/4 foot and the trap door's length is 1/2 foot, the person in the rest frame just needs to pull the trap door down when the 1/4 foot ruler is completely over the 1/2 foot trap door.

In the rest frame, the ruler will drop through the hole.

Since dropping through the hole is frame independent, how does this look from the ruler's point of view? It all goes back to relativity of simultaneity.

Even if in the rest frame, the trap door is pulled straight down, from the ruler's point of view, the far edge of the trap door comes down first. Since the trap door is tilted, the ruler can get through a trap door whose length appears to the ruler to be much smaller than the ruler's length of 1 foot.

This is basically the barn pole paradox, with some messy complications thrown in (complications that have little to do with relativity).

I don't see how a trap door helps. If the ruler, in one frame of reference, apparently can't get through a completely empy hole, how does it help to add a trap door that might or might not block it? Even if it can be shown not to block it, we're no better off than if it weren't there at all.

I still say the important point is that the ruler bends. Agree? Disagree?

 

[Ziggurat]

I know what they show; it's a trivial exercise to show they're wrong,

And yet, you won't do that. Why not? I seem to have convinced everyone else on this thread. If you won't prove me wrong for my sake, why not prove me wrong to them? Isn't that sort of the whole point of posting here, to spread knowlege? Why should your annoyance at me keep you from correcting the record for them? Unless, of course, you aren't able to...

one which I'm not motivated to bother with for someone whose entire intent in the first place was harassment. What's your intent here? Why are you doing this? Why is it you keep showing up on threads where crap like this is going on and saying things like this? Got an agenda there, sport?

My entire intent was to answer the original question. And I did, and everyone except you seems satisfied with the answers I provided. You know, this isn't all about you. I don't point out that what you said was wrong in order to harass you, I point out what you said was wrong because I believe it WAS wrong, and you've done nothing to convince me you're right on the fact. You're the one who's no longer willing to argue the physics, not me. You're the one who made it personal (again), not me. You're the one who interprets a disagreement about technical issues as a personal affront, not me. So quit playing the victim and answer the actual physics questions I posed to you. Surely if it's so trivial that wouldn't actually be hard, would it?

 

[boooeee]

I know what they show; it's a trivial exercise to show they're wrong, one which I'm not motivated to bother with for someone whose entire intent in the first place was harassment. What's your intent here? Why are you doing this? Why is it you keep showing up on threads where crap like this is going on and saying things like this? Got an agenda there, sport?

No agenda. I just find these types of questions interesting. I'm not trying to harass you. I would just like to understand your position.

I'm not trying to play a "gotcha" game here. You say it's a trivial exercise to show that the calculations are wrong. I'm honestly interested in the details of the exercise. If you don't want to spell it out, I guess my participation in this part of the thread is done.

 

[boooeee]

I don't see how a trap door helps. If the ruler, in one frame of reference, apparently can't get through a completely empy hole, how does it help to add a trap door that might or might not block it? Even if it can be shown not to block it, we're no better off than if it weren't there at all.

I still say the important point is that the ruler bends. Agree? Disagree?

I think I agree. I thought the introduction of the trap door would eliminate the need for bending. That doesn't appear to be the case. The ruler has to bend.