# Yet another Relativity Buster Question

Discussion in 'Physics & Math' started by Singularity, Feb 20, 2006.

1. ### SingularityBannedBanned

Messages:
1,287
Hi,

a man fires a Laser from point A1, the laser takes 10 minutes to reach and destroy an ball at point B1. A Rocket R1 passes by A1 at the same instance when the laser is fired. The rocket is 99% speed of light relative to A1 and B1.

After how long should laser destroy the ball for R ?

3. ### PeteIt's not rocket surgeryModerator

Messages:
10,166
ten minutes times &radic;(1 - 0.99&sup2

= 600 sec x 0.14 = 85 seconds

85 seconds pass on clocks on the rocket in between the laser being fired and the ball being destroyed.

Messages:
1,612
.r?

7. ### CANGASRegistered Senior Member

Messages:
1,612
Pete:

You jumped the clock again in your setup.

R?

Do you ALWAYS answer questions amazingly quickly even though they are indefinitely undefined?

R U clairvoyant?

8. ### 2inquisitiveThe Devil is in the detailsRegistered Senior Member

Messages:
3,181
I don't see a problem with the way Singularity posed the question. R1 is the rocket travelling at .99c in A1's frame of reference (think primed). R is the rocket's rest frame, the rocket's clock. Do you always have such a problem understanding questions, CANGAS? Haha, just returning the favor. I don't get mad, but sometimes I feel the need to get even.

9. ### geistkieselValued Senior Member

Messages:
2,471
Singularity,
The laser travels the distance D = 10 c. The same distance traveled by the rocket is 10c = (.99c)t, or t = 10c/.99c = 10.101 minutes.

The rocket arrives .101 minutes or 6.06 seconds after the ball has been destroyed by the laser.

Geistkiesel​

10. ### SingularityBannedBanned

Messages:
1,287
So for the rocket, the laser travels form A1 to B1 in , Ummmm.

Can U all answer that again with a consensus please. Asuming that the rocket is going from A1 to B1.

11. ### SingularityBannedBanned

Messages:
1,287
Howz that ? The distance is already been told, ie. 10 light minutes

12. ### SingularityBannedBanned

Messages:
1,287
Pete's 85 = 6.06 ?

13. ### 2inquisitiveThe Devil is in the detailsRegistered Senior Member

Messages:
3,181
Singularity, the title of your thread indicated you wanted an answer according to the Special Theory of Relativity. Pete provided the answer according to the rocket's clock (R) in its frame of reference. According to Special Theory, time beats slower and distance is contracted in the rocket's (R) frame of reference according to the man at A1. It takes 10 minutes of A1's time on his clock for the laser to reach the ball at B1. A1 'sees' R's clock beating much slower and less than 85 seconds pass on that clock. The unnamed observer on the rocket would see the distance between A1 and B1 contracted and he would reach the location of the ball in 85 seconds of his clock because of the contracted distance. He still would not reach the ball before the laser beam because of the contracted distance between A1 and B1 in his frame of reference. The laser beam would also have the shorter distance to travel and hit the ball before he (R) arrived. That is relativity theory as best I can describe it in simple language.

Geistkiesel doesn't believe Special Theory is correct and he gave the time required by Newtonian Mechanics. Time and distance are absolute in Newtonian Mechanics, both are varibles in Relativity Theory. It takes quite a while to gain a working knowledge of Special Relativity and many years to do the same in the much more complicated General Theory of Relativity. I don't have such knowledge, only a basic philosophical understanding.

14. ### SingularityBannedBanned

Messages:
1,287
Thanks.

And what if there were MileStones between A1 and B1 noting miles covered ?

Thanks but the question was not about if she can speed up faster than light.

I think its a she.

Are U suggesting Geistkiesel is imcompetent ?

15. ### geistkieselValued Senior Member

Messages:
2,471
Singularity,
SRT is based on the belief that there is no such thing as relative motion of a frame and a photon. SR then negates the concept of motion. This is based on Einsteins garbled development of SR as described in his 1916 book "Relativity", chapter VII.

There he analyzed the expression c - v = w, where c and v are the speed of light and the carriage both measured wrt the embankment, the vacua. He said, regarding w, 'but this cannot be. The speed of light according to relativity principles means the speed of light must be the same when the carriage is the coordinate frame as when the embankment is the coordinate frame.

There are two things wrong with this analysis.

1. The expression c - v = w were measurements made of c and v with the vacua, embankment as coordinate frame of reference. Einsteins stating that w was measured wrt the carriage as coordinate reference frame is misplaced, negligently or fraudulently. Therefore all analysis assuming that w was measured wrt the carriage as coordinate frame is just plane erroneous.

2. The relativity principle Einstein was refering was: The laws governing the motion of light must be the same when the carriage is the coordinate frame of reference as when the vacua is the coordinate frame of reference. There is nothing wrong with this statement up to here but then Einteins trashes physics as he continues. He mis-stated the principle. It should be stated that the laws governing motion should be the same whether the carriage is the coordinate frame or the embankment is the coordinate frame. Relativity does not distinguish between light and material objects, only Einstein does.

This does not imply that all relative motion should be the same nor does this distinguish between material objects and light motion. Einstein saying that the relative speed of frame and photon is always c is pure bullshit crap and was no more justified in 1906 when he published the SR paper as it is today, or in 1916.

Einstein, the proven plagarist of plagarists is a thief of the highest proportions. He stole the work of Lorentz (bullshit that it was) and Poincaire' as he failed to recopgnize their work in the original published paper where the world assumed it was all Einstein's effort. The eclipse experiment, that made Einstein famous over night of 1919, was a testament to the lawless scientists, primarily Eddington, foisting manufactured and mistated experimental results on an unsuspecting and gullible media and public. Einstein admitted that the photographs of the stars required measurements of hundreths of a millimeter, when the resolution of the telescopes was many times greater than the "hundrethds of a milimeter". Einstein must have known what he was lying about, as did Eddington and all others involved in the charade of 1919.

Einstein was and is a dishoinest man that has crammed the bullshit of SRT into the minds of those unable, and/or unwiulling to have made any critical analysis of that which they learned in school, taught by those who also bought into publicly popular, though less than useless mathematical nonsense.

Geistkiesel ​

16. ### SingularityBannedBanned

Messages:
1,287
Wow, I am sorry if I offended U Geistkiesel.

But we do get lens effects, so what about that ?

17. ### ZephyrHumans are ONERegistered Senior Member

Messages:
3,371
If you don't like Einstein, try this - different derivation; same result.

For those who distrust special relativity, one question I have is - how is it that synchrotrons which make corrections according to relativistic mass manage to work?

If you want to find inconsistencies in relativity, why not try meshing general relativity with quantum mechanics? You might get a nobel prize. Trying to find internal inconsistencies seems unlikely to work.

18. ### MacMRegistered Senior Member

Messages:
10,104
Does your calculation include the propagation delay about the destruction back to the rocket or did you just quote a universal time for its destruction?

19. ### SingularityBannedBanned

Messages:
1,287
I was asking without the reflection.

I am asking what will be the light distance for the same in Rockets frame.

For A1 and B1 its 10 minutes.

20. ### Janus58Valued Senior Member

Messages:
1,788
Because for the Rocket, the distance between A1 and B1 is not 10 lm ( about 180,000,000 km) but 85 ls (about 25,500,000 km)

21. ### Janus58Valued Senior Member

Messages:
1,788
Let's go a step better. Let's say that there is a tape measure stretched between A1 and B1, marked in meters. The rocket also carries a meter stick, which it holds right next to the tape measure as it travels along side it. When the the Rocket compares it meter stick to the tape, it will note that a tad more than 7 marks on the tape will fit between the ends of his meter stick.

He will also note that there are 180,000,000,000 of these marks between A1 and B1. At 7 marks to a meter, this gives a distance of 25,500,000,000 meters between A1 and B1 according to the rocket.

22. ### PeteIt's not rocket surgeryModerator

Messages:
10,166
Hi Singularity,
Let's leave Einstein alone for a minute, and go back to when people first figured out that perhaps the Earth isn't a a rock solid firmament, fixed in space.

Before then, when people talked about distances, there was no ambiguity. If it was measured that Tatyana Kotova jumped 7m in a long jump, then there was no question that the distance from were she took off to where she landed was 7m, right?

But then, we found that the Earth isn't fixed in space after all, and things changed...
If the Earth's surface is turning at 300 m/s (depending on your latitude), then isn't the real distance between Tatyana's take off and landing a lot more? If she's in the air for 1.5 seconds, and the Earth's surface moves 450m in that time...

But we also shouldn't forget that the Earth is whizzing round the Sun at 48 km/s, the Sun is flying around the Milky Way at 220 km/s, and the galaxy is moving relative to other galaxies!

So what is the real distance of Tatyana's jump?
The best answer is that there's no "real" distance, that we can only measure distance travelled relative to something:
• Relative to the ground, there is 7m between Tatyana's takeoff and landing.
• Relative to the Earth's axis, there is maybe 450m between Tatyana's takeoff and landing.
• Relative to the Sun, there is maybe 70km between Tatyana's takeoff and landing.
• Relative to the Milky Way, there is maybe 300km between Tatyana's takeoff and landing.

That is what relativity is all about... that some measurements only mean something relative to something else.

It isn't hard to see that position is relative (can you describe where you are without referring to some other location?), and it's not much harder to see that speed and velocity is relative (how fast is Tatyana going during her run-up?).

These things aren't immediately intuitive - it took 2000 years from Aristotle to Galileo and Newton to fully realise that position and speed are relative measurements - but it's been well understood since the work of Newton in the 17th century.

Then came Einstein... but we'll get to Einstein's relativity shortly.

First, let's think about our rocket and the laser using Galileo's relativity.

Relative to the rocket, what is the distance from A1 to B1?

Last edited: Feb 21, 2006
23. ### CANGASRegistered Senior Member

Messages:
1,612
2inq.:

Not only do you not get mad, you do not even get even. You need to get your seeing eye dog a seeing eye dog, then make a real team effort to read posts prior to answereing them.

As for you not understanding about my understanding, it is painfully obvious that there are many things that you do not understand. Quit bragging about it.