More debate, semantics and two Harry Potter references in One Day

Posted: January 5, 2012 in Physics

I recently read a good article on USAToday and posted my usual comments.

http://www.usatoday.com/tech/science/columnists/vergano/story/2012-01-02/international-linear-collider/52324768/1?fb_comment_id=fbc_10150440541135684_20252738_10150440549700684&ref=notif¬if_t=open_graph_comment#f1bc5d7b18

What hit me was that semantically people may disregard what I am saying due to the fact hard core folks now assume invariant mass to be the norm. So from now on when you see or hear me state Relativistic Mass it only relates to solving for c in e=mc2. So no matter how you solve for it I am stating that you are solving for an acceleration not a velocity. And this really makes sense when two people who I debated used their math for my two Parallel Particle Accelerators example and came up with the objects acceleration not its relative velocity.

To state this more simply, If you were to build two large Particle Accelerators(PA1 and PA2) in parallel. PA1 accelerates a particle A to a constant velocity of 99%c in one direction while PA2 accelerates a particle B to a constant velocity of 99%c in the opposite direction. If they passed each other midway after one time unit how far apart would A be from B? After 2 time units how far apart would they be? My math says that for each time unit after they pass the distance between them is 2*99% the distance light travels in one time unit. So B is traveling nearly 2 times the distance light can travel in one time unit away from A. So we either figure out away that LTs deal just with acceleration or we throw them out completely since using them plus relativistic mass to state nothing can have a velocity greater than the speed of light is wrong. So my first goal is to get rid of the speed limit. After that I do not much care if someone thinks anything in four-dimensional space can be at rest. But using LT’s to express a relative acceleration makes sense since one object would be accelerating not just moving a constant velocity.

Peter Lane · Northern Illinois University

Rick, you stated that the particles are accelerated to a *constant velocity*, so when the particles pass each other the calculations are no more complicated than standard relativistic velocity calculations. In this case, Einstein’s velocity addition formula gives 0.99995c. Still less than the speed of light.Also, you absolutely can have an inertial reference frame in Minkowski space where a particle has no velocity. It’s called the “rest frame” and is used all the time in particle collision calculations. I’m not sure what your objection to it is. It’s simply the frame of reference “riding along with” a particle traveling at constant velocity.Lastly, relativistic mass is crap. No serious Physicist uses that concept. Mass is an invariant property of matter. Period. What is modified is the energy. The relativistic energy is gamma * m_0 * c^2, where m_0 * c^2 is the rest energy (energy in the rest frame) of the particle and m_0 is the invariant mass of the particle.

Regardless, it is a fundamental assumption of special relativity that light travels at the exact same speed in all inertial reference frames (this is what leads to Lorentz contraction and time dilation). The reason why we believe this assumption is because there has never been an experiment done that contradicts the results of special relativity. It’s as simple as that. Either come up with an experiment (not fuzzy math that ignores repeated suggestions that you’re failing to use Lorentz transformations) that contradicts special relativity or you simply will never be taken seriously.

To which I replied.
Rick Gillespie

Hi Peter, Thanks for your reply. But I am not disputing the speed of light. Nothing you have stated disproves what I have stated. I am only saying relativistic mass should only deal with acceleration. Particle A and Particle B are moving away from each other at 2*99%c. They are moving away from the middle point at 99%c. If no one uses Relativistic Mass then there is no reason to believe that there should be a speed limit of c on mass in our Universe. And unless you believe Harry Potter is a reality based series why would you accept that any frame in 4 dimensional space can be truly at rest. To me this is the point that physics wrongly turns away from Isaac Newton’s work. And so we have the numerous unanswered questions and anomalies that have been observed since. So we agree to disagree.
Best wishes
And to make yesterday even more interesting the AP posted a story on yahoo http://news.yahoo.com/now-see-now-dont-time-cloak-created-184955175.html
Stating that Physicists have stopped time. And they even referenced Harry Potter. The funny thing is I posted my comment about Harry one hour before I read the story. But it is nice to see that in order for one LT to occur over one whole second with the rest frame truly being at rest it would take a device, and I quote, “18,600” miles long.
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Comments
  1. dbox says:

    Non-physicist and absolute layman, so be considerate in your response. I don’t see how this changes the “speed limit”. If the maximum speed a human can run is 36 mph., and to humans run past each other at this speed, we don’t infer that humans can run 72 mph.

    • jetsrock says:

      Hi dbox,

      Thanks for taking time to comment. Do a quick wiki on velocity versus acceleration I think that will help you understand. Another way to look at it would be to say since a corvette can not go 0 to 100 in one second that it can not go faster than 100.

      Best Wishes,
      Rick

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