Recent content by Tommy White

It's a little bit weird imo saying "the speed of light" (without c) and "the Planck constant" (without h) and then just G, so a little advice it's better to be complete and clear, specially if you're going to write an article once upon a time .. so Gravitational constant, G. Yes, measurements...

A "yes" for a change ;). All (fundamental) physical constants are 'invariant' as in observer independent. But the Planck’s constant or Boltzmann’s constant are not called 'Lorentz invariants'. (In GR, of course G=c=1 so it would be really weird if it wasn't.)

I remember this. @HansH only actually, coz I know him a bit for a while. I see that you have also grabbed the two peaks of PP again, sigh 😉. But that's also just a diagram, not a representation of an actual geodesic. Those peaks have no physical meaning whatsoever, as explained by Prof...

I meant this as a reaction to the article, I didn't knew there was a whole conversation about it where this comes from out of nowhere I image. (Thought I might had to clarify that just in case.)

Thanks. I saw the table of contents of it and for me to understand that I imagine would be quite a struggle mathematically. Not that I'm not capable of understanding the math, but I find it hard (unfortunately) to enjoy studying mathematics without it having any physical meaning. But I...

Ok, thanks very much! Got to take it all in slowly though. I thought inertial mass and gravitational mass were the same, because although inertial mass, passive gravitational mass and active gravitational mass are conceptually distinct, no experiment has ever unambiguously demonstrated any...

Makes me think of what Feynman sais here: (Of course there are theoretical physicists and mathematical physicists though. A lot of physics can be explained by using just words, but none to apply it.)

Well, yes. But inertial mass, gravitational mass, rest mass, effective mass etc. is all the same: just mass, right? (And historically there was also transversal mass and longitudinal mass, electromagnetic mass, relativistic mass which is still used sometimes though. Those are things of the past...

Ok, thank you.

Well I could write a lot about it. But I think understanding Einstein's paper "Does the inertia of a body depend on its energy content?" explains it quite well. Which in a nutshell tells that the inertial mass of a body increases (or decreases) by the amount m=E/c^2 if its energy content...

Yes, that's true. I'll have to look it up later though. What about Wikipedia by the way?

Yes, I understand that. As well as the mass-energy equivalence.

I'm not even sure whether it can be defined in QFT, but I got this from SE: Which I don't understand. I'm not mathematically sophisticated enough for that.

Hi, I'm Dutch, not any kind of Quark ;-) (so excuse me for any bad English) and I'm very curious about "how the universe works". Cosmology/astrophysics and modern physics (quantum, relativity). I find it all mighty intersting. Actually all physics and also how it's all developed and "evolved"...